Search Results (685)

Plastic waste accumulation is one of the most pressing environmental challenges of the 21st century, owing to the widespread use of synthetic polymers and the limitations of conventional recycling methods. Among available strategies, chemical upcycling via depolymerization has emerged as a promising circular approach that converts plastic waste back into valuable monomers and chemical feedstocks. This article provides an in-depth narrative review of recent progress in the upcycling of major plastic types such as PET, PU, PS, and engineering plastics through thermal, chemical, catalytic, biological, and mechanochemical depolymerization methods. Each method is critically assessed in terms of efficiency, scalability, energy input, and environmental impact. Special attention is given to innovative catalyst systems, such as microsized MgO/SiO₂ and Co/CaO composites, and emerging enzymatic systems like engineered PETases and whole-cell biocatalysts that enable low-temperature, selective depolymerization. Furthermore, the conversion pathways of depolymerized products into high-purity monomers such as BHET, TPA, vanillin, and bisphenols are discussed with supporting case studies. The review also examines life cycle assessment (LCA) data, techno-economic analyses, and policy frameworks supporting the adoption of depolymerization-based recycling systems. Collectively, this work outlines the technical viability and sustainability benefits of depolymerization as a core pillar of plastic circularity and monomer recovery, offering a path forward for high-value material recirculation and waste minimization. Full article

Carbon fiber-reinforced polymer (CFRP) laminates have been widely coated on aged and damaged structures for recovering or enhancing their structural performance. The health conditions of the coated composite structures have been given high attention, as they are critically important for assessing operational safety and residual service life. However, the current problem is the lack of an efficient, long-term, and stable monitoring technique to characterize the structural behavior of coated composite structures in the whole life cycle. For this reason, bare and packaged fiber Bragg grating (FBG) sensors have been specially developed and designed in sensing networks to monitor the structural performance of CFRP-coated composite beams under different loads. Some optical fibers have also been inserted in the CFRP laminates to configure the smart CFRP component. Detailed data interpretation has been conducted to declare the strengthening process and effect. Finite element simulation and simplified theoretical analysis have been conducted to validate the experimental testing results and the deformation profiles of steel beams before and after the CFRP coating has been carefully checked. Results indicate that the proposed FBG sensors and sensing layout can accurately reflect the structural performance of the composite beam structure, and the CFRP coating can share partial loads, which finally leads to the downward shift in the centroidal axis, with a value of about 10 mm. The externally bonded sensors generally show good stability and high sensitivity to the applied load and temperature-induced inner stress variation. The study provides a straightforward instruction for the establishment of a structural health monitoring system for CFRP-coated composite structures in the whole life cycle. Full article

At present, the construction industry has not yet fully optimized the integration of the potential of big data. Past studies signaled the potential benefits of integrating building information management (BIM) and big data in the field of sustainable building management (SBM). However, these studies have a monotonous perspective in identifying the development of BIM and big data applications in SBM. Therefore, this paper aims to explore BIM and big data from various perspectives in the field of SBM to identify the aspects where additional efforts are required and provide insights into future directions, and it adopts a mixed method of quantitative and qualitative analysis, including bibliometric analysis and knowledge mapping, providing a macro-overview of the research status and development trends of BIM and big data integration for SBM from multiple bibliometric perspectives. The results indicate the following: (1) the current studies on BIM and big data integration (BBi)-aided SBM mainly focused on data integration and interoperability for collaboration, development of information technologies and emerging technologies, data analysis and presentation, and green building and sustainability assessment; (2) the longitudinal analysis of three time-slice phases (2010–2014, 2015–2018, and 2019–2024) over the past 15 years indicates that the studies on BBi-aided SBM have been expanded from the application of BIM in construction projects to the integration and interoperability of BIM with information technology, the integration of virtual models with physical buildings, and sustainable management throughout the building life cycle stages; and (3) key research gaps and emerging directions include data integration and model interoperability across the building life cycle, model transferability in the application of technology, and a comprehensive sustainability assessment framework based on the whole building life cycle stages. Full article

Climate change is becoming one of humanity’s major concerns. Remarkable steps are being implemented to reduce global emissions in all economic sectors, including the built environment. Historical buildings use a considerable amount of energy and produce emissions; therefore, retrofitting these buildings will enhance the global path towards zero-emissions targets. This paper applies a systematic literature review methodology to identify the research around energy efficiency retrofit in historical buildings, then analyzes this data to find out the common scopes of these studies. After that, the study focuses on the research that covered the life cycle assessment. Lastly, the paper identifies where the research in this field stands, what is accomplished, and what needs to be done. The study used two databases, ScienceDirect and the Web of Science. The output of this study that evaluated 362 publications showed that research in historical building energy efficiency has increased significantly in the last ten years. A few studies cover the topic of whole life cycle assessments and mainly focus on specific processes: energy/emissions, or specific suggested interventions. The suggested future plans for research in this area are to consider the whole life energy and emissions in retrofitted historical buildings. Full article

With China’s high-speed rail network undergoing rapid expansion, turnouts constitute critical elements whose safety and stability are essential to railway operation. At present, the efficiency of wheel–rail force safety monitoring conducted in the small hours reserved for the construction and maintenance of operating lines without marking train operation lines is relatively low. To enhance the efficiency of turnout safety monitoring, in this study, a three-dimensional BIM model of the No. 42 turnout was established and a corresponding wheel–rail force monitoring scheme was devised. Collision detection for monitoring equipment placement and construction process simulation was conducted using Navisworks, such that the rationality of cable routing and the precision of construction sequence alignment were improved. A train wheel–rail force analysis program was developed in MATLAB R2022b to perform signal filtering, and static calibration was applied to calculate key safety evaluation indices—namely, the coefficient of derailment and the rate of wheel load reduction—which were subsequently analyzed. The safety of the No. 42 turnout and the effectiveness of the proposed monitoring scheme were validated, theoretical support was provided for train operational safety and turnout maintenance, and technical guidance was offered for whole-life-cycle management and green, sustainable development of railway infrastructure. Full article

Lampreys are primitive fish that rely significantly on olfactory cues throughout their complex life cycle. The olfactory system of the sea lamprey (Petromyzon marinus) is among the best characterized in vertebrates. In recent decades, tremendous advances have been made by isolating individual compounds from sea lampreys that can replicate natural behavior when artificially applied in the wild. In no other aquatic vertebrate has the olfactory ecology been described in such extensive detail. In the first section, we provide a comprehensive review of olfactory behaviors induced by specific, individual odorants during every major developmental stage of the sea lamprey in behavioral contexts such as feeding, predator avoidance, and reproduction. Moreover, pheromonal inputs have been shown to induce neuroendocrine responses through the hypothalamic-pituitary-gonadal axis, triggering remarkable developmental and physiological effects, such as gametogenesis and increased pheromone release. In the second section of this review, we describe a hypothetical endocrine signaling pathway through which reproductive fitness is increased following pheromone detection. In the final section of this review, we focus on the neuronal circuits that transform olfactory inputs into motor output. We describe specific brain signaling pathways that underlie odor-evoked locomotion. Furthermore, we consider possible modulatory inputs to these pathways that may induce plasticity in olfactory behavior following changes in the external or internal environment. As a whole, this review synthesizes previous and recent progress in understanding the behavioral, endocrine, and neuronal responses of lampreys to chemosensory signals. Full article

Construction projects still face persistent barriers to adopting whole life costing (WLC), such as fragmented data, a lack of standardization, and inadequate tools. This study addresses these limitations by proposing a core ontology for WLC, developed using an ontology design science research methodology. The ontology formalizes WLC knowledge based on ISO 15686-5 and incorporates professional insights from surveys and expert focus groups. Implemented in web ontology language (OWL), it models cost categories, temporal aspects, and discounting logic in a machine-interpretable format. The ontology’s interoperability and extensibility are validated through its integration with the building topology ontology (BOT). Results show that the ontology effectively supports cost breakdown, time-based projections, and calculation of discounted values, offering a reusable structure for different project contexts. Practical validation was conducted using SQWRL queries and Python scripts for cost computation. The solution enables structured data integration and can support decision-making throughout the building life cycle. This work lays the foundation for future semantic web applications such as knowledge graphs, bridging the current technological gap and facilitating more informed and collaborative use of WLC in construction. Full article

Remotely sensed cropland abandonment monitoring is crucial for providing spatially explicit references for maintaining sustainable agricultural practices and ensuring food security. However, abandoned cropland is commonly detected based on multi-date classification or the dynamics of a single vegetation index, with the interactions between vegetation and soil time series often being neglected, leading to a failure to understand its full-life-cycle succession processes. To fill this gap, we propose a new full-life-cycle modeling framework based on the interactive trajectories of vegetation–soil-related endmembers to identify abandoned and reclaimed cropland in Jinan from 2000 to 2022. In this framework, highly accurate annual fractional vegetation- and soil-related endmember time series are generated for Jinan City for the 2000–2022 period using spectral mixture models. These are then used to integrally reconstruct temporal trajectories for complex scenarios (e.g., abandonment, weed invasion, reclamation, and fallow) using logistic and double-logistic models. The parameters of the optimization model (fitting type, change magnitude, start timing, and change duration) are subsequently integrated to develop a rule-based hierarchical identification scheme for cropland abandonment based on these complex scenarios. After applying this scheme, we observed a significant decline in green vegetation (a slope of −0.40% per year) and an increase in the soil fraction (a rate of 0.53% per year). These pathways are mostly linked to a duration between 8 and 15 years, with the beginning of the change trend around 2010. Finally, the results show that our framework can effectively separate abandoned cropland from reclamation dynamics and other classes with satisfactory precision, as indicated by an overall accuracy of 86.02%. Compared to the traditional yearly land cover-based approach (with an overall accuracy of 77.39%), this algorithm can overcome the propagation of classification errors (with product accuracy from 74.47% to 85.11%), especially in terms of improving the ability to capture changes at finer spatial scales. Furthermore, it also provides a better understanding of the whole abandonment process under the influence of multi-factor interactions in the context of specific climatic backgrounds and human disturbances, thus helping to inform adaptive abandonment management and sustainable agricultural policies. Full article

With the development of global digital economy and the digital transformation of enterprises, the demand for cross-border cross-domain sharing and circulation of highly sensitive and high-value data assets is becoming more and more obvious. In the process of shared circulation, data assets are faced with some problems, such as unreliable communication network, uncontrollable cloud storage service, untrusted participants and so on, which leads to data tampering, stealing, blocking and tracing back to the source. However, the existing security protection means are difficult to systematically ensure the safe circulation and utilization of data assets in an uncontrolled, high threat and strong confrontation environment. Therefore, this paper establishes a security protection model of data assets in the whole life cycle with cryptography technology as the core, and designs a security technical framework that runs through each link of data asset sharing and circulation. In addition, an architecture design scheme of data asset security sharing and circulation system based on cryptography service technology is proposed, which can systematically solve the security problem of data asset sharing and circulation in uncontrolled environments, and can improve the ability of on-demand deployment, flexible access and dynamic adjustment while maximizing the security of data assets. Full article

Life-cycle cost assessment has gained increasing relevance across sectors related to urban and building development. In real estate and public procurement decision-making, it offers a comprehensive view of property costs beyond the initial investment, which aligns with European Sustainable Development policies and new taxonomies in sustainable investment. Life-cycle cost assessment supports sustainable design decisions by integrating multiple perspectives and methodologies, including Whole Life Costing and Net Present Value calculations. This approach enables a comprehensive evaluation of long-term costs and benefits, assessing their impact on economic viability and profitability throughout the investment life cycle. However, several challenges persist in standardizing methodologies, developing comprehensive data inventories, and ensuring consistency in result interpretation. The absence of universally accepted frameworks and guidelines introduces additional limitations for practitioners, including estimation inaccuracies, biased assessments, unreliable probability judgments, and the neglect of indirect consequences in decision-making. This review particularly emphasizes the need for interdisciplinary research to advance the integration of costs and benefits of externalities and intangibles associated with social and environmental criteria. Full article

The public–private partnerships (PPP) mode is very popular in public infrastructure projects. The PPP model for sponge city construction (SCC) provides an effective way to curb and manage the increasingly serious ecological water problems in China. The quantitative evaluation of value for money (VFM) is an evaluation method that obtains quantitative values through a certain calculation process. However, the current studies lack a dynamic quantitative evaluation of VFM for the entire life cycle of SCC PPP projects, and cannot observe the impact of key factors on the VFM value. By constructing a system dynamics (SD) model for the VFM quantitative evaluation of SCC PPP projects from the perspective of the whole life cycle, this study can intuitively and transparently observe the impact of key factors (such as discount rate and profit margin) on the evaluation results and feasibility of adopting a PPP model in the project, offering policymakers a tool to mitigate the risks of “Pseudo-PPP” projects. After collecting cases in Anhui province from the China PPP Center, this study constructed a life cycle VFM quantitative evaluation system dynamics model suitable for SCC PPP projects that consist of the public sector comparison (PSC) value and PPP value. The results indicate that the system dynamics model can be effectively applied to the dynamic quantitative evaluation of SCC PPP projects and clarify the influence degree on and sensitivity of various factors to the VFM value. Specifically, when the discount rate increases, the decrease in the PPP value is greater than that in the PSC value, leading to an increase in the VFM value. Moreover, a reasonable profit margin is more sensitive to the VFM value and decreases as the reasonable profit margin increases. In addition, choosing different availability service fee calculation methods will result in varying the adjustment range to a reasonable profit margin that drives the adoption of VFM quantitative evaluation. These research findings have provided a viable dynamic research methodology for the quantitative VFM evaluation of SCC PPP projects. This methodology enables the dynamic visualization and easy determination of the acceptable ranges for relevant factors, offers rational policy recommendations for the quantitative evaluation of key factor values, and thereby effectively prevents PPP project violations, promoting fair and reasonable cooperation between governments and private enterprises. Full article

Fuel cell electric vehicles (FCEVs) offer a promising solution for energy saving and emission reduction in transportation. However, several challenges must be addressed for their application. This study conducts a full life cycle assessment (LCA) of FCEVs, dividing it into the fuel cycle and vehicle cycle to separately assess energy consumption (EC) and emissions. The fuel cycle examined 18 hydrogen production–storage–transport pathways, while the vehicle cycle evaluates energy use and emissions associated with vehicle component production, assembly, disposal, battery production, and fluid consumption. Based on the GREET database, total energy consumption and emissions over a lifetime were calculated. Five environmental impact indicators were used for evaluation, and a comprehensive environmental assessment (CEA) indicator was established for different scenarios. Results indicate that nuclear thermochemical water splitting is the best hydrogen production method, and pipeline transportation is the most efficient for hydrogen transport. Additionally, water electrolysis for hydrogen production is only practical when paired with renewable energy. The study also identified that the Hydrogen production method, “Body”, “Proton Exchange Membrane Fuel Cells (PEMFCs) System”, “Chassis”, “Hydrogen Storage System” and lifetime significantly impact energy consumption and emissions. These stages or products represent high-impact leverage points for enhancing the lifecycle sustainability evaluation of FCEVs. Full article

Laminated Veneer Lumber (LVL) presents an alternative material for offshore wind turbine towers and blades for an energy sector whose greenhouse gas emissions are substantial. In compliance with AS/NZS 4536, this case study facilitates a specifications’ selection framework that embraces a validated, cost–benefit determination via life cycle cost analyses (LCCA) specification comparisons. A structured consultation with three key Western Australian offshore industry experts, compliant with a standard phenomenological qualitative approach, further facilitates offshore wind turbine (OWT), LCCA cost comparisons between traditional steel and fibreglass components and LVL wooden components. LVL is found to have a higher capital cost but can generate long-term savings of AUD 30,400 per comparable unit less than Traditional OWT specifications, noting a 5% lower LVL operation and maintenance cost. Where decommissioning recycling facilities exist, OWT LVL specification components are encouraged. This work argues that LVL options uptake in Western Australia (WA) is both practicable and whole-cost effective. Full article

To address the high complexity layout optimization problem of an offshore wind and wave energy co-generation system, an improved seagull optimization algorithm-based method is proposed. Firstly, the levelized cost of electricity (LCOE) model, based on the whole-life-cycle cost, serves as the optimization objective. Therein, the synergistic effect between wind turbines and wave energy generators is taken into consideration to decouple the problem and establish a two-layer optimization framework. Secondly, the seagull optimization algorithm is enhanced by integrating three strategies: the nonlinear adjustment strategy for control factors, the Gaussian–Cauchy hybrid variational strategy, and the multiple swarm strategy, thereby improving the global search capability. Finally, a case study in the South China Sea validates the effectiveness of the model and algorithm. Using the improved algorithm, the optimal layout of the co-generation system and the optimal wind turbine parameters are obtained. The results indicate that the optimized system achieves a LCOE of 0.6561 CNY/kWh, which is 0.29% lower than that achieved by traditional algorithms. The proposed method provides a reliable technical solution for the economic optimization of the co-generation system. Full article

In the field of mining transportation, methanol range-extended powertrain systems are emerging as the preferred solution to address heavy-duty transport challenges in mining areas, leveraging their low-carbon emissions and long-range endurance. However, conventional energy storage technologies face trade-offs between energy density, power density, and cycle life: lithium-ion batteries (Li-ion) have a high energy density but short cycle life, while supercapacitors (SCs) have a high power density and long cycle life but low energy density. To address these limitations, a hybrid energy storage system (HESS) combining Li-ion and supercapacitors (SCs) is proposed as the energy storage unit for the methanol range-extended mining truck (MRMT) in this study. Firstly, the power architecture of MRMT with HESS is designed. Then, the range-extender, Li-ion battery, and SCs are matched and selected based on the operating conditions of the mining truck. Finally, a whole vehicle energy management strategy is developed, and the vehicle power system performance is simulated by combining MATLAB/Simulink (R2022a) with AVL-Cruise (R2019.2). Comparison with conventional single Li-ion range-extender system reveals that the MRMT with HESS reduces methanol consumption by 6.4% and extends the cycle life of Li-ion by 353.4%. This study provides a technological path for the green transformation of mine transportation that is both economical and sustainable. Full article