Coronavirus disease 2019 (COVID-19) outbreak that was declared as a pandemic by the World Health Organization (WHO) on 11 March 2020 has already had severe consequences in all aspects of people’s lives worldwide. The pandemic has affected over 200 countries and has become a major concern. India also faced a stiff challenge in terms of controlling the virus outbreak and through some strict measures such as nationwide lockdown was able to control the further spread of COVID-19 towards the latter part of 2020. Therefore, it is imperative to predict the spread of this virus along with causality analysis of parameters that play a significant role in its spread. The present study employs a series of univariate and multivariate time series forecasting techniques namely MSARIMA, ARMAX and extended VAR models to predict COVID-19 cases in New Delhi, Mumbai and Bengaluru. Besides, providing a robust forecasting performance for COVID-19 cases, the study also deals with finding the causal relationship of the spread of COVID-19 with various mobility and weather parameters. Outcomes of our study establish that the spread of COVID-19 can be associated with mobility and weather parameters apart from the various precautions that are taken by the people to reduce community transmission. However, the type of mobility (residential, retail and workplace) and type of weather conditions (air quality, temperature and humidity) associated with the causality differ with cities. For New Delhi, air quality, residential, retail are the parameters affecting the spread of the COVID-19 cases, whereas masks, temperature, residential and workplace were the significant mobility and weather parameters for Mumbai. In addition, for Bengaluru, the statistically significant causal variables were air quality, masks and residential. Outcomes of this study would help the concerned authorities to predict and contain future COVID-19 spreads in Indian cities efficiently.

This paper addresses the position control of antenna azimuth using proportional and integral (PI) controller and lead compensators. The fractional order calculus plays an important role for designing the robust control. The fractional order lead compensator is proposed for enhancing the closed loop performance of azimuth position control of antenna system. From the comparison of the closed loop responses, the proposed lead compensator delivers a superior closed loop performance when compared with PI controller and lead compensator.

Abstract:In developing countries, particularly many rural areas are in need of reliable and low cost electrical system which supplies water for rural areas. To solve this problem, an efficient water pumping system has to be designed to supply agricultural farms and rural settlement. For these applications, solar water pumping system is the most appropriate solution. This paper presents design and comparison of solar water pumping system with PID and FUZZY controllers for agricultural and domestic applications using MATLAB Simulink. In this project DC-DC boost converter is used to step up the voltage to a suitable value which is suitable to run the induction motor A design of directly coupled solar water pumping system powered from photovoltaic panels, DC to DC boost converter, full bridge sinusoidal pulse width modulation inverter, LC filter, induction motor and centrifugal pump is presented. The PID and FUZZY controllers used to control the voltage and compared the performance of the system with PID and FUZZY controllers.

James Simmons’s early research on sonar ranging in echolocating bats generated two groundbreaking discoveries: (1) Bats compute object distance from the time delay between sonar calls and echoes, and they discriminate echo-delay differences in the microsecond range [Simmons, https://psycnet.apa.org/doi/10.1121/1.1913559 (1973)] and (2) A population of auditory neurons show facilitated and echo delay-tuned responses, a posited neural substrate of sonar ranging [Feng et al., https://10.1126/science.705350 (1978)]. These findings spawned decades of biosonar research around the world, and this talk will summarize three new findings on the mechanisms of sonar ranging in the big brown bat, Eptesicus fuscus. (1) Echo-delay tuned neurons in the midbrain of the free-flying bat show 3D spatial tuning to echoes from physical objects, and sonar-guided attention evokes sharper delay-dependent response areas and shifts to shorter echo delays. (2) Local field potential recordings from auditory midbrain neurons in the passively listening bat encode the time interval between call-echo pairs in the microsecond range, with accuracy dependent on signal duration and bandwidth. (3) A population of hippocampal CA1 neurons encodes the distance of sonar objects in bats as they track moving targets, and responses of hippocampal neurons depend on the production of sonar calls that yield echo returns.

This work deals with the problem of the propagation of an elastodynamic field radiated by a source in a cylindrical layered medium which interacts with and is diffracted by a defect. At low frequencies, where the defect size is much smaller than the wavelength, this interaction can be approximated by a point source, located at the defect position. This secondary source is expressed by the Green function and its derivative. The Green function, which describes the response of an undamaged cylinder, is calculated using the canonical form of the wave equation initially expressed as a function of the spatial and temporal variables. Performing the Laplace in time and Fourier transforms along the cylinder axis, this equation is written as an ordinary differential equation with respect to the radial position. The solution for the transversely isotropic case is obtained by adopting the partial wave formulation, expressed as a combination of the modified Bessel's functions of the first and second kind. Having assembled the layers, numerical inverse transforms are performed to obtain the real wave fields. This technique allows for reduced computational costs and faster calculation times and could be used for the non destructive testing of embedded pipes and tubes.