040924   OGUNLEYEA O O, ARINKOOLAA A O, ALAGBEA S O, AGBEDEA O O, OMODELEC A E, MORAKINYOA A F, OSHOA Y A (Chemical Engineering Dep, Ladoke Akintola Univ of Technology, Ogbomoso PMB 4000, Nigeria) : Synthesis of green corrosion inhibitor for mild steel in acidic environment. Indian Chem Eng 2020, 62(1), 52–66.

The inhibitive potential of Mondia whittei roots extract (MWE) on corrosion of Mild Steel coupons in 0.5 M HCl solution was investigated by weight loss, depth of attack and surface analysis. Effect of various parameters, such as concentration of MWE, immersion time and temperature on inhibition efficiency was studied. The identification of the constituents of MWE and characteristics of the test solution and adsorbed film on the test coupon were evaluated by Gas Chromatography/Mass Spectrophotometer (GC-MS) and Fourier Transform Infra-Red (FTIR) Spectrophotometer. The surface morphology and topographical features of the corroded mild steels were done by the scanning electron microscope (SEM). The main constituents responsible for corrosion inhibition properties of MS were found to be guaiacol, vanillin, 9, 12- octadecadienoic acid and phenol, 2, 6-dimethoxyl among many other components which contain C, H and O. A maximum corrosion inhibition efficiency of 89.47 % was obtained with 1.0 g/L in 0.5M HCl at 60°C after 9 h and volume – area ratio of 40 mL/cm² . Polarisation curves reveal that the inhibition efficiency according to depth of attack given by R_a and R_z increased with increasing inhibitor concentration, temperature, time and volume – area ratio.

6 illus, 6 tables, 47 ref

042687   TIWARI G, CHAUHAN R C S (Electronics Engineering Dep, Institute of Engineering & Technology, Lucknow, Email: gayatri.10nov@ gmail.com ) : A review on inter-satellite links free space optical communication. Indian J Sci Technol 2020, 13(6), 712 – 24.

The need for constricting, lightweight, low-power electronics-aggravated by the thriving demand for large data flow rate and bandwidth is urging the use of optical technologies in defense and space. Free space optical (FSO) communication links have promising eminence over microwave communication links with high speed, low weight, and increased security so that they can be boarded conveniently on the satellite. The advancement of the optical components and systems has made it very predominant along with its acceptability in space and defense. Yet a couple of significant components to be dealt with are tracking problems with misalignment of the transmitter and receiver apertures and the progressions because of barometrical conditions. Efficiency of the FSO communication system is seriously rotted due to the angle of arrival (AoA) variance and including error pointing. The optical transmitter can be perfectly coordinated with the receiver by utilizing the pointing, acquisition, and tracking (PAT). However, this method is to be carried out under the airborne platform with required restrictions namely size, weight, and power. An overview of promising inter-satellite applications with the challenges have been discussed which sway the performance of the system and make the communication link unattainable. The FSO communication possesses an advantage over two existing technologies optical fiber communication and wireless communication. Hence, the significant use of FSO is intersatellite optical wireless communication (Is OWC) links, which will be deployed in the future in space.

5 illus, 1 table, 45 ref

042686   ESPINOSA F H T (Industrial Engineering Dep, del Bío-Bío Univ, Concepción 4030000, Chile, Email: ftroncos@ubiobio.cl ) : Prediction of recidivism in thefts and burglaries using machine learning. Indian J Sci Technol 2020, 13(6), 696 – 711.

Theft and burglary are two crimes against property that have a great social impact. Their prevention drastically lowers victimization rates and the feeling of insecurity in the population. The objective of this investigation is to obtain an index that allows the prediction of repeat offenses by criminals in these types of crimes, in order to support decision-making with respect to preventative actions. In order to obtain the index, a group of machines learning was trained, with information provided by the Criminal Analysis and Investigative Focus System (CAIFS) from the Regional Public Prosecutor’s Office in Biobío, Chile. The information provided was from thefts and burglaries committed between 2012 and 2017 in the city of Concepción. The results show a characterization of repeat offenders in these types of crime and a recurrence index that allows for a greater assertiveness in the prediction of recidivism than the method that is currently being used.

3 illus, 6 tables, 41 ref

042681   MAHESAR M R, MAHA M AR, LARIK A S, SOLANGI M H (Electrical Engineering Dep, Mehran Univ of Engineering Technology Jamshoro, Pakistan, Email: mahesar85@gmail.com D) : Comparative analysis of three-phase single active bridge dc-dc converter with different mode of conduction with transformer vector groups. Indian J Sci Technol 2020, 13(6), 630 – 45.

This research study compares the performance of a three-phase single active bridge DC-DC converter with several operating modes along with vector groups in order to present the importance and applications of transformer vector groups in the electrical network system. In order to analyze and compare the operating characteristics of three-phase single active bridge converter with vector groups of transformer. Initially, we made a detailed study of vector groups of transformers through literature review. Then the development of simulation model of three-phase single active bridge DC-DC converter with transformer vector groups while operating with different operating modes of three-phase inverter by using MATLAB/SIMULINK software was made. We investigated Total Harmonic Distortion (THD) in terms of voltage and current waveforms with both resistive and inductive load of SAB3 converter with the different transformer vector group while operating with different modes of conduction, i.e., 120, 150, and 180. Undoubtedly, today’s world is moving towards replacing fossil fuels with renewable energy resources. Three-phase single active bridge DC-DC converters are widely advantageous. From the simulated results, it is clear that at 150-operating mode, the SAB3 generated fewer harmonics in terms of voltage and current for both resistive and inductive load as compared to other operating modes.

18 illus, 7 tables, 17 ref

042679   KHAN A N, BHEEL N, AHMED M, ABBASI R A, SOHU S (Civil Engineering Dep, H.C.S.T Hyderabad, Sindh, Pakistan, Email: udasinarain@ gmail.com ) : Use of styrene butadiene rubber (SBR) polymer in cement concrete. Indian J Sci Technol 2020, 13(5), 606 – 16.

This research work was adopted to have the maximum strength of concrete mixed with styrene-butadiene rubber (SBR) and to know the effect of SBR on the fresh and hardened concrete. The concrete samples were prepared to achieve targeted strength of 3000 lb/in². In this experimental work, the mixture of concrete was prepared by adding 0 %, 5 %, 10 %, 15 %, and 20 % of SBR polymer–cement ratio to check the properties of fresh concrete (slump test and compaction factor test), while rebound hammer test, ultrasonic pulse velocity test (UPV), compressive strength test, and tensile strength test were observed at 7th, 14th, and 28th days, respectively. Resultantly, the compressive strength and indirect tensile strength boosted by 16 % and 13 % blended with 15 % of SBR polymer in concrete as compared to control concrete after 28th days, respectively. The workability of fresh concrete plummeted with a rise in the amount of SBR polymer in concrete. Both the quality and high strength of concrete is improved by adding 15 % of SBR in concrete.

7 illus, 2 tables, 28 ref

040923   ALALWAN H A, ABBAS M N, ALMINSHID A H (Mechanical Technical Dep, Middle Technical Univ, Baghdad, Iraq) : Uptake of cyanide compounds from aqueous solutions by lemon peel with utilising the residue absorbent as rodenticide. Indian Chem Eng 2020, 62(1), 40–51.

Lemon peel was examined in this work as innovative inexpensive biosorption material for cyanide (CN⁻) removal from aqueous solution. The influence of adsorbent amount, feed flow rate, CN⁻ concentration, and solution pH on the breakthrough and saturation points was determined. To determine the design parameters required to scale-up the system, this work explores six different kinetics models. The data showed that the breakthrough curve is highly dependent on the investigated parameters. The system showed perfect performance, achieving more than 99 % removal of CN⁻ at the optimum conditions for the first 25 min. Furthermore, this work examined utilising the used adsorbent, saturated lemon peel with cyanide, as inexpensive rodent pesticide by tested on an outbred multi-purpose breed of albino rats and compare the results with the median lethal dose (LD₅₀) for those rats. The test results showed a foetal effect of the adsorption residue on the rats. This step will assure a safe method to dispose of the adsorption residue, as well as provide an inexpensive rodent pesticide, which increases the economic feasibility of this removal technique.

6 illus, 1 table, 46 ref

042677   HEKMATIPOUR F, JALALI M, MAROUFI A, HEKMATIPOUR F (Hydraulics and Heat Engineering Dep, Don State Technical Univ, Rostov on Don, Russia, Email: farhad. hekmatipour@gmail.com) : Rostov on Don, RussiaEnergetic and exergetic analysis of the lowtemperature heating system in a model library. Indian J Sci Technol 2020, 13(5), 587 – 96.

Energetic and exergetic analysis of the low-temperature heating system in a model library are conducted numerically in this research. The method of numerical investigation and simulation are employed to compute the energetic and exergetic analysis of the low-temperature heating system in a model library. The use of C++ programming and Hourly Analysis Program software were done the simulation and optimization. The results of this investigation are presented in this article. Simulation presents that the most of energy which is required for heating is capable to be declined using low-temperature heating system in a model library. It is shown that gas consumption decreases when lowtemperature radiators are applied and the value which is obtained is about 61,458,480 m³/yr. This means that the performance of the lowtemperature radiation is better than high-temperature radiator and it is about 57,150,000 m³/yr. The use of low-temperature radiators and high-temperature radiators are compared in this article. The radiator quality factor of the low-temperature radiators and hightemperature radiators are obtained 0.13 and 0.22, respectively. By using the low-temperature method, radiator quality factor is able to be declined 7 % of the energy efficiency. Based on these cases, using the low-temperature system can be used in some regions in Iran. The economic investigation shows that the IRR is evaluated based on discount 30 %, and interest rate 22 % in 20 years. The declination of energy consumption in building is significant. Therefore, a method which can use to reduce energy consumption is low-temperature heating in winter.

2 illus, 2 tables, 22 ref

040920   UTTARAVALLI A N, DINDA S (Chemical Engineering Dep, BITS-Pilani Hyderabad Campus, Hyderabad - 500 078) : Studies on synthesis of environment-friendly products for paint and coating applications. Indian Chem Eng 2020, 62(1), 1–14.

In the study, environment-friendly products, such as ketonic resins were prepared by self-polymerisation of ketonic monomers in the presence of a base catalyst using a high-pressure batch reactor. The crosspolymerisation reactions of ketonic monomers were also examined in the work. The effects of reaction parameters, such as reaction time, temperature, catalyst concentration and monomer concentration on physico-chemical properties of the product, such as physical state, hydroxyl value, iodine value, acid value, viscosity, average molecular weight, solubility, softening temperature and thermal stability have been studied. From the results, it was observed that the polymerisation reactions with methylcyclohexanone (MCH) or cyclopentanone (CP) monomers offered high viscous liquid resins. However, addition of small proportion (5–10 wt %) of MCH or CP along with cyclohexanone (CH) can play a significant role in obtaining a better quality product. It was also observed that CH and MCH monomers offered white colour resins, whereas CP monomer offered brown colour resins. The in-housedeveloped resins are thermally stable up to a temperature of around 180°C. From the overall investigation, it can be concluded that the inhouse-developed ketonic resin products can be a suitable substitute of alkyd, ketone−aldehyde or phenol−aldehyde resins for paint and coating applications.

9 illus, 7 tables, 24 ref

042673   TAPCHE R W, KENGNE J, NJITACKE Z T, PELAP F B (Electrical Engineering Dep, Dschang Univ, Cameroon, Email: wafotapche@gmail. com) : Uncertain destination of a 4D autonomous system with five line equilibria. Indian J Sci Technol 2020, 13(5), 519 – 38.

This paper introduces a novel 4D autonomous dynamic system with five line equilibria and a smooth nonlinearity. The new model is obtained by adding one more freedom degree to the 3D jerk system recently introduced by Kengne and Mogue, 2018. To analyze and study the model, Ruth criterion principle is used for the stability of different lines equilibria. Using traditional dynamics tools such as bifurcation diagrams, phase portraits, Poincare section, power spectrum, and Pspice software, the dynamic of the system is carried out. The new elegant system has an extremely rich dynamics predominated by the phenomenon of extreme multistability. The various sequences of coexisting route to chaos (coexisting bifurcation) confirm the uncertain destination of our novel elegant system. Note that, for the best of author’s knowledge, this is one of the best reproducible extreme multistable system because is not a flux control memristorbased system. The results obtained in this investigation enrich the literature and being used to improve the extreme multistability application in many research domains such as Random Number Generation (RNG) and image encryption.

10 illus, 1 table, 30 ref

042672   ONONOGBO C, NWUFO O C, OKORONKWO C A, OGUEKE N V, IGBOKWE J O, ANYANWU E E (Mechanical Engineering Technology Dep, Imo State Polytechnic, Umuagwo, Owerri, Imo State, Nigeria, Email: petermaryco@yahoo. com ) : Equipment sizing and method for the application of exhaust gas waste heat to food crops drying using a hot air tray dryer. Indian J Sci Technol 2020, 13(5), 502 – 18.

Equipment sizing and method of utilizing exhaust gas waste heat for food crops drying are presented. The sizing of the components of the equipment was achieved using known design principles. The system uses an axial flow turbine and a heat exchanger to harness the energy of the exhaust gas of a diesel engine generator. A 250 kVA generator with measured exhaust gas flow rate and temperature of 44.5 m³/min and 382.7 °C was selected for this work. The purpose of the recovered energy is for the drying of food crops. An arduino platform was used to control the operation of the components of the dryer. The drying chamber consists of three trays whose calculated total volume per batch is 0.0463 m³. Weight losses across the trays, drying air temperature and humidity in the chamber are monitored by sensors. The test rig of the sized and fabricated equipment is currently undergoing extensive experimentation. Preliminary investigation of the dryer showed that the drying air in the chamber initially at the temperature and humidity of 31 ºC and 71.2 % was heated to 88 ºC and 22.3 % when the dryer operated without load for 45 min at an air speed of 2.0 m/s. After cooling and maintaining the drying chamber averagely at 59 ºC, each tray was loaded with 400 g of the grains of freshly harvested maize. The dryer was allowed to run for 30 min and the results obtained showed weight losses of 127.81 g, 118.36 g, and 116.91 g for the grains in trays 1, 2, and 3, respectively. The application of this energy recovery system to the drying of food products, would help to save a considerable amount of primary fuel which is considered a viable means of cost saving and amelioration of environmental degradation. 

6 illus, 3 tables, 22 ref

042669   BHEEL V M, SHAIKH A A, MEMON A A, AWAN S K, TALPOOR M A (Basic Engineering Dep, Sindh Agriculture Univ, Tando Jam, Sindh, Pakistan, Email: veeromal@ sau.edu.pk) : Development of inverse mathematical model of rouse formula to estimate suspended sediment concentration along width of channel. Indian J Sci Technol 2020, 13(4), 460 – 74.

The sedimentation is a burning issue all around the world; hence this research will help the irrigation engineers to solve the sedimentation problems related to irrigation channels, hydraulic structures as well as in the field of agriculture. In this present research study, the inverse mathematical model of Rouse formula is developed to calculate the suspended sediment concentration along the width of an open channel. For derivation of the model, a well-known differential advection–diffusion equation is solved analytically with respect to x-axis along the width of channel. The model is also validated and checked with experimental results and calculated results by the newly developed model. A mathematical model has been developed for suspended sediment concentration along the width of channel. Furthermore, this model applied and compared with experimental results and observations which were conducted in open channel. Finally, for more validation and reliability of a newly developed model, the average maximum and minimum percentage errors are computed. These errors indicate that the proposed model has the best accuracy and resemblance when percentage errors of the newly developed model are computed. A newly developed model can be applied to estimate suspended sediments concentration from open channels. This model is also useful for irrigation engineers to find out suspended sediments concentration profiles along the horizontal direction from the centre to channel banks at the mid-depth of water. 

5 illus, 6 tables, 11 ref

042648   GHANIM A A J (Civil Engineering Dep, Najran Univ, Najran, Saudia Arabia, Email: aaghanim@nu.edu.com ) : Modeling rainfall runoff relations at arid catchments using conceptual hydrological modeling approach. Indian J Sci Technol 2020, 13(3), 329 – 39.

To develop a simple deterministic lumped conceptual rainfall-runoff model. This study developed a model based on the water balance, in which the model tracks precipitation, simulated soil water content, surface runoff, evapotranspiration, percolation, and return streamflow. The major input requirements for this model are hourly rainfall, hourly potential evaporation and the average daily streamflow record. The model is calibrated and tested using the available data collected from only one semi-arid ephemeral catchment located in the central part of Jordan. The model was optimized using Shuffle Complex Evolution (SCE.UA) optimization method. The performance of the model was evaluated using the goodness of fit measures. The simulation results obtained show that the proposed model has a good match between observed and simulated streamflow for both optimization and validation stages. The good simulation results obtained indicate that the model will be useful in design of hydraulic structures and for effective management of water resources at arid and semi-arid catchments. In order to strengthen the validation and applicability of the proposed model, empirical research needs to be conducted. Further research is required to assess the predictive uncertainty associated with model parameters and other inputs.

4 illus, 1 table, 14 ref

042646   ZAHEER M O, SHAIKH A A, SHAIKH F (Mehran Univ of Engineering and Technology, Jamshoro - 76090, Pakistan, Email: Osama.mth.st@gmail.com ) : Analysis of unsteady mhd thin layer flow of fourth-order fluid through a vertical belt. Indian J Sci Technol 2020, 13(3), 299 – 315.

To study the unsteady magneto-hydro-dynamic (MHD) thin layer flow of a fourth-order fluid through a moving and oscillating belt. The well-known analytical technique, namely Adomian decomposition method (ADM) is used to solve the non-linear partial differential equation for governing equations of velocity profile with subjects to initial and boundary conditions for both lift and drainage problems. The solution is found in excellent agreement. The basic purpose to study the effect of MHD on velocity field and understand the behavior of this physical problem and the effects of different non-dimensional parameters the graphical results are provided.

12 illus, 12 ref

040870   GUPTA N, VEMPATI V, AGARWAL A (Aviation Pathology & Toxicology Dep, Institute of Aerospace Medicine IAF, Bengaluru - 560 017, Karnataka, Email: nehagupta17sep@gmail.com) : Dietary deficiencies among families of air warriors: Use of iron deficiency anemia as an index. Indian J Aerosp Med 2020, 64(1), 27-31.

Anemia is a prevalent health problem in India affecting all age groups. It has shown the highest prevalence among preschool children and occurs more commonly in the lower socioeconomic group. Observationally, it was noticed at an Air Force station that preschool children of air warriors had iron deficiency anemia at levels similar to those seen in lower socioeconomic groups. This prompted us to evaluate dietary practices among families of air warriors as a contributory factor to iron deficiency in these children. All anemic children diagnosed of iron deficiency in the age group of 6–59 months were included in the study. Data were compiled from the clinical history, dietary habits and laboratory parameters obtained. The dietary habits were analyzed based on parameters defined in the current infant and young child feeding guidelines such as exclusive breastfeeding, minimum meal frequency, minimum dietary diversity, and minimum acceptable diet. Mann–Whitney U-test was used to determine statistical significance of difference between means of two independent groups. Spearman correlation analysis between two independent variables was done and multiple linear regression analysis was performed to identify predictor variables for iron deficiency anemia. About 74.1 % of the anemic children fell into age group of 6–23 months (infants and young children). 75 % of children of the age group of 6–23 months were started on cow’s milk at the time of weaning. The average amount of cow’s milk consumed in a day was 0.7 L. In this age group, the minimum dietary diversity was observed in 11.1 %, minimum acceptable diet in 5.5 % and minimum meal frequency in 22.2 % of the children. In the same age group, a statistically significant negative correlation was observed between cow’s milk quantity given per day and hemoglobin (ρ = ‒0.77). A significant negative correlation was found between cow’s milk quantity and variables such as age and number of solid meals received in a day (ρ = ‒0.553 and –0.526, respectively). In multiple regression analysis with hemoglobin as the dependent variable, a significant negative association was observed with cow’s milk quantity. Age showed statistically significant positive correlation with hemoglobin (ρ = 0.762) which was also seen on linear regression analysis. Serum ferritin was low in 44.5 % while total iron-binding capacity was raised in 100 % of the cases. Iron deficiency anemia was disproportionately distributed among infants and young children (age group 6–23 months). Copious consumption of cow’s milk in this age group led to fewer solid feeds per day and lack of dietary diversity which led to an iron deficient state in these children. This probably resulted in manifestation of anemia in this population. The study brings out the need for dietary counseling for air warriors and their families to ensure better health and lower disease burden.

4 tables, 10 ref

040869   NARAYANAPPA D, SOWGANDHI C N, TRIPATHY N K, AGARWAL A (SMC, Chabua, Assam, Email: drdivya.n22@gmail.com) : An appraisal of happiness in civil aircrew. Indian J Aerosp Med 2020, 64(1), 23-6.

Commercial aviation is a unique occupation, where the professional responsibility to ensure the safety of the aircraft and its occupants lies with the pilot, making civil aviation a stressful and demanding job. Psychological fitness plays a crucial role in helping aircrew adapt to and deal with these occupational demands. In the past few years, the awareness and interest in mental health among civil aviators and the aviation industry have been on the rise. Happiness is characterized as a lasting state with positive emotions and life satisfaction. It is known to improve performance and reduce stress. Based on this, the main objective of this study was to conduct a survey to appreciate the level of happiness among civil aircrew. A widely used scale for assessment of happiness called Oxford Happiness Questionnaire (OHQ) was administered to both male and female civil aircrew (n = 100). OHQ is a 29-item self-reporting questionnaire. Internal consistency was calculated using Cronbach’s alpha which was found to be 0.97 on the current sample. Data collected were also studied to find a correlation between demographic variables and happiness index. A mean score of 4.87 was obtained in the OHQ which indicated that the civil aircrew perceived themselves to be quite happy. No significant relationship was found between age, experience, marital status, and happiness scores. This was a unique survey in which civil pilots flying both domestic and international flights from India were assessed in terms of their happiness level as a measure of psychological well-being. The participants consisted of a total of 100 aircrew, consisting of 87 males and 13 females. The happiness index in this sample was found to be moderate to high. Most of them perceived their lives and work to be meaningful, which led to high motivation and increased performance. The results also revealed that flying hours of civil aircrew had no significant relationship to happiness level, further indicating that age and experience of the pilots did not predict their happiness, which was akin to a number of researches conducted on the general population. Although the aircrew were found to be moderately happy, the happiness level could still be increased. Small and modest actions by both the aircrew and the airline industry may make a big difference to the happiness state of aircrew.

3 illus, 1 table, 12 ref

040868   BISWAL P, SWAMY S G (Human Engineering and Human Factors Dep, Institute of Aerospace Medicine IAF, Bengaluru - 560 017, Karnataka, Email: drpunyashlok@gmail.com) : Optimizing sizing schedules of aircrew helmets using machine learning techniques. Indian J Aerosp Med 2020, 64(1), 18-22.

Aircrew equipment assemblies are life critical equipment worn by the aircrew to ensure protection from various life-threatening environmental conditions that may occur in nominal or off-nominal flight conditions. It is important for the sizing system of body worn aircrew equipment to be divided into different size classes such that it is as representative of existing groups in the population as feasible. Machine learning techniques provide a powerful tool to develop efficient sizing systems that are representative of actual body types existing in the population. The objective of the study was to use machine learning clustering techniques to identify naturally existing body types to formulate an optimal sizing system for an aircrew helmet. The standard sizing schedule of an aircrew helmet using head length and head breadth was studied. An iterative semi-supervised machine learning protocol called K-means clustering was used to identify naturally occurring clusters of head types within the population. The cluster boundaries were identified to develop the final sizing schedule. Analysis of variance (ANOVA) with post hoc analysis was carried out on the four head lengths and head breadths. Four clusters of head type were identified using K-means clustering. This led to a sizing schedule which can be descriptively called “Short-Narrow,” “Short-Broad,” “Long-Narrow,” “Long-Broad.” ANOVA showed a statistically significant difference between the four clusters for both head length and head breadth. Consideration of several variables in sizing schedules often fails to meet desired fitment. Standard sizing methods use linear partitions on individual control parameters. In reality, the proportional variation between parameters is not linear. Machine learning tools help in identification of naturally occurring clusters within the database considering several variables at the same time. This study uses machine learning techniques to identify existing groups in a population and develop a final sizing schedule. Similar analysis for other aircrew equipment assemblies can be carried out to determine sizing schedules which assist in design and fitment.

3 illus, 1 table, 14 ref

042632   ULLAH N, KHAN F, KHAN A A, KHAN S, TAREEN A W, SAEED M, KHAN A (Balochistan Univ of Information Technology Engineering and Management Sciences (BUITEMS), Quetta, Pakistan, Email: najeebullah.hasni@ gmail.com ) : Optimal real-time static and dynamic air quality monitoring system. Indian J Sci Technol 2020, 13(1), 91 – 102.

The objective of this study is to design and implement an effective low-cost air quality monitoring system that has the ability to monitor real-time air quality over a wide geographical area. The proposed system is developed for CO and NO₂. As a test case, our developed system is deployed in Quetta city, both in static and dynamic situations and the concentration level of CO and NO₂ in the air are measured and stored, along with their time, date, and location. In order to analyze this information, the stored data are then transferred to a data collection center via short-range wireless communication. Many air quality monitoring systems exits in the market; however, most of these systems have several design limitations such as size, cost, inability to move, and demand for continuous internet connectivity. Therefore, in this study, we have designed and implemented an effective low-cost air quality monitoring system that has the ability to monitor real-time air quality over a wide geographical area. Moreover, unlike existing air quality monitoring systems, the proposed system does not require any continuous internet connection and it can monitor the concentration level of pollutants in the air both in a static position and in mobile situations. The test results show that our proposed system can perform very well in both static and mobile situations. The proposed monitoring mechanism can help environmental experts and the general public to develop a more robust strategy against the adverse effects of air pollution. 

9 illus, 2 tables, 22 ref

042552   SHARMA R P, RAJU M C , GHOSH S K , MISHRA S R, TINKER S (Mechanical Engineering Dep, National Institute of Technology Arunachal Pradesh, Arunachal Pradesh -791 112, Email: rpsharma@nitap.ac.in) : Time-dependent oscillatory MHD flow over a porous vertical sheet with heat source and chemical reaction effects. Indian J Pure Appl Phys 2020, 58(12), 877-84.

The current investigation focuses on unsteady, natural convection viscous incompressible, electrically conducting liquid motion over a vertical plane sheet flooded with permeable media with heat source and chemical reaction. A uniform magnetic field is applied in the transverse direction; the liquid augment in the water way determined by identical pressure, the transport of heat is inclined by radiation. The governing equations are solved by applying the perturbation method. The velocity, heat, and mass profiles are shown on graphs for different physical parameters.

9 illus, 3 tables, 12 ref

042544   SHARMA A, SINGH R C, SINGARI R M, BHANDARKAR S L (Mechanical Engineering Dep, Delhi Technological Univ, Delhi-110 042, Email: ranganath@dce.ac.in) : Force and temperature analysis during distinct machining environment using an optimization approach. Indian J Pure Appl Phys 2020, 58(11), 804-11.

Cryogenic cooling with liquid nitrogen has a wide field of scientific and engineering applications. The aim of the presented research work is to analyze the impact on cutting force and temperature during the LN₂ single supply at (i) rake face and double supply (ii) rake and flank face of TiN coated carbide cutting tool during turning of AISI D3 steel. Taguchi based S/N ratio was used for Design of Experiments (DoE) of L₁₈ orthogonal array. The four control factors were selected. The three factors like speed, feed and depth of cut were varied to three levels. The fourth factor was the machining condition which was varied to two levels. The cutting force and temperature were declined by 32-48 % and 34-46 % during the double supply of LN₂ at rake and flank face as compared to single supply at rake face. The influence and percentage of contribution of each factor were found out by Analysis of Variance (ANOVA). The double supply method with LN₂ supply at rake and flank face had the highest effect of contribution in the percentage as 77.13 % and 87.42 % for cutting force and temperature respectively. The values obtained during confirmatory runs were very close to the optimized results within the limits.

5 illus, 5 tables, 23 ref

042542   KUMAR G, KUMAR S (Electronics & Communication Engineering Dep, National Institute of Technology, Delhi-110 040, Email: gkumar3c@gmail.com) : Performance evaluation of a novel dense hybrid passive optical network for acceptable modulation technique using EDFA amplifiers. Indian J Pure Appl Phys 2020, 58(11), 787-94.

Good rating services in terms of high speed data rate, good quality video signal and high speed telecommunication is the prime requirement for the current customers which have resolved in this research work for the first time best of our knowledge for 200 customers with the power amplification from EDFA optical amplifiers. Further, transmission of three play services signals have carried out from different modulation techniques (RZ, NRZ, Manchester, DBPSK and DQPSK modulator) to get the best outcomes. Furthermore, analysis of recommended dense hybrid passive optical network (DHPON) has also done in terms of bit error rate (BER), quality factor (Q-factor), and jitter. Final evaluation has recommended that RZ modulation technique is the acceptable choice to deliver the best services for the customers end.

5 illus, 10 tables, 16 ref

042522   SINGH R, PRASAD D (Electronics & Communication Engineering Dep, Jamia Millia Islamia, New Delhi - 110 025, Email: dprasad@jmi.ac.in) : Novel current-mode universal filter using single FTFNTA. Indian J Pure Appl Phys 2020, 58(8), 599-604.

In this paper, a novel universal filter using single Four Terminal Floating Nullor Transconductance Amplifier (FTFNTA), two capacitors and one/two resistor has been proposed. Sensitivity of pole frequency (ω₀) and quality factor (Q₀) is analysed. Workability of proposed filter has been demonstrated by PSPICE simulations in 0.18µm TSMC CMOS technology.

9 illus, 3 tables, 13 ref

044593   SITHARA S, PRAMADA S K, THAMPI S G (Civil Engineering Dep, National Institute of Technology Calicut, Kozhikode- 673 601, Kerala) : Impact of projected climate change on seawater intrusion on a regional coastal aquifer. J Earth Syst Sci 2020, 129(1), 10.1007/s12040-020-01485-y.

Sea level rise (SLR) is one of the prime consequences of global warming as pointed out by the Intergovernmental Panel on Climate Change (IPCC). SLR adversely affects coastal regions; triggers coastal erosion, inundation, and affects the freshwater–seawater interface as well. This paper presents the results of a study in which a coastal aquifer under changing climate was simulated using a three-dimensional groundwater model. The study area covers a part of the coastal aquifer in Ernakulam district in the State of Kerala, India. Support Vector Machine (SVM) was used for projection of future sea levels under the representative concentration pathways (RCPs) 4.5 and 8.5, based on the projections of Phase 5 of the Coupled Model Intercomparison Project (CMIP5). Both thermosteric and halosteric components were taken into account in the projection of sea level. It was observed that sea level changes are significantly influenced by the halosteric effect. Results indicate that SLR in the year 2050 with respect to the levels in 2014 will be about 8.64 cm and 12.96 cm under RCPs 4.5 and 8.5, respectively. The repercussions of this rise in sea level on seawater intrusion into the coastal aquifer were evaluated by performing simulations with SEAWAT. Results of the study indicate that the effect of this SLR on seawater intrusion is negligible.

40 ref

044591   KAISSASSOU S, LENOUO A, TANESSONG R S, TAMO K, VONDOU A, POKAM W, KANKO J (Electrical and Telecommunication Engineering Dep, Yaoundé Univ, Yaoundé, Cameroon) : Investigation of anomalous propagation conditions in Central and West African stations using high-resolution GPS radiosonde observations. J Earth Syst Sci 2020, 129(1), 10.1007/s12040-020-01477-y.

A comprehensive study on the anomalous propagation (AP) conditions occurring over the central and west African stations was made from 2 years (January 2005–December 2006) high-resolution data measured by GPS (Global Positioning System) radio survey observations. Through data quality control and diagnostic analysis, the probability of AP occurrence and characteristic quantities of the three typical anomalous propagation conditions were given. The sub-refraction, super-refraction and ducting cases were investigated statistically using the vertical profile of modified refractivity gradient. Strong diurnal variation in the percentage occurrence of the AP had its peak during the wet months, while the dry months had the lowest values. From 0600 to 1800 local time (LT) at day (1800–0600 LT at night), the total percentage occurrence of super-refraction, sub-refraction and ducting were 82.5 % (78.5 %), 11% (15.5 %) and 6.5 % (6 %), respectively. Besides statistical results, local meteorological conditions prevailing over central and west Africa have also been discussed.

28 ref

044590   DEEPIKA B V, RAMAKRISHNAIAH C R, NAGANNA S R (Civil Engineering Dep, Shri Madhwa Vadiraja Institute of Technology and Management, Bantakal- 574 115, Udupi) : Spatial variability of ground water quality: A case study of Udupi district, Karnataka State, India. J Earth Syst Sci 2020, 129(1), 10.1007/s12040-020-01471-4.

Groundwater is a reliable source of fresh water for domestic and agricultural water users. It supports subsurface ecosystem by balancing the geo-biological and bio-geochemical processes at micro- and macro-scales of the ecosystem. Overexploitation, anthropogenic activities and improper agricultural practices have contributed to the pollution of groundwater sources all around the globe. The water quality index (WQI) is the most extensively used indicator which transforms the water quality information derived from several parameters into a single value/rating to categorize and provide a general perception of water quality standard. Groundwater quality analysis and mapping via geographical information system (GIS) proves to be beneficial in identifying the locations where the groundwater quality is deteriorating. In the current study, the WQI of groundwater was determined for the samples collected from open and tube wells located within the Udupi district of Karnataka state, India. The groundwater quality parameters such as pH, hardness, calcium, chlorides, nitrates, iron, fluoride, sulfates, manganese, sodium, magnesium, potassium, turbidity, and phosphate were analyzed for water samples collected from 112 randomly chosen open/tube wells in order to determine the WQI. Interpolation approaches such as inverse distance weighting (IDW) and kriging were adopted in the GIS environment to quantify the spatial variability of groundwater quality over the entire geographical area. The groundwater quality maps were generated using the best fit models. The results portray that, the accuracy of interpolation using IDW and kriging methods was dependent on the measures of central tendency and variability of water quality data of different parameters. The kriging interpolation was much accurate for most of the groundwater quality parameters compared to IDW maps. The WQI maps, perhaps signposted the poor quality of groundwater quality in about 1.88 % of the geographical area of Udupi district. Further, about 21.69 % of the area was affected by poor quality of groundwater where suitable strategies for replenishment of groundwater resources should be taken up by the concerned authorities. The spatial distribution maps of groundwater quality aid to locate vulnerable places where immediate action is required.

39 ref

044588   ANAND V, OINAM B, PARIDA B R (Civil Engineering Dep, National Institute of Technology, Manipur) : Uncertainty in hydrological analysis using multi-GCM predictions and multi-parameters under RCP 2.6 and 8.5 scenarios in Manipur River basin, India. J Earth Syst Sci 2020, 129(1), 10.1007/s12040-020-01492-z.

Climate change is likely to have adverse impacts on hydrological processes in a river basin, by altered runoff due to modifications in land use/land cover (LULC) and catchment hydrology. Substantial uncertainty exists to evaluate impacts of climate change on river catchment due to uncertainty in general circulation model (GCM) projections. In this study, impact of climate change on water balance and hydrological regime of Manipur River basin was investigated using SWAT model. A comprehensive semi-distributed soil and water assessment tool (SWAT) was used for future projection of changes in hydrological regime of Manipur River basin based on two representative concentration pathways (RCP 2.6 and RCP 8.5). A coupled model intercomparison project’s (CMIP5) based GCM downscaled outputs and future LULC projected data were used in the analysis. The projected temperature is likely to be increased by 2.84 °C and increase of 836 mm in annual average precipitation is projected under RCP 8.5 by 2090s. Change in meteorological condition and LULC will lead to increase in runoff, evapotranspiration and water yield by 57.79 m³/s (38.32 %), 318.7 mm (54.59 %) and 629.72 mm (89.82 %), respectively, by the end of 21st century. This study demonstrates the importance of water balance components and its spatial and temporal variation in the Manipur River basin. The key findings of this study reveals that the runoff, evapotranspiration and water yield will increase in the coming decades. Increase in water yield may lead to landslides in the hilly region and flooding in low lying areas in future.

47 ref

044582   NENGZOUZAM G, HODAM S, BANDYOPADHYAY A, BHADRA A (Agricultural Engineering Dep, North Eastern Regional Institute of Science and Technology, Nirjuli- 791 109, Arunachal Pradesh) : Spatial and temporal trends in high resolution gridded rainfall data over India. J Earth Syst Sci 2020, 129(1), 10.1007/s12040-020-01494-x.

A high resolution (0.25 °×0.25 °) daily gridded dataset was analysed to study the spatial and temporal trend in various regions of India during the period of 1901–2013. The non-parametric Mann–Kendall (MK) test has been applied to the time series (1901–2013) rainfall data in order to detect the trends for both rainfall depth and number of rainy days. Sen slope estimator test was also used to find out the magnitude of the trend. In addition, Pettitt–Mann–Whitney (PMW) test was employed so as to determine the probable change year. The results of trend analysis of rainfall depth showed maximum number of grid points having increasing trend in summer months, while the dry months showed higher grid points with significant decreasing trend. Jammu and Kashmir, in particular, was found to have increasing trend in all months for all three levels of significances, i.e., 1 %, 5 %, and 10 %, while NE (northeastern) region continuously reported significant decreasing trends. The annual trend analysis of the 30-year moving window of rainfall depth showed higher number of grid points with significant increasing trend during 1901–1950, decreasing trend during 1931–1980, and increasing trend again during 1961–2013. The PMW test for the rainfall depth and number of rainy days for 1901–2010 showed 1961 and 1974 as the most probable change point years with about 339 and 284 grid points agreeing upon it, respectively. The maximum increasing significant trends in rainfall was observed during south-west monsoon months. Recent years also reported an increase in rainfall intensity leading to probable increase of extreme events like floods and droughts.

21 ref

040616   BALAMURUGAN P, VINNILAVU G (Civil Engineering Dep, M.Kumarasamy Coll of Engineering, Karur - 639 113, Email: balamurugan.phd10@gmail.com) : Removal of methyl violet dye from industrial waste water using neem leaf powder. Indian J Ecol 2020, 47(2), 442-5.

The purpose of this study is to remove the dye from the paper mill industry waste water and to use neem leaf powder as an adsorbent. Bath adsorption parameters such as the effect of adsorbent dosage, contact time, agitation speed, pH, are studied. The maximum removal percentage by varying the pH of MV is 80.39 %, The maximum amount of adsorption using neem leaf powder was found to be 0.12 g for MV. Maximum removal percentage of MV is 74.2 %. Freundlich and Langmuir Isotherms were plotted and that concludes neem leaf powder is a good adsorbent for the removal of dye from the waste water.

7 illus, 2 tables, 13 ref

040599   LEBED O, KLYMENKO O, FIZYK L, POTRAVKA L, PICHURA V (Kherson State Agrarian Univ, Ukraine - 73006, Email: pichuravitalii@gmail.com) : Measurement of exhalation of radon-222 from soil of city of Rivne, Ukraine. Indian J Ecol 2020, 47(2), 337-44.

These studies show that the radon content in the air of buildings of Rivne city is mainly influenced by the factors radiological characteristics of the underlying soils under the buildings and building materials (first of all, the radon emanation coefficient in soil, soils gas permeability, etc.). characteristics of the ventilation systems of buildings and modes of ventilation, design features of buildings (number of floors, type of foundation, available aerodynamic connection between floors, location of communication systems within outlines of building, etc.), the type of glazing (the degree of tightness, available ventilation valves, etc.), the type of heating (stove, electric, gas or central) and the level of floor in spaces: basements, semi-basements, first floors regarding land surface. Considering the given factors, can conclude that essential reduction in radon content in indoor air of buildings can be achieved by) choosing a site for building, where radon release from soil is low, applying building envelopes that effectively prevent entering of radon from the soil into building, removing of radon from indoor air. In order to comply with these requirements it is necessary to monitor radiation safety parameters according to volumetric activity in indoor air and radon flux density (RDF) from soil under buildings. The results thereof should be used for sanitary and epidemiological assessment of land sites for building and environmental safety in living spaces. We consider that the main parameter of the anti-radon pre-design stage of construction is the determination of RDF from soil in building site and mapping of RDF from soil in modern cities will allow to develop plans for ecological building and ensure reduction of the ecological radon risk for the citizens. Mapping is based on the analysis of the spatial distribution of values of radon flux density, which is released from surface of city soils. Such approach allows to use the map in urban planning, in pre-design surveys for building, in hygiene studies, for estimating of the doses that are received by citizens due to radon exposure and, finally, as a resource for informing the citizens.

6 illus, 4 tables, 47 ref

044499   CANER Y, SHAKHNOZAKHAN T, ALLAH B (Agricutlural Genetic Engineering Dep, Nigde Omer Halisdemir Univ, Nigde- 51240, Turkey, Email: abthebest@gmail.com) : Apprehending the potential of baby boom transcription factors to mitigate cotton regeneration and transformation. J Cotton Res 2020, 3, 10.1186/s42397-.

Since the advent of transgenic technology, the incorporation of gene(s) encoding traits of economic importance in cotton is being practiced worldwide. However, factors like recalcitrant nature of cotton cultivars, in vitro regeneration via tissue culture (especially via somatic embryogenesis), genotype dependency, long and toilsome protocols impede the pace of development of transgenic cotton. Besides that, types and age of explants, media composition, plant growth regulators and other environmental factors affect in vitro cotton regeneration significantly. The studies of genetic control of in vitro regeneration in plants have elucidated the role of certain transcription factor genes that are induced and expressed during somatic embryogenesis. Among these transcription factors, BABY BOOM (BBM) plays a very important role in signal transduction pathway, leading to cell differentiation and somatic embryos formation. The role of BBM has been established in plant cell proliferation, growth and development even without exogenous growth regulators. This review intends to provide an informative summary of regeneration and transformation problems in cotton and the latest developments in utilization of BBM transcription factors in cotton. We believe that the use of BBM will not only ease cotton genetic improvement but will also accelerate cotton breeding programmes.

3 illus, 1 table, 142 ref

040490   GAUTAM N B, KATE G U, CHAURASIA A S (Chemical Engineering Dep, Visvesvaraya National Institute of Technology, Nagpur - 440 010, Maharashtra, Email: aschaurasia@che.vnit.ac.in) : Production of amorphous silica and activated carbon from rice husk char obtained from two stage gasification process. Indian J Chem Technol 2020, 27(4), 340-5.

In this study the rice husk has been subjected to two-stage gasification to obtain syngas, tar and char. The rice husk char is subjected to alkaline extraction to obtain amorphous silica and activated carbon. The products have been characterized by methods such as BET, FTIR and XRF. The silica obtained from acid leached rice husk has BET specific surface area of 311.68 m²/g and purity of 88.85 %. The BET specific surface area of activated char increase from 102.49 m²/g to 567.03 m²/g after the activation process. The silica extraction using carbon dioxide (CO₂) precipitation is found to be more profitable than acid precipitation.

3 illus, 4 tables, 18 ref

044420   DAYO-ODUKOYA O, WUPPULUR B (Chemical and Biological Engineering Dep, The Univ of Sheffield, Sheffield S1 4AA, United Kingdom, Email: omololad95@gmail.com) : Cell-free production of recombinant proteins. J Biol Engg Res & Rev 2020, 7(2), 10-8.

Cell-free production systems have gained much attention in the last decade due to a quest by researchers to develop more complex and potentially viable proteins, which are otherwise ‘toxic’ or ‘difficult-to-express’ for conventional cell-based systems. Conventional cell-based systems have presented scientist with several other limitations, thereby impeding not only the production but also, the optimization of already expressed proteins both on the bench and large scale. Novel recombinant proteins are believed to be the next generation of products that will transform many fields, especially for therapeutics and diagnostics in medicine. Gleaning from the massive impact of the growth and improvement of penicillin, it is not difficult to see the grave importance of optimizing present processes to be more time and cost efficient. Cell-free protein expression systems (CFPES) already show promising potentials in the development of a wide range of areas that they are already being applied to. The development of high-throughput screening processes, production of integral membrane proteins and difficult to express proteins, are a few key applications to watch out for. It’s numerous advantages, such as flexibility, ease of manipulation, cost and time efficiency to mention a few, make it an even more exciting prospect over the long-standing and ever praised E. Coli and Chinese Hamster Ovary (CHO) whole expression systems. This review succinctly presents the concept of cell-free production as a choice system for recombinant protein, highlighting, many recent applications, advantages and prospects. It also sets out to describe methods of recombinant production using cell-free extracts, while still touching on its presenting limitations.

3 illus, 1 table, 59 ref

040360   SAHOO S S, TRIPATHI P M, CHATTERJEE K (Electrical Engineering Dep, Indian Institute of Technology (ISM), Dhanbad - 826 004, Email: subhendu331@gmail.com) : Low-cost non-superconducting dc-fault current limiter for the enhancement of low-voltage ride through capability of doubly fed induction generator. IETE Tech Rev 2020, 37(4), 418–37.

The wind generation system shares a significant portion of power to the grid, hence, it is necessary for the wind systems to remain coupled to the grid under any circumstances. Earlier wind systems were permissible to detach under any disorders and protection issues. Nonetheless, the disconnection of the wind system affects the stability of the entire grid. In order to overcome those issues, some ride-through schemes should be implemented. The objective of the proposed paper is to provide an effective ride through a scheme with lower cost for doubly fed induction generator based wind energy conversion system. The proposed method includes a non-superconducting DC fault current limiter placed in between the rotor side converter and grid side converter, which effectively restricts the rotor over current, stator over current, DC link voltage, and electromagnetic torque within their safety limit. The effectiveness of the paper is revealed by comparing the result obtained using three phase resistive-super conducting fault current limiter with the conventional vector control scheme. Also, the proposed method is predicated to be cost effective than other FRT techniques.

23 illus, 3 tables, 40 ref

040357   MEHTA H, KAUR H (Electronic Science, Delhi Univ, South Campus, New Delhi 110 021, Email: harsupreetkaur@gmail.com) : Superior performance and reliability of double gate gaussian doped negative capacitance junctionless transistor for 200–500 K. IETE Tech Rev 2020, 37(4), 391–401.

In this work, performance of Double Gate Gaussian Doped Negative Capacitance Junctionless Transistor (DGGDNCJLT) has been studied for temperature range 200–500 K to explore the suitability of the device for applications which demand operation at extended temperature range. The device behavior has been studied by using temperature dependent Landau parameters of ferroelectric material doped hafnium oxide with standard TCAD models. Further, to achieve improved device performance over a wide temperature range, ferroelectric material parameters have been optimized to enhance the impact of negative capacitance effect which consequently improves device characteristics. It has been demonstrated that even for a wide temperature range 200–500 K, DGGDNCJLT exhibits substantial improvement in gate controllability, I_ON/I_OFF ratio, subthreshold swing values less than 60 mV/dec and enhanced current drivability for optimized ferroelectric parameters.

10 illus, 38 ref

040355   BARDIYA S, VASUKI B (Instrumentation and Control Engineering Dep, National Institute of Technology, Tiruchirappalli - 620 015, Email: siddharth.bardiya24@gmail.com) : Performance enhancement of capacitance-type level measurement system using CCII-based interface. IETE Tech Rev 2020, 37(4), 365–76.

In this paper, a simple design of a short-range non-inductive capacitance-type level sensor which is developed for closed tanks (like fuel tanks of vehicles) is proposed. The level sensor is analytically and experimentally verified for measuring the level of non-conducting liquids. Second-generation current conveyor (CCII) based interface circuit is used to measure the capacitance of the level sensor which gives output in the form of frequency. The developed capacitance-based level measurement system is simple in design, low-cost and it is found that the error in the measurement of a level is very small in the range of 0.04 % for a non-conducting liquid level from 10 to 145 mm of the sensor length.

17 illus, 5 tables, 23 ref

040354   ASHA C S, NARASIMHADHAN A V (Electronics and Communication Dep, National Institute of Technology Karnataka, Mangalore, Karnataka - 575 025, Email: asha.cs@rediffmail.com) : A comparative study of illumination invariant techniques in video tracking perspective. IETE Tech Rev 2020, 37(4), 353–64.

Object tracking is being utilized in the field of computer vision over decades for video surveillance, human–computer interaction and robotic applications. Even though the state-of-the-art tracking technology is rapidly growing, few issues are still challenging such as illumination variation, pose variation, scale changes, occlusion, etc. Among these challenges, sudden illumination variation is more complicated which is not solved completely. Most of the current trackers, indeed work under controlled illumination conditions in outdoor and indoor environments. In this work, we study the effect of adding the photometric normalization techniques prior to tracking in order to minimize the drift during abrupt light changes of the median flow tracker (MFT). The tracker under investigation is based on the optical flow method and achieved remarkable results in the tracking literature. However, it drifts off during sudden illumination variation. To resolve this problem, pre-processing technique is incorporated just before tracking. Hence, we present an experimental study of various pre-processing techniques to improve the accuracy of the MFT. A total of eight state-of-the-art normalization techniques are summarized and tested in video tracking perspective. The experiments are carried out with the video sequences obtained from the object tracking benchmark dataset posing sudden illumination change as a challenge to analyze the modified tracker. A comparative analysis indicates that the modified tracker outperforms the baseline tracker in terms of precision score and overlap score.

13 illus, 32 ref

040349   KUMAR A, DAS A, PANIGRAHI R K (Electronics and Communication Engineering Dep, Indian Institute of Technology, Roorkee, Uttarakhand - 247 667, Email: ajeet.kumar.in@ieee.org) : Hybrid-pol decomposition methods: A comparative evaluation and a new entropy-based approach. IETE Tech Rev 2020, 37(3), 296–308.

The analysis of hybrid-polarimetric synthetic aperture radar (hybrid-pol SAR) data can be carried out using two different types of analytical approaches. The first approach is by implementing directtechnique (DT), which directly takes hybrid-pol Stokes parameters as input. The second approach is reconstruction-based-technique (RBT), where the pseudo quad-polarimetric (quad-pol) data is reconstructed from the hybrid-pol measurements. Methods under DT and RBT categories have their own strengths and weaknesses, which are thoroughly investigated in this paper. Also, a comparative analysis of these methods is carried out on the basis of their ability for scattering type discrimination and land-cover classification using synthesized as well as true hybrid-pol data. Moreover, a new entropy (H)-based RBT approach is proposed in this paper which is being compared with the state-of-the-art techniques.

4 illus, 3 tables, 59 ref

040345   PATRO K A K, ACHARYA B, NATH V (Electronics and Telecommunication Engineering Dep, National Institute of Technology Raipur, Raipur, Chhattisgarh, Email: bacharya.etc@nitrr.ac.in) : Secure, lossless, and noise-resistive image encryption using chaos, hyper-chaos, and DNA sequence operation. IETE Tech Rev 2020, 37(3), 223–45.

This paper proposes an image encryption scheme using the combination of chaos, hyper-chaos, and DNA sequence operation. The proposed scheme performs three stages of encryption operations. Those are selection-level hyper-chaotic sequence based DNA-shuffling operation, key-image based DNA-diffusion operation, and hyper-chaotic sequence based DNA-shuffling operation. The advantages of this scheme are higher key space, higher confusion or randomness of pixels, higher sensitivity to the keys and plaintext pixels, stronger resistivity to the noises, and lossless encryption and decryption. Moreover, selection-level hyper-chaotic sequence based DNA-shuffling operation generates more complexities in the confusion process which increases the strength of encryptions and decryptions. The computer simulation and security analyses confirm the good encryption results of the proposed scheme and strong resistivity to the commonly used attacks.

6 illus, 28 tables, 58 ref

040347   SARKAR D, KUMAR A, SADHU P K (Electrical Engineering Dep, Indian Institute of Technology (Indian School of Mines), Dhanbad - 826 004, Jharkhand, Email: debayansarkar92@gmail.com) : A survey on development and recent trends of renewable energy generation from BIPV systems. IETE Tech Rev 2020, 37(3), 258–80.

The electricity demand of the world is growing at a rapid pace. On the other hand, pollution levels due to conventional power generating techniques are drastically increasing and resulting in harmful environmental issues and impacts. As an alternative to this, renewable or clean energy generation from solar photovoltaic’s (PV) in large scale grid connected systems is being increasingly encouraged at the present time. One of the emerging trends in solar PV module power generation is building integrated photovoltaic (BIPV) systems. It meets the local load demands of the building or residential systems and can be used as a stand-alone or on-grid connected system. This paper briefs about the development and recent trends related to renewable energy generation from BIPV systems and its maximum power generation techniques. It also describes both the current-voltage (I-V) and powervoltage (P-V) characteristics of various BIPV products at dissimilar values of solar irradiation. With BIPV, the building or residential components like the roof, an outer wall, window glass, etc., are replaced by PV array module and hence a dual purpose is served with a reduction in the overall cost.

9 illus, 7 tables, 124 ref

040351   HOODA N, KUMAR N (Biomedical Instrumentation Dep, CSIR-Central Scientific Instruments Organisation, Chandigarh - 160 030, Email: getneha.hooda@gmail.com) : Cognitive imagery classification of EEG signals using CSP-based feature selection method. IETE Tech Rev 2020, 37(3), 315–26.

This paper presents a novel approach of spectral feature selection using spatial filters for the classification of four cognitive imagery tasks. The input dataset consists of electroencephalogram (EEG) signals acquired through a commercial wireless headset. The spectral features included mel frequency (MF) components extracted from the low frequency bands of EEG signal. A spatial projection filter was used for the selection of the most relevant features before classification. The popular method of multiclass common spatial pattern (CSP) and regularized CSP (RCSP) are investigated for a subject dependent (intra) and subject independent (inter) generation of spatial projection filter, respectively. Based upon this, present study used two different algorithmic approaches namely MFCSP and MF-RCSP. The developed algorithm successfully classified four imagery actions with the reported prediction accuracy of 46.23 % and 64.01 % and standard deviation of 11.60 % and 8.67 % for MF-CSP and MF-RCSP, respectively.

6 illus, 3 tables, 72 ref

040344   SUBRAHMANYAM K V, KUMAR K K, REDDY N N (VSSC, Trivandrum - 695 022, Email: kvsm2k@gmail.com) : New insights into the convective system characteristics over the Indian summer monsoon region using space-based passive and active remote sensing techniques†. IETE Tech Rev 2020, 37(2), 211–9.

The characteristics of convective systems over the Indian summer monsoon (ISM) region derived by using a unique combination of four satellites METEOSAT, TRMM, COSMIC and CloudSat comprising of both active and passive remote sensing sensors are discussed for the first time. Six years of observations during ISM brought out the preferential geographical regions and time for formation of shallow, deep, and very deep convective systems. It has been observed that shallow, deep, and very deep convective clouds are abundant over ISM region and their distributions show a relatively high frequency of occurrence over the Head Bay of Bengal as compared to other regions. The mean vertical structure of clouds are also been studied using CloudSat observations over several latitudinal belts. The time of maximum occurrence of convective type cloud systems are also quantified using the present observations. The analysis suggests that the deep and very deep convective cloud systems peak during late afternoon hours over many parts of the Indian landmass with few exceptions such as over foothills of the Himalayas, where it peaks during the early morning hours. The three-dimensional structures of convective systems are also discussed. The significance of the present results lie in providing new insights into the characteristics of convective systems by investigating CAPE, clouds, and precipitation, which in turn play a vital role in understanding the internal dynamics of ISM.

6 illus, 30 ref

040341   SINGH A K, PATHAK M K (Electrical and Instrumentation Engineering Dep, Thapar Institute of Engineering and Technology, Patiala - 147 004, Email: ankitee04@gmail.com) : An efficient single-stage based power electronic interface for plug-in electric vehicles. IETE Tech Rev 2020, 37(2), 169–79.

In this research, a new power converter has been presented for plug-in electric vehicle applications, which is derived from the conventional secondary ended primary inductance converter (SEPIC). The proposed converter operates for all modes of vehicles [plug-in charging mode (PCM), propulsion mode (PM) and regenerative braking mode (RBM)] with high voltage conversion ratio. The proposed structure operates as a SEPIC in PCM and as a conventional single switch buck/boost converter in PM and RBM. Therefore, universal voltage range, i.e., 85–265 V can be used to charge the battery as well as dc-link voltage can be varied in wide range. A comparative study of the proposed converter has been investigated with existing integrated converters. Furthermore, an analytical loss analysis of the semiconductor devices has been investigated to select the power stage switches as well as efficiency calculation of the converter in each mode. The proposed concept is validated through strong simulation and hardware results.

14 illus, 4 tables, 18 ref

040338   KUMAR A, SAHU P R (Electronics and Communication Engineering Dep, PDPM–IIITDM Jabalpur, Jabalpur - 482 005, Email: atul.kumar@iiitdmj.ac.in) : Performance analysis of DCSK-BDR systems over nakagami-m fading channels. IETE Tech Rev 2020, 37(2), 137–46.

In this paper, a differential chaos shift keying bidirectional relaying (DCSK-BDR) scheme is proposed in which two source nodes exchange their information through a relay node. By using network coding at the relay, the proposed scheme offers spectrum and energy efficiency over the conventional DCSK transmission scheme for end-to-end communication. Analytical expressions for the probability density function (PDF) of the signal-to-noise ratio (SNR) of each hop are derived for Nakagami-m fading channel. The end-to-end average bit error rate (BER) of the system is evaluated. Throughput of the proposed schemes is also presented and compared. Numerical results are verified with the simulation results and plotted for different parameters.

10 illus, 44 ref

040335   GUPTA A, GANGWAR R K (Electronics & Telecommunication Dep, National Institute of Technology, Raipur, Chhattisgarh - 492 010, Email: agupta.etc@nitrr.ac.in) : Hybrid rectangular dielectric resonator antenna for multiband applications. IETE Tech Rev 2020, 37(1), 83–90.

This article examines the triple-band rectangular dielectric resonator antenna (RDRA) excited with novel composite feeding structure (combination of inverted H-shaped monopole and vertical strip). Three attractive features of proposed design are as follows: (i) composite feeding structure creates dual higher order modes in RDRA (i.e., TE^x_δ,2,1 and TE^x_δ,4,1); (ii) triple-band characteristic is achieved with the help of hybrid antenna concept; and (iii) adjacent bands with higher order modes have been merged to enhance the bandwidth. Simulated outcomes have been practically confirmed with the help of developed prototype of proposed antenna. The proposed RDRA is operated over three frequency bands, i.e., 1.45–1.63 GHz, 3.62–4.1 GHz, and 4.55–5.86 GHz. The proposed design is quite suitable for WLAN (5.2/5.8 GHz), WiMAX (5.5 GHz), AMSAT (5.6 GHz), GPS (1.57–1.58 GHz), point-topoint microwave, and telemetry in the USA (4.44–4.99 GHz).

9 illus, 3 tables, 18 ref

040333   SINGH A, NAIK K K, KUMAR C R S (Electronics Engineering Dep, Defence Institute of Advanced Technology, Pune - 411 025, Email: ajit_pee13@diat.ac.in) : NOMURA: A spectrally efficient non-orthogonal 5g multiple access downlink scheme for cognitive radio. IETE Tech Rev 2020, 37(1), 56–65.

Orthogonal Frequency Division Multiple Access (OFDMA) is now becoming an impeding rather than a sustainable technology for realizing the vision of 5G due to its tight synchronization, orthogonality constraints, and significant bandwidth wastage due to Cyclic Prefix. To overcome this limitation, several non-orthogonal schemes have been introduced as candidates for upcoming 5G technology for providing flexible, reliable, fair and high-speed multiple access to users and/or devices. A combination of Non-Orthogonal Multiple Access (NOMA) and Universal Filtered Multi-Carrier (UFMC) is found suitable for downlink scenario. We propose NOMA-UFMC-based Radio Access (NOMURA) scheme, which is asynchronous, bandwidth efficient and provides higher throughput. The proposed scheme is non-orthogonal in two aspects: (1) NOMA provides resources to different users via power scaling while utilizing same frequency resources, and (2) UFMC allows for a slight delay in synchronization, hence not strictly compliant with orthogonality requirements. The components of the proposed scheme, namely NOMA and UFMC, are backward compatible with OFDMA ensuring trivial application of Multiple Input Multiple Output and other performance enhancement measures already developed for OFDMA. We provide simulation results benchmarked against OFDMA and Filter Bank Multi-Carrier-Filtered Multi-Tone and show that NOMURA is more apt for flexible bandwidth allocations, active cancellation, higher throughput and provides equivalent Bit Error Rate performance under AWGN and Rayleigh fading conditions.

9 illus, 1 table, 27 ref

040332   SHARMA D, PRAJAPATI Y K, TRIPATHI R (Electronics and Communication Engineering Dep, Motilal Nehru National Institute of Technology, Allahabad - 211 004, Email: yogendrapra@gmail.com) : Success journey of coherent PM-QPSK technique with its variants: A survey. IETE Tech Rev 2020, 37(1), 36–55.

Nowadays, public demands high capacity global internet traffic in terms of cloud computing, video gaming, fiber to the home and mobile networks, etc. To fulfill such huge traffic requirement, high-speed digital coherent transmission system came into the picture. Polarization multiplexedquadrature phase shift keying (PM-QPSK) technique is an emerged praiseworthy digital coherent optical multiplexing technology. PM-QPSK provides efficient bandwidth to fulfill the high traffic demands by availing enormous potential bandwidth of optical fiber. PM-QPSK is a good hybrid multiplexed candidate in terms of delivering high optimized receiver sensitivity and spectral efficiency with appreciable reach. In this survey, we present a state of art over different strategies employing PM-QPSK techniques to achieve an enhancement in various optical performance parameters. During the survey, various research challenges are encountered, which are also presented with various future prospects.

7 illus, 10 tables, 101 ref

040326   BHARATHI A, MERUGU L, RAO P V D S (ECE Dep, Osmania Univ, Hyderabad, Telangana, Email: bharathig8@gmail.com) : Reconfigurable corner truncated square microstrip patch antennas for wireless communication applications. IETE J Res 2020, 66(2), 242–55.

Reconfigurability of the radiation characteristic is one of the recent significant developments associated with the characterization of microstrip patch antennas for wireless communication systems. This paper presents, in an exhaustive and comprehensive form, the recent results for various novel reconfigurable microstrip antenna topologies involving corner truncations and ring slot loading, coupled with PIN diode switching mechanism. These designs exhibit the functions of polarization reconfiguration, polarization, and frequency reconfiguration with an attractive single layer patch and easily realizable practical structure. Emphasis is placed on design, simulation, and experimental results of each of the proposed geometries illustrating the antenna versatility in several applications.

20 illus, 4 tables, 22 ref

040325   SUJANA J A J, REVATHI T, RAJANAYAGAM S J (Mepco Schlenk Engineering Coll, Sivakasi, Tamilnadu, Email: ang_jenefa@mepcoeng.ac.in) : Fuzzy-based security-driven optimistic scheduling of scientific workflows in cloud computing. IETE J Res 2020, 66(2), 224–41.

Cloud computing is a new computing paradigm which is gaining wide acceptance among scientific fraternity in the recent years. The services of cloud could be effectively used for running large-scale data and computation-intensive scientific workflow applications. Finding the optimal schedule for such workflows has been a major concern among the cloud users. In the present work, a novel approach of combining both optimization of the schedule along with the allocation of the virtual machines (VMs) based on security requirements is envisaged. This paper focuses on generating an optimized schedule for the complex workflow structures. The main objective of the schedule is to minimize the makespan of the schedule. In this paper, we design the scheduling heuristic based on the cost prediction matrix (CPM) for optimized cost calculation. The CPM will estimate the execution cost by considering the child’s child task also. This leads to a prophetic estimation on the available VMs. In addition to this, we have used a fuzzy-based decision model for deciding the selection of the VMs based on security constraints in the cloud. This fuzzy model is combined with the optimized cost calculation from CPM for each and every task of the workflow. The proposed secured cost prediction-based scheduling (SCPS) algorithm then schedules the task in the best possible VM, so that the makespan is minimized. Our results show that the newly developed SCPS algorithm yields efficient schedule compared to other existing scheduling models in spite of the inclusion of security constraints besides scheduling. Nevertheless, this secured scheduling is done without much increase in the time complexity.

16 illus, 9 tables, 42 ref

040323   ABID A, MALIK T N, ABID F, SAJJAD I A (Electrical Engineering Dep, Engineering and Technology Univ, Taxila, Pakistan, Email: anumabid24@gmail.com) : Dynamic economic dispatch incorporating photovoltaic and wind generation using hybrid FPA with SQP. IETE J Res 2020, 66(2), 204–13.

This paper presents a hybrid approach to explore the effect of wind and photovoltaic energy on conventional power network using dynamic economic dispatch. This model deals with stochastic and unpredictable character of wind and solar power output while considering the gaps between the real and predicted output power. A hybrid flower pollination algorithm with sequential quadratic programming is applied to reduce the overall operating costs of generators, while allocating generation to the committed units. The proposed technique is applied on power system having 13 solar units and a wind plant connected with 3, 5, and 10 generating units, respectively. The results of algorithm simulations performed in MATLAB 2014b confirm the competence of the suggested method.

5 illus, 6 tables, 24 ref

040322   SHIVAM, DAHIYA R (Electrical Engineering Dep, National Institute of Technology Kurukshetra, Kurukshetra, Haryana - 136 119, Email: shivam55ram@gmail.com) : Distributed control for DC microgrid based on optimized droop parameters. IETE J Res 2020, 66(2), 192–203.

The droop control approach is widely used in case of parallel operation of DC sources. The conventional droop control method is realized by linearly reducing the load voltage as the load current increases. This droop control is unable to achieve effective equal load sharing as well as the bus voltage regulation. The load sharing error is enhanced when cable line parameters of parallelconnected DC sources are not equal. The droop gain and nominal voltage reference of source converters are the key parameters to achieve the bus voltage deviation within the permissible limits and effective load sharing. In this paper, the droop parameters of the proposed distributed control scheme are optimized with the help of the Particle Swarm Optimization technique for the aforementioned control objectives of the DC microgrid for unequal cable line resistances. The performance of the proposed control scheme based on optimal droop parameters is verified through MATLAB/Simulink environment and validated by a hardware-in-the-loop real-time simulator based on the dSPACE 1202 platform.

13 illus, 6 tables, 34 ref

040321   SINGH A (Electronics Dep, NSIT, New Delhi-110 075, Email: engganuradhasingh@gmail.com) : Design and analysis of memristor-based combinational circuits. IETE J Res 2020, 66(2), 182–91.

This paper presents a novel memristor-based combinational circuit, namely: 4:2 priority encoders, 2:4 decoder, and BCD to EX-3 code converter. The performance of all these logic circuits is analyzed with respect to equivalent CMOS. The proposed work extends the philosophy of designing gate level circuit and then using the basic gate design to implement the combinational circuit. Memristor gates are used to implement the desired logic function. In the proposed work, memristor-based novel XOR gate is designed. This gate is then utilized to implement the encoder, decoder, and BCD to EX-3 code converter circuits. The proposed circuits have the advantage like low transistor count, high speed, and low power. The simulation is carried out in LTSPICE.

9 illus, 6 tables, 17 ref