Search Results (1,312)

This scoping review paper provides an overview of the evolution, the current stage, and the future prospects of fracture studies on composite laminates. A fundamental understanding of composite materials is presented by highlighting the roles of the fiber and matrix, outlining the applications of various synthetic fibers used in current structural sectors. Challenges posed by interlaminar delamination, one of the critical failure modes, are highlighted. This paper systematically discusses the fracture behavior of these laminates under mixed-mode and complex loading conditions. Standardized fracture toughness testing methods, including Mode I Double Cantilever Beam (DCB), Mode II End-Notched Flexure (ENF) and Mixed-Mode Bending (MMB), are initially discussed, which is followed by a decade-wide chronological analysis of fracture mechanics approaches. Key advancements, including toughening mechanisms, Cohesive Zone Modeling (CZM), Virtual Crack Closure Technique (VCCT), Extended Finite Element Method (XFEM) and Digital Image Correlation (DIC), are analyzed. The review also addresses recent trends in fracture studies, such as bio-inspired architecture, self-healing systems, and artificial intelligence in fracture predictions. By mapping the trajectory of past innovations and identifying unresolved challenges, such as scale integration, dataset standardization for AI, and manufacturability of advanced architectures, this review proposes a strategic research roadmap. The major goal is to enable unified multi-scale modeling frameworks that merge physical insights with data learning, paving the way for next-generation composite laminates optimized for resilience, adaptability, and environmental responsibility. Full article

This review explores the current status of green hydrogen integration into energy and industrial ecosystems. By considering notable examples of existing and developing green hydrogen initiatives, combined with insights from the relevant scientific literature, this paper illustrates the practical implementation of those systems according to their main end use: power and heat generation, mobility, industry, or their combination. Main patterns are highlighted in terms of sectoral applications, geographical distribution, development scales, storage solutions, electrolyzer technology, grid interaction, and financial viability. Open challenges are also addressed, including the high production costs, an underdeveloped transport and distribution infrastructure, the geopolitical aspects and the weak business models, with the industrial sector appearing as the most favorable environment where such challenges may first be overcome in the medium term. Full article

Hydrological drought in Central Europe is becoming an increasingly serious threat to agriculture, industry, and people due to climate change and the rising frequency and intensity of extreme weather events. The main aim of the paper was to assess the spatial variability of streamflow drought in Poland. The spatial analysis was conducted using daily streamflow series from 340 gauging stations for the period 1973–2022. Hydrological drought was defined as a period with a streamflow lower than Q_90%. The results show that, on average, hydrological droughts occur 52 times per year at a given gauging station. Drought duration and volume depend on the gauge elevation. At higher-altitude stations, shorter and smaller-volume droughts are most commonly observed. The longest droughts are recorded in Northern Poland, particularly in the Lakeland regions, which is a serious problem mainly for the agriculture sector. Hydrological droughts in Poland most frequently begin in summer and end in late summer or early autumn. Analyses showed that hydrological drought has a strong spatial distribution, and it is possible to identify five main regions with homogeneous drought duration and volume. Trend analysis of the annual number of low-flow days indicates no statistically significant trend at 46% of stations, while 54% exhibit statistically significant increases, with marked regional variability. The highest number of stations with statistically significant decreasing trends occurs in the Southern and Eastern Baltic Lake District and in the Central Poland Lowlands and Highlands with Polesie. The study highlights the necessity of enhancing water retention, particularly in the central, lowland regions of Poland. Full article

Sustainable production and material recycling as well as minimising energy input are the most important challenges of modern production engineering. Despite the accelerating development of incremental shaping technologies, machining is still an indispensable component of many machine part manufacturing processes. Like other manufacturing techniques, machining also has a significant impact on the environment, which should be reduced. One factor that has a negative impact on energy resources and the environment is the use of cutting fluids during machining. In this study, it was investigated whether it is possible to completely eliminate coolant in high-performance machining of parts made of aluminium and to what extent this limitation would affect changes in the shaped geometrical texture of the surface. To this end, experimental studies were carried out under industrial conditions, the results of which should be used in industrial production. The recommendations developed can influence the economic efficiency of mass production carried out in the automotive, engineering or aerospace sectors. The effect of the coolant on changes in the height indices and the unevenness of the surface geometrical texture as well as on changes in the indices describing its function was investigated. It was demonstrated that it is possible to perform high-performance dry machining without deteriorating surface geometrical texture. The effectiveness of dry milling is limited by the degree of surface unevenness when very high cutting speeds are used. Full article

The significant expansion of the construction sector and corresponding depletion of natural sand resources have intensified the search for sustainable alternatives, with waste foundry sand (WFS) emerging as a promising candidate. This systematic review evaluates the environmental performance and engineering feasibility of using WFS as a substitute for natural sand in construction. A PRISMA-guided search identified 152 peer-reviewed studies published between 2001 and 2024, which were categorized into four thematic areas: material characterization, construction applications, environmental impacts, and regulatory frameworks. The findings indicate that substituting 10–30% of natural sand with WFS in concrete and asphalt can deliver compressive strength within ±5% of control mixes and reduce water absorption by 5–15% at optimal replacement levels. However, contamination risks remain a concern, as chromium and copper concentrations in raw WFS have been reported at up to 931 mg/kg and 3318 mg/kg, respectively. To address these risks and ensure responsible reuse, a six-stage framework is proposed in this study, comprising end-of-waste classification, contaminant assessment, material preprocessing, certification, and regulatory monitoring. A comprehensive decision tree is also presented to guide the feasibility assessment of WFS reuse based on contaminant levels and material performance. Full article

Recently, environmental issues have compelled people worldwide to pursue sustainability and adopt circular economy practices across all engineering sectors, including polymer engineering and composite fabrication. A transition towards fabric-reinforced thermoplastics (FRTPs), a greener solution, has been recommended in recent years. On the other hand, utilizing recovered reinforcing phases, such as recycled carbon fiber (rCF), has attracted tremendous attention. In this framework, the aim of this research is to investigate the performance of acrylic-based FRTPs (Elium^® resin developed by Arkema). Woven virgin carbon fiber (vCF) and non-woven recycled carbon fiber (rCF) fabrics were used as reinforcement architectures for the fabrication of composites via resin infusion. The optimized formulation selected for the matrix showed flexural modulus and flexural strength of 5 GPa and 78 MPa, respectively. Composites prepared with woven vCF reached 36 GPa and 620 MPa values of flexural modulus and strength, respectively. The study of non-woven fabric is of particular interest, because the web is composed of recycled carbon fibers obtained from end-of-life (EoL) thermoset composite components. The results were promising; the flexural modulus reached 8 GPa, and the flexural strength was 113 MPa. Improvements are anticipated, especially in the parameters and conditions of the molding process. Full article

This study investigates how Environmental, Social, and Governance (ESG) principles can be effectively integrated into the Balanced Scorecard (BSc) framework within local government organizations (LGOs) to enhance strategic planning and sustainability performance. Addressing a gap in the literature on ESG–BSc integration in the public sector, particularly in the Greek context, the study employs a dual-method approach. First, a bibliometric analysis of 3053 academic publications (1993–2025) was conducted using Scopus data to assess the evolution and thematic focus of ESG and BSc research. Second, a structured questionnaire—comprising both closed- and open-ended questions—was administered to 17 administrative staff members of a Greek LGO in 2024. This expert sample provided insights into strategic planning practices, ESG awareness, and performance management barriers. The findings reveal low levels of ESG–BSc application, a limited strategic capacity, and institutional resistance. In response, the study proposes a novel, context-sensitive ESG-integrated BSc model tailored for small municipalities, emphasizing stakeholder participation, operational simplicity, and the alignment with national sustainability policies. The model serves as a practical tool to support public sector performance measurement, bridging the gap between sustainability goals and local governance strategy. Full article

The center–periphery paradigm has impacted on multiple disciplines in the social sciences and humanities. While criticized and revised for its duality, this paradigm has been most instrumental in tracing shifts in the dynamic positioning of world ‘players’, be they states, societies, or sectors thereof. This article follows it in highlighting the historical development of Chile, a society whose inception, in one of the most remote regions of the world, seemed to determine its path toward remaining a place at the ‘end of the world’. Still, by the late twentieth century, Chile attracted global attention, concern, and debate. Understanding this shift from the world’s periphery to the core of Cold War confrontation and of the neoliberal macroeconomic turn followed by the third wave of democratization enables us to trace how the global system evolved in the course of the late 20th and early 21st centuries, and how that Latin American country has been paradigmatic of those momentous changes. Full article

This paper presents a lightweight and cost-effective computer vision solution for automated industrial inspection using You Only Look Once (YOLO) v8 models deployed on embedded systems. The YOLOv8 Nano model, trained for 200 epochs, achieved a precision of 0.932, an mAP@0.5 of 0.938, and an F1-score of 0.914, with an average inference time of ~470 ms on a Raspberry Pi 500, confirming its feasibility for real-time edge applications. The proposed system aims to replace physical jigs used for the dimensional verification of extruded polyamide tubes in the automotive sector. The YOLOv8 Nano and YOLOv8 Small models were trained on a Graphics Processing Unit (GPU) workstation and subsequently tested on a Central Processing Unit (CPU)-only Raspberry Pi 500 to evaluate their performance in constrained environments. The experimental results show that the Small model achieved higher accuracy (a precision of 0.951 and an mAP@0.5 of 0.941) but required a significantly longer inference time (~1315 ms), while the Nano model achieved faster execution (~470 ms) with stable metrics (precision of 0.932 and mAP@0.5 of 0.938), therefore making it more suitable for real-time applications. The system was validated using authentic images in an industrial setting, confirming its feasibility for edge artificial intelligence (AI) scenarios. These findings reinforce the feasibility of embedded AI in smart manufacturing, demonstrating that compact models can deliver reliable performance without requiring high-end computing infrastructure. Full article

The primary aim of this paper is to survey the literature’s coverage of integrating circular economy practices with renewable energy sources in the manufacturing sector. A systematic review of 107 peer-reviewed articles published between 2018 and 2023 in journals within the Web of Science and Scopus databases was conducted. The review documented CE and RE applications in emerging economies across Africa, Asia, and South America, assessing the overall characteristics of the research, its methodological rigour, and the barriers to or facilitators of CE and RE integration. Integration refers to the implementation of at least one CE practice, as well as one or more RE sources, in a single context, like manufacturing. A total of 14 practices were included in this analysis because they were mentioned at least 10 times by varying authors. The practice list includes recycling (mentioned in 74 articles), reducing materials (57), remanufacturing (53), the reuse of materials (51), waste minimisation (48), renewable energy use (43), consumer awareness (38), repurposing (35), refuse (33), education and training (28), environmentally friendly design (22), environmental criteria for supplier selection (17), reverse logistics (16), and stakeholder collaboration (14). Recycling, life cycle assessment, and end-of-life management were the most common CE practices in the literature. Additionally, solar power and bioenergy emerged as the most frequently recurring areas of integration for CE practices within the RE realms. Governmental support, incentives, research and development, and strong environmental legislation were found to be the most frequently recurring facilitators of effective CE and RE integration. Organisational resistance, bureaucratic red tape, lack of human capital, limited stakeholder involvement, and insufficient collaboration were found to be important barriers to effective integration between CE and RE. Full article

The livestock sector significantly contributes to atmospheric emissions of various pollutants, such as ammonia (NH₃) and particulate matter of diameter under 2.5 µm (PM2.5) from activity and barn management. The objective of this study was to evaluate the reliability of low-cost sensors integrated with an IoT system for monitoring PM2.5 concentrations in a dairy barn. To this end, data acquired by a PM2.5 measurement device has been validated by using a high-precision one. Results demonstrated that the performances of low-cost sensors were highly correlated with temperature and humidity parameters recorded in its own IoT platform. Therefore, a parameter-based adjustment methodology is proposed. As a result of the statistical assessments conducted on this data, it has been demonstrated that the analysed sensor, when corrected using the proposed correction model, is an effective device for the purpose of monitoring the mean daily levels of PM2.5 within the barn. Although the model was developed and validated by using data collected from a dairy barn, the proposed methodology can be applied to these sensors in similar environments. Implementing reliable and affordable monitoring systems for key pollutants is crucial to enable effective mitigation strategies. Due to their low cost, ease of transport, and straightforward installation, these sensors can be used in multiple locations within a barn or moved between different barns for flexible and widespread air quality monitoring applications in livestock barns. Full article

The construction sector is responsible for over 40% of waste generated in Australia. Construction materials are responsible for around 11% of global carbon dioxide emissions, and a third of these materials can end up wasted on a construction site. Attention in research and industry has been directed towards waste management and recycling, resulting in 78% of construction and demolition waste being diverted from landfill. However, the waste hierarchy emphasises avoiding the generation of waste in the first place. In this paper, the PRISMA approach is used to conduct a systematic review with the objective of identifying waste reduction strategies employed across all stages of projects in the Australian construction industry. Scopus and Web of Science databases were used. The search returned 523 publications which were screened and reviewed; this resulted in 24 relevant publications from 1998 to 2025. Qualitative analysis identifies strategies categorised into five groupings: pre-demolition, design, culture, materials and procurement, and on-site activities. The review finds a distinct focus on strategies within the materials and procurement category. The reviewed literature includes fewer strategies for the avoidance of waste than for any of the other levels of the waste hierarchy, evidencing the need for further focus in this area. Full article

High-strength steel has high strength and low thermal conductivity, and its thin-walled parts are very susceptible to residual stress and deformation caused by cutting heat during the drilling process, which affects the machining accuracy and quality. High-strength steel thin-walled components are widely used in aerospace and other high-end sectors; however, systematic investigations into their temperature fields during drilling remain scarce, particularly regarding the evolution characteristics of the temperature field in thin-wall drilling and the quantitative relationship between drilling parameters and these temperature variations. This paper takes the thin-walled parts of AF1410 high-strength steel as the research object, designs a special fixture, and applies infrared thermography to measure the bottom surface temperature in the thin-walled drilling process in real time; this is carried out in order to study the characteristics of the temperature field during the thin-walled drilling process of high-strength steel, as well as the influence of the drilling dosage on the temperature field of the bottom surface. The experimental findings are as follows: in the process of thin-wall drilling of high-strength steel, the temperature field of the bottom surface of the workpiece shows an obvious temperature gradient distribution; before the formation of the drill cap, the highest temperature of the bottom surface of the workpiece is distributed in the central circular area corresponding to the extrusion of the transverse edge during the drilling process, and the highest temperature of the bottom surface can be approximated as the temperature of the extrusion friction zone between the top edge of the drill and the workpiece when the top edge of the drill bit drills to a position close to the bottom surface of the workpiece and increases with the increase in the drilling speed and the feed volume; during the process of drilling, the highest temperature of the bottom surface of the workpiece is approximated as the temperature of the top edge of the drill bit and the workpiece. The maximum temperature of the bottom surface of the workpiece in the drilling process increases nearly linearly with the drilling of the drill, and the slope of the maximum temperature increases nearly linearly with the increase in the drilling speed and feed, in which the influence of the feed on the slope of the maximum temperature increases is larger than that of the drilling speed. Full article

This study examines a convergence event at the trailing end of a cold front observed in the United States’ Southern Great Plains region on 28 September 1997, using an array of in situ and remote sensing instruments. The event exhibited a structure with elevated divergence near 3 km AGL and moisture transport over both warm and cold sectors. Data from Raman lidar (RL), Atmospheric Emitted Radiance Interferometer (AERI), and Radar Wind Profilers (RWP) were used to characterize vertical profiles of the event, revealing the presence of a narrow moist updraft, horizontal moisture advection, and cloud development ahead of the front. Convection parameters, Convective Available Potential Energy (CAPE) and Convective Inhibition (CIN), were derived from collocated AERI and RL. Regions of high CAPE were aligned with areas of high moisture, indicating that convection was more favorable at moist elevated levels than near the surface. RWP observations revealed vorticity structures consistent with existing theories. This study highlights the value of high-resolution, continuous profiling from remote sensors to resolve mesoscale processes and evaluate convection potential. The event underscores the role of elevated moisture and wind shear in modulating convection initiation along a trailing-end cold front boundary where mesoscale and synoptic forces interact. Full article

The maritime sector is undergoing rapid transformation, driven by increasingly stringent international regulations targeting air pollution. While newly built vessels integrate advanced technologies for compliance, the global fleet averages 21.8 years of age and must meet emission requirements through retrofitting or operational changes. This study evaluates, at environmental and economic levels, two key sulphur abatement strategies for a 1998-built cruise vessel nearing the end of its service life: (i) the installation of open-loop scrubbers with fuel enhancement devices, and (ii) a switch to marine diesel oil as main fuel. The analysis was based on real operational data from a cruise vessel. For the environmental assessment, a Tier III hybrid emissions model was used. The results show that scrubbers reduce SO_x emissions by approximately 97% but increase fuel consumption by 3.6%, raising both CO₂ and NO_x emissions, while particulate matter decreases by only 6.7%. In contrast, switching to MDO achieves over 99% SO_x reduction, an 89% drop in particulate matter, and a nearly 5% reduction in CO₂ emissions. At an economic level, it was found that, despite a CAPEX of nearly USD 1.9 million, scrubber installation provides an average annual net saving exceeding USD 8.2 million. From the deterministic and probabilistic analyses performed, including Monte Carlo simulations under various fuel price correlation scenarios, scrubber installation consistently shows high profitability, with NPVs surpassing USD 70 million and payback periods under four months. Full article