Energy and Trust Management Framework for MANET using Clustering Algorithm

In General, Mobile Ad-Hoc Network (MANET) has limited energy resources, and it cannot recharge itself. This research goal focuses on building a power management scheme that saves energy in the MANET. Due to power instability, there is a chance that cluster heads fail and function incorrectly in cluster-based routing. As a result, instability occurs with the cluster heads while collecting data and communicating with others effectively. This work focuses on detecting the unstable cluster heads, which are replaced by other nodes implementing the envisaged self-configurable cluster mechanism. A self-configurable cluster mechanism with a k-means protocol approach is proposed to designate cluster heads effectively. The proposed k-means procedure is based on periodic irregular cluster head rotations or altering the number of clusters. We also propose a trust management mechanism in this research to detect and avoid MANET vulnerabilities. Because of the continuously changing topology and limited resources (power, bandwidth, computing), the trust management algorithm should only use local data. Consequently, compared to traditional protocols, the proposed approach with the k-means procedure and its experimental results show lower power usage and provide an optimal system for trust management.

     

Malayanines A and B, two novel limonoids from Chisocheton erythrocarpus Hiern

Two structurally interesting novel limonoids, malayanine A and malayanine B, were isolated from the bark of Chisocheton erythrocarpus Hiern. The structures were fully characterized through spectroscopic methods.     

Mechanochemical reaction of TiO<Subscript>2</Subscript> with β-alanine for the preparation of visible light active nitrogen doped titania: adsorption and kinetic studies

Nitrogen doped TiO₂ (TiO_2−xN_x) with a homogenous anatase phase was synthesized, using β-alanine as a nitrogen precursor and ethanol as a oxygen depriving agent in the concentration range of 0.05, 0.10, 0.15 and 0.2 at% and were characterized by Powder X-ray Diffraction (PXRD), X-ray Photoelectron Spectra (XPS), Scanning Electron Microscope (SEM), Fourier Transform Infrared (FT-IR) and UV–visible Diffused Reflectance Spectroscopic (DRS) techniques. Ethanol deprives the surface oxygen, thereby generating oxygen defects whose concentration was evaluated by FTIR, Photoluminescence (PL) and Electron Spin Resonance (ESR) studies. FTIR analysis reveal that concentration of oxygen vacancies/defects (V_o) decreases as the nitrogen concentration increases leading to the reduction in the Ti–O bond length. This results in a shift of the IR absorption peak towards a low wave number as predicted by simple physical harmonic oscillator model. The Ti 2p_3/2 XPS spectra of TiO_2−xN_x shifts to lower binding energies due to the increase in the electron densities around the Ti atoms indicating the formation of Ti³⁺ in the doped samples. N₂ adsorption–desorption isotherms measurements show a slight increase in the Brunner–Emmet–Teller (BET) surface area, pore diameter, mesopore volume, while the crystallite size and the morphology were also effected by the nitrogen doping. The equilibrium adsorption of Toluene molecules on the photocatalyst surface follows Langmuir theory and the rate controlling step could be the surface reaction of the adsorbed Toluene molecules.     

Solid-state halide ion-selective electrodes: studies of quaternary ammonium halide solutions and determination of surfactants

The feasibility of using homogeneous membrane-type halide ion-selective electrodes in solutions containing cationic surfactant compounds was examined. The results established the applicability of these electrodes for monitoring halide ions in solution without interference by the surfactants. The data also provided a basis for estimation of the surfactant in solution through the halide content. Two typical plating-bath compositions containing CTAB have been successfully analysed for their surfactant content by this procedure.     

Phenanthrene-imidazole-based fluorescent sensor for selective detection of Ag+ and F− ions: real sample application and live cell imaging

Research on Chemical Intermediates - 4-Methyl-2,6-bis(1H-phenanthro[9,10-d]imidazol-2-yl)phenol (probe-MPIP) conjugate has been designed as a selective fluorescent probe for silver (Ag+) ions. The...     

Malicious Node Detection in Wireless Sensor Networks Using an Efficient Secure Data Aggregation Protocol

Wireless sensor networks are randomly deployed and responsible for monitoring geographical area wide. In WSN, the aggregation of data is very complex because of its limited power and computing capabilities. Issue in data aggregation is that the data may be passed on malicious node. All the existing data aggregation techniques undergo security issues because of the transfer of large amount of data. In this paper we propose a protocol named Secure Data Aggregation Protocol (SDAP) which identifies the malicious node by providing a logical group in the form of tree topology. In the tree topology the aggregation is formed by aggregating the nodes, which are non-leaf node and high level of trust is required to provide a better approximation and accuracy against the security threats. Thus the data is securely aggregated and the efficiency is achieved in data aggregation.

     

OW‐SVM: Ontology and whale optimization‐based support vector machine for privacy‐preserved medical data classification in cloud

Cloud is a multitenant architecture that allows the cloud users to share the resources via servers and is used in various applications, including data classification. Data classification is a widely used data mining technique for big data analysis. It helps the learners to discover hidden data patterns by training massive data collected from the real world. Because this trained model is the private asset of an entity, it should be protected from all other noncollaborative entities. Therefore, it is essential to take effective measures to preserve the confidential data. The objective of this paper is to preserve the privacy of the confidential data in the cloud environment by introducing the medical data classification method. In view of that, this paper presents a method for medical data classification using a novel ontology and whale optimization‐based support vector machine (OW‐SVM) approach. Initially, privacy‐preserved data are developed adopting Kronecker product bat approach, and then, ontology is built for the feature selection process. Ontology and whale optimization‐based support vector machine is then proposed by integrating ontology and whale optimization algorithm into SVM, in which ontology and whale optimization algorithm is used for the feasible selection of kernel parameters. The experiment is done using 3 heart disease datasets, such as Cleveland, Switzerland, and Hungarian. In a comparative analysis, the performance of the OW‐SVM approach is compared with that of K‐nearest neighbor, Naive Bayes, decision tree, SVM, and OW‐SVM, using accuracy, sensitivity, specificity, and fitness, as the evaluation metrics. The OW‐SVM approach could achieve maximum performance with accuracy of 83.21%, the sensitivity of 91.49%, specificity of 73%, and fitness of 81.955, outperforming existing comparative techniques.     

Hexadecyltriethoxysilane-induced Dispersions of Metal Oxide Nanoparticles in Nonpolar Solvents

Nanoparticles of CeO₂, Fe₃O₄, TiO₂ and ZnO get coated by hexadecyltriethoxysilane on refluxing the nanoparticles and the organosilane in a hydrocarbon solvent. The organosilane-coated metal oxide nanoparticles give stable dispersions in hydrocarbon solvents due to their hydrophobic surface. On heating in air, the organosilane-coated metal oxide nanoparticles yield to silica-coated core-shell type nanoparticles. Dedicated to Late Professor F. A. Cotton.     

A simple urea-based route to ternary metal oxynitride nanoparticles

Ternary metal oxynitrides are generally prepared by heating the corresponding metal oxides with ammonia for long durations at high temperatures. In order to find a simple route that avoids use of gaseous ammonia, we have employed urea as the nitriding agent. In this method, ternary metal oxynitrides are obtained by heating the corresponding metal carbonates and transition metal oxides with excess urea. By this route, ternary metal oxynitrides of the formulae MTaO₂N (M=Ca, Sr or Ba), MNbO₂N (M=Sr or Ba), LaTiO₂N and SrMoO_3−xN_x have been prepared successfully. The oxynitrides so obtained were generally in the form of nanoparticles, and were characterized by various physical techniques.     

Structural characterization of Th-doped TiO2 photocatalyst and its extension of response to solar light for photocatalytic oxidation of oryzalin pesticide: a comparative study

The degradation efficiency of Th-doped TiO₂ / TiO₂ photocatalysts were investigated under UV and solar light illumination. The model compound chosen for the study was Oryzalin (OZ). Doping of inner transition metal ion Th was intended to modify the electronic properties of TiO₂. The Th-doped TiO₂ were synthesized by incorporating 0.02, 0.04, 0.06, and 0.1 atom percentage of Th into the TiO₂ lattice by solid-state reaction. The stochiometry of the prepared samples is Ti_1−xTh_xO₂, where ‘x’ is the percentage of Th. The samples were characterized by UV-Visible absorption, UV-Visible -Diffused reflectance spectra, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Analysis (EDX) and X-ray Diffraction (XRD). The pore size and surface area of these samples were studied by Brunauer, Emmett and Teller (BET) adsorption method. It was found that metal ion doping at various percentage compositions enables a large shift in the absorption band of the TiO₂ towards visible light region. This is due to the formation of various mid band gaps at 2.84 eV, 2.804 eV, 2.66 eV, and 2.55 eV. The extent of degradation of the pesticide was followed by UV-Visible spectroscopy and GC-MS methods. Based on the spectral analysis, the probable degradation reaction mechanism for OZ is proposed. These results indicate that Th-doped TiO₂ with the modified electronic properties is a good catalyst under solar light irradiation. But these particles show marginal variation in rates under UV-illumination. All the photodegradation reactions follow the first order kinetics.