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CE management /
No full textThis chapter presents a deep discussion of the recent case studies on implementation of best practices and strategies for the circular economy, and an integrated approach to CE management in the built environment. The case studies were evaluated by the following aspects: Design for Circular Economy; Resource Optimization; Collaborative Approaches; Digital Technologies; Policy and Regulatory Frameworks; Consumer Engagement; Life Cycle Assessment; Circular Business Models; Smart Monitoring and Evaluation; Stakeholder Collaboration. These studies indicated the diversity of best practices in CE management in different fields. On the other hand, a strategic planning and collaborative development of circular practices with relevant stakeholders are crucial for the effective development and implementation of circular capabilities and initiatives in the built environment
Two-dimensional transition metal dichalcogenide: synthesis, characterization, and application in candlelight OLED /
No full textLow-color-temperature candlelight organic light-emitting diodes (OLEDs) offer a healthier lighting alternative by minimizing blue light exposure, which is known to disrupt circadian rhythms, suppress melatonin, and potentially harm the retina with prolonged use. In this study, we explore the integration of transition metal dichalcogenides (TMDs), specifically molybdenum disulfide (MoS2) and tungsten disulfide (WS2), into the hole injection layers (HILs) of OLEDs to enhance their performance. The TMDs, which are known for their superior carrier mobility, optical properties, and 2D layered structure, were doped at levels of 0%, 5%, 10%, and 15% in PEDOT:PSS-based HILs. Our findings reveal that OLEDs doped with 10% MoS2 exhibit notable enhancements in power efficacy (PE), current efficacy (CE), and external quantum efficiency (EQE) of approximately 39%, 21%, and 40%, respectively. In comparison, OLEDs incorporating 10% of WS2 achieve a PE of 28%, a CE of 20%, and an EQE of 35%. The enhanced performance of the MoS2-doped devices is attributed to their superior hole injection and balanced carrier transport properties, resulting in more efficient operation. These results highlight the potential of incorporating 2D TMDs, especially MoS2, into OLED technology as a promising strategy to enhance energy efficiency. This approach aligns with environmental, social, and governance (ESG) goals by emphasizing reduced environmental impact and promoting ethical practices in technology development. The improved performance metrics of these TMD-doped OLEDs suggest a viable path towards creating more energy-efficient and health-conscious lighting solutions
Accuracy of digital and conventional implant impressions in edentulous jaws: a clinical comparative study /
No full textOBJECTIVES: This clinical study aimed to evaluate the accuracy of digital and conventional implant impressions in a fully edentulous maxilla and mandible.
METHODS: A 53-year-old edentulous patient with four maxillary and two mandibular implants was selected. Ten intraoral scans (IOS) and a conventional impression per jaw were taken. Clinically verified upper and lower plaster models were digitized using both optical (reference data, n=10 per model) and tactile laboratory scanner (n=10 per model). Accuracy was evaluated by comparing the precision and linear/angular deviations of the implants with the reference data. Statistical analyses were conducted using Student's t-test and Kruskal-Wallis test (α=0.05).
RESULTS: In the maxilla, the most significant linear deviations exceeding the 100 µm threshold were found with IOS between implants 1-4. In the mandible, all linear deviations remained below 55 µm. Angular deviations between implants after IOS ranged from 0.01° to 0.40° in the mandible and <0.01° to 1.86° in the maxilla. After tactile scanning, linear deviations did not exceed 100 µm threshold (except in one distance) and angular deviations ranged from 0.04° to 0.54° (mandible) and <0.01° to 2.50° (maxilla). The optical scanner demonstrated significantly higher precision (p < 0.001) compared to the IOS and tactile scanner.
CONCLUSIONS: Given the significant deviations observed, especially in the maxilla, the optical scanner following conventional impressions remained the preferred method for fully edentulous cases due to its superior accuracy.
CLINICAL SIGNIFICANCE: IOS could be a viable alternative particularly for shorter distances in the edentulous jaw, although the clinical implications of these deviations need to be investigated in future studies
Analysis of the experiences in implementing the participatory budgeting in Kaunas district municipality.
No full textThe increasing focus on citizen involvement in decision-making is giving rise to a growing number of new forms of citizen participation and tools for building trust and accountability in public authorities and promoting democracy. One of the tools that encourages citizens to take an active part in decisions affecting their local area is the participatory budget. Strengthening democratic processes is crucial in democracies, and participatory budgeting is an excellent tool for citizens to take over the decision-making power of certain decisions. Participatory budgeting is a dynamic process that is usually adapted to the specific needs of local communities (Boc, 2021). The implementation of projects proposed and won by local citizens through the participatory budget process increases their positive experiences, which improves the involvement of local citizens in the decision-making process and promotes trust in local government by sharing responsibility for the allocation of the budget together. Most scholars analyse the benefits of participatory budgeting, its impact on citizens' involvement in decision-making and community development (Brun-Martos & Lapsley, 2017; Schugurensky & Mook, 2024), but there is a lack of in-depth analysis on the experiences of implementing participatory budgeting, i.e. on the benefits obtained and the challenges faced, especially in Lithuania. This final project analyses the experiences of participatory budgeting in Kaunas District Municipality, the analysis of which can significantly contribute to a more effective implementation of participatory budgeting in Lithuania. The research problem is: what are the benefits and challenges of implementing participatory budgeting in Kaunas District Municipality? The object of the study is the benefits and challenges of implementing participatory budgeting. The aim of the project is to examine the experience of implementing participatory budgeting in Kaunas district municipality in order to identify its benefits and challenges. The objectives of the project are as follows: 1) to carry out a theoretical analysis of the benefits and challenges of implementing participatory budgeting; 2) to examine the international and national legal frameworks and good practices of implementing participatory budgeting; 3) to carry out a research on the experiences of implementing participatory budgeting in Kaunas District Municipality. The research was based on the analysis of scientific literature, analysis of secondary data, content analysis of strategic documents and legal acts, theoretical modelling, qualitative research – semi-structured interviews, qualitative content analysis. The research sample consisted of seven informants – local residents involved in the participatory budgeting process, who submitted the project proposal, and Kaunas District Municipality employees directly involved in the participatory budget instrument. The study found that each stage of the participatory budgeting process has its benefits and challenges. The implementation of the participatory budget instrument in Kaunas District Municipality increases the participation of local residents in the decision-making process and promotes participatory democracy. Social justice, trust in government, and dialogue between local residents are enhanced. The surveydata revealed that the main challenge faced is unforeseen technological barriers. Although the implementation of participatory budgeting in the municipality faces some challenges, there is an analysis of the challenges and continuous improvement. After the analysis of the empirical research results, conclusions are drawn and recommendations are made to the Ministry of the Interior of the Republic of Lithuania, the Kaunas District Municipality Administration, the local population of Kaunas District, and the researchers studying the participatory budget. The project consists of three parts: a theoretical analysis of the benefits and challenges of implementing participatory budgeting, an analysis of the international and national legal framework for implementing participatory budgeting, and a study of the experiences of participatory budgeting in Kaunas District Municipality
The utilization of beta-phosphogypsum in building materials by using the casting and the press-forming processing methods.
No full textThe master's thesis analyzes beta-type phosphogypsum material from the waste landfill of the phosphate fertilizer company "Lifosa" in Kėdainiai. After conducting this study, the composition of beta-type phosphogypsum material from the waste landfill of the phosphate fertilizer company "Lifosa" in Kėdainiai will be known. This will allow us to see what mineral and chemical elements are in the composition of the phosphogypsum from this landfill and will provide an opportunity for Lithuanian scientists to compare it with alpha-type phosphogypsum from the same fertilizer company. Also, during this study, several forming methods will be performed, which will allow us to study the mechanical properties of this material. One of these forming methods is being tested in a completely new way, which creates the opportunity to discover a new alternative for forming samples. Thus, after studying all these areas, with the available data, it will be possible to continue scientific research in order to raise the use of phosphogypsum to a new higher level in the construction industry. During the final work, the chemical and mineral composition of the material, as well as the physical and thermal properties of the material were analyzed through various studies and analyses. In the work, samples were produced using casting and press-forming methods and their mechanical properties were studied. Based on the obtained strength results, the possibilities of using this material in the production and processing of building materials were examined
Research of UV resistance and physical-mechanical properties of thermally treated wood.
No full textMaster‘s thesis aims to investigate the influence of hydrothermal and thermal treatment in oil on construction wood's physical, mechanical, and UV resistance properties. The aim of the work is implemented through the 5 work tasks, which include literature analysis, heat treatment of samples by changing the temperature regime and agent, and research on physical, mechanical and UV resistance properties. The literature analysis discusses wood's structure, chemical composition, physical and mechanical properties, the effects of thermal, hydrothermal, and thermal oil treatment on wood, and the possibilities of using treated wood. The experimental part describes the research equipment and the research process. During the study, wood samples were hydrothermally treated at different temperature regimes in an autoclave, and thermally in oil under open conditions. The following altered wood properties were observed: dimensional stability, physical properties, mechanical properties, resistance to biological factors, and changes in surface structure
Vibration analysis of hybrid thin floor slabs with CLT penels.
No full textThis MSc thesis examines thin hybrid slabs for administrative buildings using oscillation analysis. It evaluates the performance of hybrid slabs comprising CLT panels with additional concrete layers for ultimate (ULS) and serviceability (SLS) limit states, focusing on vibration analysis. The impact of increased concrete layers, enhancing stiffness and weight, on modal and response factor analysis is studied. The primary focus is on CLT200 L5s and CLT260 L7s slabs, determining optimal spacings through analytical design and finite element analysis using Robot Structural Analysis. The difference in utilization of slab panels is determined by comparing analytical design for ULS and SLS deflection limit states with vibration analysis conducted using the finite element method-based software "Robot Structural Analysis."
Research of physical and mechanical properties of CO2 cured cementless pavement elements.
No full textThe aim of the master's thesis is to create a cement-free carbonized product and determine its physical and mechanical properties as a paving element according to the testing methods for concrete outdoor paving stones specified in the LST EN 1338 standard. 3 tasks were set to achieve the aim of the thesis. The thesis consists of three main parts: literature analysis, research methodology and research results. The literature analysis part describes the CO2 curing technology, accelerated carbonization methods, the influence of binders and materials on carbonization, as well as the physical and mechanical properties of carbonized products, their CO2 gas emissions and the production technology of pressed products. The research methodology part describes the materials used, the composition of the samples, and their production process. The course of the research methods is also described and the formulas used to calculate the results are presented. The research results part describes and analyses the results obtained during the research. First, according to the compressive strength of the samples and the depth of carbonization, the composition that showed the best indicators was selected, which was further improved and studied by the tests described in the research methodology section. The physical and mechanical properties of the most optimal composition were determined and its CO2 gas absorption rate was calculated. The master's thesis is summarized in 7 conclusions. The volume of the thesis is 51 pages, the work contains 35 figures, 5 tables and 48 references
Usage of the image degradation process in electronic music composition.
No full textThe master thesis explores intentional degradation of digital images and their transformation into musical works by converting pixel data into MIDI information. The process involves analyzing the images pixel-by-pixel, mapping RGB values to musical notes and creating separate MIDI tracks for each color channel (red, green, blue). The study investigates how image compression affects the structure of the music and the melodic information. The aim of the work is to develop a system to write a musical composition using the notes obtained after converting the degraded image pixels into MIDI information. The initial concept of the project - to write a musical composition based on the conversion of one numbering system to another - was inspired by the work of Domas Vaivada, a 2023 graduate student of KTU, titled "Application of the PI number in electronic music composition", which presents a system of conversion of the decimal numbering system to the duodecimal numbering system, and the use of the PI number for the application of PI numbering to the electronic music composition. In order to extend the capabilities of the proposed system, a new system using pixel RGB values converted to a MIDI 128-note range was developed in this work. The conversion process involved masking the most significant bit of each RGB channel, matching with a 7-bit MIDI system, and creating separate MIDI tracks for red, green, blue and a combination of all three colors. One of the problems the project addresses is that a generated set of sheet music is not yet a piece of music, so a system has been developed to solve this problem. Each RGB channel is associated with specific roles: the red one with the rendering of natural sounds, the green and blue ones with the creation of a sense of rhythm, and the combined one with the reproduction of the bass line. To highlight the subtext of the piece, the music uses a combination of natural and synthetic sounds, starting with harmonious natural elements such as birdsong and ocean waves. Over time, these are replaced by mechanical sounds such as the clacking of keyboards and the ticking of clocks, conceptually reinforcing the symbolic intrusion of technology. The progression of the work reflects the stages of development and decline of society. Starting with a soundscape of nature, the musical composition develops the idea through eight stages of civilization: the emergence of a new civilization, stability, early growth, prosperity, transcendence, hubris, totalitarianism and collapse. To consolidate the organic structure and natural cycles, the Fibonacci sequence was integrated into the MIDI note layout of the theme. Effects such as distortion and reverberation add to the sense of bass line intensity. The cycle of musical pieces generated from different stages of degradation reflects how the interaction between technology, art and nature can lead to introspection about humanity's degradation trajectory towards chaos, away from our organic connection to the environmental order
Comparison of continuous-time partial Markov chain construction by heuristic algorithms for purpose of approximate transient analysis /
No full textWe investigate the construction of a partial absorbing continuous-time Markov chain (CTMC) using a heuristic algorithm aimed at approximate transient analysis. The accuracy of transient state probabilities is indicated by the probability of absorbing state(s) at the specified time moment. A key challenge is the construction of a partial CTMC that minimizes the probability of reaching the absorbing state(s). The generation of all possible partial CTMCs is too computationally demanding, in general. Thus, we turn to investigation of heuristic algorithms that chose to include one state at a time based on limited information (i.e., the partial chain that is already constructed) and without any assumptions about the structure of the underlying CTMC. We consider three groups of such algorithms: naive, based on state characterization by the shortest path (obtained by Dijkstra method) and based on exact/approximate state probabilities. After introducing the algorithms, we discuss the problem of optimal partial CTMC construction and provide several examples. Then we compare the algorithm performance by constructing the partial CTMCs for two models: car sharing system and a randomly generated CTMC. Our obtained numerical results suggest that heuristic algorithms using state characterization via the shortest path offer a balance between accuracy and computational effort