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In this work, we propose a novel computer-aided design (CAD) model design for metamaterial analysis, based on neuro-space mapping. Neuro-space mapping is a combination of two robust optimisation techniques, artificial neural network (ANN) and space mapping (surrogate-based modelling). The developed model calculates the permeability of a metamaterial unit cell, for which closed-form formula is not available. The model takes the dimensions of the metamaterial unit cell as the input, and then gives the output as the split ring resonator (SRR) dimension. From the SRR dimension, the material parameters are calculated using available closed-form formula. The model is first developed with a Ω-atom unit cell, and then verified applying the model to a deformed-Ω atom unit cell.

Zinc Oxide (ZnO) thin films were produced by the sol gel dip coating process on the p-type silicon substrate with various withdrawal speeds changing from 1 to 4 cm/min, respectively. The films were annealed at a temperature of 500 °C for an hour in air ambient. The thin film thickness was found to be raised with the rise in withdrawal speed. The uniform distribution of the grains was appeared for all the films. The evolution of c-axis oriented (002) peak was revealed from X-ray diffraction (XRD) studies. The microstructural and optical properties of ZnO films were investigated by Raman, FTIR and photoluminescence spectroscopy (PL). The resistive switching properties of ZnO based memristors were studied by performing the current-voltage (I-V) measurements, where the thin films coated with lower withdrawal speed, have shown better switching property with rapid rise and fall of current during SET and RESET process, respectively.

The pervasiveness of cellular telephones, along with rapid advancement in cellular technology, wireless networks and mobile applications, has made them increasingly effective in our daily lives. Individual human activity with respect to travel behaviour is still in a less explored stage. In the past few decades, travel patterns and human activity have become more complex and exhibit a high degree of variations in space and time. In this study, how and in what extent Call Data Records (CDRs) from mobile phones provide the underlying activities of anonymised customers when a user initiates or receives a voice call or message is investigated in detail. Thus, this paper attempts to discover personal human mobility patterns where location, duration and days are the essential attributes in the interpretation of results. Profile-based paging algorithm has been proposed based on the individual human travel pattern. The finding suggests that the proposed algorithm is three times more efficient than conventional paging (blanket paging) and two times more effective than various other intelligent paging algorithms. Further, a substantial saving of about 35% in bandwidth is also obtained from the validation results.

To reduce the possibility of mid-air collisions, Federal Aviation Administration has developed the Traffic-Alert-and-Collision-Avoidance-System. TCAS is mandated worldwide on all large aircraft. In this paper, an overall description of the existing TCAS system is presented, followed by a detailed description of the system and its functional performance. The current collision avoidance system has been in operation for more than a decade. But major transformations to the National-Airspace-System are being implemented through FAA's Next-Generation-Air-Transportation-System in the coming years and that will require substantial modification to the existing system. The development of such new collision avoidance system which is Airborne-Collision-Avoidance-System-X has been pioneered. This survey article also describes the basic concept behind ACAS-X and briefly demonstrates how this new flexible approach in collision avoidance logic is fully compatible with NextGen airspace procedures and technologies. The aim of this work is to review, understand and compare the current and next generation aircraft collision avoidance system.

In mobile access networks, location management is a major and complex issue where location information of the mobile user is essential to deliver incoming calls/SMS to the appropriate mobile stations (MSs). Many metaheuristic algorithms are developed to solve such types of important issue which is responsible for determining the network configuration. This paper proposes a conventional binary genetic algorithm (BGA) approach implemented to reporting cells planning problem in complex multimodal search spaces, since BGA is a conventional algorithm sufficiently able to solve the signalling cost problem along with the modifications in the generic operators. These modifications occur in the mutation operator. The simulation results obtained from the experiments conducted using the existing database along with the real time database. The proposed method shows better performance compared to existing algorithm. This simulation results obtained from the experiments reflects the effectiveness of the conventional BGA.

In this paper, optimisation and experimental verification of a compact zeroth order resonant antenna is presented. It is observed that an antenna can be tuned to a desired working frequency by adjusting the inductive via radius. The antenna is subsequently optimised using HFSS simulation software. Pattern search optimisation is carried out to determine the optimum via radius to achieve minimum reflection coefficient with enhanced bandwidth. Using optimisation we achieved dual band backward wave with a bandwidth of about 2% at 4.28 GHz. After designing and optimisation the antenna is analysed for its performance. The proposed antenna is measured at Antenna Measurement Facility (AMF), ISRO, Ahmedabad. A good agreement between the measured and the simulated results validates the design. The simulated bandwidth at 3.695 GHz covers the IEEE 802.11 wireless local–area network (WLAN) standards. The designed compact antenna is most suitable for precise wireless applications having good radiation characteristics with wide coverage area.