Search Results (346)

As the demand for energy-efficient homes continues to rise, the importance of advanced mechanical ventilation systems in maintaining indoor air quality (IAQ) has become increasingly evident. However, challenges related to energy balance, IAQ, and occupant thermal comfort persist. This review examines the performance of mechanical ventilation systems in regulating indoor climate, improving air quality, and minimising energy consumption. The findings indicate that demand-controlled ventilation (DCV) can enhance energy efficiency by up to 88% while maintaining CO₂ concentrations below 1000 ppm during 76% of the occupancy period. Heat recovery systems achieve efficiencies of nearly 90%, leading to a reduction in heating energy consumption by approximately 19%. Studies also show that employing mechanical rather than natural ventilation in schools lowers CO₂ levels by 20–30%. Nevertheless, occupant misuse or poorly designed systems can result in CO₂ concentrations exceeding 1600 ppm in residential environments. Hybrid ventilation systems have demonstrated improved thermal comfort, with predicted mean vote (PMV) values ranging from –0.41 to 0.37 when radiant heating is utilized. Despite ongoing technological advancements, issues such as system durability, user acceptance, and adaptability across climate zones remain. Smart, personalized ventilation strategies supported by modern control algorithms and continuous monitoring are essential for the development of resilient and health-promoting buildings. Future research should prioritize the integration of renewable energy sources and adaptive ventilation controls to further optimise system performance. Full article

The concept of the 15-minutes city [15 MC] focuses on providing important services within proximity and accessibility through active travel like walking or biking. While this model is becoming popular in urban planning and academic discourse, its implementation faces challenges in both densely populated developing and developed countries. This study aims to conduct a systematic review of recent literature to (1) identify the core components of the 15 MC model, (2) examine planning tools and strategies used in its implementation, (3) compare successes and challenges across global contexts, particularly in densely populated and resource-constrained areas, and (4) offer practical recommendations for adapting the model to meet local needs. The study reviewed 33 research papers published in the last five years [2019–2024]. Following PRISMA guidelines, a structured screening and selection process was conducted using databases such as Scopus, Web of Science, and Google Scholar. Thematic analysis revealed major challenges for implementing the 15 MC in the Global South, including urban informality, gaps in infrastructure, and complex governance issues. Moreover, the review points out the potential risks of exclusion and gentrification if the specific needs of different contexts are not considered. While high-income countries tend to focus on sustainability and making neighborhoods walkable, developing countries struggle with deeper structural problems that make equitable implementation harder. This study emphasizes the need for locally adaptive frameworks in planning 15 MCs and aims to develop inclusive urban policies that support Sustainable Development Goal 11, which seeks to make cities inclusive, safe, resilient, and sustainable. Full article

Concentrating photovoltaic-thermal (CPVT) collectors use reflective surfaces to focus sunlight onto a smaller receiver area, increasing thermal energy output while maintaining annual energy efficiency. Ray-tracing simulations are employed in this study using Tonatiuh to optimise the characteristics of the Double MaReCo (DM) collector, which is an improved version of the commercially available Solarus Power Collector (PC). Focused on enhancing electrical performance, the photovoltaic (PV) cell configurations are varied on the bottom side of the receiver, while the top-side PV cells remain constant. The study also analyses the influence of diodes and transparent gables on the annual solar irradiance received by the PV cells. From the analysis, it is observed that the specific annual irradiance received by the PV cells in the DM collector with transparent gables is nearly 64% more compared to that of the PC counterpart. It is also observed that the transparency of gables becomes significant only when the whole area of the receiver is covered by PV cells. With the goal of improving performance while lowering the cost and complexity of the DM collector, the study investigates various collector design characteristics that may shed more light on optimising the current model. Full article

Graphene interfaces in layered dielectrics can support unique electromagnetic modes, but analyzing these modes requires robust computational techniques. This work presents a numerical method for computing TE-polarized eigenmodes in a planar stratified dielectric slab with an infinitesimally thin graphene sheet at its interface. The governing boundary-value problem is reformulated as coupled initial-value problems and solved via a customized shooting method, enabling accurate calculation of complex propagation constants and field profiles despite the discontinuity at the graphene layer. We demonstrate that the graphene significantly alters the modal spectrum, introducing complex leaky and surface waves with attenuation due to graphene’s conductivity. Numerical results illustrate how the layers’ inhomogeneity and the graphene’s surface conductivity influence mode confinement and loss. These findings confirm the robustness of the proposed computational approach and provide insights relevant to the design and analysis of graphene-based waveguiding devices. Full article

This study evaluates the effectiveness of augmented reality (AR), using the Microsoft™ HoloLens™™ 2, for identifying and localizing PCB components compared to traditional PDF-based methods. Two experiments examined the influence of user expertise, viewing angles, and component sizes on accuracy and usability. The results indicate that AR improved identification accuracy and user experience for non-experts, although it was slower than traditional methods for experienced users. Optimal performance was achieved at 90° viewing angles, while accuracy declined significantly at oblique angles. Medium-sized components received the highest confidence scores, suggesting favorable visibility and recognition characteristics within this group, though further evaluation with a broader component distribution is warranted. Participant feedback highlighted the system’s intuitive interface and effective guidance, but also noted challenges with marker stability, visual discomfort, and ergonomic limitations. These findings suggest that AR can enhance training and reduce errors in electronics manufacturing, although refinements in marker rendering and user onboarding are necessary to support broader adoption. This research provides empirical evidence on the role of AR in supporting user-centered design and improving task performance in industrial electronics workflows. Full article

Knee exoskeletons are sophisticated wearable devices engineered to aid or augment human movement, especially in rehabilitation and mobility assistance contexts. To address reliability concerns, the proposed knee exoskeleton incorporates a fault-tolerant control system using a fault detection, isolation and reconfiguration (FDI) technique. This system enables the exoskeleton to continue functioning even if one of the actuators experiences a fault, ensuring user safety and continuous operation. For actuator fault detection, analytical redundancy relations (ARRs) are derived from the bond graph model of the knee exoskeleton. ARRs are monitored for actuator fault detection and isolation. In this work, there is no fault initially; after some time, a fault is created in the rotary actuator; finally, the faulty actuator is reconfigured by another rotary actuator. Simulation findings illustrate the suggested FDI system’s effectiveness in improving the robustness of knee exoskeletons during the sit-to-stand motion. The proposed system successfully reconfigures itself in response to faults. Full article

Rapid urbanization in Karachi, Pakistan, has resulted in increased impervious surfaces, leading to significant challenges, such as frequent flooding, urban heat islands, and loss of vegetation. These issues pose challenges to urban resilience, livability, and sustainability, which further demand solutions that incorporate urban greening and effective water management. This research uses remote sensing technologies and Geographic Information Systems (GISs), to analyze current surface treatments and their relationship to Karachi’s blue-green infrastructure. By following this approach, we evaluate flood risk and identify key flood-conditioning factors, including elevation, slope, rainfall distribution, drainage density, and land use/land cover changes. By utilizing the Analytical Hierarchy Process (AHP), we develop a flood risk assessment framework and a comprehensive flood risk map. Additionally, this research proposes an innovative Sponge City (SC) framework that integrates nature-based solutions (NBS) into urban planning, especially advocating for the establishment of green infrastructure, such as green roofs, rain gardens, and vegetated parks, to enhance water retention and drainage capacity. The findings highlight the urgent need for targeted policies and stakeholder engagement strategies to implement sustainable urban greening practices that address flooding and enhance the livability of Karachi. This work not only advances the theoretical understanding of Sponge Cities but also provides practical insights for policymakers, urban planners, and local communities facing similar sustainability challenges. Full article

A positive school climate is characterized by a higher degree of well-being among students, reduced bullying, and improved academic performance. While many initiatives are aimed at creating a positive school climate, discussions in both research and theory frequently fail to acknowledge the essential role of school personnel. This study examines a purposeful sample of Swedish middle-school students (4th to 9th grade) of school personnel’s noticing in fostering or hindering a positive school climate. Fifteen (15) focus groups and 19 semi-structured interviews were analyzed, covering 133 participants selected from three schools (age range 10 to 16 years) in a Swedish municipality. Drawing on a framework of professional noticing and positive school and classroom climate, the investigation was conducted using a case study approach and analyzed with the help of content analysis. The results highlighted the importance placed by students on school personnel noticing appropriate things/events and responding accordingly. For this to happen, personnel need to (a) notice and make themselves visible; (b) be actively observing as a prerequisite to their noticing; (c) be receptive to noticing; (d) notice and grasp a full picture, including students’ perspectives; and (e) connect their noticing with appropriate actions. Full article

Energy-efficient renovation of the existing building stock is essential for achieving the ambitious sustainability goals set by the European Commission for 2030. However, implementing sustainable renovation has proven challenging, as numerous studies have concluded. Multi-family buildings are a significant part of Sweden’s building stock and require renovations to meet energy efficiency standards. This study aims to provide an overview of sustainable renovation practices in Sweden’s multi-family buildings. A semi-open structured questionnaire was developed to examine the adoption of these practices, with data collected from 11 housing companies. The responses reveal that Swedish housing companies are well aware of the three key aspects of sustainability and actively consider them in their renovation projects. Notably, specific energy use and investment costs are the most commonly used methods for evaluating the environmental and economic aspects, respectively. However, there is a lack of a common method for assessing the social aspects of renovation projects. Additionally, this study highlights the need for standardized decision-making tools in multi-family building renovations. Full article

As the focus on climate action and sustainable development of the shipping industry intensifies, the maritime sector has intensified its focus on decarbonization. Although the ferry sector accounts for a small part of the global fleet, it plays a crucial role in specific regions. This study examines data from an energy monitoring system installed on a double-ended Estonian ferry over the period from 2022 to 2024. The empirical results clearly show that targeted adjustments can lead to substantial fuel consumption reductions as the optimal operation of the vessel requires equal power from the aft and fore engines particularly when operating under cold or icy conditions. Additionally, the research finds that real-time energy monitoring together with integrating environmental factors supports energy efficiency and fulfilling regulatory requirements. The analysis reveals that environmental corrections and balanced decision-making can generate fuel savings and extended emission reductions. The suggested framework offers ferry operators practical and economical ways of meeting sustainability requirements. Full article

This study explored the role of airports in the aviation sector from both energy and sustainability perspectives, highlighting their potential contribution to reducing the sector’s carbon emissions. The methodology involved a literature review and a questionnaire distributed to both airports and aviation organizations. The results from these approaches indicated varying focuses on tackling the subject. The literature review results indicated a clear preference in the papers for SAF solutions over the development of more environmentally friendly airports. Adoption of 100% SAF in aircraft is still in its early stages of development and can be considered a long-term goal because it requires heavy engineering intervention and alteration of aircraft engines. The transition of airports’ infrastructures, on the other hand, can be visualized as a feasible and attainable goal and hence should be considered a short-term goal to attain. Many airports, including respondents to the questionnaire, have already worked on their infrastructure; however, they also expressed concerns about the lack of enabling policies and incentives. Other action steps, such as close collaborations among stakeholders, enhancing research and development, and government support, were also seen as significant for establishing greener airports. The literature results indicate a major research gap in a significant integral part of the aviation sector (i.e., greener airports). It is therefore important that member states collaborate and work closely with key organizations such as ICAO, IATA, and the UN through the latter’s Sustainable Development Goals (SDGs) to breach this research gap and establish more sustainable airports in the near future. Full article

The individual, as found primarily in modern Western civilization, is defined as “the independent, autonomous and thus (essentially) nonsocial moral being”, “the rational being” who is “the normative subject of institutions”. This is the definition of the individual we adhere to in this text. This text delves into the intricate dimensions of the concept of the individual by exploring the theological foundations inherent in Western thought. Rooted in Max Weber’s assertion regarding the theological meanings of Man’s self-perception, the entry emphasizes the pivotal role of theological understandings in shaping the concept of the individual. Focusing on the influence of Christian perspectives on the development of the concept of the individual, the article traces the historical entwining of theology and the concept of Man between antiquity and medieval times. Full article

Reinforced concrete (RC) walls are mainly used in RC structures to resist gravity and lateral forces. These structural elements may need to be upgraded to withstand additional forces and extend their life cycle. Therefore, it is crucial to provide effective strengthening techniques using low-cost sustainable materials under optimal conditions to rehabilitate RC walls. This study presents an experimental and numerical investigation of reinforced normal concrete (NC) walls strengthened with near-surface mounted (NSM) steel bars, confined with or without an externally bonded reinforced (EBR) galvanized steel sheets (GSSs). A total of six RC walls were constructed, loaded, and tested to failure. The examined parameters included the type of strengthening technique, materials used, and the position and configuration of the strengthening. Both EBR and NSM techniques were applied using GSSs and steel bars, respectively. The configurations were introduced in vertical and horizontal positions to resist gravity and lateral forces, respectively. The experiments revealed that these parameters significantly influenced the crack control, energy absorption, mode of collapse, and ultimate load capacity. Nonlinear three-dimensional finite element models were developed and verified against experimental results, achieving a validation accuracy of 95% on average. This was followed by a parametric study investigating the effect of confinement with or without vertical reinforcements. Both experimental and numerical results confirmed that the strengthening could increase the ultimate load capacity from 20% to 38%. Full article

This article discusses the future role of agnosticism and its possible meaning in a post-secular, Western cultural sphere, with a special focus on the situation in Sweden. A characteristic of this context, which gives agnosticism a different role than before, is a diminishing interest in traditional ontological questions such as the existence of God. This assumption is illustrated by a comparative analysis of four examples of how atheism and secular views of life are shaped today, all of which in one way or another cross the line between religious and secular but also give philosophical questions about what exists or not a diminished role. It is argued in this article that a revised concept of agnosticism, detached from ontological thinking, together with such concepts as semi-secularity, post-atheism and post-secularity, can offer conceptual instruments for a better understanding of the main tendencies in our time. Full article

To understand how telework is perceived among occupational groups with different work tasks within the same company, this qualitative study aimed to explore how managers and employees experience telework in relation to well-being, individual performance, and the work environment. This qualitative study used a phenomenographic approach. Fourteen online interviews, comprising seven managers and seven employees from the same industrial company, were conducted between February 2022 and September 2023. The data were analyzed inductively to capture variations in telework perceptions. The findings showed that telework is not universally beneficial or challenging; its effectiveness depends on contextual factors such as team setting, job role, type of work, and organizational culture. Telework benefits both employees and managers engaged in individual tasks (e.g., reading, drafting contracts, and preparing reports) or global collaborations, including improved well-being, work–life balance, and overall performance. However, starting with an office-based period that facilitated team cohesion, faster learning, and a deeper understanding of the organizational culture. Face-to-face onsite work could be time-consuming and, therefore, stressful for some, but it is time-saving for others. Onsite employees and managers faced increased workloads when colleagues teleworked, as employees tended to rely more on colleagues physically present in the office. This research highlights the need for tailored strategies to enhance the advantages of telework while reducing its challenges. It contributes to existing research by providing nuanced insights into the relationship between telework and occupational groups within an industrial setting and offering practical guidance for telework in this field. Full article