The rapid development of the Internet of Medical Things (IoMT) has also facilitated real-time monitoring of healthcare, yet creates major issues of security, privacy, and interoperability, particularly in terms of emerging threats of quantum computing. This paper introduces a quantum-resilient blockchain paradigm, which combines post-quantum cryptography (PQC), ZeroKnowledge Proofs (ZKPs), and Fast Healthcare Interoperability Resources (FHIR) into secure and interoperable healthcare data management. Key encapsulation is performed using lattice-based algorithms, including Kyber and NTRU, and Dilithium and Falcon are algorithms used to secure digital signatures against quantum attacks. An authentication system which is based on a ZKP, and role-based access control allows privatizing access to electronic health records without exposing sensitive data. The framework is deployed on a PBFT-based permissioned blockchain and tested in simulated IoMT settings and has low latency, high throughput, and efficient cryptographic performance. In general, the suggested system will provide a reconfigurable, secure, and future-oriented method to safeguard the healthcare information against quantum threats without compromising the interoperability of the heterogeneous systems.
Solar energetic particles (SEPs) are major contributors to space weather conditions, especially protons with energies greater than 10 MeV, because they provide a critical scientific insight about the solar interplanetary processes. the relation between SEP flux and solar drivers (i.e., coronal mass ejections (CMEs) and solar flares) is discussed. For this, data collected between 1997-2024 were used; a total of 140 events were identified during this period, out of which around 75 % SEP events are linked with Halo CMEs. SC 23 has the most SEP events (87), followed by SC 24 (40) and SC 25 (13). Also, the study of the occurrence of SEP events with CME speed reveals that approximately 52 % SEP events were associated with fast CMEs (Speed>1400 km/s), 28 % with moderate CMEs (1000-1400 km/s), and approximately 20 % with slow-speed CMEs (Speed<1000 km/s). When the relationship between SEP events and CME-associated solar flares was investigated, it was found that more than 70 % of SEP-flare-related events originated from the western solar hemisphere, 30 % originated from the eastern hemisphere, and almost equal numbers of the SEP events are associated with northern and southern hemisphere-oriented solar flares. It was also found that approximately 50 % of SEP events are associated with Mclass solar flares, 29 % with X-class solar flares and only 21% with C-class solar flares. Finally, Regression and correlation analyses were conducted between the CME speeds and SEP Flux intensities, and separate fitted regression lines for each cycle indicate that they are in favour of the evident trend of a larger SEP flux with a faster CME speed and reflect a progressively stronger correlation. These findings illustrate that the CME dynamics and flare properties play a strong role in SEP production and propagation. For efficient space weather forecasting and satellite protection, it is important to monitor the real-time solar flare locations and CME parameters.
The shift to electric vehicles (EVs) has raised the requirements of high-efficiency, high power density on-board chargers (OBCs) with the capacity to comply with tough standards of power quality like IEC 61000-3-2. The paper provides a comparative study on the advanced Power Factor Correction (PFC) topologies that comprise Boost PFC, Multi-Phase Interleaved Boost PFC, Bridgeless Totem-Pole PFC, and Interleaved Totem-Pole PFC Converters. The input current shaping, voltage regulation, efficiency, switching stress, and general performance of various types of low-frequency (LF) switching devices; Metal Oxide Semiconductor Field Effect Transistor (MOSFETs), diodes and Silicon Controlled Rectifiers (SCRs) are systematically compared. A mathematical modeling framework and Average Current Mode Control (ACMC) strategy with nested proportional integral (PI) loops are developed and tested with an elaborate MATLAB/Simulink simulation. Both closed and open-loop performances are examined and proved that Totem-Pole PFC are more efficient as its power factor comes around 0.99, its THD is <5 %, efficiency >95 % and output voltage ripple comes less than 2 % with all low frequency devices and minimal with SCR around 2 % THD, 98 % efficiency and less than 1 % output voltage ripple. The findings give a viable design consideration to on-board chargers of high-performance EV.
Polycrystalline Ba1-xGdxTi0.965Sn0.035O3 (x = 0.00, 0.025, 0.05, 0.075) ceramics were synthesised via a solid-state route to investigate the effect of Gd3+ on the structural and microstructural properties of barium tin titanate (BTS). X-ray diffraction (XRD), supported by Rietveld refinement, confirmed a well-crystallised orthorhombic phase (Amm2) with systematic peak shifts indicating successful Gd incorporation. In contrast, a pyrochlore-type Gd2Ti2O7 secondary phase appeared at higher Gd contents (0.025 > x >= 0.05), marking the solubility limit. Williamson-Hall Plots showed that Gd doping reduces lattice strain while preserving long-range crystallinity. Electron-density contour and 3D Fourier maps revealed a periodically ordered lattice with subtle local rearrangements induced by Gd3+. FTIR spectra evidenced Ti-O vibrational modes alongside the disappearance of carbonate-related bands. The grain size, as calculated from FESEM micrographs, decreases from 0.721 & micro;m to 0.289 & micro;m due to the solute drag mechanism and the emergence of a secondary phase. Energy-dispersive spectroscopy confirms the elemental makeup of the synthesized samples. Raman spectroscopic analysis agrees well with the XRD studies. These structural and microstructural modifications establish a strong foundation for subsequent investigations into the enhanced dielectric and ferroelectric properties of Gd-modified BTS, highlighting its potential as a lead-free material for advanced capacitors, actuators, sensors, and energy-storage devices.
Phase transition and dielectric relaxation dynamics of a ferroelectric liquid crystal (FLC) material were investigated across the SmC*-N* phase transition using differential scanning calorimetry (DSC) and impedance spectroscopy under applied DC bias fields. Dielectric spectra recorded under DC bias exhibit anomalous low-frequency behavior in the vicinity of the SmC*-N* transition. A pronounced enhancement of low-frequency dielectric absorption is observed at low DC bias fields, followed by suppression at higher bias fields near similar to 72 degrees C, accompanied by the presence of the conventional Goldstone mode at slightly higher frequencies. The dielectric response over a wide temperature range, analyzed using a Cole-Cole-modified Debye model in both biased and unbiased conditions, reveals significant variations in the relaxation parameters. The low-frequency relaxation process close to the SmC*-N* transition is attributed to the combined contributions of the Goldstone mode and domain-related dynamics, as evidenced by the anomalous DC bias dependence of the dielectric parameters. The temperature dependance of relaxation parameters under DC bias exhibits conventional Goldstone-mode-like behavior due to suppressed domains and field-induced alignment of the spontaneous polarization.
