16168 research outputs found
Sort by
Investigation of edge banding resistance to heat and moisture in furniture manufacturing.
No full textEdge bands are used for finishing the edges of case furniture. They are especially important for furniture exposed to moisture and temperature-sensitive environments, such as kitchen and bathroom furniture. They give products an aesthetic appearance and protect them from environmental effects. Currently, European furniture manufacturers face rapidly growing competition from Asian countries. To maintain leading positions, Europe must actively search for new strategies to remain competitive. One way is to expand exports to distant regions with high humidity and temperature conditions. However, there is a lack of detailed studies analyzing edge bands' resistance to these environmental factors. It is important not only to test their durability, but also to optimize production costs, which could help reduce expenses. Determining the economically optimal thickness of edge bands would maintain a competitive advantage and ensure a balance between cost and quality. The purpose of this research is to investigate the effects of heat and humidity on edge bands in furniture manufacturing and to find the economically optimal thickness of edge bands that ensures the lowest costs without losing quality. The study uses medium-density particleboard (MDP) and acrylonitrile-butadiene styrene (ABS) edge bands, which are widely applied in the furniture industry and are known for their high resistance to environmental impacts. The bonding process employs ethylene-vinyl acetate (EVA) hot melt adhesive, applying traditional gluing technology. Experimental results showed that EVA adhesives and ABS edge bands are suitable for use under high temperatures and humidity. On the other hand, an even adhesive layer without microscopic gaps between the edge and the panel is a critical factor for ensuring resistance to moisture. It is worth noting, that attention should be paid not only to the edge band itself, but also to the surface it is applied to. A paper-laminated surface does not provide the same protection as a painted panel. It was found that the optimal edge band thickness, ensuring minimal production costs and maintaining necessary quality, is 0.8 mm. Thus, using an even adhesive application, suitable furniture finishes, and optimized ABS edge band thickness can ensure resistance to various environmental factors and achieve an efficient balance between quality and costs
On stability and convergence of difference schemes for one class of parabolic equations with nonlocal condition /
No full textIn this paper, we construct and analyze the finite-difference method for a two-dimensional nonlinear parabolic equation with nonlocal boundary condition. The main objective of this paper is to investigate the stability and convergence of the difference scheme in the maximum norm. We provide some approaches for estimating the error of the solution. In our approach, the assumption of the validity of the maximum principle is not required. The assumption is changed to a weaker one: the difference problem’s matrix is the M-matrix. We present numerical experiments to illustrate and supplement theoretical results
Comparative analysis of digital construction project management.
No full textThis paper presents a review of academic papers analysing the work of international researchers on digital projects and their evaluation. Digital projects have many advantages over traditional (physical or analogue) solutions. These advantages stem from their flexibility, scalability and the application of technology. Four digital projects are analysed in this thesis: 1) the overhaul of a part of Smėlynės Street in Panevėžys (from the railway crossing to the city boundary); 2) the overhaul of the Klaipėdos St., Projektuotojų St., Panevėžys, Dariaus ir Girėno St. intersection into a roundabout; 3) new construction of the link of J. Janonio St. with the Via Baltica bypass; 4) reconstruction of the intersection of J. Tilvyčio St., V. Alantas St. in Panevėžys into a roundabout. The project evaluation criteria were divided into three groups: design, organisation and construction. The evaluation criteria for the project were divided into three groups: organisation of design works and construction. In order to select the significance of the evaluation criteria, a survey questionnaire was presented with questions that would help to reveal the opinion of professionals on the use of wood composite beams for the installation of building slabs. The survey was carried out with 24 respondents, 89.8% of whom work in road construction and design and 10.2% in building construction and design. The multi-criteria methods TOPSIS and COPRAS will be used. After the survey, the significance of the criteria has been established and the agreement of the expert survey has been calculated. It was found that the expert survey is concordant at all stages, with a concordance coefficient of 0,756÷0,908. The calculation of the total efficiency scores by TOPSIS method showed that the most efficient project among the selected ones is the reconstruction of the intersection of J. Tilvyčio St., V. Alantas St. in Panevėžys into a roundabout, with a total efficiency of 2.546 points. The second most efficient is the reconstruction of the intersection of Klaipėdos St., Projektuotojų St., Dariaus ir Girėno St. in Panevėžys into a roundabout, with a cumulative efficiency score of 1.704. The third is the new construction of the J. Janonio Street link to the Via Baltica bypass: its overall efficiency score is 1.496. The least efficient is the major repair of the part of Smėlynės Street in Panevėžys (from the level crossing to the city boundary). This project has a cumulative efficiency score of only 1.346. The calculation of the total efficiency percentages using the COPRAS method shows that the most efficient project among the selected ones is the reconstruction of the intersection of J. Tilvyčio St., V. Alantas St. in Panevėžys into a roundabout, with a total efficiency of 30%. The second most efficient is Klaipėdos St., Projektuotojų St. in Panevėžys, The third is the new construction of the J. Janonio Street link to the Via Baltica bypass: its overall efficiency is 24%. The least efficient is the overhaul of the part of Smėlynės Street in Panevėžys (from the railway crossing to the city boundary): the overall efficiency of this project is only 21%
Bioactive component integrated textiles: a promising source of medicine and healthcare /
No full textThe healthcare industry can greatly benefit from natural colorants as bioactive component integrated textiles. These textiles are perfect for use in healthcare because they are biocompatible, have antimicrobial characteristics and are sustainable. It is an exciting new development that might replace harmful synthetic dyes with safer and more practical options for healthcare textiles. The use of bio-colorants in textiles makes them both biocompatible and antimicrobial. By facilitating quicker healing and warding off infections, these textiles further add to improved healthcare outcomes. It also helps fund research into smart clothes that can track vital signs to better care for patients. Incorporating biocolorants into textiles is the focus of this review paper which will also examine different sources of bio-colorants and fabrication methods. In addition, the review work will discuss obstacles and future possibilities for bio-colorant technology advancement in the healthcare and textile sectors. Developing smart textiles that monitor health parameters, improving wound dressings with biocompatible and healing properties and creating antimicrobial fabrics for surgical garments and hospital linens are all potential uses for bio-colorant integrated textiles. Patients can wear these textiles to protect themselves from harmful ultraviolet rays and these materials could also find use in environmentally friendly medical supplies
Research on the use of wood processing waste in concrete.
No full textThe objective of the master’s thesis is to produce wood-concrete biocomposites using 0/5 mm fraction wood processing waste and mineral binders and to determine the physical and mechanical properties of the resulting biocomposites. The master's thesis consists of 3 separate parts: literature analysis, research methodology and research results and discussion. The literature analysis part identifies the shortcomings of the use of organic materials in the production of biocomposites, possible physical and chemical solutions, and reviews the technology for the production of lightweight artificial aggregates. The research methodology part describes the materials used in the research, the compositions of lightweight artificial aggregates and biocomposites with lightweight artificial aggregates, the applied studies, and the course of the research. The research results and discussion part present the results of the research, indicates the physical and mechanical properties of lightweight artificial aggregates, describes the physical and mechanical properties of biocomposite samples with lightweight artificial aggregates, and provides calculations of the CO2 footprint. The research has shown that the use of lightweight artificial aggregate in the production of biocomposites has a negative impact on the compressive strength, shrinkage deformations, and frost resistance properties of biocomposites. Products with lower density are also obtained. However, the use of lightweight artificial aggregate has a positive impact on reducing the CO2 footprint. The results obtained in the final thesis can be used in further research into biocomposites with a lower CO2 footprint. The volume of the master's thesis is 72 pages without appendices, 26 tables and 38 figures. 66 literary sources were used in the master's thesis
Analysis of the efficiency of construction project management software.
No full textIn the scientific literature analysis section, foreign scientific articles related to construction project management, software, and methods aimed at efficiently meeting project deadlines are reviewed. The analysis examines proposals and software designed to complete construction projects on time, without depleting resources or incurring penalties. The methodological section reviews multi-criteria evaluation methods, their advantages and disadvantages, as well as the formulas required for calculations. The methods selected for the research are also discussed. The research section investigates four software tools aimed at facilitating construction project management, ensuring timely completion of projects while utilizing optimal resources and funding. For this research, an expert survey was conducted to identify the key aspects influencing the selection and practical application of software. The survey results are used to determine the significance coefficients, which are then applied in the MOORA and TOPSIS multi-criteria evaluation methods. Their similarities and differences are observed. For the multi-criteria evaluation, four software tools are selected: Microsoft Project, Smartsheet, PlanGrid, and Primavera P6 (Oracle), along with five evaluation criteria: along with five evaluation criteria: the annual cost of the software, ease of use, adaptability and flexibility, storage and retrieval of information from the cloud instead of a local drive, and compatibility of the software with existing systems. A decision-making matrix is formed based on these criteria. The results of the multicriteria evaluation methods are presented in diagrams. Research Object - analysis of the efficiency of construction project management software. Aim of the Work – to analyze the characteristics of selected project management software and determine which system is the most efficient. Objectives of the Work: 1. To review scientific literature and identify factors leading to unsuccessful construction project management processes. 2. To analyze and characterize multicriteria analysis methods, justifying the application of MOORA and TOPSIS methods for processing research data. 3. To select and describe the evaluation criteria for the compared construction project management software, assess its efficiency, and compare the results obtained from different analysis methods. Research Methods - analysis of scientific articles. Published Article: Juozaitis, D., & Kelpšienė, L. Evaluation of the Efficiency of Construction Project Management Software Using the TOPSIS Method. Presented at the student scientific conference “Technological and Business Trends 2024” on November 22, 2024, Panevėžys. The master's thesis consists of: summaries in Lithuanian and English, an introduction, three chapters, conclusions, and a list of references. The thesis comprises 70 pages
Hydration and mechanical properties research of concrete with ultra low content of cement.
No full textThe aim of the Master's thesis is to develop a new generation of concrete with a significantly reduced amount of Portland cement in order to reduce CO2 emissions of standard concrete formulations and to create a more environmentally friendly concrete formulation. The master 's final project consists of four parts: the analysis of the literature, the materials used in the research, the experimental methods and the results. The literature review provides an overview of the types of glass and their chemical composition. The possibility of using waste glass as a pozzolanic material and the risk of alkaline corrosion are investigated. The cases of how these risks can be managed or avoided are analysed. The CO2 emissions of replacing cement with glass are also compared. The section on materials used in the studies presents the materials used in the studies. The experimental methods section describes the methods used to test the samples. The experimental results section examines the influence of ground glass on the hydration of Portland cement and analyses the process of ground glass production. The physical and mechanical properties of the new concrete compositions, such as material density, compressive strength, shrinkage and expansion deformations, are determined. Studies on water absorption, porosity and resistance to freeze–thaw cycles were carried out. The environmental effects of the new compositions were evaluated and compared with standard concrete compositions
Investigation of sustainable concrete with different binders and shrinkage reducing admixtures.
No full textConcrete is the most used building material in the world, with production increasing year on year. It plays a significant role in modern construction due to its versatility in shaping, durability, and cost-effectiveness. However, the production of cement used for concrete is highly polluting due to the large amount of carbon dioxide emitted into the atmosphere. The aim is therefore to use sustainable concrete, for which the cement used is supplemented with a certain amount of additives or substitutes to reduce the clinker content. One such additive is opoka. Such concrete with opoka cement has the property of having higher shrinkage deformations at an early age, leading to cracks and fissures. To overcome this problem, chemical admixtures or other additives are used in concrete production to reduce the shrinkage of the concrete. Master‘s final project aim is to investigate the effect of concretes with different binders on the properties of fresh and hardened concrete. The focus is on the study of early and typical shrinkage. The object of the studies is a concrete mix with all the same ingredients and quantities, except for the amount of superplasticizer (to achieve the same slump class for each mix) and the type of binder. An experimental study is carried out to produce four different concrete compositions. Two of them are formulated with a binder containing pozzolans, a type of opoka. The Master's final project consists of three parts. The first part is a literature review, which provides an overview of similar types of research. The second part describes the research methodology, which includes the standards to which the tests are carried out, a description of the materials used and the design of the concrete composition. The third part presents and summarises the results of experimental studies
Visuomenės palaikymas klimato kaitos politikai: tarptautinė ES šalių palyginamoji perspektyva.
No full textAddressing climate change requires public support for various policy measures. This study investigates public attitudes toward climate change policies in five countries: Lithuania, Finland, Spain, Germany, and Hungary. The fact that climate change is an anthropogenic phenomenon is not a new fact for governments; the EU is putting a great effort at climate change mitigation and adaptation since the European Parliament (EP) and European Commission are working on climate policy that must be implemented by the European Union countries, Lithuania, Germany, Finland, Spain, and Hungary included (European Commission, 2021). However, different CC policy measures have different support in separate European regions. Thus, this study analyses theoretical approaches to different policy measures: command-and-control, economic-based, information based and voluntary based policy measures; these measures are applied in the quantitative analysis as well. The novelty of this research lies in its cross-national, data-driven approach to understanding public support for climate change policies in Europe. By integrating comparative analysis of climate policies with empirical data from the ISSP "Environment" module (2020-2022), this study provides a comprehensive and comparative view of climate policy support across diverse socio-political contexts. This study aims to provide a comparative understanding with a focus on factors influencing support for climate change policies across different EU contexts. The results of the research have shown that command-and-control policies, particularly the reduction of protected nature areas for economic growth, are largely opposed by the public in all countries, with Germany and Finland being the most resistant, and Hungary showing the highest acceptance. Economic-based measures such as paying higher taxes, prices, and reducing standards of living receive the strongest support in Germany and Finland, likely due to their economic stability, while Lithuania and Hungary exhibit the greatest resistance. Informational policies reveal that Hungary and Lithuania place the highest trust in science but are the most skeptical about society's ability to act on climate challenges. Conversely, citizens of Germany, Spain, and Finland show greater optimism about collective action. Voluntary measures find the highest support in Germany, Finland, and Spain. However, Lithuania and Hungary lag significantly, likely due to economic constraints and limited environmental engagement opportunities. Gender and education emerge as critical factors, with women consistently showing higher environmental concern and support for climate action, especially in Germany, Finland, and Spain. Higher education is associated with stronger backing for economic and voluntary policies, particularly in Finland, Germany, and Lithuania, although this correlation varies across regions. In conclusion, Germany, Finland, and Spain are leaders in public support for CC policies, showing proactive engagement and willingness to adapt for a sustainable future. Conversely, Lithuania and Hungary require greater efforts to strengthen public support, address economic challenges, and increase awareness of climate action
Piliečių vaidmuo įgyvendinant visuotinės gynybos principą Lietuvoje.
No full textAs geopolitical situation intensified in Europe, the principle of total defence has been embraced as a national defence policy that involves citizens together with other sectors of the country into defence capabilities. Instead of relying on its military and NATO allies, Lithuania, a young democracy is one of those countries which implemented total defence principle. This master’s project explores the role of citizens in the implementation of total defence in Lithuania focusing on citizen participation in civil resistance. The topic demonstrates relevance as it addresses the need to understand the role of citizens in Lithuania’s total defence in the face of emerging geopolitical threats. At the same time, the project shows novelty as it focuses on Lithuania’s implementation of the Strategy for Preparing Citizens of the Republic of Lithuania for Civil Resistance, providing a thorough analysis of citizen involvement in defence policy and filling a gap on total defence application in young democracies such as Lithuania. The research problem is formulated as follows: development and challenges of the role of citizens in the implementation of total defence principle in Lithuania. The main research object is the role of citizens in the implementation of total defence principle in Lithuania while the aim of the project is to evaluate the involvement of citizens and define the progress of civil resistance strategy in the implementation of total defence principle in Lithuania. The project composed four objectives to reach the aim of the research which are (1) to analyse a theoretical framework of the role of citizens in the implementation of total defence, (2) to explore the context and the legal environment of citizen involvement in the implementation of total defence in Lithuania, (3) to define the involvement of citizens in the implementation of total defence principle in Lithuania based on strategic documents and (4) to identify the progress of citizen involvement in the implementation of total defence principle in Lithuania. The project used qualitative research methodology consisting of a systematic literature review of defence policies in Nordic countries and Switzerland and a contextual analysis of Lithuania’s legal environment of citizen involvement in defence policy implementation. Moreover, secondary data from annual governmental reports and public opinion surveys were used to complement the insights of eight conducted interviews with subject matter experts. The key findings of the research reveal that Lithuania integrated its citizens into the national defence through the principle of total defence in the current political background. The small country took measures similar to the examples from the Nordics and Switzerland and addressed national challenges by strengthening its overall defence posture, increasing resilience and deterring possible enemy. Conducted theoretical framework indicated that the application of total defence and specifically the focus of including citizens provide them the role within defence capabilities and assure collective preparation for civil resistance during peacetime. Equally important is to define the role of citizens and their involvement in countries’ normative and strategic documents, however, as research found, limitations emerge when it comes to the inclusion of ethnic minority groups into building resilience and preparing these citizens for civil resistance. While it is important to define the roles for ministries and organisations such as the Lithuanian Riflemen’s Union (LRU) when implementing the Strategy too, the paper finds that it is crucial to employ civil society organisations, especially, NGOs who too educate and train citizens for civil resistance. The inclusion of NGOs into the implementation of the Strategy can substitute the personnel shortages experienced by Mobilisation and Civil Resistance Department (MCRD) and LRU. Nevertheless, Lithuania demonstrates commitment and progress when implementing the Strategy for Preparing Citizens of the Republic of Lithuania for Civil Resistance, however, the implementation of the Strategy appears to be focused mainly on the Ministry of National Defence and LRU. Other bodies such as the Ministry of Social Security and Labour (SOCMIN) on the other hand lack attention and funding to raise people’s participation in voluntary and community bond activities which greatly contribute to strengthening resilience of the country, therefore, there is a need to allocate resources for other ministries to perform their tasks when implementing the Strategy and possibly involving NGOs to help SOCMIN to achieve its goals. If Lithuania addresses these limitations, it can serve as a model to other countries throughout Europe who seek to involve their citizens into national defence by applying the principle of total defence. The project consists of 63 pages, 15 tables, 13 figures and two appendices. The project used 49 sources of scientific literature and 35 information sources