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Technology adoption for school education further gained momentum during the COVID-19 pandemic. However, the challenges and strategies of children belonging to the less privileged (we use 'privileged' in the article to identify those enjoying a standard of living or rights as majority of people in the society) families are different from those of the children who come from socio-economically better-off (privileged) backgrounds. The purpose of this research is to explore the experiences of children with school education and using technology for learning. Past studies have highlighted the use of internet and communication technologies as a promising solution to provide quality school education in the remotest parts of the country. Previous research has also ascertained that the socio-economic status divide has no significant impact on the students' ability to learn using technology. Children can use technology to learn irrespective of their socio-economic status and background. We conducted this exploratory qualitative study from a constructivist grounded theory perspective. A purposive sample of 14 students (9 from underprivileged and 5 from privileged family backgrounds) in the age group of 6-14 years, was used and unstructured interviews were conducted. We analysed the data using constructivist grounded theory methodology. We found that the experiences of privileged and underprivileged children differed with respect to access to internet, affordability of ICT device, quality teachers, parental support, and financial sponsorship. However, the experiences and perspectives of the children were found to be similar with respect to personal ownership of mobile phone device for unlimited time at own disposal, self-directed learning and having a trusted study advisor. The findings may be useful to policy makers and EdTech firms to build strategies and solutions for effective implementation of universal school education in the country.

Background: Phytoremediation, plant usage for remediating natural resources, is being sought as a modern method to clean up polluted lands and streams, including water from ground. Bioremediation assisted by plant, also known as phytoremediation and includes the involvement of microbes associated with certain root systems to remediate soils comprising elevated organic compound concentrations. These strategies could provide cheaper methods for remediating polluted lands and streams with radionuclides, chemicals and different types of organics, with less secondary contaminants and less environmental effect than traditional methods of remediation can produce. All plants consume essential nutrients from their soil and water conditions like metals. Methods: The domestic wastewater quality was determined by analyzing physico-chemical parameters like pH, TDS, TS and electrical conductivity, dissolved oxygen, biochemical oxygen demand, chemical oxygen demand, calcium, potassium, magnesium, sulphate, phosphate, nitrogen, iron and manganese and contaminant removal indices were determined during the year 2018-19. Result: The present study was conducted to check the phytoremediation capability of aquatic plant Ceratophyllum demersum (L.). Wastewater was characterized using standard methods and pollutant concentrations were measured in sample of wastewater initially and after phytoremediation. The result of present study revealed maximum increase in value of DO (127.89%) while the other parameters viz. pH (7.24%), TDS (46.77%), TS (51.00%), BOD (60.79%), COD (58.88%), EC (49.89%), Ca (45.41%), K (46.58%), Mg (43.57%), S (45.21%), P (43.73%), N (42.80%), Fe (46.30%) and Mn (47.06%) recorded a decrease in 60 days at 40% value due to absorption of nutrients during phytoremediation. [ABSTRACT FROM AUTHOR]

The paper deals with the realization of a simple and novel topology of a voltage-mode full-wave rectifier with easy arrangements of a voltage follower, a current follower, two diodes and two resistors. Moreover, an alternative realization using one second generation voltage conveyor, along with two diodes and two resistors is also included. The proposed circuit topology offers rectified output voltage at a suitable low-impedance terminal so that cascaded voltage-mode block(s) may be driven without the need of any additional buffer. The proposed circuit has high performance features such as a wider input linearity range (±0.6 V), rectifying capability of input signal up to 1 MHz frequency, low root-mean-square error (0.316) and low power consumption (0.24 mW). The study of non-idealities, parasitic and frequency behaviour is also discussed to further explore realistic aspects of the proposed idea. Additionally, the proposed rectifier is practically realized and experimentally verified using a single commercial IC of a current feedback amplifier. Furthermore, the MOSFET-based fully active version of the proposed circuit realization focusing on circuit compatibility and feasibility concerns is also explored. The performance of the presented rectifier is examined through PSPICE simulations. [ABSTRACT FROM AUTHOR]

A novel first-order universal filter structure supporting current mode operation is proposed in this paper. The filter has a single active building block based realization and utilizes an extra-X second-generation current conveyor as an active building block. Additionally, the proposed circuit employs a grounded resistor and a grounded capacitor as passive components. The circuit has the ability to deliver the all-pass, high-pass, and low-pass functionalities simultaneously without meeting any passive components matching constraint. High output impedance and load insensitive outputs are other remarkable signal processing features offered by the proposed filter structure. Theoretical behavior of the proposed filter is described by presenting ideal, non-ideal, parasitic, and stability analyses. Additionally, the resistorless variant of the proposed filter is also shown to impart the tunability feature. Personal simulation program with integrated circuit emphasis (PSPICE) simulation results are presented to verify the theoretically described performance of the proposed universal filter. Complementary metal oxide semiconductor (CMOS) realization of extra-X second-generation current conveyor is utilized for the purpose of simulations, therefore, the filter is CMOS compatible. [ABSTRACT FROM AUTHOR]

An extra-X second-generation current conveyor (EXCCII) based first-order current-mode all-pass frequency selective structure is presented through this paper. A grounded resistor and a grounded capacitor are used as passive components. Single active element based realization directly correlates with the circuit's simplicity. The grounded nature of passive components is advantageous from IC fabrication aspects. The proposed circuit offers cascadability support through low input impedance and high output impedance. The ability of the presented idea to deliver the desired output without meeting any stringent component matching condition further simplifies the circuit's operation. Sensitivity performance of the proposed circuit is good. The quality performance at high frequency is another value addition to the circuit's signal processing attributes. Analyses showing the circuit's behavior under non-ideal conditions are also described in detail. Validation of theoretical analyses is supported by simulations carried out on PSPICE at 0.25 μ m technology. [ABSTRACT FROM AUTHOR]

In this work, a three-input single-output structure of current-mode second-order multifunction filter is presented. Two multiple-output second-generation current conveyors serve as the active building blocks. Additionally, two grounded resistors and two grounded capacitors are employed as passive components. On appropriate selection of the input values, all second-order filter functionalities, namely, low-pass, high-pass, all-pass, band-pass and band-reject, can be availed. Proposed filter shows good sensitivity performance and supports high frequency operation. Non-ideal analysis is presented to show the intactness of filter characteristics under runtime conditions. Simulation results show good correlation with the theoretical performance of the proposed filter. [ABSTRACT FROM AUTHOR]

Two new simple and effective voltage mode frequency selective structures that pass all signals are proposed and explored in this paper. The proposed structures use a single active element and three passive components in each. Dual-X second generation current conveyor (DXCCII) is employed as an active element along with two resistors and a capacitor as passive elements. The capacitor is grounded which goes well with the IC fabrication requirements. Both the structures offer low active and passive sensitivities. The presented structures also exhibit the feature of high input impedance. A comprehensive study of device non-idealities and parasitic is also included to highlight the non-ideal performance of the presented ideas. In addition, to prevent the use of passive resistors, resistor less realizations of proposed structures are also explored by replacing the passive resistors with MOS-based active resistors. A quadrature oscillator is also presented as one of the possible applications of the proposed frequency selective structures. Simulations results are in match with the theoretically analyzed performance. [ABSTRACT FROM AUTHOR]