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Stereo digital image correlation (stereo-DIC) technique has received special attention in detection and monitoring for quantifying and monitoring the displacement alterations on the surfaces of historical buildings. However, in the field of structural health monitoring of cultural relic, the method of prefabricating speckle patterns on the monitored object is inappropriate. And the method proposed in several literature sacrifices the scale information or the calibration board is used multiple times. This paper provides a practical and effective deformation monitoring system based on stereo DIC for 3D deformation evaluation of the stern of archaeological wooden shipwreck. To calibrate the stereo camera for archaeological wooden object measurement, a self-calibration is proposed to calibrate extrinsic parameters of fixed cameras using the objects surface shape and texture without using a calibration board and sacrificing scale information. In particular, the deformation monitoring data can be used to compensate for the differences in material properties between mo and archaeological wood. The experiment demonstrated that the proposed deformation monitoring system and self-calibration methods are feasible and accurate. Based on this, the measures displacement fields of the archaeological wooden shipwreck stern are presented, and the material properties of the finite element analysis of the shipwreck during the design of the supporting structure were corrected by the deformation monitoring data. The results show that the proposed method has the advantages of good flexibility, strong applicability, and high precision on 3D structural deformation monitoring and structural design of archaeological wooden relics. [ABSTRACT FROM AUTHOR]

• Determination of cellulose, hemicellulose, and lignin contents of three species of archaeological wood in the Quanzhou Song shipwrecks. • Characterisation of salt-forming elemental compositions of the three species of archaeological wood in the Quanzhou Song Shipwrecks. • Changes in the mechanical properties of the amorphous components (amorphous cellulose, hemicellulose, and lignin) of the three waterlogged archaeological wood samples were compared with those of sound wood based on molecular dynamics simulations. • The molecular mechanisms underlying the effects of soluble salts (sodium chloride) on the mechanical properties of water-soaked archaeological wood were revealed. Sodium chloride (NaCl) is the main soluble salt component of marine waterlogged archaeological wood, and it causes deterioration of wood fibres. In this study, a molecular dynamics simulation of three types of archaeological wood from the Quanzhou Song Shipwreck was employed to investigate the impact of NaCl on the mechanical properties of amorphous components consisting of amorphous cellulose, hemicellulose, and lignin. The findings revealed that water molecules bound to the fibres enhanced the mechanical performance of the woody fibres. However, NaCl affected the stability and mechanical properties of the amorphous components. By using molecular dynamics simulations, 24 sets of amorphous fibre models, consisting of fir, pine, and camphorwood with salt concentrations ranging from 0 % to 7 %, were constructed to further analyse the influence of salt content on the mechanical properties of the amorphous components. The results showed that all three species of archaeological wood exhibited similar trends, with the adsorption energy and radial distribution function between wood fibres and water molecules decreasing with increasing NaCl concentration, leading to the gradual rupture of hydrogen bonds in water molecules. Consequently, more water molecules engage in ion hydration, resulting in an increase in the amount of free water within the amorphous regions. This, in turn, degrades the mechanical properties of the amorphous components. This study contributes significantly to a comprehensive understanding of the mechanical properties of marine archaeological wood and is important for decision-making in studies related to the preservation and evaluation of marine waterlogged wooden artefacts. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The adsorption energy of CO 2 in different crystalline forms of MgO was investigated by MD simulations. • The adsorption performance of CO 2 in different crystalline MgO under different process parameters was experimentally investigated. • The machine learning model predicted the adsorption energy based on salient features and analyzed the degree of contribution of each variable. The effects of the adsorption energy of CO 2 within MgO at different temperatures were investigated by molecular dynamics simulations and experimentally verified. The adsorption mechanism of CO 2 within MgO was discussed and explained qualitatively. The results indicated that the diffusive adsorption of CO 2 by MgO was divided into two stages, and the ability of CO 2 capture by the cubic MgO performed better than that by spherical MgO. The adsorption of CO 2 by the cubic MgO was mainly physical and received the inhibited adsorption behavior at the high-temperature stage (>505 K). Herein, we established a comprehensive dataset of adsorption energies and quantitatively analyzed an adsorption energy prediction model using machine learning techniques. The results demonstrated that Decision Tree Regression (DTR) and K-nearest neighbor (KNN) algorithms offer satisfactory accuracy based on root mean square error (RMSE) and R2 evaluations. This approach enables efficient and precise prediction of adsorption energies without the need for labor-intensive molecular dynamics calculations. Furthermore, we explored the influence of various features (Crystal structure, The number of Mg, The number of CO 2 , Temperature, Pressure, Volume, and Bond energy) on prediction performance. Lastly, we globally evaluated the relative contributions of each feature across four sets of relatively effective algorithms. This comprehensive analysis enhances our understanding of the adsorption mechanism of magnesium oxide on carbon dioxide and provides valuable insights to guide the design of the next generation of high-performance magnesium oxide materials for carbon capture and storage. [ABSTRACT FROM AUTHOR]