In this work, a comprehensive technology computer aided design-based investigation of a buffer-free high electron mobility transistor under proton radiation is presented. With a 37.55% thinner architecture (without thick and highly doped Fe buffer) grown on silicon carbide substrate, this device design improves the two-dimensional electron gas (2DEG) confinement and helps to eliminate the various dispersion effects and buffer leakage. To gain better insight into the buffer-free device architecture, direct current (DC), thermal, and radio frequency (RF) studies are carried out. To establish the various prospects of this device in high-power and space applications, the performance of the device under 1.8 MeV proton radiation environment is systematically studied. A comparison demonstrates that the buffer-free structure under proton radiation with fluence 1 × 10 14 c m − 2 shows a current I D , M a x degradation of 18.68% compared with 72.7% in the case of conventional architecture. The excellent capability of the buffer-free device to confine 2DEG more precisely even under radiation environments can be concluded from the various DC and RF parameters studied. An extensive study of the effects of proton fluences and biases on the RF power amplifier figures of merit was also conducted by carrying out harmonic balance simulations for different radiation setups, which demonstrates excellent performance of the buffer-free structure.

With the advent of technology and multimedia production, the world has witnessed a tremendous increase in digital media attacks, which duplicates, forges and tamper the data leading to the violation of copyright laws. In this paper, a robust and secure digital image watermarking is proposed, which exploits the chaotic behaviour of the nonlinear oscillators realized through Memristive diodes. The proposed scheme relies on a Human Visual System (HVS) model in order to mimic the real-life scenario. To improve the robustness of the proposed approach and to further increase the security of the digital watermarked media whilst still retaining compatibility with the real-time events, Histogram of Oriented Gradients (HOG) and extreme learning machine (ELM) is implemented. Secure key generation by means of scrambling through Arnold Transform and the coefficients of Memristive Chaotic Oscillator ensures extreme security. The watermark embedding followed the pixel transformation based on discrete cosine coefficient modification, and a semiblind watermarking extraction procedure was carried out through trained ELM models. A detailed analysis has been presented to evaluate the tradeoff between imperceptibility, security and robustness using performance metrics like PSNR, NC, SSIM, and BER. To establish a real-time implementation of the proposed architecture, the simulated results were verified using real-time chaotic signals generated from the chaotic oscillator, which dictates excellent performance against watermarking attacks and image processing tasks.

A hydrophobic and superoleophilic adsorbent was prepared by coating candle soot (CS) on the surface of a recycled egg carton material (ECM). This waste material has been explored as a cost-effective adsorbent to remove oil and detergent from water. The surface of the material was coated with CS solution prepared by mixing soot with acetone and characterized by scanning electron microscopy and contact angle measurements. The rate of fall of contact angle for water and oil was evident of water rejection and oil absorption capability of the coated-waste material. Further, the effect of temperature on the contact angle between water and surface was observed. The carbon-coated ECM demonstrates good absorption capacity with oils of different densities, without pre-treatments and surface modifications. It also shows its capability to absorb detergent from water with a pH value declining towards 7. Thus, a waste material can act as an effective alternative for filtering of oil and detergent water for households and industries.

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