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Drabužių ilgaamžiškumo didinimas taikant ekologinio projektavimo, žiedinės ekonomikos ir atsekamumo vertės grandinėje strategijas.
No full textThe textile industry is one of the most impactful worldwide and there are numerous impacts during the value chain of clothing. One of the most significant ones is textile waste, which is mainly incinerated or landfilled. To tackle these and other challenges, the EU has developed the Ecodesign for Sustainable Products Regulation, introducing specific design requirements for various products put in the European market and the concept of the Digital Product Passport as a tool to enhance traceability and sustainability. The extension of longevity in clothing is a critical approach to slow down material flows and decrease environmental impacts. This work focuses on analyzing Ecodesign, Circular Economy and Traceability strategies for longevity extension of garments through the value chain and tackling the found gap in the downstream traceability. To do so, first, a literature review is prepared about these topics; then, semi-structured interviews with KTU experts are done during March and April of 2025. After classifying the longevity main strategies according to the stakeholder and life cycle phase, an LCA is performed, using SimaPro 9.5 and the ReCiPe 2016 method, for one polyester dress (0.478 kg), showing the differences between the baseline, which includes raw materials extractions, manufacturing, distribution, first use, collection, sorting and incineration as EoL, and different scenarios with variations across the whole life cycle stages. Results show that one polyester dress made with fiber-to-fiber recycled PET, in a sustainable manufacturing process and with extended use by re-purchase in a C2C platform, can decrease the environmental impact by 68%. DPP is proposed to be an integral tool that can help track garments after purchase and gather more accurate data about the use phase, allowing more precise LCAs to identify unknown hotspots. Further research needs to be done around this topic to find the best strategies to ensure long-lasting garments without compromission quality and their environmental performance
Environmental impact assessment of textile products using the life cycle assessment method.
No full textThe textile industry significantly impacts the environment, which has led to an increasing focus on product analyses using life cycle assessment methodologies. In this work, an environmental impact assessment was carried out on three types of T-shirts: cotton, polyester and blended fabrics. The analysis also includes additional elements such as thermal stickers. The inventory analysis was carried out based on defined system boundaries covering all stages of the life cycle. The assessment was carried out using the SimaPro 10.1.0.4 software, using the Environmental Footprint 3.1 method. The life cycle analysis covered all stages of the life cycle from raw material extraction to product disposal. Environmental impacts were assessed in 27 categories, of which 9 were analysed in detail. The analysis evaluated different scenarios related to the energy source – mixed or renewable electricity – and waste management – landfill or recycling. Analysis of the results showed that polyester T-shirts with a sticker had the highest impact on climate change when produced using mixed electricity and disposed of in a landfill. Their environmental impact was 6.35 kg CO₂/eq., while when mixed energy was replaced by renewable energy, this impact was reduced to 4.09 kg CO₂/eq. A large part of this impact is related to the use of fossil fuels in the extraction phase. Meanwhile, cotton T-shirts have a high water consumption, which is related to the need for irrigation during the cotton growing phase. Their climate change impact was lower at 1.65 kg CO₂ eq. with mixed electricity, while this was reduced to 0.996 kg CO₂ eq. with renewable energy. Mixed-composition T-shirts had intermediate results in most categories, but their environmental impact is due to their more complex recycling process. The climate change implications of changing the type of energy used changed only slightly from 3.32 kg to 3.22 kg CO₂ eq. Mixed materials are currently rarely recycled and their waste is more likely to be landfilled or incinerated, which may increase the impact in the long term. Uncertainty analysis using the Monte Carlo method showed that all scenarios with renewable energy and recycling are statistically more environmentally friendly than those with mixed energy and landfill. The analysis showed that the confidence intervals between the compared scenarios do not intersect, which confirms the reliability of the results and the stability of the analysis. Based on the analysis, recommendations are made. It suggests choosing lower impact materials, using renewable energy in production, increasing recyclability and extending the lifetime of products. It should also be mentioned that even minor components such as stickers should be included in the analysis as they have a significant impact in some environmental impact categories
Barriers to implementing the STEAM method in preschool education and possibilities for reducing them.
No full textToday, in the field of education worldwide, increasing attention is being given to the STEAM (Science, Technology, Engineering, Arts, Mathematics) approach, which integrates various disciplines and promotes holistic learning. In Lithuania, the application of this method in preschool education is both relevant and significant, aiming to develop children who are capable of solving problems, thinking creatively and critically, and adapting to a rapidly changing world. Although the STEAM methodology is already widely applied in various educational institutions, its integration into preschool education is relatively new. This requires specific methodological tools, teacher training, and infrastructure adaptation to effectively implement the method with young children. The main scientific issue addressed in this project is the barriers to implementing the STEAM methodology in preschool education and the possibilities for reducing them. These include both internal barriers, such as teachers' preparedness and methodological tools, and external ones, such as a lack of financial resources and insufficient parental involvement. The aim of the study is to identify the barriers to implementing the STEAM methodology in preschool education and to propose strategies for reducing them. The object of the study is the barriers to the implementation of the STEAM methodology in preschool education. Research objectives: 1)to reveal the theoretical aspects of the STEAM concept; 2) to justify the research methodology for identifying barriers to STEAM implementation in preschool education;3) to identify the barriers to STEAM implementation and justify strategies for reducing them in preschool education. The research was conducted using a quantitative method. A questionnaire was developed and distributed to preschool education institutions that apply the STEAM methodology and was also published online. The collected data were analyzed using the SPSS software. The results of the study showed that the main barriers include: a lack of financial resources, insufficient parental involvement, a lack of cooperation with business and academic institutions, a lack of feedback on STEAM activities, a shortage of methodological guidelines, insufficient preparation in applying technological literacy, and a lack of specialized training The recommendations provided include: budget review, organizing informational meetings, establishing partnerships, implementing feedback systems, developing methodological tools, conducting technological literacy training, and organizing seminars. These results can be used in educational institutions to more effectively apply the STEAM methodology and reduce barriers.The project consists of several main parts. The first part includes a literature review and theoretical background on the STEAM methodology. The second part focuses on the methodology of the empirical research and the analysis of the results. The third part provides recommendations and practical strategies for reducing barriers. The project concludes with findings and suggestions for future research
Synthesis, characterization, and biological activity evaluation of hydrazones from 3-[(4-ethoxyphenyl)amino]propanehydrazide.
No full textIn this work, new hydrazones were synthesised from the starting hydrazide and various substituted aromatic ketones and aldehydes. The starting material 3-[(4-ethoxyphenyl)amino]propanehydrazide was synthesised in two steps from 4-ethoxyaniline and methyl acrylate by treatment of the resulting intermediate ester with hydrazine hydrate. Reactions of 3-[(4-ethoxyphenyl)amino]propanehydrazide with substituted ketones and aldehydes bearing various heterocyclic moieties and functional groups in their structure were carried out, leading to different biological activity of the obtained products
Tert-butylcarbazole and methoxycarbazole substituted on the phenazine group exhibit mechano and thermoresponsivity for TADF LEECs /
No full textTwo new well-defined donor–acceptor–donor (D–A–D′) thermally activated delayed fluorescence (TADF) molecules with mechanochromic and thermochromic architectures were designed and synthesized based on tert-butylcarbazole and methoxycarbazole substituents attached to a phenazine derivative. Density functional theory (DFT) studies revealed molecular structures with extended π-conjugation and low singlet–triplet energy gaps (ΔEST), which enhance reverse intersystem crossing (RISC) for efficient TADF. Single-crystal X-ray diffraction confirms differences in molecular packing. The dye composed of tert-butylcarbazole exhibits lower aggregation and higher photoluminescence quantum yield (PLQY) upon spin-coating in a solid film, owing to its bulkier structure. Thermal stability studies demonstrated high decomposition temperatures (Td > 300 °C) and improved rigidity of the dye consisting of tert-butylcarbazole. Photophysical investigations revealed that the dyes dispersed in a tetrahydrofuran (THF):water mixture showed aggregation-induced emission enhancement (AIEE). Incorporation of the complex organometallic [Ir(buoppy)2(dmapzpy)]PF6 as a host in LEECs favors the energy transfer and yields single emission peaks at 588 and 587 nm with 60 wt % host content. The improved device attains maximum current (28.97 cd A–1), power (22.11 lm W–1), and external quantum efficiency (4.02%). These findings underline the significance of substituent design and host:guest interactions in improving TADF LEEC performance and provide new insights for high-efficiency optoelectronic devices
Comparative study of hardness evolution in 5754 aluminum welds under AC and DC welding currents /
No full textThis study examines how thermal and mechanical effects influence hardness distribution in 4, 6, and 8 mm AA5754 aluminum plates welded using TIG with AC and DC currents. Vickers hardness (HV0.01) was measured alongside tensile tests to evaluate weld performance. Results show that AC welding produces higher but more variable hardness, while DC welding yields more stable profiles. Notably, thinner plates (4 mm) showed minimal hardness differences between current types due to faster cooling. Strain hardening increased hardness up to 125 HV and reduced variation. The extent of hardness stabilization and heat-affected zone size depended on plate thickness. Although current type influenced hardness distribution, it had little effect on fracture toughness
Antimicrobial vitrimers synthesized from dipentaerythritol pentaacrylate and 2-hydroxy-3-phenoxypropyl acrylate for LCD 3D printing /
No full textIn this study, two monomers, dipentaerythritol pentaacrylate and 2-hydroxy-3-phenoxypropyl acrylate, were used to synthesize antimicrobial vitrimers with and without a transesterification catalyst and investigate their properties. The addition of the comonomer 2-hydroxy-3-phenoxypropyl acrylate to the photocurable resin reduced its viscosity and shrinkage but increased the gel point and reduced the brittleness and increased flexibility of the resulting polymers. All vitrimers exhibited self-welding and reprocessability properties and thermoresponsive shape memory, maintaining two permanent shapes. All vitrimers showed high antimicrobial activity against widely spread bacteria and fungal strains, including medically important ones. The resin, composed of dipentaerythritol pentaacrylate (1 mol) and 2-hydroxy-3-phenoxypropyl acrylate (10 mol), was applied to LCD 3D printing technology, and the Y-shaped connector was printed. In addition, the antimicrobial activity makes these vitrimers particularly important for use in areas with high microbial concentrations, such as medical facilities
Comparative analysis of perturbation techniques in LIME for intrusion detection enhancement /
No full textThe growing sophistication of cyber threats necessitates robust and interpretable intrusion detection systems (IDS) to safeguard network security. While machine learning models such as Decision Tree (DT), Random Forest (RF), k-Nearest Neighbors (K-NN), and XGBoost demonstrate high effectiveness in detecting malicious activities, their interpretability decreases as their complexity and accuracy increase, posing challenges for critical cybersecurity applications. Local Interpretable Model-agnostic Explanations (LIME) is widely used to address this limitation; however, its reliance on normal distribution for perturbations often fails to capture the non-linear and imbalanced characteristics of datasets like CIC-IDS-2018. To address these challenges, we propose a modified LIME perturbation strategy using Weibull, Gamma, Beta, and Pareto distributions to better capture the characteristics of network traffic data. Our methodology improves the stability of different ML models trained on CIC-IDS datasets, enabling more meaningful and reliable explanations of model predictions. The proposed modifications allow for an increase in explanation fidelity by up to 78% compared to the default Gaussian approach. Pareto-based perturbations provide the best results. Among all distributions tested, Pareto consistently yielded the highest explanation fidelity and stability, particularly for K-NN ((Formula presented.) = 0.9971, S = 0.9907) and DT ((Formula presented.) = 0.9267, S = 0.9797). This indicates that heavy-tailed distributions fit well with real-world network traffic patterns, reducing the variance in attribute importance explanations and making them more robust
