Analytical study of hardware-rooted security standards and their implementation techniques in mobile

Telecommunication Systems - Security of information in computers is of paramount importance. Considering the software security as inadequate, hardware rooted security standards were developed as...     

A novel relaxor (Bi,Na,Ba)(Ti,Zr)O3 lead-free ceramic with high energy storage performance

Energy storage ceramic capacitors advance in high power density and working voltage, but challenge in simultaneously large recoverable energy density (W_rec), high energy efficiency (η), and good thermal stability. To achieve this, a novel lead-free ceramic system (1-x)(Bi_0.5Na_0.5)TiO₃-x(BaZr_0.3Ti_0.7O₃) [(1-x)BNT-xBZT] was explored by tailoring the ferroelectric relaxor states. The introduction of BZT gradually promotes the transformation of ferroelectric states into relaxor states at around the room temperature for x = 0.3-0.5 that presents a pinched P-E loop. The optimized composition of x = 0.45 possesses a large W_rec of up to 2.6 J/cm³ and ultrahigh ƞ of 94%, with only a small variation (±8%) in W_rec and the high ƞ (90%) over a broad temperature range (−30°C to 180°C), demonstrating the superior performances compared to many existing lead-free ceramics. The remarkable advantages of the novel BNT-BZT lead-free ceramics explored in this study are thus promising for the high-efficiency and temperature-stable energy storage capacitor applications.     

Deposition of bismuth sulfide and aluminum doped bismuth sulfide thin films for photovoltaic applications

Journal of Materials Science: Materials in Electronics - Binary bismuth sulfide (Bi2S3) and ternary aluminum-doped bismuth sulfide (Al@Bi2S3) thin films were prepared by the chemical bath...     

Cogent and Energy Efficient Authentication Protocol for WSN in IoT

Given the accelerating development of Internet of things (IoT), a secure and robust authentication mechanism is urgently required as a critical architectural component. The IoT has improved the quality of everyday life for numerous people in many ways. Owing to the predominantly wireless nature of the IoT, connected devices are more vulnerable to security threats compared to wired networks. User authentication is thus of utmost importance in terms of security on the IoT. Several authentication protocols have been proposed in recent years, but most prior schemes do not provide sufficient security for these wireless networks. To overcome the limitations of previous schemes, we propose an efficient and lightweight authentication scheme called the Cogent Biometric-Based Authentication Scheme (COBBAS). The proposed scheme is based on biometric data, and uses lightweight operations to enhance the efficiency of the network in terms of time, storage, and battery consumption. A formal security analysis of COBBAS using Burrows–Abadi–Needham logic proves that the proposed protocol provides secure mutual authentication. Formal security verification using the Automated Validation of Internet Security Protocols and Applications tool shows that the proposed protocol is safe against man-in-the-middle and replay attacks. Informal security analysis further shows that COBBAS protects wireless sensor networks against several security attacks such as password guessing, impersonation, stolen verifier attacks, denial-of-service attacks, and errors in biometric recognition. This protocol also provides user anonymity, confidentiality, integrity, and biometric recovery in acceptable time with reasonable computational cost.     

High-Field Magneto-Conductivity Analysis of Bi<Subscript>2</Subscript>Se<Subscript>3</Subscript> Single Crystal

We report the high-field (up to 14 Tesla) magneto-conductivity analysis of Bi₂Se₃ topological insulator grown via the self-flux method. The detailed experimental investigations including crystal growth as well as the electrical, thermal, and spectroscopic characterizations of the resultant Bi₂Se₃ single crystal are already reported by some of us. The current letter deals with high-field magneto-conductivity analysis in terms of Hikami Larkin Nagaoka (HLN) model, which revealed that the electronic conduction is dominated by both surface state-driven weak anti-localization (WAL), as well as the bulk weak localization (WL) states. Further, by applying the HLN equation, we have extracted the fitting parameters, i.e., phase coherence length (l_φ) and the pre-factor (α). Here, the magneto-conductivity data is fitted up to ± 5 Tesla, but in order to extract reliable fitting parameters, the same is fitted at much lower magnetic fields, i.e., up to ± 1 Tesla. The value of the HLN coefficient (α), extracted from the HLN equation exhibited values close to ? 1.0, indicating both WAL and WL contributions. On the other hand, the extracted \(l_{\varphi }\) is seen to decrease from 11.125 to 5.576 nm as the temperature is increased from 5 to 200 K, respectively. Summarily, the short letter discusses primarily the temperature-dependent magneto-conductivity analysis of pristine Bi₂Se₃ single crystal by the HLN model.     

Influence of PVP/PEG impregnated CuO NPs on physiological and biochemical characteristics of Trigonella foenum‐graecum L

Incorporation of nanoparticles into a number of manufacturing products raised the concern of environmental release via deliberate or accidental routes. Here, experiments were performed to examine the effect of copper oxide nanoparticles (CuO NPs), and polyvinyl pyrrolidone (PVP) and polyethylene glycol (PEG) impregnated CuO NPs on seed germination and growth of Trigonella foenum‐graecum L. as well as on callus induction through tissue culture technique. Seed germination frequency, length, and weight parameters did not inhibit at higher extent by application of NPs; however, copper acetate, PVP, and PEG significantly decreased the values of all parameters. In all the cases, negative effects were observed concentration‐dependent. PVP and PEG impregnated CuO were found less toxic for calli fresh and dry weight induced from leaf and stem explants. The 2, 2‐diphenyl‐1‐picrylhydrazyl reagent‐free radical scavenging activity, total antioxidative potential, and total reducing power potential along with total flavonoid and phenolic contents are found elevated in root when compared with shoot. Furthermore, impregnation of PVP and PEG on CuO NPs increases the oxidative response. The results conclude that impregnation of organic molecules on nanoparticles does not reduce the toxicity though can be exploited for enhanced production of secondary metabolites for medicinal purposes.Inspec keywords: botany, copper compounds, nanoparticles, toxicology, polymers, biochemistry, nanomedicine, biological tissues, free radical reactionsOther keywords: PVP‐PEG, physiological characteristics, biochemical characteristics, Trigonella foenum‐graecum L, copper oxide nanoparticles, polyvinyl pyrrolidone, polyethylene glycol, callus induction, tissue culture technique, seed germination frequency, weight parameters, copper acetate, leaf explants, stem explants, 2,2‐diphenyl‐1‐picrylhydrazyl reagent‐free radical scavenging activity, antioxidative potential, reducing power potential, flavonoid, phenolic contents, root, shoot, oxidative response, organic molecules, toxicity, secondary metabolites, CuO     

An efficient adaptive EWMA control chart for monitoring the process mean

In recent years, the memory‐type control charts—exponentially weighted moving average (EWMA) and cumulative sum (CUSUM)—along with the adaptive and dual control‐charting structures have received considerable attention because of their excellent ability in providing an overall good detection over a range of mean‐shift sizes. These adaptive memory‐type control charts include the adaptive exponentially weighted moving average (AEWMA), dual CUSUM, and adaptive CUSUM charts. In this paper, we propose a new AEWMA chart for efficiently monitoring the process mean. The idea is to first design an unbiased estimator of the mean shift using the EWMA statistic and then adaptively update the smoothing constant of the EWMA chart. The run length profiles of the proposed AEWMA chart are computed using extensive Monte Carlo simulations. Based on a comprehensive comparative study, it turns out that the proposed AEWMA chart performs better than the existing AEWMA, adaptive CUSUM, dual CUSUM, and Shewhart‐CUSUM charts, in terms of offering more balanced protection against mean shifts of different sizes. An example is also used to explain the working of the existing and proposed control charts.     

Acrylic three‐dimensional networks. II. Behavior of different acrylic ion exchangers in the retention and elution processes of some metal cations

The retention process of the Cu(II) and Ni(II) cations from CuSO₄ and NiSO₄ aqueous solutions by eight acrylic ion exchangers was studied. Also, the elution process of these cations with 0.5 mol · L⁻¹ HCl solution was analyzed. The quantitative retention and elution as well as the development aspects of the two processes were observed by the column method. Seven ion exchangers contained weak base, weak acid, and amphoteric functional groups, these being known as chelating agents. Also, an ion exchanger with carboxylic groups, as a model, was taken in this study. The experiments show that the ion exchangers can be divided in three types as follows: (a) bad chelating agents; (b) chelating ion exchangers with the limited efficiency; (c) ion exchangers with good chelating properties and a high application efficiency; especially, the ion exchanger with hydroxamic functional groups is considered in this class. Also, the experimental data prove that, both for Cu(II) and Ni(II) cations, the volume of the purified effluent is higher than the HCl volume needs for their complete elution. This fact means concentration of the metal cations in the liquid phase. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1387–1394, 1999