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The hiding capacity (HC), imperceptibility, and security are the 3 important quality measures for a steganography technique. While the stego-image is on transit on the internet, the hidden data may be changed because of various reasons. The existing techniques does neither focus on detecting the errors in the data nor to correct the errors in data. Therefore, this article brings forward a steganography technique, wherein error detection and correction can be performed at recipient side. The original image is logically sliced into $2\times 2$ disjoint blocks. From these 4 pixels, 4 quotients and 4 least significant bits (LSBs) are generated. Each quotient is the decimal value of 7 most significant bits (MSBs) of a pixel. In every block 8 data bits can be camouflaged. From the 8 data bits, 4 redundant bits are computed using modified Hamming code. The 8 data bits and one redundant bit are camouflaged in the quotients by either quotient value differencing (QVD) or bit substitution. If camouflaging is performed in quotients using QVD, then indicator bit is set to1. Otherwise, if camouflaging in quotients is performed using bit substitution, then indicator bit is set to 0. The 3 remaining redundant bits along with the indicator bit are stored in the LSBs of the 4 pixels. At the receiver side, data could be extracted, and error correction procedure could be applied to correct 1-bit error over the 8 bits of data extracted from a block. From the experimental reports it could be concluded that the errors in the retrieved data at the recipient can be detected and corrected without reducing the HC and without increasing the distortion.

Microgrids are being evolved as a potential alternative to reduce unrelenting dependency on central utility grids. Moreover, integrated multi-microgrid based clusters are forming in closed vicinities to enhance the benefits of microgrids. However, the power quality problem is one of the key issues to be solved in such systems, which is mainly caused by the rising penetration of nonlinear loads and interfacing of power electronic converters. To address this issue, this paper proposes a new control technique, named “adaptive neuro-fuzzy control strategy”. This controls the inverter of each microgrid in the cluster as well as the voltage source converter-based distribution static compensator located at the point of common coupling between the cluster and the utility grid. This proposed control strategy uses the advantages of both fuzzy logic and artificial neural networks, thereby effectively controlling the system. The proposed technique is modelled in MATLAB/Simulink software 2021a. For the analysis, various power quality indices such as voltage sag/swell, voltage unbalance, frequency deviations, power characteristics, total harmonic distortion, and neutral current compensation are measured. These indices of the proposed controller are compared with conventional PI and fuzzy logic-based controllers in view of various key IEEE/IEC standard tolerances. From these results, the proposed controller has proved its superiority.

The energetic events on the sun, solar wind and subsequent effects on the Earth's geomagnetic field and upper atmosphere (ionosphere) comprise space weather. Modern navigation systems that use radio-wave signals, reflecting from or propagating through the ionosphere as a means of determining range or distance, are vulnerable to a variety of effects that can degrade the performance of the navigational systems. In particular, the Global Positioning System (GPS) that uses a constellation of earth orbiting satellites are affected due to the space weather phenomena. Studies made during two successive geomagnetic storms that occurred during the period from 8 to 12 November 2004, have clearly revealed the adverse affects on the GPS range delay as inferred from the Total Electron Content (TEC) measurements made from a chain of seven dual frequency GPS receivers installed in the Indian sector. Significant increases in TEC at the Equatorial Ionization anomaly crest region are observed, resulting in increased range delay during the periods of the storm activity. Further, the storm time rapid changes occurring in TEC resulted in a number of phase slips in the GPS signal compared to those on quiet days. These phase slips often result in the loss of lock of the GPS receivers, similar to those that occur during strong(>10 dB) L-band scintillation events, adversely affecting the GPS based navigation.

The present research aims to improve the convective thermal transport rate of a hybrid nanofluid within an inverted T‐shaped porous enclosure using strategically placed cold circular cylinders. Different locations of circular cylinders in the physical domain are distinguished with nomenclatures as Cases C0‐C4. The mathematical model, based on the Darcy–Brinkman–Forchheimer equation, is numerically simulated through the penalty finite element method. Fluid flow and heat transfer characteristics are depicted graphically, showcasing streamlines, isotherms, mean Nusselt number (Num$Nu_m$), and heat transfer enhancement percentage (En%) across varied thermo‐physical parameters, including Rayleigh number (Ra=103−106$Ra=10^3-10^6$), Darcy number (Da=10−5−10−2$Da=10^{-5}-10^{-2}$), and porosity values (ε=0.1−0.9$\epsilon =0.1-0.9$). Notably, the presence of two circular cylinders at the bottom flow zones (Case C4) demonstrates superior heat transfer compared to other spatial cylinder arrangements with increasing Ra$Ra$. Furthermore, augmenting flow parameters (Ra,Da,ε$Ra, Da, \epsilon$) in the case C4 model intensifies convective heat and fluid flow phenomena. A comparative analysis of thermal transport activity between Case C4 and the simple physical domain (Case C0) reveals maximum thermal enhancement of 166%, 167%, and 36% across varying Ra$Ra$, Da$Da$, and ε$\epsilon$ values. This comprehensive analysis suggests that two circular cylinders (Case C4) at the bottom flow section of the porous enclosure provide an effective strategy for enhancing convective fluid and thermal transport phenomena in an inverted T‐shaped porous enclosure. Moreover, this research significantly contributes in optimizing the thermal transport engineering of T‐shaped applications like solar collectors, exchangers, and heat storage. [ABSTRACT FROM AUTHOR]

This research aims to enhance convective thermal transport in an inverted T-shaped porous enclosure filled with a water-based hybrid nanofluid, incorporating a circular cylinder at different vertical locations (Case C1-no cylinder, Case C1-cylinder at (0.5, 0.25), Case C2-cylinder at (0.5, 0.5), Case C3-cylinder at (0.5, 0.75)). The numerical investigation employs the penalty finite element technique to simulate the Darcy–Brinkmann–Forchheimer-based mathematical model. Moreover, the complete results of streamlines, isotherms, mean Nusselt number (Num), and thermal enhancement percentage ( En % ) are analyzed at the broad range of flow parameters, including Rayleigh number ( Ra = ( 10 3 − 10 6 ) ), Darcy number ( Da = ( 10 − 5 − 10 − 2 ) ), and porosity value ( ϵ = (0.1 − 0.9) ). Initial comparative investigations of different configurations (C0–C3) at selected Ra values reveal that case C1 exhibits significant potential for enhancing convective heat transport phenomena. Consequently, only case C1 physical domain has been explicitly analyzed for convective heat and fluid flow characteristics at the selected range of flow parameters. Further, it is analyzed that the increasing range of Ra, Da, and ϵ enhances the convective heat and fluid flow phenomena. Furthermore, the comparative study of Num and En % for case C1 against the simple case C0 reveals substantial improvements as Ra, Da, and ϵ increase. The En % for Da and Ra reaches up to 97%, while a maximum of 25% improvement is observed with varying values of ϵ. These findings highlight the promising opportunities to optimize convective thermal transport in the investigated system, mainly through adopting case C1. [ABSTRACT FROM AUTHOR]

Metaverse has garnered considerable attention in recent times. Given its swift pace of development, it is imperative to study the adoption of the metaverse. This study analyses the perceptions and drivers influencing the behavioural intention to use the metaverse among Generation Z and millennials by employing a sequential mixed‐methods approach. In the first stage of the study, in‐depth expert interviews were conducted (n = 20), and the subsequent stage featured a countrywide survey (n = 1253). The outcomes of this study indicate that perceived usefulness, personal innovativeness, perceived enjoyment, facilitating conditions, telepresence, social presence, trust, and regulatory support influence attitudes and behavioural intentions towards the metaverse. The findings also reveal a significant difference in the strength of a few relationships across age, gender, and income levels, shedding light on the crucial factors for organisations seeking to position themselves strategically among various demographic groups. This study significantly contributes to the existing knowledge on emerging optimistic and pessimistic perceptions and factors affecting the adoption of the metaverse. By harnessing these outcomes, organisations can enhance the development and promotion of metaverse experiences. [ABSTRACT FROM AUTHOR]