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The effect of proximity on risk perception: a systematic literature review /
No full textThe use of geospatial analytical tools has recently advanced risk perception research, with growing interest in spatial dimension. Available reviews of risk perception studies usually focus on specific types of risk or look at various socio-psychological, cognitive and cultural factors, and there are no systematic reviews of empirical research analysing the effect of proximity on risk perception. This article synthesizes the evidence from 81 empirical studies that investigate the significance of proximity on subjective risk perception. The systematic review focused on summaries of research methods, samples, geographic coverage, measurements and direction of influence of proximity variables on risk perception and types and sources of risk. The majority of the studies analysed implemented quantitative research. The most popular data collection methods were face-to-face interviews and postal surveys, but only half had representative samples. Studies looking into the effect of proximity on risk perception most often analysed environmental and technological risks. Two-thirds of the empirical studies found a significant impact of proximity on risk perception; the majority of these showed a positive correlation, with respondents living closer to hazards having higher risk perceptions. Negative correlations of risk perception with proximity are more characteristic of nuclear risks. Co-occurrence analysis of sources-of-risk and objects-at-risk has identified three most frequent clusters: impact of floods on economic properties; impact of other natural hazards on economic properties and impact of industrial facilities on health and lives
A novel approach for high-resolution coastal areas and land use recognition from remote sensing images based on multimodal network-level fusion of SRAN3 and lightweight four encoders ViT /
No full textLand use land cover classification from satellite images (remote sensing) has shown many efforts from the last decade due to ecological surveillance, rapid urbanization, law enforcement, climate change, agriculture drought, and disaster recovery. The low-resolution remote sensing images impact on the accurate prediction; therefore, the high-resolution deep learning architecture is widely required. This article proposes a new deep network-level fusion approach that merges a Stacked Residual Self-Attention CNN (SRAN3) with a lightweight ViT based on 4-encoders to enhance the model performance while reducing computational costs. The SRAN3 model is proposed for extracting sophisticated prominent features, while the 4-encoder-based ViT facilitates effective learning with reduced computation time. These networks are fused using a depth concatenation approach that effectively integrates the strengths of both architectures. The fused model hyperparameters are selected through Bayesian Optimization (BO), significantly improving the learning process. The trained model is later utilized in the testing phase, extracting features from the depth-concatenation layer. The extracted features are fed to neural network classifiers and obtain the final prediction. Two publicly available datasets, EuroSAT and NWPU_RESIS45, are employed to obtain improved testing and validation accuracy. The proposed SRAN3+WNN (Wide Neural Network) and 4-encoder ViT+WNN obtained 96.9% and 92.6% of accuracy; however, the proposed fused network+WNN achieved the highest accuracy of 98.4% on EuroSAT and 94.7% accuracy on the NWPU_RESIS45 dataset, respectively. Also, the proposed fused model interpretation is performed using the explainable artificial technique (XAI), which has shown improved land use and land cover classification
An analytical model for the steady-state thermal analysis of façade-integrated PV modules cooled by a solar chimney /
No full textThis paper proposes a steady-state thermal model for the passive cooling of photovoltaic (PV) modules integrated into a vertical building façade by means of a solar chimney, including an empirical correlation for turbulent free convection from a vertical isothermal plate. The proposed analytical model estimates the air velocities at the inlet and at the outlet of the ventilation channel of such a cooling system and the average temperature of the façade-integrated PV modules. A configuration composed of a maximum of six vertically installed PV modules and one solar chimney is considered. The air velocities at the inlet and at the outlet of the ventilation channel obtained for the case of installing PV modules on the building façade are compared with those calculated for the case where the PV modules are integrated into the roof with a slope of 37°. By comparing each of the solutions with one PV module to the corresponding one with six PV modules, it was found that the increase in the air velocity due to the effects of the solar irradiance and the height difference between the two openings of the ventilation channel ranges between 41.05% in the case of “Roof” and 141.14% in the case of “Façade”. In addition, it was obtained that an increase in the solar chimney height of 1 m leads to a decrease in the average PV section temperature by 1.95–7.21% and 0.65–2.92% in the cases of “Roof” and “Façade”, respectively. Finally, the obtained results confirmed that the use of solar chimneys for passive cooling of façade-integrated PV modules is technically justified
Evaluating the potential for underground hydrogen storage (UHS) in Lithuania: a review of geological viability and storage integrity /
No full textThe aim of this study is to review and identify H2 storage suitability in geological reservoirs of the Republic of Lithuania. Notably, Lithuania can store clean H2 effectively and competitively because of its wealth of resources and well-established infrastructure. The storage viability in Lithuanian geological contexts is highlighted in this study. In addition, when it comes to injectivity and storage capacity, salt caverns and saline aquifers present less of a challenge than other kinds of storage medium. Lithuania possesses sizable subterranean reservoirs (Cambrian rocks) that can be utilized to store H2. For preliminary assessment, the cyclic H2 injection, and production simulation is performed. A 10-year simulation of hydrogen injection and recovery in the Syderiai saline aquifer demonstrated the feasibility of UHS, though efficiency was reduced by nearly 50% when using a single well for both injection and production. The study suggests using separate wells to improve efficiency. However, to guarantee economic injectivity and containment security, a detailed assessment of the geological structures is required specifically at the pore scale level. The volumetric approach estimated a combined storage capacity of approximately 898.5 Gg H2 (~11 TWh) for the Syderiai and Vaskai saline aquifers, significantly exceeding previous estimates. The findings underscore the importance of detailed geological data and further research on hydrogen-specific factors to optimize UHS in Lithuania. Addressing technical, geological, and environmental challenges through multidisciplinary research is essential for advancing UHS implementation and supporting Lithuania’s transition to a sustainable energy system. UHS makes it possible to maximize the use of clean energy, reduce greenhouse gas emissions, and build a more sustainable and resilient energy system. Hence, intensive research and advancements are needed to optimize H2 energy for broader applications in Lithuania
Deep reinforcement learning for a self-driving vehicle operating solely on visual information /
No full textThis study investigates the application of Vision Transformers (ViTs) in deep reinforcement learning (DRL) for autonomous driving systems that rely solely on visual input. While convolutional neural networks (CNNs) are widely used for visual processing, they have limitations in capturing global patterns and handling complex driving scenarios. To address these challenges, we developed a ViT-based DRL model and evaluated its performance through extensive training in the MetaDrive simulator and testing in the high-fidelity AirSim simulator. Results show that the ViT-based model significantly outperformed CNN baselines in MetaDrive, achieving nearly seven times the average distance traveled and an 87% increase in average speed. In AirSim, the model exhibited superior adaptability to realistic conditions, maintaining stability and safety in visually complex environments. These findings highlight the potential of ViTs to enhance the robustness and reliability of vision-based autonomous systems, offering a transformative approach to safe exploration in diverse driving scenarios
Circularity and decarbonization synergies in the construction sector: implications for zero-carbon energy policy /
No full textThis literature review explores the synergies between circularity and decarbonization principles in the construction sector, focusing on their potential to accelerate the transition to a carbon-neutral future. Through analysis of 61 studies, critical barriers are identified, such as data gaps, insufficient recycling infrastructure, and regulatory fragmentation, that hinder the integration of circular and low-carbon strategies. Regional disparities reveal that developed regions, supported by robust policies and infrastructure, lead in circularity adoption, while developing regions face systemic challenges, including limited material recovery networks and technological barriers. Previous studies have largely examined circularity and decarbonization separately, whereas this review provides a synthesis of their interdependencies, focusing on implementation challenges and regional disparities, highlighting synergetic solutions such as fiscal incentives, material passports and stricter end-of-life waste regulations, biobased and carbon-negative material innovations, and digitalization through tools like Building Information Modeling (BIM) and/or digital twins. However, complexity of circular solutions and lack of interdisciplinary collaboration forms a barrier against integration. This review emphasizes the need for standardized frameworks, cross-sectoral coordination, and targeted investments to ease integration of circularity and decarbonization
Savitvarkį monosluoksnį formuojančios [2-(9H-karbazol-9-il)etil]fosfonrūgšties alternatyvos ir jų taikymas optoelektronikoje.
No full textOrganic semiconductors are a major focus in the design and development of next-generation optoelectronics, such as perovskite or organic solar cells. These compounds often make a significant contribution not only to efficiency but also to the long-term stability of the devices. The introduction of self-assembled monolayer (SAM) hole-transporting semiconductors, such as [2-(9H-carbazol-9-yl)ethyl]phosphonic acid (2PACz) and [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid (MeO-2PACz), a major step forward in the development of the next-generation solar cells has been made. Such compounds are capable of forming a self-assembled monolayer on a surface of various metal oxides, thus simplifying the semiconductor deposition procedure and providing conformal surface coverage. They are also cost effective because dilute solutions are used to coat a single molecule thick layer, ensuring minimal material consumption. Currently, 2PACz and similar self-assembled monolayer compounds are being successfully used to construct perovskite, organic, tandem solar cells or organic light-emitting diodes. This thesis presents the author’s synthesized hole transporting SAM compounds where strategies of different chromophore selection and different functional group introduction have been employed. The obtained SAM materials have been used for further investigation in perovskite and bulk heterojunction organic solar cells, organic light emitting diodes and gas sensors
Novel second-order transfer section for frequency selective response generation in comb filters /
No full textThis paper introduces a novel unified second-order filtering topology for standard band-reject and inverting band-reject filtering, enabling selective response generation. It is applied in the design of special comb filters that allow attenuation as well as amplification of specific bands. The presented solution offers several advantageous features in topology, enhanced cascadability, better parameter-setting performance, and the use of readily available off-the-shelf components, all while reducing overall costs. This is a significant improvement compared to the previous solutions in this field, which relied on a very expensive CMOS process. The topology employs a combination of an operational transconductance amplifier and a current feedback amplifier. The intended center frequencies and transfer values of the comb filter are set to 50 Hz (−20 dB), 1 kHz (+26 dB), 10 kHz (+17 dB), and 100 kHz (−30 dB). The comb filter was experimentally verified via simulations as well as laboratory measurements utilizing LT1228 devices in a fabricated prototype
Lasing in an assembled array of silver nanocubes /
No full textWe demonstrate a surface lattice resonance (SLR)-based plasmonic nanolaser that leverages bulk production of colloidal nanoparticles and assembly on templates with single particle resolution. SLRs emerge from the hybridization of the plasmonic and photonic modes when nanoparticles are arranged into periodic arrays and this can provide feedback for stimulated emission. It has been shown that perfect arrays are not a strict prerequisite for producing lasing. Here, we propose using high-quality colloids instead. Silver colloidal nanocubes feature excellent plasmonic properties due to their single-crystal nature and low facet roughness. We use capillarity-assisted nanoparticle assembly to produce substrates featuring SLR and comprising single nanocubes. Combined with the laser dye pyrromethene-597, the nanocube array lases at 574 nm with <1.2 nm linewidth, <100 μJ cm-2 lasing threshold, and produces a beam with <1 mrad divergence, despite less-than-perfect arrangement. Such plasmonic nanolasers can be produced on a large-scale and integrated in point-of-care diagnostics, photonic integrated circuits, and optical communications applications