We present the timing analysis results of MAXI J1803\(-\)298, a black hole candidate, during its 2021 outburst using data obtained from the \textit{Insight-}HXMT and \textit{NICER} telescopes. Our ...analysis reveals that the source undergoes a state transition from the low/hard state to the hard intermediate state, followed by the soft intermediate state, and ultimately reaching the high/soft state. We searched for the quasi-periodic oscillations (QPOs) and studied the characteristics of the outburst. At the beginning of the outburst, the source was in the hard state, many type-C QPOs were seen in the \textit{Insight-}HXMT data, and the frequency of these QPOs increased from \(\sim 0.16\) to \(2.6\) Hz. Our analysis of the type-C QPOs' rms-frequency relationship indicates a turning point in the frequency. We also analyzed the phase lag versus frequency and energy relationship and deduced that the source likely has a high inclination angle, consistent with previous research. The observed rms and phase lag features in type-C QPOs could be explained by the Lense-Thirring precession model, while the alternatives would be still viable. The lag spectrum of type-B QPO exhibits a "\textit{U-shaped}" pattern similar to many other sources, and the type-B QPOs' rms increase as the energy rises. This phenomenon can be explained by the dual-corona model.
The increasing span of cable-stayed bridges has focused more attention on the aerostatic stability of the design and construction of such bridges. This paper presents a new method to analyze the ...nonlinear aerostatic stability of cable-stayed bridges including all three components of the wind load and the geometric nonlinearity. The analysis was used to investigate the effects of the wind angle of incidence, the wind load of individual bridge elements, the sagging of cable elements, the changes of tower height and the changes of side span length on the aerostatic stability of cable-stayed bridges. The results show that the wind angle of incidence and the wind loads on the cables have an important effect on the aerostatic stability of cable-stayed bridges.
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