Chaitanya Bharathi Institute of Technology

A finite element framework has been developed to explore the nonlinear dynamic instability exhibited by stiffened plates subjected to in-plane harmonic edge loading. In this framework, an eight-noded isoparametric degenerated shell element is used to model plate skin, while a three-noded curved beam element is employed to model the stiffener. The formulation of system matrices for both the plate skin and the stiffener is based on the Green-Lagrange strain displacement relationship, using the total Lagrangian approach. The Bolotin method is then applied to identify the region of linear dynamic instability. The Incremental Harmonic Balance (IHB) method is utilized to investigate the nonlinear frequency response of stiffened plates.

Increased load demand necessitates the strengthening of structural members to withstand the unanticipated loads during their service life. This study focuses on improving the axial performance of cold-formed steel (CFS) lipped angles under axial compression through strengthening, which otherwise are prone to local and global instabilities. Fiber-reinforced composites possess a high strength-weight ratio and, hence, are widely adopted for structural strengthening. This research aims to assess the axial performance of CFS lipped angle (equal-leg) columns strengthened with carbon fiber reinforced polymer (CFRP). The influence of uni-directional (UD) CFRP on the axial capacity of 0.5 m length lipped angle, considering both 0° (CF_UD-0°) and 90° (CF_UD-90°) strengthening configurations was investigated. The findings demonstrate that CF_UD-0° resulted in 31

Equatorial plasma bubbles (EPBs) are ionospheric irregularities that degrade Global Navigation Satellite System (GNSS) signal quality through rapid total electron content (TEC) fluctuations and scintillation. This study presents a novel approach for EPB detection with Doppler Index and classification using an Xtreme Gradient Boosting (XGBoost) model based on multi-feature GNSS parameters. Doppler index (DI), vertical TEC (VTEC), elevation angle, timestamp and Ionospheric Pierce Point (IPP) were extracted from GNSS observations at the low-latitude IGS GNSS station HYDE during 12 geomagnetically active days spread across 2022, 2023 and 2025. Class imbalance was addressed using SMOTE and SMOTE-Edited Nearest Neighbors (SMOTEENN). To test the robustness, EPB events over the years 2015, 2023, 2024 and 2025 were considered, excluding the days from the train dataset. Results indicate that XGBoost with SMOTEENN has an accuracy of 96.67

Integrating cutting-edge technology with conventional farming practices has been dubbed “smart agriculture” or “the agricultural internet of things.” Agriculture 4.0, made possible by the merging of Industry 4.0 and Intelligent Agriculture, is the next generation after industrial farming. Agriculture 4.0 introduces several additional risks, but thousands of IoT devices are left vulnerable after deployment. Security investigators are working in this area to ensure the safety of the agricultural apparatus, which may launch several DDoS attacks to render a service inaccessible and then insert bogus data to convince us that the agricultural apparatus is secure when, in fact, it has been stolen. In this paper, we provide an IDS for DDoS attacks that is built on one-dimensional convolutional neural networks (IDSNet). We employed prairie dog optimization (PDO) to fine-tune the IDSNet training settings. The proposed model's efficiency is compared to those already in use using two newly published real-world traffic datasets, CIC-DDoS attacks.

The knowledge on thermodynamic irreversibility becomes indispensable in order to choose best design parameters of any thermal system. The main aim of this work is to assess thermal and hydrodynamic performance, and entropy generation analysis of a heat exchanger partially filled with aluminium metal foam. For the investigation, three different porous layer thicknesses (t) of 40, 60 and 80 mm varied from the wall side of the tube are considered. Four different pore densities of 10, 20, 30 and 45 PPI foam samples and their porosities ranging 0.90-0.95 are employed for the examination. The air flow Reynolds (Re) number is varied from 4500 to 20500. Local thermal non-equilibrium (LTNE) and Darcy-extended Forchheimer (DEF) flow models are employed in porous filled region of the heat exchanger. In the clear (non-metal foam) region of the heat exchanger, two-equations standard k-omega turbulence model is employed. Heat transfer enhancement ratio, performance evaluation criteria, 2nd law efficiency (eta 2nd) are discussed with respect to PPI and thickness of the foam sample. Additionally, total irreversibility associated with heat transfer and fluid friction increases with increasing flow Re number and found to be minimum for lower values of pore density of 30 PPI foam sample with porous layer thickness, t = 40 mm. The friction factor ratio (FFR) reduces marginally with increasing flow Re number and increases with increasing porous layer thicknesses of porous foams. Moreover, Bejan number (Be) reduces with increasing flow Re number and PPI's of metal foams. Further, for higher PPI with maximum porous layer thickness, the maximum entropy generation number (Ns) suggests that the process is more irreversible and as a result, a greater amount of energy becomes unavailable.