Intrusion Detection System Against Colluding Misbehavior in MANETs

Routing protocol of MANET works with the presumption that nodes will transmit the data in collaboration. This presumption is a limitation of routing protocol which gives an occasion to attackers to hinder the security of the device and data in the network. Therefore, it becomes vital to develop methods and systems which will ensure the safety, integrity and confidentiality of data in such devices and systems. Although, existing IDS are able to detect various types of attack but some misbehavior goes undetected which potentially damage the network. Collusion attack is one such misbehavior where nodes perform maliciously in collaboration with neighboring nodes without being detected. In this work, Intrusion detection algorithm has been proposed that can effectively detect and isolate colluding nodes from the network so that these malicious nodes do not affect the performance of the network . Proposed detection algorithm uses in–out traffic information and overhearing statistics of nodes to identify colluding attackers. Detection algorithm works successfully for DSR routing protocol. Experimental results on NS-2 show that the proposed algorithm is capable of reducing the packet drops consequently improving the throughput of the network in presence of collusion attack.     

WO3 passivation layer-coated nanostructured TiO2: An efficient defect engineered photoelectrode for dye sensitized solar cell

Major loss factors for photo-generated electrons due to the presence of surface defects in titanium dioxide (TiO2) were controlled by RF-sputtered tungsten trioxide (WO3) passivation.X-ray photoelectron spectroscopy assured the coating of WO3 on the TiO2 nanoparticle layer by showing Ti 2p,W 4f and O 1 s characteristic peaks and were further confirmed by X-ray diffraction studies.The coating of WO3 on the TiO2 nanoparticle layer did not affect dye adsorption significantly.Dye sensitized solar cells (DSSCs) fabricated using WO3-coated TiO2 showed an enhancement of ～10％ compared to DSSCs fabricated using pristine TiO2-based photo-electrodes.It is attributed to the WO3 passivation on TiO2 that creates an energy barrier which favored photo-electron injection by tunneling but blocked reverse electron recombination pathways towards holes available in highest occupied molecular orbital of the dye molecules.It was further evidenced that there is an optimum thickness (duration of coating) of WO3 to improve the DSSC performance and longer duration of WO3 suppressed photo-electron injection from dye to TiO2 as inferred from the detrimental effect in short circuit current density values.RF-sputtering yields pinhole-free,highly uniform and conformal coating of WO3 onto any area of interest,which can be considered for an effective surface passivation for nanostructured photovoltaic devices.     

Dual degree branched type-2 fuzzy controller optimized with a hybrid algorithm for frequency regulation in a triple-area power system integrated with renewable sources

The uncertainties associated with multi-area power systems comprising both thermal and distributed renewable generation (DRG) sources such as solar and wind necessitate the use of an efcient load frequency control (LFC) technique. Therefore, a hybrid version of two metaheuristic algorithms (arithmetic optimization and African vulture’s optimization algorithm) is developed. It is called the ‘arithmetic optimized African vulture’s optimization algorithm (AOAVOA)’. This algorithm is used to tune a novel type-2 fuzzy-based proportional–derivative branched with dual degree-of-freedom proportional–integral–derivative controller for the LFC of a three-area hybrid deregulated power system. Thermal, electric vehicle (EV), and DRG sources (including a solar panel and a wind turbine system) are connected in area-1. Area-2 involves thermal and gas-generating units (GUs), while thermal and geothermal units are linked in area-3. Practical restrictions such as thermo-boiler dynamics, thermal-governor dead-band, and generation rate constraints are also considered. The proposed LFC method is compared to other controllers and optimizers to demonstrate its superiority in rejecting step and random load disturbances. By functioning as energy storage elements, EVs and DRG units can enhance dynamic responses during peak demand. As a result, the efect of the aforementioned units on dynamic reactions is also investigated. To validate its efectiveness, the closed-loop system is subjected to robust stability analysis and is compared to various existing control schemes from the literature. It is determined that the suggested AOAVOA improves ftness by 40.20% over the arithmetic optimizer (AO), while frequency regulation is improved by 4.55% over an AO-tuned type-2 fuzzy-based branched controller.     

High performance nanocomparator: a quantum dot cellular automata-based approach

Quantum dot cellular automata (QCA) are emerging nanotechnology that offers few significant advantages like faster speed, higher circuit density, and lower power dissipation. Comparator is a fundamental and essential block in QCA logic circuit family. In this article, a single-layered and straightforward design of a QCA-based one-bit magnitude comparator has been proposed. The proposed design is 6.38%, 6.67% and?~?10% more efficient in cell complexity, cell area and total area measurement, respectively, in comparison to prior reported designs. Furthermore, the energy dissipation of the proposed circuit has been calculated using QCADesigner-E and QCAPro tools to check the energy efficiency of the proposed circuit. The total energy dissipation of the reported magnitude comparator is 19.50 meV when measured using the QCADesigner-E tool. Similarly, according to the QCAPro tool, it has?~?71% less energy dissipation than the existing designs.

     

Memetic search in artificial bee colony algorithm

Artificial bee colony (ABC) optimization algorithm is relatively a simple and recent population based probabilistic approach for global optimization. ABC has been outperformed over some Nature Inspired Algorithms (NIAs) when tested over benchmark as well as real world optimization problems. The solution search equation of ABC is significantly influenced by a random quantity which helps in exploration at the cost of exploitation of the search space. In the solution search equation of ABC, there is a enough chance to skip the true solution due to large step size. In order to balance between diversity and convergence capability of the ABC, a new local search phase is integrated with the basic ABC to exploit the search space identified by the best individual in the swarm. In the proposed phase, ABC works as a local search algorithm in which, the step size that is required to update the best solution, is controlled by Golden Section Search approach. The proposed strategy is named as Memetic ABC (MeABC). In MeABC, new solutions are generated around the best solution and it helps to enhance the exploitation capability of ABC. MeABC is established as a modified ABC algorithm through experiments over 20 test problems of different complexities and 4 well known engineering optimization problems.     

Designing of biodegradable polycaprolactone: Binary and ternary coatings to minimize the defects and cost of solvent(s)

Coatings of polycaprolactone (PCL) in methylene chloride and toluene were prepared using solution casting method. Coatings of two different polymer mass percentages (5% and 10%), and thicknesses (800 and 1600 μm) were prepared. A drying study on PCL-methylene chloride-toluene coatings was carried out. The binary coatings of PCL-methylene chloride and PCL-toluene served as control cases. The results showed that the drying behavior was external mass transfer controlled for the binary coatings but diffusion controlled for the ternary coatings for most of the drying period. The drying rate enhanced but residual solvent increased with the progressive increase in initial concentration of methylene chloride and decrease in initial concentration of toluene. This shows that the drying rate can be enhanced by partially replacing the costly solvent with cheaper one, that is, toluene with methylene chloride. The coatings were characterized by scanning electron microscopy to understand the surface morphology. The scanning electron microscopy results further indicate that replacing toluene with methylene chloride caused disappearance of cracks, wrinkles, and phase-separation. The coatings with high initial content of methylene chloride were smooth and dense, and more residual solvent content does not manifest in coating defects. Hence, replacement of toluene with methylene chloride leads to savings on material and energy costs for drying along with better quality coatings.     

Methacrylic acid-co-butylmethacrylate copolymers: design,characterization and evaluation as encapsulating material for colon targeted formulations

Hydrophilic monomer methacrylic acid was copolymerized with hydrophobic monomer butylmethacrylate in different molar ratio, using AIBNfree radical initiator. Successful polymerization was confirmed by FTIR and ¹H NMR, while DSC and XRD revealed the amorphous nature of the polymers. Copolymers were highly hemocompatible. The polymers showed pH-dependent swelling and erosion which increased with increase in pH. As the amount of methacrylic acid increased, the swelling and erosion also increased. Polymers were used for the microencapsulation of a model anti-inflammatory drug, aceclofenac by an oil-in-oil solvent evaporation method. Microparticles were characterized using FTIR, XRD, DSC, and SEM analysis. The negatively charged particles were almost spherical in shape. The drug release was best explained by zero-order kinetics with anomalous release mechanism. Less than 1% of drug was released at pH 1.2 while the bulk of the drug load was released at pH 6.8 or above, confirming the colon-targeting nature. The microparticles showed significant lowering in myeloperoxidase activity in trinitrobenzene sulfonic acid-induced colitis rat model. There was a significant lowering in the severity of disease symptoms and colon-to-body weight ratio. The histopathological studies also confirmed successful treatment with microparticle formulation.     

Synthesis,phase confirmation and electrical properties of (1 − x)KNNS−xBNZSH lead-free ceramics

Journal of Materials Science: Materials in Electronics - In the present work, lead-free piezoelectric ceramics (Rx)(K0.5Na0.5)(Nb0.96Sb0.04O3)?x(Bi0.5Na0.5)(Zr0.8Sn0.1Hf0.1)O3 [abb. as...     

Strain-induced structural,magnetic and ferroelectric properties of heterostructure BST–NZFO nanocomposite thin film at room temperature

Heterostructure \(\hbox {Ba}_{0.7}\hbox {Sr}_{0.3}\hbox {TiO}_{3}\)–\(\hbox {Ni}_{0.8}\hbox {Zn}_{0.2}\hbox {Fe}_{2}\hbox {O}_{4}\) composite thin films grown on Pt–\(\hbox {TiO}_{2}\)–\(\hbox {SiO}_{2}\)–\(\hbox {Si}\) substrate were prepared by chemical solution process, where \(\hbox {Ba}_{0.7}\hbox {Sr}_{0.3}\hbox {TiO}_{3}\) layer grew as top/bottom while \(\hbox {Ni}_{0.8}\hbox {Zn}_{0.2}\hbox {Fe}_{2}\hbox {O}_{4}\) layer grew as bottom/top. Structural characterization by X-ray diffraction and atomic force microscopy showed the similar crystal structure, different lattice parameters, large lattice strain and small grain size in heterostructures, whatever their deposition sequences. Such heterostructures present simultaneously ferromagnetic and ferroelectric responses at room temperature. In particular, an exceptionally large saturation magnetization was observed in one heterostructures film. The growth sequences of \(\hbox {Ba}_{0.7}\hbox {Sr}_{0.3}\hbox {TiO}_{3}\) and \(\hbox {Ni}_{0.8}\hbox {Zn}_{0.2}\hbox {Fe}_{2}\hbox {O}_{4}\) layers on the substrate remarkably affect the magnetic properties of the composite thin films at room temperature.