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Implicit extended discontinuous Galerkin scheme for solving singularly perturbed Burgers\u27 equations
Get PDFWe present the implicit-modal discontinuous Galerkin scheme for solving the coupled viscous and singularly perturbed Burgers’ equations. This scheme overcomes overshoot and undershoots phenomena in the singularly perturbed Burgers’ equations. We present the stability analysis and obtain suitable ranges for penalty terms and time steps. Also, we gain the constant of trace inequality for the approximate function and its first derivatives based on Legendre basis functions. The numerical results have good agreement with the analytical and available approximate solutions
Plane waves at an interface of thermoelastic and magneto-thermoelastic media
Get PDFThis research examines the propagation of waves in a semi-infinite, isotropic magneto-thermoelastic solid, and a semi-infinite thermoelastic solid with welded contact. The study investigates the influence of a magnetic field on amplitude coefficients for the incidence of thermal, SV, and P waves in the magnetothermoelastic solid in a semi-infinite space. The incidence of these waves results in a total of six waves, including both refracted and reflected waves. The fluctuation of amplitude coefficients for various magnetic pressure values is explored for copper and aluminum as numerical constants. The study observes that the amplitude coefficients of seismic waves, occurring during the incidence of thermal, SV, and P waves in the magneto-thermoelastic solid semi-infinite space, are dependent on the incident angle, magnetic field, and material constants. Notably, the amplitude coefficients for the incidence of SV waves exhibit only a minor influence from the magnetic field. The implications of this research extend to applications in ocean acoustics, geophysics, acoustic devices, composite materials, and non-destructive testing
Understanding the dynamics of urban heat island as a function of development regulations
Get PDFThis study is the first-ever attempt to relate the tools of development control like Floor Space Index (FSI/FAR), ground area covered by building footprints (BFs), and proportions/configurations of open areas, with their impact on the surface urban heat island (SUHI) which modulates the air temperatures. In the case of the Indian megacity Mumbai, statistical analysis of the land surface temperatures (LST) and its correlation with the selected development indicators, reveals that for an FSI increase of 1.0 to 1.8 the SUHI is found to be–2.5 °C less and when BFs reduced from 90% to 42% SUHI was also reduced by –2.5 °C. Highrise development with a large plot size is desirable whereas low-rise development with FSI 1.0 on small plot sizes exhibits the highest SUHI. Open spaces without vegetation do not reduce SUHI. The correlation of development regulations with SUHI intensity will help urban planners to make more informed decisions
Life cycle assessment of a condensing gas boiler and compare with an air source heat pump in a residential building
Get PDFThis study presents a comprehensive life cycle assessment (LCA) comparing the environmental impact of a Condensing Gas Boiler (CGB) and an Air Source Heat Pump (ASHP) within the context of a residential building. As the demand for sustainable and energy-efficient heating solutions rises, evaluating the environmental performance of these technologies becomes crucial for informed decision-making. The assessment encompasses the entire life cycle of both heating systems, including raw materials, production, transportation, installation, operation, and with deep focus on end-of-life disposal through recycling, landfill, and incineration. The environmental indicators considered in the analysis include greenhouse gas emissions, energy consumption, and other relevant impact categories. This study has been conducted using SimaPro 9.4.0 program database with IMPACT 2002+ method and findings from this research aim to guide homeowners, policymakers, and industry stakeholders in making informed decisions regarding the adoption of heating technologies in residential buildings. By shedding light on the environmental implications of CGBs and ASHPs, this LCA contributes valuable insights toward the transition to sustainable and energy-efficient residential heating solutions and destruction methodologies for better environmental gain.
Article in English.
Gyvenamojo pastato kondensacinio dujų katilo gyvavimo ciklo vertinimas ir palyginimas su oro šilumos siurbliu
Santrauka
Šiame tyrime pateikiamas išsamus gyvavimo ciklo vertinimas, kai lyginamas kondensacinio dujinio katilo (KDK) ir oro šilumos siurblio (OŠS) poveikis aplinkai gyvenamajame pastate. Didėjant tvarių ir efektyviai energiją vartojančių šildymo sprendimų paklausai, šių technologijų aplinkosauginio veiksmingumo vertinimas tampa labai svarbus priimant pagrįstus sprendimus. Vertinamas visas abiejų šildymo sistemų gyvavimo ciklas, įskaitant žaliavas, gamybą, transportavimą, įrengimą, eksploatavimą ir atliekų tvarkymą perdirbant, laidojant sąvartynuose ir deginant. Analizės metu nagrinėjami ekologiniai rodikliai apima šiltnamio efektą sukeliančių dujų išmetimą, energijos suvartojimą ir kitas aplinkos poveikio kategorijas. Šis tyrimas atliktas naudojant SimaPro 9.4.0 duomenų bazę taikant IMPACT 2002+ metodą, o šio tyrimo išvados skirtos padėti būsto savininkams, politikos formuotojams ir pramonės suinteresuotiesiems subjektams priimti pagrįstus sprendimus dėl šildymo technologijų diegimo gyvenamuosiuose pastatuose. Išryškindama KDK ir OŠS poveikį aplinkai, ši gyvavimo ciklo analizė (GCA) prisideda prie vertingų įžvalgų pereinant prie tvarių ir efektyviai energiją vartojančių gyvenamųjų namų šildymo sprendimų ir energijos vartojimo mažinimo metodikų, kad būtų sumažinta žala aplinkai.
Reikšminiai žodžiai: gyvavimo ciklo analizė, kondensacinis dujinis katilas, oro šilumos siurblys, gruntinis šilumos siurblys, vandens šilumos siurblys, šiltnamio efektą sukeliančios dujos, karštas vanduo
Web-based idea management and Quadruple Helix networking of creative industry cohorts for COVID-19
Get PDFOn the one hand, web-based idea management platforms such as IdeaScale, Spigit, and BrightIdea can be used to facilitate the sharing of ideas and insights from existing EU and international cohorts of relevance to COVID-19. These platforms can be used to capture ideas from the experts, employees, public and other stakeholders (internal and external), and to facilitate the exchange of ideas and insights in a structured and organized way. On the other hand, Quadruple Helix networking can be used to facilitate collaboration and knowledge sharing between existing EU and international cohorts of relevance to COVID-19. This approach involves bringing together four key stakeholders – government, industry, academia, and civil society – to work together to develop solutions to the grand societal challenges posed by the pandemic. In this paper authors will fill the gap between web-based IMS practical application and theoretical framework of Quadruple Helix model to demonstrate potential benefits of merging of these elements. To bridge the gap systematic and analytical literature review will be done to create new Quadruple Helix web-based IMS framework and demonstrate it in action with case study taken from the creative industry. Aim of the research: potential of web-based idea management application in Quadruple Helix context in networking of existing EU and international cohorts of relevance to COVID-19. To reach the aim this research uses a combination of literature review, action-based research, and descriptive analysis to analyse the data and draw conclusions. Main conclusions: proves the potential of web-based IMS application with Quadruple Helix context. The application of the web-based IMS and Quadruple Helix approach is holistic and adaptable. Authors have created Quadruple Helix Adaptation in Idea Management Application Framework by including elements such as: Application elements includes: P1 is idea generation process, P2 is idea evaluation, P3 continuation of IM; Adaptation elements includes Quadruple Helix approach partners: Q1: universities, Q2: civilians; Q3: businesses; Q4: government
Mapping of organizational democracy: a bibliometric study
Get PDFSocial, 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
Assessment of the influence of stakeholders in the development of Lithuanian airports
Get PDFAir transport is the only way to reach Lithuania from abroad in the short and medium term. Despite a well-developed road network in the country, connections to other European capitals are long and inconvenient. 2014 July. Vilnius, Kaunas and Palanga airports were merged into one state-owned company, Lithuanian Airports (LTOU). Since then, the efficiency and overall profitability of LTOU operations have increased significantly. However, maintaining the airport’s current infrastructure is costly and needs upgrading and further investment. The company has repeatedly asked itself whether it can get more benefits by building one new Lithuanian airport or focusing on developing the existing three airports net. Stakeholders’ views and recommendations should be heard to make timely and appropriate decisions without a new airport’s technical and financial feasibility. An in-depth interview and secondary data analysis were selected for the empirical study. Thirteen employees of SE Lithuanian Airports and three of the Ministry of Transport and Communications of the Republic of Lithuania participated in the research. The following was used to analyse secondary data: SE Lithuanian Airport strategic plan, the material of strategic sessions, and a survey of the country’s population on the need for a new airport. The study found that stakeholders positively assess the long-term development projects of SE Lithuanian Airports, fully understanding the importance of airports and their contribution to the welfare of the state. Stakeholders can significantly impact results, so airport managers must consider whether they effectively involve stakeholders and, if not, how they can improve or encourage stakeholder involvement
Exploring the relationship between perceived organizational support and affective commitment among Saudi employees: the mediating effect of organizational trust
Get PDFDespite the acknowledged importance of perceived organizational support (POS), organizational trust (OT), and affective commitment (AC) for favorable organizational outcomes, relatively little is known about the processes that underlie these various associations, especially in Islamic, Arabian Middle Eastern contexts. This study aims to address this gap by exploring the relationships between POS and AC, and testing the mediating effect of OT in the Kingdom of Saudi Arabia (KSA). This study conducted a survey of 347 Saudi employees from a wide range of organizations, occupations, and industries and performed a hierarchical regression analysis. The results provided evidence of the validity of the three relevant constructs (POS, OT, AC) and the generalizability these constructs have outside of North American samples. It also indicated that POS is a significant predictor of OT, and both POS and OT were significant determinants of AC. The study also revealed that OT partially mediates the relationship between POS and AC. The findings contribute to a better understanding of the POS-OT-AC link in the Islamic Arabian context of the KSA. This study is among the first to test the mediating effect of OT on the POS-AC relationship, aiding the understanding of the indirect relationship between POS and AC
Barriers in adoption of FinTech by street vendors and hawkers in India using interpretive structural modeling
Get PDFThe adoption of financial technology (fintech) has the potential to make banking and financial services more accessible and convenient for all, but there are significant barriers preventing the adoption of fintech by street vendors and hawkers in India. This study aims to identify and analyse the barriers to fintech adoption using interpretive structural modelling (ISM). The research identified nine key barriers to fintech adoption, including perceived risk, lack of trust, lack of perceived benefit, social influence, lack of awareness, cash culture, lack of literacy, perceived ease of use, and lack of financial literacy. The study utilizes ISM to develop a hierarchy of these barriers and their interrelationships. The findings suggest that to promote the adoption of fintech, it is essential to build trust and awareness of fintech services through education and out-reach programs. This research provides a comprehensive understanding of the barriers to fintech adoption among street vendors and hawkers in India and offers insights into how these barriers can be overcomed. The study contributes to the development of strategies that can help promote the adoption of fintech among marginalized populations and advance financial inclusion in India
The effect of sustainable marketing analysis on purchasing decisions with buying intention as a mediation: evidence from zero waste shop in Indonesia
Get PDFThe rapid social change in the world through global economic turmoil, social inequality, and degradation of the natural context triggered an increase in criticism of the marketing approach oriented towards the dimension of profit alone. The concept of modern marketing requires rebranding with sustainability issues, namely the sustainable marketing model. Marketers must present to consumers an active and responsible management attitude and openness and honesty in market communication. This study aims to investigate the influence of the application of sustainable marketing on purchasing decisions in zero waste shops, where purchase intention is a mediator. The dimensions of sustainable marketing include customer solution, customer cost, communication, and convenience. Quantitative research was undertaken by distributing survey questionnaires via google forms online. A total of 193 respondents were obtained from distributing questionnaires in Jakarta. The data was analyzed using Structural Equation Modelling-Partial Least Square (SEM-PLS). The analyses have proven that sustainable marketing positively affects purchase intention and purchase decisions. Purchase intention has a positive effect on purchase decision dan has functioned effectively as a mediator between sustainable marketing and purchase decision. This study contributes to a long-term-oriented marketing strategy by looking at the dynamics of healthy lifestyle changes that must be done quickly