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The design of steel beam-column end-plate bolted connections is becoming increasingly popular owing to its simplicity of production. This requires knowledge of the full nonlinear resisting moment–rotation (M–Φ) behavior of the joint. To investigate the impact of various geometrical factors on the overall behavior of the connection, this work provides a three-dimensional finite element model (FEM) utilizing ABAQUS software. The suggested model accounts for the pretension force on the bolts, material and geometrical deviations from linearity, and the proximity of surfaces that are adjacent. The numerical model’s ability to simulate and process both the total and specific behavior of varieties of end-plate steel riveted connections is confirmed by calibrating the finite element findings with experimentally disclosed outcomes, which are reviewed in this study. The ultimate behavior was then investigated through a parametric study using the verified FEM with variations in the bolt pretension load, yield strength of the sections, and yield stress of the bolt considering the M–Φ curve. The results of the parametric study showed that as the bolt pretension load and yield stress of the column, beam, and plate materials increased, so did the connection’s moment ability. The yield tension of the bolts, however, had only a minor effect on the connection’s moment capacity.

Fault detection and isolation in unmanned aerial vehicle (UAV) propellers are critical for operational safety and efficiency. Most existing fault diagnosis techniques rely basically on traditional statistical-based methods that necessitate better approaches. This study explores the application of untraditional feature extraction methodologies, namely Permutation Entropy (PE), Lempel–Ziv Complexity (LZC), and Teager–Kaiser Energy Operator (TKEO), on the PADRE dataset, which encapsulates various rotor fault configurations. The extracted features were subjected to a Chi-Square (χ2) feature selection process to identify the most significant features for input into a Deep Neural Network. The Taguchi method was utilized to test the performance of the recorded features, correspondingly. Performance metrics, including Accuracy, F1-Score, Precision, and Recall, were employed to evaluate the model’s effectiveness before and after the feature selection. The achieved accuracy has increased by 0.9% when compared with results utilizing traditional statistical methods. Comparative analysis with prior research reveals that the proposed untraditional features surpass traditional methods in diagnosing UAV propeller faults. It resulted in improved performance metrics with Accuracy, F1-Score, Precision, and Recall reaching 99.6%, 99.5%, 99.5%, and 99.5%, respectively. The results suggest promising directions for future research in UAV maintenance and safety protocols. [ABSTRACT FROM AUTHOR]

The importance of the buried pipelines lies in two main topics: the first is related to the very long length of these pipes, and therefore protecting them is expensive. The second topic is related to environmental pollution due to leaching, which is considered one of the main pollutants of groundwater. The research reviews the effects of geosynthetic reinforcement and its effect on buried pipelines subjected to different loading conditions to reduce the stresses on them and thus prevent leakage. The loads covered in this literature are the following: static load, dynamic load, permanent ground deformation, accidental damage, uplift pressure, explosion, lateral loading, and abrasive shear loading. The research focused on the use of synthetic ground reinforcements to protect these pipes. Available experimental and numerical investigations indicate the potential of using geosynthetics to reduce the effects of external loads on buried pipelines. The investigated studies proved that the protection of buried pipes with different types of geosynthetics is a successful method and decreased the stresses transformed to buried pipes. Most of the studies (45%) dealt with buried pipes subjected to static loading. The conventional geosynthetic material used in the protection of buried pipes is geogrid (38%). [ABSTRACT FROM AUTHOR]