VGTU Journals (Vilnius Gediminas Technical University - Vilnius Tech)
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Still dirty: the effect of global risks and development on foreign direct investment inflow
No full textThere needs to be more research on the global risks and developmental determinants of foreign direct investment inflow with green investment campaigns. This article presents new evidence covering 116 countries (2018–2020) using least squares regression. We show that ceteris paribus, higher perceived environmental and geopolitical risks are more likely to increase foreign direct investment. We also find that lower business environment, safety and security, and environmental sustainability increase foreign direct investment inflow. Meanwhile, foreign investment inflow increased positively according to price competitiveness, infrastructure quality, and natural resources. One development variable, information, and communication technology readiness, becomes significant when the analysis is performed only on developing countries. Economic risks, societal risks, technological risks, health and hygiene, human resources, and international openness are not significantly affecting investment inflow. An insightful theoretical implication regarding the finding is that some supports exist for the pollution haven hypothesis. Implications for practice include creating supportive policies that appreciate sustainable practices, such that investors are attracted to the country not as opportunistic polluters but as sustainability pioneers
Family business resilience in crisis: study case analysis in a collectivist society
No full textIn an era marked by persistent challenges and uncertainties, gaining insights into how family businesses navigate crises becomes imperative. While previous research has delved into the resilience of family firms, there is a notable absence of a comprehensive exploration into how inherent traits in family businesses, particularly within collectivist societies, contribute to their resilience during crises. This study aims to fill this gap and elucidate the distinctive dynamics and behaviours exhibited by family businesses in such cultural contexts. Utilising qualitative case studies and interviews, this research delves into nuanced insights into the dynamic approaches employed by these businesses. The family firms demonstrated adaptability by adjusting their operations and leveraged human resources by seeking support from family members. Additionally, they showcased creativity in enhancing market offerings. The study also reveals unique behaviours, particularly resilience through collaboration with competitors. This research makes an academic contribution by offering insights into the behaviour of family businesses within collectivist cultural contexts during crises. From a practical standpoint, it informs the development of tailored crisis management strategies for family business owners and policymakers, underscoring the significance of collaboration among competitors. The study emphasizes avenues for fostering innovative approaches, promoting resilience, and ensuring sustainability within the ever-evolving business landscape. Furthermore, it establishes a foundation for future explorations, urging further investigation into crisis adaptation strategies tailored to the cultural contexts in which family businesses are situated
Mapping of organizational democracy: a bibliometric study
No full textSocial, economic and political developments in the globalising world have necessitated a re-examination of the concept of democracy. The concept of organisational democracy is a process that expresses the inclusion of individuals in the management processes of organisations and allows freedom of expression in organisations. In this study, it is aimed to reveal at which stage the concept of organisational democracy is included in the international literature. In this context, it is desired to evaluate the development stages of the concept in terms of literature and to set an example for future studies by filling the gaps in the literature. In line with the main purpose, 99 publications related to the concept of “organisational democracy” between 1990 and 2023 in the Scopus database were analysed using R Studio and VOSviewer softwares. The analyses were evaluated by considering the studies conducted in the fields of “Social Sciences”, “Business, Management and Accounting” between 1990 and 2023. The concept of organisational democracy is often associated with concepts such as participation, hierarchy, employee participation organizational culture, organizational commitment and communication. As a result, it has been determined that organisational democracy plays a role in the satisfaction of internal stakeholders
Educational data mining and learning analytics: text generators usage effect on students’ grades
No full textToday, various types of data are constantly growing, so they can be used for different purposes. In this investigation, educational data has been analyzed to determine the influence of assessment on student knowledge. The newly collected dataset has been prepared and statistically analyzed. The dataset consists of open-question answers collected on one study subject during the midterm exam at Vilnius Gediminas Technical University. The results of the statistical analysis have shown that by using the text generators, students obtained higher grades by paraphrasing the answers to the questions in good quality. Furthermore, research has shown which types of questions are more difficult for students to answer without additional material and using text generation tools. It can be useful for lecturers planning course assessment tasks
Just-In-Time Software Defect Prediction using a deep learning-based model
No full textThe increase in software complexity, driven by technological developments and user demands, has created major challenges for companies in Software Quality Assurance. Companies seek efficient ways to identify and mitigate defects, recognizing that they cause high financial costs and other problems with negative impacts on business. Among defect prediction approaches, Just-In-Time Software Defect Prediction has received increased attention from software industry professionals in recent years. This technique aims to identify and treat defects early, to improve the quality of the software development cycle. This study proposes a Deep Learning-based approach for Just-In-Time Software Defect Prediction using a large dataset of historical data from several popular software projects. The Deep Learning model was trained to identify defects by analyzing the software metrics provided by the dataset. The model achieved an accuracy of 82.08% in its predictions, and it was possible to determine the most relevant metrics for its conclusions through interpretability techniques. The results obtained demonstrate the potential of Just-In-Time Software Defect Prediction as a tool for improving software quality and encouraging the development of new studies and improvements in this area of research.
First published online 17 January 202
Companies‘ structural changes and wages
No full textThe article analyzes how structural changes taking place in companies affect wages and determine their changes. It is relevant to examine how the structural changes of companies are related to wage indicators, because this reveals one of the most important economic consequences of the structural changes of companies, which is also significant at the level of the national economy. The aim of the research is to theoretically base the essence of structural changes, to empirically evaluate how the structural changes of companies and wages are related. A statistical study was conducted, investigating the links between wages and structural changes in Lithuanian companies. The method of correlation-regression analysis was applied. The results of the study show that one of the most prominent structural effects affecting wages is the development of enterprise activity (judging by indicators of turnover and investment in fixed assets) – this structural change is positively correlated with wage growth. Another structural change in companies, which is associated with the increase in wages, is the growth of foreign capital in domestic companies. The results of the study have practical significance in understanding the factors that determine wage growth in the country’s companies and forecasting wage growth.
Article in Lithuanian.
Įmonių struktūriniai pokyčiai ir darbo užmokestis
Santrauka
Straipsnyje analizuojama, kaip įmonėse vykstantys struktūriniai pokyčiai veikia darbo užmokestį ir lemia jo pokyčius. Aktualu nagrinėti, kaip įmonių struktūriniai pokyčiai susiję su darbo užmokesčio rodikliais, nes tai atskleidžia vieną svarbiausių įmonių struktūrinių pokyčių ekonominių pasekmių, reikšmingų ir šalies ekonomikos lygmeniu. Straipsnio tikslas – teoriškai grindžiant struktūrinių pokyčių esmę, empiriškai įvertinti, kaip susiję įmonių struktūriniai pokyčiai ir darbo užmokestis. Atliktas statistinis darbo užmokesčio ir struktūrinių pokyčių Lietuvos įmonėse sąsajų tyrimas. Taikytas koreliacinės regresinės analizės metodas. Tyrimo rezultatai rodo, jog vienas ryškiausių struktūrinių poveikių, veikiančių darbo užmokestį, yra įmonių veiklos plėtra (vertinant pagal apyvartos ir investicijų į ilgalaikį turtą rodiklius) – šis struktūrinis pokytis teigiamai koreliuoja su darbo užmokesčio augimu. Kitas įmonių struktūrinis pokytis, siejamas su darbo užmokesčio didėjimu, yra užsienio kapitalo šalies įmonėse augimas. Tyrimo rezultatai turi praktinę reikšmę suvokiant veiksnius, lemiančius darbo užmokesčio augimą šalies įmonėse, ir prognozuojant darbo užmokesčio augimą.
Reikšminiai žodžiai: įmonė, verslas, struktūriniai pokyčiai, darbo užmokestis, kapitalas, užsienio kapitalas, darbuotojų skaičius
Possibilities of applying a low-temperature centralized heat supply network in a multi-apartment building district
No full textLithuania‘s district heating (DH) network tends to maintain high heat transfer temperatures, which limit the efficiency of the system. The aim of this study is to assess the impact of DH and reduced heat transfer temperature in the building on space heating and the possibility of reducing the heat transfer temperature (down to 60 °C) in the DH network by looking at different scenarios and the heat demand of buildings. Three alternatives were analysed: the installation of a temperature-lowering module (mixing unit) in the thermal chamber and the retro-fitting of existing piping and heating appliances, where the temperature of the DH fluid is lowered up to 60 °C and the temperature of the radiators is lowered to 60/40/20. The possibility of lowering the DH heat transfer temperature without upgrading the network by installing heat pumps individually in the buildings or in the heat chamber is examined. An hourly data analysis of a 2-year heating system model for a typical building showed that lowering the DHW temperature to 60 °C and leaving the existing area of heating appliances in the building will not meet the heat demand of the buildings.
Article in Lithuanian.
Žemos temperatūros centralizuoto šilumos tiekimo tinklo pritaikymo galimybės daugiabučių namų kvartale
Santrauka
Lietuvos centralizuotuose šilumos tiekimo tinkluose dažniausiai išlaikomos aukštos šilumnešio temperatūros, kurios apriboja sistemos efektyvumo didinimą. Straipsnyje siekiama įvertinti centralizuoto šilumos tiekimo tinklo (CŠT) ir pastate sumažėjusios šilumnešio temperatūros įtaką patalpų šildymui bei šilumnešio temperatūros žeminimo galimybes (iki 60 °C) CŠT tinkle apžvelgiant skirtingus scenarijus bei siekiant užtikrinti pastatų šilumos poreikius. Buvo analizuojamos 2 alternatyvos: temperatūras žeminančio modulio (pamaišymo mazgo) šiluminėje kameroje įrengimas bei esamų vamzdynų ir šildymo prietaisų modernizacija, kai žeminama CŠT šilumnešio temperatūra iki 60 °C, o radiatorių temperatūrinis grafikas – 60/40/20. Išnagrinėta galimybė žeminti CŠT šilumnešio temperatūrą be pastato šildymo sistemos modernizavimo įrengiant šilumos siurblius (ŠS) individualiai pastatuose. Atlikta tipinio pastato 2 metų šildymo sistemos modelio valandinė duomenų analizė parodė, kad žeminant CŠT temperatūrą iki 60 °C bei pastate paliekant esamą šildymo prietaisų plotą pastatų šilumos poreikis bus nepatenkintas.
Reikšminiai žodžiai: centralizuotas šilumos tiekimas, 4 kartos centralizuotas šilumos tiekimas, šildymo sistemos temperatūros žeminimas, šilumos siurblys
Topographical effects on wave scattering by an elastic plate floating on two-layer fluid
No full textThis article illustrates the hydroelastic interactions between surface gravity waves and a floating elastic plate in a two-layer liquid with variable bottom topography under the assumptions of small amplitude waves and potential flow theory. In this study, semi-infinite and finite-length plates are considered. The eigenfunction expansion method is applied in the fluid region with uniform bottom topography. A system of differential equations (mild-slope equations) is solved in the fluid region with variable bottom topography. From the matching and jump conditions, the solution is expressed as a linear algebraic system from which all the unknown constants are computed. We explored the effects of density ratio, depth ratio, and bottom topography on the bending moment, shear force, and the deflection of the elastic plate. Results show that when the density ratio becomes closer to one, the occurred bending moment and shear forces to the elastic plates tend to diminish. The bending moment and shear forces to the pates are higher and lower at a smaller depth ratiofor the incident surface wave and interfacial waves, respectively. The variations in the bending moment, shear force, and plate deflection, caused by surface and interfacial waves, are observed to be in opposite trends, respectively. Bottom profiles similarly affect semi-infinite and finite-length plates when they undergo free-edge conditions. These effects, however, are substantial when the plate is simply supported at the edges. Elastic plate with free edges experiences lower deflection for concave-up and plane-sloping bottoms for incident surface and interfacial waves, respectively
Two-grid virtual element discretization of quasilinear elliptic problem
No full textIn this paper a two grid algorithm for quasilinear elliptic problem based on virtual element method (VEM) discretization is proposed. With this new algorithm the solution of a quasilinear elliptic problem on a fine grid is reduced to the solution of a quasilinear elliptic problem on a much coarser grid, and the solution of a linear system on the fine grid. A priori error estimate in H1 norm is derived. Numerical experiments are carried out to illustrate the theoretical findings
A Singular nonlinear problems with natural growth in the gradient
No full textIn this paper, we consider the equation with boundary conditions where is an open bounded subset of is a Leray-Lions operator defined on is a characteristic function, and is a Carathéodory function such thatsign Forand sufficiently small, we prove the existence of at least one solution u of this problem which is moreover such that the function belongs tofor some This solution satisfies some a priori estimates i