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In this paper, a novel framework for analyzing Physical Layer Security (PLS) of Directional Modulation (DM) techniques has been introduced. The proposed framework maps the concepts of PLS techniques to cryptographic techniques, enabling the analysis of DM techniques as block encryption ciphers. The relevance of the proposed framework has been shown by applying it on Antenna Subset Modulation (ASM). After appropriate physical layer mappings, the encryption strength of ASM is analyzed using National Institute of Standards and Technology’s Statistical Test Suite (NIST’s STS). The performance of ASM is benchmarked against strong block encryption cipher of Advanced Encryption Standard (AES) using data types of image, text, and audio. A new metric, namely Physical Layer Randomness (PLR), has been introduced for direct comparison of encryption strength of PLS techniques to that of cryptographic techniques. The analysis shows that Optimized Antenna Subset Selection (OASS) that reduced average Side-Lobe Levels (SLLs) and improved Symbol Error Rate (SER), has rather adverse effects on encryption strength of ASM. Furthermore, it has been found that scrambling the selection of antenna subsets imparts negligible improvement in PLR.

In this research, photonic simulation is done using Lumerical FDTD software to observe the effect of visible light passing through the Al2O3 and Au nanorod layers. The observed simulation output is the intensity of transmitted light and electric field that has been normalized to the light source. Observations show that there are various phenomena that occur after the light is passed on the Al2O3 and Au nanorod layers, such as changing intensity, wavelength- shifting, and polarization of light wave.

This paper proposes a simple and novel method for estimating a coarse Direction of Arrival (DOA) of a radio source by designing an antenna that would have axial ratio (AR) profile with a unique value of the product of AR and its rate of change at each angle of arrival. This will be achieved by designing a 3D half wave dipole antenna having unique axial ratio profile in the Elevation plane. The technique employed is a 3D reconstruction of antenna by using horizontal and vertical components of electric field projections. The simulation divides a 3D dipole into various sections each with a length $\leq\lambda/10$ and iteratively orienting each at random azimuth and elevation angle using MATLAB and generating a corresponding Numerical Electromagnetic Code file and running it. The output NEC file is then examined for suitable AR profile. This process continues unless a unique AR profile is achieved.

Electronic devices emit unintended radiations as a result of numerous transmission lines printed on circuit board various connectors active and passive devices impact are mismatch amongst these packaging and many other factors. Detection of passive radio frequency (RF) receivers due to their unintentional emissions at a significantly low level is challenging in high level of noise in urban environment that may contain stronger emission sources besides the interval noise of the receiver (Rx). A spying device may consist of both transmit and receive systems. When a signal is being radiated it is easy to detect however such devices might consist of receivers only, which have some storage capacity and the information can be extracted from these later on and analyzed. These receivers which are working in passive mode are difficult to detect. This project explores the efficiency of various methods used to detect such passive receivers. The receivers can be detected passively by receiving their unintentional emissions or actively by impinging an electromagnetic (EM) radiation on it and causing the device to re-radiate these as a result of the incident signal and then detecting those radiations and identifying them.

Daily new cases of COVID-19 as a series of data points ordered in time is one representation of time series data. Our works expect to understand the data characteristics that is related to existing government policies. This paper aims to highlight the impact report and analyses of some COVID-19 policies in East Java province districts. The study is focused on the policy execution before and during the new normal situation of COVID-19 using time series data of new cases as possible and easily observable results. Aside from time series analysis, some visual analysis is performed as well. The experiments focused on some questions related to the policy effectiveness: finding patterns of daily new cases to instigate the need for other local policies and understanding any precedence on occurred cases for nearby districts. Although the second question is not confirmable, the first question verifies more tightened social distancing is still necessary for the new normal.

Sound waves are sensitive to environmental perturbation effects and therefore offer great potential for non-invasive sensing of background temperature, pressure or bio-chemical materials. This paper presents a robust design of electromechanical cavity that can supports high Q resonance for the incident sound waves. The electromechanical cavity consists of subwavelength sized tube residing on a piezoelectric substrate. The cavity utilizes piezoelectric base to absorb and convert incident sound waves to resonant electric currents. At the same time the residue resonant acoustic energy is also back reflected in the form of scattered acoustic fields. The resonator is specially designed to enhance the sound matter interactions towards the base of the cavity and therefore increase the sound energy harvesting many folds. The proposed design of electromechanical resonator cavity system offers potential for low cost and ultrasensitive environmental sensing applications.

Ceramic insulating materials are widely used for HV and EHV applications and were used for many decades. However, these materials response in a polluted environment and lack of hydrophobicity, high maintenance cost, etc., make them vulnerable. From the past decade, polymeric insulators evolved as the best replacement of these traditional materials. However, improvement in long term performance, service life and their aging behavior under different stresses in the field is still a challenging task for researchers. The impact of the environment on the performance of these insulators may vary depending on the severity of environment which necessitates, the proper investigation of performance for different environmental conditions, specifically for the regions having polluted environment. To understand the aging behavior and effects of different stresses on polymeric insulators, various aging techniques are applied worldwide. A lot of research is going on the natural as well as multi stress aging of polymeric insulators. Multi stress accelerated aging is an attractive technique used to simulate the effects of actual field environment and to analyze the long term service performance in a quite short time span. In this paper, the results of 10,000 hours of the aging test under accelerated multi stresses of the polymeric insulators are presented. Silicon rubber (SiR) is chosen from thermoset type and thermoplastic elastomeric (TPE) is chosen from the thermoplastic group. These insulators were applied multi stresses in accelerated weather chamber to be aged. The seasons (summer/winter) and time (day/night) are simulated for the weather cycles. The environmental region of Hattar, Pakistan, was simulated for designing the weather cycles which is an industrial area having high pollution index. The environmental stresses include heat, UV-A, acid rain and salt fog. The insulators selected for aging in this study are known as 10 kV distribution class insulators. The electrical analysis is based on leakage current and physical analysis are discoloration & classification of hydrophobicity, while material analysis technique considered here is Fourier Transform Infrared Spectroscopy (FTIR). This study showed that the TPE insulator lost its hydrophobicity initially with aging while SiR showed better hydrophobicity. Both TPE and SiR showed better leakage current suppression under the simulated environment of Hattar. Investigation of SiR and TPE insulators performance for the long term in the polluted industrial zone and their comparison under the same stresses condition with each other are the two main objectives of the study. Results revealed that both of the insulators are appropriate for the environment.

Cloaking in general refers to hiding objects from the eye, and in particular the radar. This paper reviews the various schemes used for cloaking. Depictions of cloaking in fiction and ancient history have been discussed along with actual work that has been carried out. Various letters related to metamaterials, transmission line network and active cancellation have been reviewed. In the end a general comparison of the different methods is done, and drawbacks are discussed.

Electromagnetically induced absorption (EIA) is a quantum phenomenon which occurs when detuned resonant laser fields interfere via atomic transition pathways. The transmission spectrum of a material experiencing EIA consists of an enhanced narrowband absorption line in between the two laser resonances. In this paper, we implement near-field interference of two microstrip radiators to produce a similar absorption mechanism. We propose a practical sensing application to detect foliage moisture by detecting the resonance shifts when sample leaves are made to perturb the near-field radiations. For the sensing, we exploit the anomalous phase signature that accompanies the EIA effect, instead of the amplitude signatures traditionally used in contemporary microwave sensors. The sensing using phase spectrum performs better than the amplitude-based sensing in harsh environments affected by noise and external interferences. Since the proposed EIA-based detector exploits multiple antenna interference in the near field, resonant sensing over distance is also possible. We demonstrate practical moisture detection using actual foliage samples with different moisture levels. We also develop a numerical dielectric model to estimate foliage moisture using full-wave electromagnetic simulations. We anticipate, from this paper, a way to produce low-cost and non-invasive microwave sensors that have reasonable sensitivity and which can be used in remote areas subjected to extreme weather environments.

In this paper, simulation of 2-bit SONOS (silicon-oxide-nitride-oxide-silicon) nonvolatile memory is perfomed. This single device cell has a two physical bit storage capability. Moreover, The method is based on characterization of localized trapped-charge in the nitride layer. Programming is performed by channel hot electron injection. Furthermore, The read methodology is based on drain induced barrier lowering (DIBL) mechanism and very sensitive to the location of trapped charge in storage layer. In this design sentaurus Tcad tool in 130nm technology is used.

In this paper, Carbon Monoxide (CO) gas sensor deposited on the Alumina substrate was fabricated by synthesizing a nanocomposite of Zinc Oxide (ZnO) and Graphene as a sensing layer via the hydrothermal method. ZnO-Gr nanocomposite was varied with ratio of 1:1, 1:3, and 1:5 to obtain the optimum composition in responding to CO gas. The sensing layer was exposed by CO gas to 5 concentration variations at room temperature and 1 concentration at 2 high temperature. Morphological structure of ZnO-Gr was presented through Scanning Electron Microscopy (SEM). It was found that ZnO-Gr nanocomposite with ratio of 1:3 at room temperature generated the highest % response to CO gas sensing. Decreased resistance occurs in step of increasing temperature. The property of semiconductor changes from p to n-type above $100^{\circ}C$; C temperature to CO gas exposure.

This study investigates the effects of variation of Vds and Vg on trapped charge in SONOS NVSM using Synopsis Sentaurus TCAD Simulator. We variate both drain voltage (0 volt/1volt/3volt/5 volt), gate voltage (3volt/4volt/5 volt). The result show that the trapped charge in SONOS memory vary when the programming voltage is changed. Moreover, we investigate the amount charge in 10 years after programming state. In this condition, Programming state of 3V gate and 5V drain have the smallest change in the rate of trapped charge after 10 years compared to the other variated voltage.

The classical electromagnetic (EM) and acoustic waves interact with metamaterials in interestingly resembling manner. A robust technique is described to retrieve effective medium parameters for both acoustic and electromagnetic fields using scattering parameters as input. To establish the applicability of technique a Fano resonator metamaterial is designed that supports response in EM and acoustics regime. The acoustic wave interaction with metamaterial exhibit exclusive negative band of effective bulk density (P eff ). On the other hand, electromagnetic wave interaction with metamaterial gives negative band of effective permittivity ( $\epsilon_{\text{eff}}$ ). The proposed method to extract effective medium parameters for classical waves interacting with metamaterials offers potential for design and characterisation of micro/nano electromechanical systems MEMs/NEMs.

A metascreen absorber composed of plasmonic nan-odisk array is used to absorb incident radiation at optical frequencies. The conventional Nobel metals such as gold and silver are considered as best plasmonic materials to couple incident light to surface plasmons modes. However, it is found that alternative plasmonic materials such as copper (Cu) offers optimized absorption characteristics. Copper nanodisk absorber offers a broad range of optical absorption ranging from 400 nm - 1500 nm wavelength. In addition, it is found that the light absorption bandwidth can be significantly enhanced or near perfect absorption can be reached if plasmonic nanodisks are arranged in quasi-crystal configuration. The proposed quasicrystal based metascreen absorber offers potential applications for light energy harvesting and optical sensing applications.

With superior electrical properties, easy handling and low weight, polymeric materials are used for external insulating materials for outdoor and indoor applications. However, with the presence of environmental stresses such as contamination, and humidity in the environment, surface tracking and erosion may happen to polymeric insulating materials. Therefore, resistance of tracking of polymeric insulation materials is an important property to be investigated in recent years. Moreover, Polymer nano-composites/micro-composites have attracted wide interests in various industries. IEC 60587 standard (Inclined Plane Test (IPT)) gives a method for the evaluation of the tracking resistance in polymeric insulating materials. In this paper, the IPT method has been used to evaluate the performance of the polymeric insulators under AC voltages. Tests were conducted on polymer High Temperature Vulcanized Silicone Rubber (HTV-SiR) with fillers (nano+ micro silica) under AC stress. In this article, simultaneous addition of nano and micro sized filler is used to improve the erosion/tracking resistance of base material. Leakage Current, Initial Tracking Voltage (ITV), and Infrared thermographs are taken after every hours according to the IEC-10586 standard. After conducting test, overall Hybrid Samples have the improved resistance to tracking with the lowest leakage currents. However, among hybrid, sample EN1 (2% nano SiO2+20% micro SiO2) is the one with improved results. Leakage current, ITV and Infrared thermographs data support the above results.

Commercial soil moisture measurement devais based on time-domain reflectometry (TDR) are considerably expensive for daily practice by Indonesian farmer. In this paper, we present development of a low cost microcontroller based electronics soil moisture measurement system using TDR. We utilize the equivalent time sampling technique to enhance range of measurement frequency while the sigma delta modulation is used in implementation. Our sensor system is based on M-4 ARM Cortex microcontroller, working on a 100- KHz signal and virtual sampling resolution within 0.11 ns. The developed sensor system was able to reconstruct a typical TDR wave with reflection within several nanoseconds.