Incentive based scheme for improving data availability in vehicular ad-hoc networks

Vehicular networks are popular in recent years to provide low cost communication medium during mobility. Vehicular Delay Tolerant Networks (DTNs) are one of the major categories of emerging technology. DTNs work on carry and forward mechanism to deliver data to the destination. The network performance gets severely affected due to reluctance shown by selfish nodes where few nodes show no interest in forwarding others data due to lack of any personal profit. The proposed mechanism is based on coalition game theory and discusses about incentive based mechanism which provides incentive to nodes which are forwarding data to forward to destination and motivates other vehicles in the network to participate in coalition to forward data. This scheme not only encourages other selfish nodes to forward their private data and other nodes’ public data as early as possible to destination but also increases reliability in the network as more nodes show their interest in selected routing protocol. The proposed scheme outperforms in overall benefit earned by individual node and whole coalition, and increases mutual cooperation which improves availability of data in the network.     

An Improved Histogram-Shifting-Imitated reversible data hiding based on HVS characteristics

In this paper, we propose a reversible data hiding scheme to hide a secret message into a cover image by considering the characteristics of Human Visual System (HVS) in order to improve the visual imperceptibility. The human eyes are more sensitive to the changes in the low intensity pixels than the higher intensity ones. Therefore, we divide the intensity levels (0–255) into four groups: the first group contains 0–79 intensity level; second, third, and fourth group contain, respectively, 80–151, 152–215, and 216–255 intensity levels. We further divide first group into segments of size 2 elements, second, third, and fourth group into 3, 4, and 5 elements sized segments, respectively. After constructing the segments, we scan the image in raster order to identify the peak points for each segment, which are used to embed the secret data. The secret data is also divided into the four segments according to the identified peak points per group. The first segment data is converted into base2 representation, second, third and fourth segment secret data into 3, 4, and 5 base representation, respectively. The first segment of secret data is embedded into the peak points belonging to first group, second, third and fourth group secret data is embedded into the peak points of second, third and fourth group, respectively. Thus, our scheme makes least changes into the pixels belonging to the first group which have least intensity values and most to the fourth group pixels which have highest intensity values. Experimentally, our scheme provides better quality stego image and hides more secret data than the other state of the art schemes. We also build a location map for all the peak points to ensure the reversibility of the proposed scheme.     

Preparation and charge transport studies of chemically synthesized polyaniline

Polyaniline doped with p-toluenesulfonic acid was synthesized using in situ chemical oxidation method for optimization of synthesis parameters. For p-toluenesulfonic acid/aniline molar ratio of 5, the obtained polymer exhibits highest value of the electrical conductivity. The electrical conductivity of polyaniline doped with p-toluenesulfonic acid was measured in the temperature range of 30–300 K. The conductivity of polyaniline was found to increase with rise in the temperature. The measured conductivity versus temperature data was fitted with Arrhenius model, variable range hopping (VRH) model and Kivelson model in order to investigate the charge transfer mechanism in polyaniline. It is shown that conductivity observed over wide temperature range of 30–300 K follows Kivelson model obeying power law behavior.     

Torsional deformation behavior of cracked gold nano-wires

The presence of in-homogeneity or defects in materials cannot be ignored. There is great need to understand the influence of defects on the mechanical response of nano-materials. In this study, atomistic simulations have been used to investigate the mechanical response of gold nano-wires under twisting. Simulations show that nano-wires have different elastic properties when defects are present. Embedded cracks of different sizes have been created in nano-wires to quantify in-homogeneity. The inter-atomic interactions are represented by employing an embedded-atom potential. The effect of different sizes of crack on potential energy, torque and stresses for investigating the mechanical response of a nano-wire is part of the whole investigation. It is predicted from our simulation that the presence of a crack and dimensions of the crack control the torsional response of gold nano-wires. Deviation in the behavior of gold nano-wires from continuum expectations is also discussed. The comparison of results of atomistic simulations is made with a linear elasticity model (of healthy and cracked nano-wires) to get deep insights into the nano-scale behavior of nano-wires.     

Effect of high or low molecular weight of components of feed on transmembrane flux during forward osmosis

The possible mechanism of water transport from feed to osmotic agent side during forward osmosis in situation when feed contains high or low molecular weight compounds and their combination has been presented. The orientation of membrane was found to influence the transmembrane flux. When the feed contains mixture of low and high molecular weight compounds mode I (feed towards the support layer) was found to result in lower flux values as compared to Mode II (feed towards active layer) due to significant external concentration polarization. Forward osmosis resulted in the concentration of betalains content in beetroot juice and anthocyanin content in grape juice from 50.92 mg/L to 2.91 g/L (57.1 fold) and from 104.85 mg/L to 715.6 mg/L (6.8 fold), respectively. Total soluble solids in case of beetroot, grape and pineapple juice were found to increase from 2.3 to 52 °Brix, from 8.0 to 54.6 °Brix from 4.4 to 54 °Brix, respectively.     

Impedance spectroscopy and dielectric properties of Ce and La substituted Pb0.7Sr0.3(Fe0.012Ti0.988)O3 nanoparticles

We present the structural, microstructural, dielectric and impedance behavior of Pb_0.7Sr_0.3[(Fe_2/3Ce_1/3)_0.012Ti_0.988]O₃ (PSFCT) and Pb_0.7Sr_0.3[(Fe_2/3La_1/3)_0.012Ti_0.988]O₃ (PSFLT) nanoparticles. These nanoparticles were prepared by a chemical synthesis route using polyvinyl alcohol as surfactant. The X-ray diffraction pattern shows polycrystalline nature with coexistence of tetragonal and cubic phase in both PSFCT and PSFLT nanoparticles. The average particle size has been measured using Scherer's relation. The average particle sizes also measured by TEM are 10 and 11 nm, and by SEM 9 and 12 nm, respectively, of PSFCT and PSFLT nanoparticles. By measuring the value of relative permittivity (?′) and loss (tan δ) at lower frequency, the dielectric properties show Maxwell-Wagner type interfacial polarization. However, due to nano size effect of PSFCT and PSFLT, dispersionless dielectric response has been observed up to higher frequency of 15 MHz. The frequency dependent real (Z′) and imaginary (Z″) parts of impedance confirmed the variation which was observed in dielectric properties. The values of resistance of grain boundaries, R_gb is higher than grains, R_g indicates that the effect of grain boundaries is dominant on electrical properties when the size of nanoparticles is quite small.     

Amelioration of nutritional properties of bakery fat using omega-3 fatty acid-rich edible oils: a review

Bakery products have gained prominence in modern diets due to their convenience and accessibility, often serving as staple meals across diverse regions. However, the fats used in these products are rich in saturated fatty acids and often comprise trans fatty acids, which are considered as a major biomarker for non-communicable diseases like cardiovascular disorders, obesity and diabetes. Additionally, these fats lack the essential omega-3 fatty acids, which are widely known for their therapeutic benefits. They play a major role in lowering the risk of cardiovascular diseases, cancer and diabetes. Thus, there is need for incorporating these essential fatty acids into bakery fats. Nevertheless, fortifying food products with polyunsaturated fatty acids (PUFAs) poses several challenges due to their high susceptibility to oxidation. This oxidative deterioration leads to not only the formation of undesirable flavors, but also a loss of nutritional value in the final products. This review focuses on the development of healthier trans-fat-free bakery fat enriched with omega-3 fatty acids and its effect on the physicochemical, functional, sensory and nutritional properties of bakery fats and products. Further, the role of various technologies like physical blending, enzymatic interesterification and encapsulation to improve the stability of PUFA-rich bakery fat is discussed, where microencapsulation emerged as a novel and effective technology to enhance the stability and shelf life. By preventing deteriorative changes, microencapsulation ensures that the nutritional, physicochemical and sensory properties of food products remain intact. Novel modification methods like interesterification and microencapsulation used for developing PUFA-rich bakery fats have a potential to address the health risks occurring due to consumption of bakery fat having higher amount of saturated and trans fatty acids. © 2023 Society of Chemical Industry.     

Magnetoelectric,Raman, and XPS Properties of Pb0.7Sr0.3[(Fe2/3Ce1/3)0.012Ti0.988]O3 and Pb0.7Sr0.3[(Fe2/3La1/3)0.012Ti0.988]O3 Nanoparticles

The Pb_0.7Sr_0.3[(Fe_2/3Ce_1/3)_0.012Ti_0.988]O₃ (PSFCT) and Pb_0.7Sr_0.3[(Fe_2/3La_1/3)_0.012Ti_0.988]O₃ nanoparticles were prepared by chemical synthesis route using polyvinyl alcohol as surfactant. X-ray diffraction pattern has been used to analyze the phase structure and average particles size. The phase structure is also confirmed by Raman spectra. The chemical states of Pb²⁺, Sr²⁺, Fe³⁺; Ti⁴⁺, Ce³⁺, La³⁺, and oxygen ions have been analyzed by X-ray photoelectron spectroscopy. The magnetoelectric coupling effect is confirmed by magnetic phase transition near ferroelectric phase-transition temperature. The magnetoelectric effect is also confirmed by measuring the value of magnetoelectric coefficient (α _E) as the function of applied dc magnetizing field under the influence of ac magnetic field of 10 Oe and frequencies of 847 and 997 Hz. The higher value of α _E is observed in PSFCT sample.     

Elasto-Thermodiffusive Surface Waves in a Semiconductor Half-Space Underlying a Fluid with Varying Temperature

The present article is aimed at an investigation of the propagation of elasto-thermodiffusive (ETN) surface waves in a homogenous isotropic, thermoelastic semiconductor material half-space underlying a viscous or inviscid fluid half-space or layer of finite thickness with varying temperature. The relaxation times of heat and charge carrier fields are also taken into consideration during the study. The secular equation that governs the propagation of elasto-thermodiffusive surface (interfacial) waves in the considered composite structures has been derived in compact form after obtaining the general wave solution of the model. Some particular forms of the general secular equation are also deduced and investigated. Numerical solution of secular equation and other relevant relations is carried out for silicon (Si) semiconductor material under different situations with the help of functional iteration numerical technique along with the irreducible case of Cardano's method. The computer-simulated results in respect of dispersion curves, attenuation coefficient, specific loss factor of energy dissipation and relative frequency shift due to loading are presented graphically to illustrate the analytical development. The results have been determined and compared with relevant publications available in the literature at appropriate stages of this work.     

A novel technique for generating desired vibrations in structure

A novel technique is presented for exciting desired transient vibrations in a structure. A cantilevered plate instrumented with piezoelectric sensor and actuator is used as a test-structure. Finite element model of the test-plate is developed using Hamilton's principle. Finite element model is reduced to first two modes using orthonormal modal truncation and then this reduced model is converted into a state-space model. Tracking optimal control is then employed to obtain desired transient curves simultaneously, of first two modes of vibration. Theoretical findings are verified by conducting experiments, for experimentation, Kalman observer is used to estimate first two modes and Labview software is used for interfacing. Presented strategy can be used to do dynamic vibration testing of a product by forcing the product to experience same transient vibrations that it is expected to experience in field.