Random forest classifier‐based safe and reliable routing for opportunistic IoT networks

Designing a safe and reliable way for communicating the messages among the devices and humans forming the Opportunistic Internet of Things network (OppIoT) has been a challenge since the broadcast mode of message sharing is used. To contribute toward addressing such challenge, this paper proposes a Random Forest Classifier (RFC)‐based safe and reliable routing protocol for OppIoT (called RFCSec) which ensures space efficiency, hash‐based message integrity, and high packet delivery, simultaneously protecting the network against safety threats viz. packet collusion, hypernova, supernova, and wormhole attacks. The proposed RFCSec scheme is composed of two phases. In the first one, the RFC is trained on real data trace, and based on the output of this training, the second phase consists in classifying the encountered nodes of a given node as belonging to one of the output classes of nodes based on their past behavior in the network. This helps in proactively isolating the malicious nodes from participating in the routing process and encourages the participation of the ones with good message forwarding behavior, low packet dropping rate, high buffer availability, and a higher probability of delivering the messages in the past. Simulation results using the ONE simulator show that the proposed RFCSec secure routing scheme is superior to the MLProph, RLProph, and CAML routing protocols, chosen as benchmarks, in terms of legitimate packet delivery, probability of message delivery, count of dropped messages, and latency in packet delivery. The out‐of‐bag error obtained is also minimal     

High Frequency Electronically Tunable Floating Memristor Emulators employing VDGA and Grounded Capacitor

This paper introduces novel electronically tunable floating and grounded memristor emulator circuits using voltage differencing gain amplifier and one capacitor. The decremental and incremental memristor emulators have been suggested for both floating as well as grounded type configurations. Decremental to incremental and incremental to decremental configurations of memristor emulators can be easily obtained. The fingerprint of memristor is the pinched hysteresis loops that are maintained for the significant range of frequencies from 5 kHz to 1 MHz. The proposed memristor emulator sustains its range of frequency for both grounded and floating configurations. The simulations have been done in Eldo simulation tool of Mentor Graphics using TSMC 0.18 µm complementary metal-oxide semiconductor (CMOS) technology parameters. The proposed electronically tunable memristor emulators are used to realize analog filters in view of performance verification.

     

Dynamic attribute based vehicle authentication

Modern vehicles are proficient in establishing a spontaneous connection over a wireless radio channel, synchronizing actions and information. Security infrastructure is most important in such a sensitive scope of vehicle communication for coordinating actions and avoiding accidents on the road. One of the first security issues that need to be established is authentication via IEEE 1609.2 security infrastructure. According to our preliminary work, vehicle owners are bound to preprocess a certificate from the certificate authority. The certificate carries vehicle static attributes (e.g., licence number, brand and color) certified together with the vehicle public key in a monolithic manner. Nevertheless, a malicious vehicle might clone the static attributes to impersonate a specific vehicle. Therefore, in this paper we consider a resource expensive attack scenario involving multiple malicious vehicles with identical visual static attributes. Apparently, dynamic attributes (e.g., location and direction) can uniquely define a vehicle and can be utilized to resolve the true identity of the vehicle. However, unlike static attributes, dynamic attributes cannot be signed by a trusted authority beforehand. We propose an approach to verify the coupling between non-certified dynamic attributes and certified static attributes on an auxiliary communication channel, for example, a modulated laser beam. Furthermore, we illustrate that the proposed approach can be used to facilitate the usage of existing authentication protocols such as NAXOS, in the new scope of ad-hoc vehicle networks. We use BAN logic to verify the security claims of the protocol against the passive and active interception.     

Circular Fractal Antenna Design with Inscribed Square for Ultra Wide Band Applications

Journal of Communications Technology and Electronics - In this article, an ultra-wide band circular fractal antenna inscribed with square is presented. The prototype of the antenna is fabricated on...     

Evolution of magnetic and bone mineral phases in heat-treated bioactive glass containing zinc and iron oxides

Melt-quenched 15(ZnO,Fe₂O₃) 50SiO₂·20(CaO,P₂O₅) 15Na₂O bioactive glass was heat treated at temperatures (T_A) ranging from 550°C to 850°C for different time periods (t_A=1, 2 and 3 hours) to understand its devitrification characteristics. Crystallization of calcium sodium phosphate, zinc ferrite, magnetite, and hematite phases depended on heat treatment conditions. Decrease in saturation magnetizations (M_s) with increase in t_A of glass heat treated at T_A≥750°C is attributed to the formation of hematite which is a weak magnetic material. Magnetic properties as functions of T_A and t_A are interpreted on the basis of clustering of Fe ions, super-exchange interaction between Fe²⁺ and Fe³⁺ ions and formation of ferrimagnetic and weakly magnetic iron oxide phases with different heat treatment conditions. Electron paramagnetic resonance parameters reveal the variations in site distortions and randomness in Fe ion environment in the matrix upon heat treatment. In vitro mineralization ability of the glass-ceramics was evaluated by immersion in simulated body fluid (SBF) and monitoring both the pH variation of SBF and formation of hydroxyapatite surface layer as a function of immersion time. These studies help in assessing these glass-ceramics for hyperthermia treatment and in optimizing the processing conditions for this application.     

Reduced Maternal Erythrocyte Long Chain Polyunsaturated Fatty Acids Exist in Early Pregnancy in Preeclampsia

The present prospective study examines proportions of maternal erythrocyte fatty acids across gestation and their association with cord erythrocyte fatty acids in normotensive control (NC) and preeclamptic pregnancies. We hypothesize that maternal fatty acid status in early pregnancy influences fetal fatty acid stores in preeclampsia. 137 NC women and 58 women with preeclampsia were included in this study. Maternal blood was collected at 3 time points during pregnancy (16–20th weeks, 26–30th weeks and at delivery). Cord blood was collected at delivery. Fatty acids were analyzed using gas chromatography. The proportions of maternal erythrocyte α‐linolenic acid, docosahexaenoic acid, nervonic acid, and monounsaturated fatty acids (MUFA) (p < 0.05 for all) were lower while total n‐6 fatty acids were higher (p < 0.05) at 16–20th weeks of gestation in preeclampsia as compared with NC. Cord 18:3n‐3, 22:6n‐3, 24:1n‐9, MUFA, and total n‐3 fatty acids (p < 0.05 for all) were also lower in preeclampsia as compared with NC. A positive association was observed between maternal erythrocyte 22:6n‐3 and 24:1n‐9 at 16–20th weeks with the same fatty acids in cord erythrocytes (p < 0.05 for both) in preeclampsia. Our study for the first time indicates alteration in maternal erythrocyte fatty acids at 16th weeks of gestation which is further reflected in cord erythrocytes at delivery in preeclampsia.     

Studies on High Density Polyethylene in the Far-field Region in Ultrasonic Welding of Plastics

Polyethylene (PE) is an extremely versatile plastic and has the largest sales turnover than other plastics. With new uses for PE, researchers continue to find innovative technologies to process and join the material. Ultrasonic welding is one such process that is rapidly emerging as a major joining process for thermoplastics because of its reliability, ease of operation, fastness, and economic feasibility. Amorphous polymers are ideal materials for ultrasonic welding, but semicrystalline polymers are difficult to weld in the far-field region. This paper deals with the far field welding of semicrystalline polymer/high-density polyethylene (HDPE). The temperature distribution has been modeled for varying lengths of the specimen using Ansys to predict the temperature spikes, which can be related to the performance of the joints achieved. Experimental work studied the temperature at the joint interface and the variation in tensile strength for different lengths of the specimen.     

Geometrical Variability Impact on the Performance of Sub - 3 nm Gate-All-Around Stacked Nanosheet FET

Silicon - To meet the scaling targets and continue with Moore’s Law, the transition from FinFET to Gate-All-Around (GAA) nanosheet Field Effect Transistors (FETs) is the necessity for...     

Applicability of Field Plate in Double Channel GaN HEMT for Radio-Frequency and Power-Electronic Applications

Silicon - In the present communication, for the first time, applicability of Field Plate (FP) for Double Channel (DC) AlGaN/GaNHEMT is demonstrated. Impact of design space parameters such as field...     

Effects of acid leaching treatment of soda-lime silicate glass on crack initiation and fracture

Water or acid soaking surface treatments have been shown to increase the mechanical strength of soda-lime silicate (SLS) glasses. This increase in strength has traditionally been attributed to effects related to residual stress or changes in fracture resistance. In this work, we report experimental data that cannot be explained based on the existing knowledge of glass surface mechanics. In dry environments, annealed and acid-leached SLS surfaces have comparable crack initiation stress and fracture stress as measured by Hertzian indentation and biaxial bending tests, respectively. Yet, in the presence of humidity, acid-leached surfaces have higher failure stress than the annealed surfaces. This apparent enhancement in the crack resistance of the acid-leached surface of SLS glass in humid environments supports the hypothesis that acid-leached surface chemistry can lower the transport kinetics of molecular water to critical flaws.