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This paper introduces a numerical approach for the fractional-order Rössler chaotic systems and gives error analysis. The effectiveness of the present method is determined by comparing the numerical results of the high-precision difference scheme and predictor-correctors scheme. Some complex dynamical behaviors for the fractional-order Rössler chaotic systems are shown. [ABSTRACT FROM AUTHOR]

Stratospheric airships require a lightweight envelope to contain lighter-than-air buoyancy gas, making the lightweight design and pressure-bearing performance of the envelope structure a key research issue. The stress state at different cross-sectional positions of the airship envelope structure is different, resulting in a low utilization rate of the overall material performance of the envelope structure. This paper proposes a design scheme for reinforcing envelope structures with sliding reinforcing cable to improve the bearing capacity of the composite fabric structure while reducing its weight, ultimately achieving the optimal strength-to-weight ratio. Two types of composite fabric structures (A-airship and B-airship) were subjected to inflatable burst tests, and the strain changes in the envelope gores were analyzed by digital image correlation. Through re-assembly of the broken composite fabric pieces and analysis of their tear textures, crack origination positions, failure causes, and the stress behavior and state at the failure position were identified. An envelope structural model with consideration of the cutting pattern effect was established, allowing the stress distribution of the envelope to be analyzed and the damage positions to be more accurately predicted. Based on the analysis of the ultimate pressure-bearing performance of an airship envelope structure, a novel idea of incorporating coupled tensile-shear stress into the strength criterion was proposed. Through the data in the study and existing references, it is verified that the strength criterion can accurately predict the ultimate pressure-bearing performance of the envelope structure. [ABSTRACT FROM AUTHOR]

This paper proposes an assembled X-shaped flexural steel damper. Welding is waived for the novel damper. As the kernel element of the damper, the X-shaped flexural steel plates have the advantages of ease of installation and replacement if necessary. In the analytical part, the effective height of the flexural steel plate was suggested, and then, the yield displacement, yield load and initial stiffness of the damper were derived. The proof-of-concept cyclic loading test was conducted using one reduced-scale specimen within a four-bar linkage experimental setup. The hysteretic performance indexes, including strength, stiffness and energy dissipation, were quantified. The high-fidelity finite element (FE) models were established by ABAQUS. The parametric study was further conducted based on the verified FE model. The considered parameters were the height and thickness of the steel plates. The testing results indicate that the proposed damper has plump hysteretic curve with good energy dissipation capacity and excellent ductility, although slight slip behavior can be found due to the gap caused by the assembling process. The results obtained from analytical method and numerical model are in good agreement with the experimental data. The results of parametric analysis show that the numerical results well agree with analytical predictions, indicating the numerical model can reflect the mechanical behavior of AXSFD. A benchmark frame building was selected to demonstrate the seismic control efficacy of the damper. The nonlinear time history analysis results indicate that the damper reduced both peak and residual interstory drift ratios for the protected structure. [ABSTRACT FROM AUTHOR]