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Biometric de-identification is an emerging topic of research within the information security domain that integrates privacy considerations with biometric system development. A comprehensive overview of research in the context of authentication applications spanning physiological, behavioral, and social-behavioral biometric systems and their privacy considerations is discussed. Three categories of biometric de-identification are introduced, namely complete de-identification, auxiliary biometric preserving de-identification, and traditional biometric preserving de-identification. An overview of biometric de-identification in emerging domains such as sensor-based biometrics, social behavioral biometrics, psychological user profile identification, and aesthetic-based biometrics is presented. The article concludes with open questions and provides a rich avenue for subsequent explorations of biometric de-identification in the context of information privacy.

Y1-xDyxFeO3 (x = 0.0, 0.2, 0.4, 0.6 and 0.8) multiferroic materials are prepared by sol–gel method. The effect of Dy doping on the structural and magnetic properties of YFeO3 has been investigated in this paper. X-ray diffraction plots indicate that all the samples are crystalline and possess orthorhombic structure. The morphological studies show that samples possess non uniform grain size and grains are irregular in shape. Magnetic measurements suggest that substitution of Dy+3 ions in place of Y+3 ions effectively enhances the magnetization of YFeO3. This enhancement may be due to the additional Dy-Dy interactions, Dy-Fe interactions and Fe-O-Fe superexchange bond caused by the distortion of crystal structure.

A series of Gd1−xHoxMnO3 (x = 0, 0.1 and 0.2) compounds known to exhibit multiferroic properties has been investigated for their structural, magnetic and magnetocaloric properties. X-ray diffraction analysis confirms the presence of single orthorhombic phase at room temperature in all the compositions. Low temperature magnetocaloric properties of these compounds have been studied through specific heat measurements in the temperature range of 0–80 K under different magnetic fields of 0, 2 and 5 T. These studies also revealed the existence of Mn3+ ordering transition and lock-in transition (Tlock) near 40 K and 20 K, respectively. These compounds displayed antiferromagnetic (AFM) ordering of Gd3+ ions at low temperatures below 10 K. The magnetocaloric effect has been quantified in terms of the magnetic entropy change (ΔS)M and adiabatic temperature change (ΔT)ad in the vicinity of AFM transitions.

A water-immersible battery-powered field programmable gate array (FPGA)-based embedded system is a most suitable tool required to check the health of the pipe operating under harsh conditions. A novel, water-immersible, battery-powered, compact, stand-alone and FPGA-based embedded system has been designed and developed, which is suitable for ultrasonic pipe inspection and gauging systems useful for major applications in the petrochemical and nuclear industries. The developed FPGA-based embedded system is operated with lithium-ion batteries for more than five hours, and the IP67-grade system modules are capable of floating inside the pipe along with the flow of oil or water. Such applications require a system that is capable of acquiring large data under water-immersed conditions of battery-operated instrumentation. The onboard Double Data Rate (DDR) RAM of the FPGA module has been utilized for the storage of the 256 MBytes streams of A-scan data during evaluation for more than five hours. The experimentation of the battery-powered embedded system was carried out inside two samples of SS and MS pipes with the help of the in-house developed nylon inspection-head installed with two sets of spring-loaded eight Teflon balls and two 5 MHz focused immersion transducers placed along the circumference at 180° apart. This paper provides brief details of the design, development, and evaluation phases of the battery-powered water-immersible embedded system suitable for ultrasonic pipe inspection and gauging, which can be expanded to 256 channels for demanding applications.

Multiferroic materials with the compositional formulae Gd1-xHoxMn2O5 (x = 0, 0.1, 0.2, 0.3, and 0.4) were prepared by the conventional solid-state reaction method. The structural analysis has been carried out by X-ray diffraction technique which confirms the orthorhombic structure with the Pbam space group. The optical properties have been studied by UV Visible, FTIR, and Raman spectra. The energy gap that was calculated using UV visible absorption spectra shows that the material is semiconducting in nature. The observed 14 Raman and 17 IR active modes are attributed to the relative motions of corresponding atoms and by increasing the doping concentration of Ho, the emergence of phonon shifting was observed which suggests the possible multiferroic coupling behaviour. The electrical properties including dielectric constant, dielectric loss, and ac conductivity at room temperature indicate the spin-lattice coupling.

A water-immersible two-channel high-voltage (HV) spike pulser has been designed, developed, and mounted inside the IP 67 (Ingress Protection 67) grade enclosure, and it is suitable for the ultrasonic Pipe Inspection and Gauging (PIG) system utilized in the petrochemical industry. Such a critical and strategic application requires a portable, miniaturized, and water-immersible water-tight pulser module, which resides inside the pipe carrying water or liquid petrochemicals. The developed spike pulser printed circuit board (PCB) generates a HV negative spike pulse up to -300 V and 100 ns half-amplitude pulse width, required for the energization of ultrasonic immersion transducers of 5-10 MHz frequency. The water-immersible pulser is mounted inside the water-tight IP 67 grade enclosure, and it is operated through an external DC power supply/lithium batteries. The evaluation of the module was carried out using a two-channel water-immersible HV spike pulser, in-house developed preamplifier, and inspection head supported by four sets of spring-loaded Teflon balls for centering, and the inspection head carries two ultrasonic immersion transducers placed 180° apart and a sample SS pipe with a length of 400 mm, Inner Diameter of 200 mm, and Wall Thickness of 9 mm. The two-channel pulser module was evaluated in water to measure the dimensions of the sample SS pipe. This two-channel water-immersible novel spike pulser has dedicated circuitry, and each channel is a standalone PCB and it operates through external LV and HV DC supplies. The module can be scaled up to 256 channels for dimension measurement and flaw detection of long length pipes. In the absence of any literature available on the water-immersible pulser for PIG systems, the present two-channel pulser module has been designed and developed, and the module was evaluated by gauging of the SS pipe from inside. This paper provides the details of the water-immersible HV spike pulser module suitable for the gauging of metallic pipes.