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Spatiotemporal estimation of construction and demolition waste generation using novel integrated machine learning and remote sensing approaches: A study of 83 Chinese cities
No full textA widely recognized challenge hindering effective waste management planning worldwide is a lack of systematic and continuous data on construction and demolition waste (CDW) generation. To address these critical data limitations, this study presents its first systematic effort to integrate remote sensing (RS) data into a machine learning (ML)-based framework for estimating CDW generation. Utilizing all currently available data collected from selected Chinese cities, four widely used ML algorithms were trained and evaluated: Random Forest (RF), Gradient Boosting Decision Trees (GBDT), Light Gradient Boosting Machine (LightGBM), and Extreme Gradient Boosting (XGBoost) using three feature groups: statistical variables, RS variables, and a combination of both. The best-performing models were applied to an interpolation dataset covering 83 Chinese cities over a 10-year period to evaluate their spatiotemporal extrapolation capabilities and generalizability. The results consistently indicate that models based solely on RS features outperform those using only statistical data or combined feature sets, with R² values ranging from 0.77 to 0.81 across all four algorithms. Among these, the RF model exhibited the highest overall performance, while LightGBM and XGBoost also delivered competitive results. Analysis of CDW generation across 83 Chinese cities revealed distinct spatial hotspots in regions such as the Yangtze River Delta and the Pearl River Delta, with a noticeable inland expansion trend over time, reflecting China's national strategies for promoting balanced regional development. This study offers a novel, scalable, and transferable approach that expands the methodological boundary of CDW estimation beyond conventional statistical data, offering new insights and practical implications for global CDW management, particularly in rapidly urbanizing or data-scarce regions
Reviews and syntheses:Carbon vs. cation based MRV of Enhanced Rock Weathering and the issue of soil organic carbon
No full textWe discuss the “monitoring, reporting and verification” (MRV) strategy of Enhanced Weathering (EW) based on carbon accounting and argue that in open systems such as arable land, this approach is ill-suited to close the balance of all carbon fluxes. We argue for total alkalinity (TA) as the central parameter for the carbon based MRV of EW. However, we also stress that tracking alkalinity fluxes using a systems-level approach is best done by focusing on charge balance maintenance through time. We start by explaining the concept and history of alkalinity conceptualization for the oceans. The same analytical method first proposed for the oceans-titration with a strong acid-is now commonly used for porewaters in agricultural soils. We explain why this is an accurate analysis for ocean water and why it is unsuitable to record TA for porewaters in agricultural soils. We then introduce an alternative MRV based on cation accounting and finally discuss the fate of cations released from the weathering of basalt, soil cation dynamics and close by suggesting open research questions.</p
Generating Older Active Lives Digitally (GOALD): Exploring Older Adults’ Views of Digital Technology for Physical Activity
No full textBackground: The use of digital technology for supporting physical activity (PA) in older adults has increased recently despite the paucity of research exploring perceptions and age-appropriateness of these technologies. Methods: Older adults (n = 120) residing in care homes (n = 45) and living independently (n = 75) in England and Scotland, as well as care home staff (n = 30) and young adults (n = 7) appraised a variety of different PA technologies (eg, online and digital platforms, exergames, and virtual reality headsets) through a multiphase approach. Technologies were presented as a “menu” to participants to select at interactive sessions. Feedback was collected through focus groups, interviews, codesign workshops, and field notes, all analyzed thematically. Participant characteristics including PA levels and familiarity with technology were collected via questionnaire at baseline and after appraising selected technologies. Results: Qualitative findings explored 6 overarching themes: (1) recognizing the potential of technology, (2) suitability of PA technology, (3) barriers to using PA technology, (4) motivation to engage with digital technology, (5) content suggestions for future PA technology, and (6) preferences for PA technology delivery. PA engagement and prior experience with digital technologies varied greatly at baseline. Overall, participants’ perceptions and appraisal of the PA technologies varied according to their context and setting, prior experience with technology, and PA engagement. Quantitative data were challenging to gather, with complete data available from only 18% out of those consented. Conclusions: Older adults in this study demonstrated a keen interest in digital technologies for PA, but context- and health-related barriers for engagement with these tools need addressing
Defining new approaches for retrofit life cycle analysis to improve design outcomes
No full textDomestic retrofit is well established as a means of reducing energy consumption in buildings and therefore mitigating climate change. However when life cycle carbon, i.e. carbon impacts associated with the retrofit materials is considered, the life cycle carbon benefit remains under-developed. Wider uptake of retrofit life cycle analysis (LCA) at the design stage would ensure that maximum energy and carbon efficiencies are being achieved both at an individual building and a global scale. Yet robust guidance for retrofit LCA does not exist, and so any LCA delivered at present is subject to much interpretation by the analyst. This paper considers the well-regarded guidance ’Whole life carbon assessment for the built environment, 2nd edition’ [1], and evaluates its usefulness to retrofit LCA. The research presented here finds that a more specific approach for life cycle carbon and energy analysis of retrofit is required. The RICS approach addresses only carbon analysis and so can easily overlook the advantages of energy demand reductions; many of the default values are unsuitable for a small-scale project like a domestic retrofit; and the method for deriving uncertainty could provide false confidence to users. Instead, to ensure that life cycle analysis outcomes can be pinpointed to retrofit measures with minimal conflating factors, carefully considered deviations and amendments are proposed. This specificity ensures that results can be used to hone a retrofit design, leading to better life cycle design decision making, facilitate development of a high quality retrofit life cycle dataset, build confidence in understanding retrofit life cycle general trends, enable better strategic and policy level decisions, and importantly, reduce life cycle carbon and energy impacts of retrofit. Ultimately, the redefined LCA approach proposed in this paper, specifically for retrofit, with parameters focused on thermal performance, lays the foundations for a new standard for retrofit life cycle studies
A Self-Levelling railway sleeper concept and its large-scale testing
No full textRailway track transition zones present engineering challenges due to their abrupt change in stiffness between structural elements such as embankments, bridges and tunnels affecting track geometry parameters. Although a variety of stiffness-based remedial measures have been widely applied, their implementation can be constrained by high capital cost, operational disruption, and the complexities associated with modifying the substructure. As a result, interventions in practice commonly focus on controlling permanent deformations and differential settlement, particularly related to the development of hanging sleepers. Thus, this study investigates the use of modular self-levelling sleepers (SLS) as a solution. To do so, two concept SLS systems are designed and developed: one employing a granular mechanism (SLS-G), and the other based on a horizontally acting wedge mechanism (SLS-HW). Both variants use the polymeric sleepers and are designed for compatibility with conventional ballasted track systems. Experimental laboratory testing is undertaken, and it is found that the SLS prototypes were able to restore the sleeper-ballast contact for voids up to 40 mm depth, while stress measurements at the interface indicated improved load distribution under the rails. The findings support the proof-of-concept that self-levelling sleepers have the potential to be a modular, low-disruption solution for mitigating track geometry degradation and reducing maintenance requirements at transition zones
Buckling behavior of UHPC filled stainless steel tubular columns subjected to eccentric compression
No full textUltra-high Performance Concrete (UHPC) filled stainless steel tubular (UHPCFSST) column is a new type of concrete filled steel tubular (CFST) composite columns prospective to be adopted in offshore construction. As a follow-up work of previous study focusing on concentric behavior and interfacial properties, this paper delves into the eccentric compressive behaviour of UHPCFSST columns through experimental investigation and analytical derivation. A total of 10 UHPCFSST column specimens varying in slenderness ratio, tube diameter-to-thickness ratio and load eccentricity ratio were tested to explore the load-deformation response, damage pattern, stiffness, ductility and load-carrying capacity under eccentric compressive loading. Moreover, in-depth analysis was conducted to provide deep insight into the composite action between stainless steel tube and UHPC. To promote the application of UHPCFSST columns in practice, current international design codes of conventional CFST columns were comparatively reviewed for the prediction of axial force-bending moment (N-M) interaction diagram. In view of the limitation of current methods, an improved approach with consideration of confinement effect and UHPC tensile strength was proposed to assist the design of UHPCFSST columns
Techno-economic evaluation of emission control configurations for AMP/PZ-based post-combustion CO₂ capture
No full textMinimizing the environmental impacts of amine-based post-combustion carbon capture technologies is essential for regulatory compliance and public acceptance. Experimental campaigns at RWE's CO2 capture pilot plant in Niederaussem using CESAR1 demonstrated that combining existing emission abatement technologies can substantially reduce the concentration of amines and degradation products in the CO2-depleted flue gas to below the detection limit of an infrared spectrometer. The campaign confirmed that a proprietary dry bed technology (OEASE aerozone™) or a second water wash can reduce AMP and PZ emissions to below 1 mg/Nm3. However, an acid or chemically active wash downstream of the water wash is necessary to reduce NH3 emissions to very low levels (<2 mg/Nm3). Combining a dry bed with an acid wash significantly reduces both the required acid solution and the resulting acid waste. The techno-economic analysis indicates that implementing emission mitigation technologies provides substantial environmental benefits for the CESAR1 process, with only a marginal increase (<1 €/tCO₂) in both the carbon capture cost (CCC) and CO₂ avoidance cost (CAC). The additional capital cost associated with extra column packing is offset by operational cost savings from reduced solvent losses. For stringent emission permits targeting NH₃, a configuration combining a dry bed upstream of the water wash followed by an acid wash achieves the best balance between emission control and cost efficiency. This configuration results in a Levelized Cost of Electricity (LCOE) of 143 €/MWh, a CCC of 45.4 €/tCO₂, and a CAC of 88.4 €/tCO₂.</p
PVT and Phase Behavior of Petroleum Fluids
No full textFlow assurance can be expressed as the coupling of multiphase flow and fluid phase behavior. It requires understanding multiphase flow as well as fluid properties, fluid compositions, pressure-volume-temperature (PVT) characteristics, and other fluid phase behavior from the reservoir to the downstream processing facility through the life of the field to prevent upset conditions. A good understanding of the phase behavior and fluid properties allows a flow assurance engineer to develop technically feasible and economically optimal set of strategies to overcome a variety of flow assurance problems, ensuring a successful and safe operation. In this chapter, after a short review of the nature and chemistry of petroleum fluids, the thermodynamic behavior of pure compounds and the various types of reservoir fluids will be described. A section is then dedicated to laboratory thermodynamic experiments such as PVT analysis and finally some empirical correlations and equations of state used to simulate the phase behavior of the hydrocarbons and calculate thermophysical properties will be presented.</p
University–industry collaboration in post-Soviet states: A bibliometric study with implications for educational policy and practice
No full textUniversity–industry collaboration has become an essential mechanism not only for fostering innovation and economic development but also for shaping the educational missions of universities. In post-Soviet states, however, University–Industry Collaboration has evolved within a distinctive context marked by the legacies of centrally planned economies, state dominance, and systemic transition, creating both structural barriers and new opportunities for higher education reform. This study conducts a bibliometric review of University–Industry Collaboration research in post-Soviet states between 1991 and 2024, complemented by a thematic analysis of selected studies. Using a dataset of 223 publications drawn from the Web of Science and applying co-citation analysis, bibliographic coupling, and thematic mapping, the study identifies the intellectual foundations, collaborative networks, and key thematic clusters shaping the field. The findings reveal five persistent challenges—state dominance, weak industry demand, underdeveloped commercialization infrastructure, human capital constraints, and cultural barriers—alongside emerging opportunities for curriculum reform, work-based learning, and employability-focused teaching models. Beyond mapping the research landscape, the study shows how University–Industry Collaboration intersects with higher education by reshaping curricula, influencing academic roles, and expanding student engagement with industry. These insights extend current debates by situating the post-Soviet experience within broader discussions of educational change, institutional reform, and the pedagogical implications of university–industry partnerships
Is Omni-Channel Retailing the Future of Luxury Fashion Brands?
No full textIn the contemporary digital era, the rapid development of new technology and technological innovation, especially in the fields of artificial intelligence, augmented reality, virtual reality, multifunctional social media and e-commerce have completely altered consumers’ lifestyles and their communication and consumption behaviour. Therefore, in order to achieve sustainable success and satisfy these consumers’ needs in terms of psychological and functional benefits, retailers, including luxury fashion brands, need to implement advanced technology in their branding strategies, marketing communication and distribution strategies (Passavanti et al., 2020; Pantano et al., 2022). That they are already doing so is evidenced by the increasing number of luxury fashion brands which have developed multiple channel distribution strategies and phygital consumer experiences (a term referring to overall experiences across online and offline experiences) to create interactive experiences through the combination of digital channels with brick-and-mortar stores (Hyun et al., 2022; Bartoli et al., 2023)
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