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The gantry crane, positioned atop the bridge pier cap for the installation of Super-T girders, is a specialized construction unit within the bridge construction industry. The article presents a summary of research results investigating dynamic parameters and their influence on the operation of gantry cranes with assembled structures on the cap of bridge piers, serving the installation of Super-T beams in two scenarios: lifting with pre-stressed cable and moving with load (Super-T beam). To examine the dynamic parameters affecting the operation of the gantry crane, the authors first constructed a dynamic model. Subsequently, the influential parameters were determined, and the Matlab Simulink software was employed to develop a survey model corresponding to different values of each parameter and under various working conditions of the gantry crane. This process aimed to identify patterns and unfavorable values of these parameters affecting the operation of the gantry crane. The research results revealed that in both scenarios of lifting with pre-stressed cable and moving with a load (loading), factors such as lifting speed (Vn), stiffness of the main steel structure (S3), conversion stiffness of the lifting cable (S1), oscillation mass of the main structure (m3), wind load acting on the beam (Pg2), wind load acting on the main steel structure (Pg1), and stiffness of the hanging cable (S1) significantly influence the operation of the gantry crane. The survey results also indicated reasonable values for these influential factors during the operation of the gantry crane. The obtained research results can serve as a basis for computational design problems and effective utilization of gantry cranes with assembled structures on the cap of bridge piers for the installation of Super-T beams. Through analysis and simulation using Matlab-Simulink software, specific data on cable tension, main structure acceleration, and structural deformation were collected. The results emphasize the importance of limiting the lifting speed to 2 m/min to ensure stability during cable tensioned lifting and restricting the crane's moving speed to 7.85 m/min to maintain safety and performance when moving loads with tensioned cables. [ABSTRACT FROM AUTHOR]

Summary In this article, we exploit the huge advantages of full‐duplex (FD) transmission, nonorthogonal multiple access (NOMA) technique, unmanned aerial vehicle (UAV), and millimeter‐wave (mmWave) communications in an Internet of things (IoT) sensor network. Specifically, the UAV operates as a FD amplify‐and‐forward (AF) relay to aid communications between an IoT sensor and multiple NOMA users. Moreover, the FD‐UAV (FDU) adopts both fixed and variable gains. We obtain exact expressions of outage probability (OP) and throughput of IoT‐FDU‐NOMA‐mmWave network with fixed and variable gains at FDU over Nakagami‐m$$ m $$ fading channels. Numerical illustrations clearly show that the OP and throughput performance of the IoT‐FDU‐NOMA‐mmWave network with variable gain are considerably higher than those with fixed gain. Since mmWave bands are used, the OP and throughput of the IoT‐FDU‐NOMA‐mmWave network are greatly affected by carrier frequency and communication distances. Consequently, when the carrier frequency or/and the distances between the IoT sensor and the users increase, the transmit power of the IoT sensor and the FDU should be increased to maintain the network performance. On the other hand, the effects of residual loop interference (LI) induced by FD transmission are remarkable. Thus, more efforts to reduce the residual LI power have to be continuously performed. Moreover, the specific impacts of the key parameters such as fading order m$$ m $$, the positions of the FDU, and data rates are clarified. More importantly, in practice, according to the fixed gain or the variable gain that is used, we can locate the position of FDU to achieve the best performance for the IoT‐FDU‐NOMA‐mmWave network. [ABSTRACT FROM AUTHOR]