Search Results (14,287)

Energy efficiency (EE) remains an underexploited opportunity in many developing economies, where a complex interplay of policy, institutional, and market-related challenges limit its implementation at scale. This study explores the structural, economic, and policy-related constraints affecting the EE market in Jordan, a country with a high dependence on imported energy. Using a multi-framework approach, we apply the political, economic, social, technological, environmental, and legal (PESTEL) framework to categorize these barriers, complemented by Brown’s business model (BM) typology to enhance the analytical depth. Primary data were collected through semi-structured interviews with key market actors. The findings highlight issues such as economic volatility, regulatory fragmentation, and the structural biases associated with donor-driven interventions, which contribute to an uneven and loosely regulated market environment in which businesses face significant scaling challenges. This study reflects on international experience to explore how strategies from other contexts might inform markets’ adaptation in emerging economies. This study concludes with targeted policy recommendations aimed at clarifying regulatory pathways and supporting more effective market delivery. This research contributes to ongoing policy discourse by highlighting how context-specific BM innovations might help address systemic barriers, while potentially supporting national energy goals. Full article

This paper argues for a paradigm shift in heritage conservation—one that integrates affective connections, digital technologies, and circular economy principles to respond to the complex realities of urban transformation. Using the case of the Dennys Lascelles Wool Store in Geelong, this position paper contends that current preservation models, rooted in the Authoritative Heritage Discourse (AHD), are inadequate for addressing the nuanced value of industrial heritage, particularly when physical structures are altered or lost. The demolition of the Wool Store’s iconic bow truss structure exemplifies the tension between rapid urban development and heritage conservation. While the physical element has been removed, the site’s cultural and emotional resonance persists, underscoring the role of affect in shaping collective memory and place identity. This paper positions affect as a critical component of heritage discourse—one that expands beyond materiality to include sensory and emotional dimensions often overlooked by institutional frameworks. Digital heritage technologies offer powerful tools to document, represent, and interpret both tangible and intangible aspects of cultural heritage. In the case of the Wool Store, these tools not only preserve what has been lost but also invite public engagement and reinterpretation. However, preservation should not end with digital replication. A circular economy approach calls for the adaptive reuse of remaining structures, allowing historic sites to evolve functionally while retaining their significance. Full article

Agricultural waste poses significant environmental, economic, and social challenges globally, with estimates indicating that 10–50% of agricultural products are discarded annually as waste. This review explores strategies for managing agricultural waste to mitigate its adverse impacts and promote sustainable development. Agricultural residues, such as those from sugarcane, rice, and wheat, contribute to pollution when improperly disposed of through burning or burying, contaminating soil, water, and air. However, these residues also represent untapped resources for bioenergy production, composting, mulching, and the creation of value-added products like biochar, bioplastics, single-cell protein and biobased building blocks. The paper highlights various solutions, including integrating agricultural waste into livestock feed formulations to reduce competition for human food crops, producing biofuels like ethanol and biodiesel from lignocellulosic materials, and adopting circular economy practices to upcycle waste into high-value products. Technologies such as anaerobic digestion for biogas production and gasification for synthesis gas offer renewable energy alternatives and ample feedstocks for gas fermentation while addressing waste management issues. Composting and vermicomposting enhance soil fertility, while mulching improves moisture retention and reduces erosion. Moreover, the review emphasizes the importance of policy frameworks, public-private partnerships, and farmer education in promoting effective waste management practices. By implementing these strategies, agricultural waste can be transformed into a resource, contributing to food security, environmental conservation, and economic growth. Full article

Hydrogen compression is a critical process in hydrogen storage and distribution, particularly for energy infrastructure and transportation. As hydrogen technologies expand beyond limited industrial applications, they are increasingly supporting the green economy, including offshore energy systems, smart ports, and sustainable marine industries. Efficient compression technologies are essential for ensuring reliable hydrogen storage and distribution across these sectors. This study focuses on optimizing hydrogen compression using a Liquid Piston Hydrogen Compressor through numerical simulations and scaling analysis. The research examines the influence of compression chamber geometry, including variations in radius and height, on thermal behavior and energy efficiency. A computational model was developed using COMSOL Multiphysics^® 6.0, incorporating Computational Fluid Dynamics (CFD) and heat transfer modules to analyze thermodynamic processes. The results highlight temperature distribution in hydrogen, working fluid, and chamber walls at different initial pressures (3.0 MPa and 20.0 MPa) and compression stroke durations. Larger chamber volumes lead to higher temperature increases but reach thermal stabilization. Increasing the chamber volume allows for a significant increase in the performance of the hydraulic compression system with a moderate increase in the temperature of hydrogen. These findings provide insights into optimizing hydrogen compression for enhanced production and broader applications. Full article

As sustainability gains prominence, the circular economy has encouraged the valorization of agri-food by-products, which are rich in phenolic compounds known for their antioxidant and anti-inflammatory properties. Conventional extraction methods commonly employ organic solvents, which contradict green chemistry principles. Natural deep eutectic solvents (NaDESs) have emerged as environmentally friendly alternatives for recovering bioactive compounds from food waste. This review investigated recent studies (2020–2024) on ultrasound (UAE), microwave (MAE), and pressurized liquid extraction (PLE) using NaDESs to extract phenolic compounds from agri-food by-products. A total of 116 publications were initially identified, of which 19 met the inclusion criteria. UAE combined with NaDESs proved effective, particularly for fruit and oilseed residues. MAE achieved good yields for phenolic acids and flavonoids but showed limitations on high temperatures. PLE, though less explored, demonstrated promising results when optimized for temperature, pressure, and NaDES composition. The combination of NaDESs with assisted extraction techniques enhanced yield, selectivity, and environmental performance compared to conventional approaches. These findings highlight a greener and more efficient strategy for phenolic recovery within a biorefinery framework. Ultimately, this approach contributes to the sustainable management and valorization of agri-food by-products, supporting circular economy principles and the development of cleaner extraction technologies for functional ingredients. Full article

The growing need for sustainable and flexible automation solutions has led to the exploration of transforming traditional industrial robots into collaborative robots (cobots). This paper presents a framework for the conversion of conventional industrial robots into safe, intelligent, and sustainable cobots, leveraging advancements in artificial intelligence and computer vision and the principles of the circular economy. The proposed modular framework contains key components such as visual perception, cognitive adaptability, safe human–robot interactions, and reinforcement learning-based decision-making. Our methodology includes a comprehensive analysis of safety standards (e.g., ISO/TS 15066), robot typologies suitable for retrofitting, and sustainability strategies, including remanufacturing and lifecycle extension. A multi-phase implementation approach is laid out for a theoretical design to contribute to the development of cost-effective and environmentally responsible robotic systems, offering a scalable solution for extending the usability and social acceptance of legacy robotic platforms in collaborative settings. Full article

Transportation infrastructure systems sit at the nexus of urban economic development and emission mitigation. The primary objective is to identify and quantify the key factors influencing CI, with a focus on both the conventional and emerging indicators through an innovative MLP neural network developed using the data of 20 Chinese transportation enterprises that have a business focus on the construction and operation sector from 2018 to 2022. The hypothesis is that integrating unconventional indicators—such as business model entropy and green revenue share—alongside traditional metrics can significantly enhance the predictive accuracy for CI. The results show that business model entropy explains 42.6% of carbon intensity (Cl) variability through green revenue diversification pathways, while emissions trading system (ETS) exposure accounts for 51.83% of decarbonization outcomes via price-signaling effects. The analysis reveals that a critical operational threshold–renewable energy capacity below 75% fails to significantly reduce Cl, and capex/revenue ratios exceeding 73.58% indicate carbon lock-in risks. These findings enable policymakers to prioritize industries with sub-75% renewable adoption while targeting capex-intensive sectors for circular economy interventions. The novelty of this work lies in the application of advanced machine-learning techniques to a comprehensive, multi-source dataset, enabling a nuanced analysis of CI drivers and offering actionable insights for policymakers and industry stakeholders aiming to decarbonize transport infrastructure. Full article

This study explores the emerging link between digital marketing and the circular economy, situated within the broader context of sustainability and digital transformation. Through a scientometric analysis of 276 documents indexed in Scopus, the research maps the conceptual, intellectual, and collaborative landscape of this intersection. The dataset was refined using the PRISMA standards, and the analysis was carried out with the R package bibliometrix. The findings reveal a highly fragmented body of literature, with a few prolific authors and limited international cooperation. Most of the influential publications are concentrated in a small number of sources, particularly the journal Sustainability. Thematic mapping identifies growing interest in areas such as consumer perception, sustainable development, and the adoption of digital tools by micro-enterprises, while other topics like recycling or public health remain peripheral. Although the scholarly output has surged in recent years (especially during 2023 and 2024), the field still lacks coherent theoretical frameworks or dominant research schools. Overall, digital marketing appears to be a promising driver for promoting circular practices, but further applied studies and enhanced international collaboration are essential to consolidate this line of inquiry. Full article

Urban green development has become a crucial approach for balancing ecological conservation and socio-economic development. The digital economy (DE) and new-type urbanization (NTU), as technological and social systems, respectively, are both driving urban green development. In this context, furthering their synergistic effects could substantially improve urban sustainability outcomes. Grounded in sociotechnical systems theory, this study applied pooled and multi-period fuzzy-set qualitative comparative analysis (fsQCA) to analyze urban green development pathways in 79 Yellow River Basin cities (2020–2022). The pooled fsQCA indicates that urban green development is driven by synergistic interaction within the NTU-DE subsystem, especially industrial digitalization–spatial urbanization. The multi-period fsQCA further demonstrates that industrial digitization has always existed as a core condition, which means that it plays a more general role. In addition, the Yellow River Basin exhibits distinct regional variations in urban green development, where the downstream region is dominantly driven by DE and spatial urbanization, the upstream region by industrial digitization, and the midstream region demonstrates diversified pathways. This study enhances understanding of complex system interactions in urban green development and provides policy-relevant insights. For policy implementation, local governments should not only prioritize effective synergies between industrial digitization and spatial urbanization but also develop differentiated strategies for the DE and NTU subsystems based on local conditions. Full article

Foot-and-mouth disease virus (FMDV) continues to pose a significant threat to livestock health and the global agricultural economy, particularly in endemic regions of Asia, Africa, and the Middle East. Current vaccines based on chemically inactivated FMDV present several challenges, including biosafety risks, high production costs, and limited effectiveness against emerging viral variants. To overcome these limitations, we developed virus-like particle (VLP) vaccines targeting FMDV serotypes O, A, and Asia1 using a recombinant Escherichia coli expression system. The resulting VLPs self-assembled into 25–30 nm particles with native-like morphology and antigenic properties, as confirmed by transmission electron microscopy, SDS-PAGE, and Western blot analysis. Immunogenicity was evaluated in mice and pigs using ELISA and virus neutralization tests (VNT), and protective efficacy was assessed through viral challenge studies. All VLPs induced strong serotype-specific antibody responses, with ELISA PI values exceeding 50% and significantly increased VNT titers after booster immunization. In mice, PD₅₀ values were 73.5 (A-type), 32.0 (O-type), and 55.7 (Asia1-type); in pigs, PD₅₀ values reached 10.6 (O-type) and 22.6 (Asia1-type). Notably, the vaccines induced robust immune responses even at lower antigen doses, suggesting the feasibility of dose-sparing formulations. These findings demonstrate that FMDV VLPs produced in E. coli are highly immunogenic and capable of eliciting protective immunity, highlighting their promise as safe, scalable, and cost-effective alternatives to conventional inactivated FMD vaccines. Full article

This study aims to examine the latest literature at the intersection of prefabrication, modularity, and the circular economy (CE) through a bibliometric analysis. This systematic review follows five key steps: design and conceptualization, bibliometric data collection via the Scopus database, assessment of the collected data, data visualization, and discussion of the findings. The results are categorized into five main themes: prefabrication and modularity, CE in the construction sector, energy and environmental life cycle assessments, life cycle costing (LCC), and digitalization. The findings reveal that prefabricated and modular systems align with CE principles, supported by strategies such as disassembly and deconstruction design, as well as recycling and reuse. However, the direct connection between prefabrication/modularity and CE remains relatively weak, with environmental life cycle assessment (LCA) and building information modelling (BIM) emerging as the two primary methodologies bridging these concepts. To further advance the integration of prefabrication and modularity in CE, there is a need for the development of reliable guidelines and regulations that establish these practices as core requirements within the construction industry. Full article

Many of the existing theoretical and empirical studies ignore the two-way relationship between a sovereign’s credit risk and economy. To address this gap, we develop a theoretical model that incorporates the feedback effects of sovereign-debt credit risk on a country’s economy and then provide empirical implications. The model links the risks of sovereign debt and economic fundamentals through a two-way transmission mechanism. In doing so, it demonstrates how economic-fundamentals-driven sovereign-debt credit risk can have a significant impact on economic fundamentals through a feedback effect that has the potential to significantly raise the sensitivity of a country’s economic performance to shocks from both the credit risk associated with sovereign debt and economic fundamentals. The outcomes of the theoretical model are then verified by empirically testing the feedback effects using a structural equation model (SEM) framework on data covering sovereign debt defaults worldwide. We demonstrate how disregarding feedback effects may result in information that is insufficient and less helpful to public-debt-management policymakers. Full article

The broadening adoption of interconnected systems within smart city environments is fundamental for the progression of digitally driven economies, enabling the refinement of city administration, the enhancement of public service delivery, and the fostering of ecologically sustainable progress, thereby aligning with global sustainability benchmarks. However, the pervasive distribution of Internet of things (IoT) apparatuses introduces substantial security risks, attributable to the confidential nature of processed data and the heightened susceptibility to cybernetic intrusions targeting essential infrastructure. Commonly, these devices exhibit deficiencies stemming from restricted computational capabilities and the absence of uniform security standards. The resolution of these security challenges is paramount for the full realization of the advantages afforded by IoT without compromising system integrity. Cryptographic protocols represent the most viable solutions for the mitigation of these security vulnerabilities. However, the limitations inherent in IoT edge nodes complicate the deployment of robust cryptographic algorithms, which are fundamentally reliant on finite-field multiplication operations. Consequently, the streamlined execution of this operation is pivotal, as it will facilitate the effective deployment of encryption algorithms on these resource-limited devices. Therefore, the presented research concentrates on the formulation of a spatially and energetically efficient hardware implementation for the finite-field multiplication operation. The proposed arithmetic unit demonstrates significant improvements in hardware efficiency and energy consumption compared to state-of-the-art designs, while its systolic architecture provides inherent timing-attack resistance through deterministic operation. The regular structure not only enables these performance advantages but also facilitates future integration of error-detection and masking techniques for comprehensive side-channel protection. This combination of efficiency and security makes the multiplier particularly suitable for integration within encryption processors in resource-constrained IoT edge nodes, where it can enable secure data communication in smart city applications without compromising operational effectiveness or urban development goals. Full article

Sustainable development goals aim to build a sustainable and prosperous world for future generations. Education, one of the sustainable development goals, is also an important predictor of other development goals. The aim of this study is to analyze the views and suggestions of students and teachers on sustainable development goals. In this context, semi-structured interviews were conducted with 30 students and three teachers who participated in the study and the interview form prepared by the researchers as a data collection tool was analyzed with content analysis. As a result of the analysis, students’ answers were concentrated on the themes of environmental pollution, social equality, renewable energy sources, natural habitats, and improvement of the economy regarding sustainable development goals; teachers’ answers were concentrated on the themes of changes in curriculum and textbooks, in-school/outside-school activities, and collaborations that schools will establish with institutions. As a result of this study, it was concluded that students’ views and teachers’ solution suggestions regarding sustainable development goals were limited. Since this study is a qualitative study covering both students and teachers, it is expected to provide a good starting point in planning and developing educational strategies for sustainable development goals. Full article

This article examines urban mining in Brazil, highlighting its unique context compared to other regions. While European Union focuses on critical metal supply and advanced Waste Electrical and Electronic Equipment (WEEE) legislation and circular economy, Brazil’s urban mining is primarily driven by waste management and social inclusion. The current investigation was underpinned by the PRISMA extension for Scoping Reviews (PRISMA-ScR framework), using targeted searches on the Web of Science platform for technological processes and the Brazilian scenario, complemented by an analysis of legislative evolution and a Critical Discourse Analysis of national policies. The results indicate that, despite advanced legislation, significant gaps exist between discourse and practice, highlighting the need for technological appropriation, specific public policies that incentivize reverse logistics and the integration of the informal sector, and overcoming infrastructural challenges. It concludes that Brazil has a unique opportunity to develop an urban mining model that pioneeringly integrates environmental sustainability, technological innovation, and social inclusion, demanding coordinated efforts to overcome existing barriers. Full article