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Variation of SARA fractions of crumb rubber modified asphalt binder-aggregate interface system and its correlation with adhesion properties
No full textPublisher Copyright: © 2024 Elsevier LtdThe incorporation of rubber powder leads to a high degree of complexity in the CRMA binder-aggregate interfacial properties, which directly affects the interfacial adhesion performance. The objective of this study is to investigate the variation of SARA fractions of CRMA binder during the adhesion process and to explore the intrinsic relationship between the components and the adhesion properties. To this end, the staged extraction tests were performed to extract CRMA binder layers on the aggregate surface. After each extraction, the binder layer was evaluated in terms of its SARA fraction contents and molecular weight distribution. Additionally, the pull-off tensile strength (POTS) was used to assess the adhesion of the binder-aggregate interface through the binder bond strength (BBS) test. Finally, the correlation between the SARA fractions of CRMA binder and interface adhesion of CRMA binder-aggregate system was analyzed. The results showed that the CR tends to absorb the lighter components of base asphalt, the variations in SARA fractions and molecular weight distribution during the aggregate adhesion to CRMA binders occurred mainly in the third and fourth elution layers. Pen 70 CRMA binder and limestone show the best adhesion properties among all the binder and aggregate types. The increase in CR size and the decrease in CR dosage are favorable for the adhesion of CRMA binders to aggregates. Furthermore, asphaltenes and resins are positively correlated with adhesion, while aromatics and saturants are negatively correlated with adhesion. The correlation between SARA content and adhesion varied depending on the aggregate type.Peer reviewe
Improving port state control through a transfer learning-enhanced XGBoost model
No full textPublisher Copyright: © 2024 Elsevier LtdWith the advancements in modern information technology, Port State Control (PSC) inspections, as a crucial measure to protect ship safety and the marine environment, are undergoing an intelligent transformation. This paper aims to streamline the selection process for inspecting high-risk ships by employing a data-driven model to predict the number of deficiencies in ships arriving at ports. A transfer learning-enhanced eXtreme Gradient Boosting (XGBoost) model is proposed by innovatively incorporating sample similarity calculations to adapt the model to the unique characteristics of the target port. This novel model enables the integration of relevant data from other ports, enhancing the predictive performance of the model to specific port conditions. Utilizing PSC inspection records from ports within the Tokyo Memorandum of Understanding (MoU) and choosing the port of Singapore as the target, numerical experiments demonstrate that the proposed model achieves improvements of 1.81 %, 6.08 %, and 3.60 % in the mean absolute error, mean squared error and root mean squared error, respectively, compared to the standard XGBoost model. Furthermore, across various sizes of training samples, the proposed model outperforms other machine learning models. This work may service as a significant step towards exploring the potential of developing data-driven models based on comprehensive data to assess the risk level of foreign ships arriving at ports, ameliorating the PSC inspection process by aiding PSC officers in identifying substandard ships more effectively.Peer reviewe
An environmental and economic investigation of shipping network configuration considering the maritime emission trading scheme
No full textFunding Information: This work was supported by National Natural Science Foundation of China [grant number 72004132], Science and Technology Commission of Shanghai Municipality [grant number 21692195200], Education Commission of Shanghai Municipality [grant number 2022ZKNH013]. We are appreciative of their support. The authors also thank the guest editors, editors and anonymous reviewers for their valuable suggestions and comments. Funding Information: This research work is supported by National Natural Science Foundation of China [grant number 72004132 ], Science and Technology Commission of Shanghai Municipality [grant number 21692195200 , 23692111100 ], Education Commission of Shanghai Municipality [grant number 2022ZKNH013 ]. Publisher Copyright: © 2024 Elsevier LtdDecarbonization is currently an urgent issue for the international shipping industry. The maritime Emission Trading Scheme (METS) is an effective measure, while the utilization of the Arctic Northeast Passage (NEP) and carriers' profit-driven reactions may affect its effectiveness. Thus, this paper proposed an optimization model to investigate the carrier's economic viability and the CO2 emission under METS for the SCR/NEP-combined liner shipping service. Various METS scenarios are set based on 1) geographical scope (GS), 2) free emission quota percentage (FEQP), and 3) carbon price (CP). Results show that METS would guarantee a short-term CO2 emission reduction within the GS, but the volume of overall CO2 emission in some scenarios would be even larger. In individual cases, METS positively affects the carrier's economic viability. METS disincentivizes carriers to use the NEP, especially when it is implemented in the Arctic area or with high pricing. For carriers, the main countermeasure to cope with METS is slow steaming in the GS. Some valuable insights for policymakers designing METS: it is not the case that the higher the value of GS/FEQP/CP, the better the overall CO2 emission reduction effect. A moderate GS and CP may be appropriate for balancing carriers' economic benefits and emission reduction efficiency, in whole or in part. FEQP can be set relatively low at the start of METS and raised gradually to motivate the carriers in emission control.Peer reviewe
Embodying Homescapes: Biocostume as a mode of more-than-human encounter with place
No full textThis interview with costume designer Ingvill Fossheim explores notions of home as a relational and embodied experience where more-than-human places are entangled with ecosomatic perception, materiality, performativity and belonging. It builds on the idea of relational materialities embedded in ecoscenography—a philosophical and practical approach to theatre and performance design which embraces ecological ways of thinking and doing both within and beyond the performing arts. The conversation explores how biobased costume design can be explored as a relational act of embodying home where more-than-human actants are co-entangled and co-complicit in each other’s making. Using Fossheim’s design for Muohtadivggažat (The Sound of Snow) by Ferske Scener and The Sámi National Theatre Beaivváš (premiere 23.6.2021, Sápmi/Norway) as a case study, the interview examines biocostume as a relational praxis that fosters a sense of kin with our co-extensive selves. Subarctic mountain birches and pine trees from Fossheim’s childhood home in Sápmi/Norway provided bark and cones for dyeing and mordanting the costumes and the fishbone pearls, while woollen costumes were coloured with locally foraged Cortinarius mushrooms. These explorations in material co-entanglement promote new considerations of performance design, where embodying home becomes one of partnering with place to uncover the abundance and complexity of more-than-human possibilities.Peer reviewe
Robust localization of shear connectors in accelerated bridge construction with neural radiance field
No full textPublisher Copyright: © 2024Accelerated bridge construction (ABC) demands precise alignment of prefabricated members to prevent assembly failure. Conventional methods struggle to localize shear connectors from point cloud data (PCD) generated by structure-from-motion due to its sparsity. This paper introduces a robust method for shear connector localization using PCD generated by a neural radiance field and a three-step narrowing-down algorithm. The PCD exhibits densely populated points for small connectors, allowing the algorithm to pinpoint their locations accurately. The method successfully identified all 72 shear connectors in a mock-up prefabricated girder, with an average error of 10 mm, demonstrating its potential for assessing constructability in ABC projects. Future research may integrate deep learning-based segmentation techniques to enhance efficiency and adaptability in complex geometries and non-standard bridge designs.Peer reviewe
Acrylamide/Alyssum campestre seed gum hydrogels enhanced with titanium carbide: Rheological insights for cardiac tissue engineering
No full textThis study investigates the use of acrylamide and Alyssum campestre seed gum (ACSG) to create hydrogel composites with enhanced electrical and mechanical properties by incorporating titanium carbide (TiC). The composites were analyzed through techniques such as FTIR, SEM, TEM, TGA, swelling, rheology, tensile, electrical conductivity, antibacterial, and MTT assays. XRD analysis showed that 0.5 % TiC NPs were exfoliated in the hydrogel, while 1 % was intercalated. SEM images showed that ACSG created a semi-interpenetrating polymer network with interconnected cavities averaging 9.1 μm, which reduced to 3.6 μm with 0.5%TiC and 51.8 nm with 1%TiC due to increased crosslinking density. TGA results confirmed hydrogel stability at autoclave temperatures. Rheological testing revealed that the hydrogel exhibited a maximum resistance of 317 kPa. The addition of 1 % TiC enhanced its electrical conductivity to 1.5 × 10−2S/cm, making it suitable for applications in cardiac tissue engineering. MTT assays confirmed the hydrogel's biocompatibility and demonstrated its superior antibacterial activity against Staphylococcus aureus compared to Escherichia coli. The AM/ACSG/TiC hydrogel is a promising material for cardiac tissue engineering because of its adjustable mechanical properties, excellent electrical conductivity, and strong compatibility with cell cultures. The addition of ACSG improves the hydrogel's rheological behavior, which is crucial for promoting effective cell growth.Peer reviewe
COLREGs-Adaptive trajectory planning and decision-making in maritime autonomous surface ships
No full textPublisher Copyright: © 2024 Elsevier LtdDecision-making for collision avoidance and trajectory planning are critical technologies for maritime autonomous surface ships. These systems must align with regulatory frameworks such as the International Regulations for Preventing Collisions at Sea (COLREGs) and account for the ship's maneuvering capabilities for effective control and tracking. This study introduces a novel framework integrating regulatory consideration into the path-searching process, enhancing collision avoidance in both COLREG-compliant and non-compliant scenarios. The framework recasts the trajectory-planning problem into an optimal control problem and employs virtual obstacles and spatial–temporal navigation corridors consistent with collision-free decisions as constraints for trajectory optimization, improving navigation efficiency and comfort. The framework is validated through various encounter scenarios, and the results demonstrate that the proposed framework can produce superior collision avoidance decisions, while planning shorter navigation time and smoother collision-free trajectories, significantly improving the collision avoidance capability of maritime autonomous surface ships.Peer reviewe
A revisited verification and validation analysis for URANS simulation of planing hulls in calm water
No full textPublisher Copyright: © 2023 Elsevier LtdVerification and Validation (V&V) is the foremost analysis which is carried out for evaluation of the accuracy level and dependability of computational fluid dynamic (CFD) simulations. The present study investigates the V&V of CFD models in predicting the dynamic trim and hull resistance of high-speed planing hulls with an aim to provide a deeper understanding of V&V analysis in this specific field of application. Two different planing hulls, namely the C05 stepped hull and the C1 interceptor hull, are analyzed with four different grids and time-steps using two mesh motion techniques, namely overset and morphing approach. The discretization (grid) and time-step uncertainties for each CFD simulation are estimated using the least squares method. The results indicate that the overset mesh approach performs better than the morphing grid method in terms of numerical uncertainty and validation achieved for both hulls. The error of both techniques in the prediction of resistance and trim angle of the boat shows an acceptable range of accuracy. The findings provide valuable insights for simulation-based designing and optimizing high-speed planing hulls, specifically by identifying the optimal mesh technique, cell number, and time-step for accurate prediction of wetted surface shape, ventilation formation, running attitude, and resistance.Peer reviewe
Catalytic graphitization of engineered pyrolysis bio-oil for sustainable graphite and hydrogen Co-production
No full textPublisher Copyright: © 2025 The AuthorsThe decarbonization of energy systems requires both clean fuel alternatives and sustainable materials for energy storage. This study explores catalytic graphitization of engineered pyrolysis bio-oil, a renewable, carbon-rich by-product of biomass conversion, to produce graphite for lithium-ion battery anodes and renewable hydrogen. Four engineered bio-oils derived from sawdust pyrolysis at 550 °C were evaluated at 1300 °C using reduced iron powder as a catalyst. Among these, heavy-phase filtered bio-oil (HFB) demonstrated superior graphitization efficiency, achieving a graphitization degree of 94.51% and generating a significant hydrogen yield of 5.25 g H2/100 g bio-oil. Compared to conventional synthetic graphite production, which relies on fossil coke and extreme temperatures (>2500 °C), this method significantly reduces energy demand and CO2 emissions. A liquid–solid catalytic mechanism is proposed for the first time, enabling efficient carbon transformation and hydrogen release without the need for steam input. This work contributes to advancing circular bioeconomy strategies and highlights the role of biomass valorization in future sustainable energy systems.Peer reviewe
Identification of Legionella anisa, Legionella longbeachae and Legionella pneumophila using MALDI-TOF MS : A method validation study with environmental isolates
No full textPublisher Copyright: © 2025 The AuthorsMatrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) allows species-level microbial identification quickly and cost-effectively. The aim of this study was to validate MALDI-TOF MS for the identification of Legionella anisa, Legionella longbeachae and Legionella pneumophila and to examine whether incubation time or sample preparation method affect identification results. Environmental Legionella strains and ATCC reference strains were used in the study. The strains underwent 16S rRNA sequencing and latex agglutination and fluorescence tests to which MALDI-TOF MS results were compared. The strains, incubated for 24 and 48 h, were analysed with MALDI-TOF MS using direct transfer and extraction methods. Following performance characteristics were calculated from the results: sensitivity, specificity, relative accuracy, predictive values, repeatability and reproducibility. Species-level identification was achieved for 63 out of the 69 environmental and reference strains regardless of incubation time or preparation method. MALDI-TOF MS proved to be very specific (100 %) and sensitive (94.6–100 %) to the Legionella species analysed. With the extraction method, incubation time had a statistically significant, but species-dependent effect on the interpretative criteria, i.e. score values, in all species studied. No significant difference in any of the species' score values was found between the direct transfer and extraction methods with 24 h incubation. MALDI-TOF MS score values showed high repeatability (std 0.01–0.23) and reproducibility (std 0.02–0.18) for all Legionella species analysed. Based on the results, MALDI-TOF MS suits well for the analysis of environmental Legionella strains already after 24 h of incubation and using direct transfer method.Peer reviewe