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Recently, a 206.5[Formula: see text]MHz Stratosphere Troposphere (ST) Radar system was successfully installed and made operationalized at Aryabhatta Research Institute of Observational Sciences (ARIES) (29.4N, 79.2E, 1793[Formula: see text]m amsl), Nainital, India. It is the first such unique observational facility located in the central Himalayan region and will play an important role in understanding the meteorological conditions of the region that has a vital role in atmospheric studies in South Asia. The entire ST radar system is indigenously built and installed in a compact 30[Formula: see text][Formula: see text][Formula: see text]m two-storey building, making maximum use of the available space in the hilly terrain. A metal fence of 3.5–4[Formula: see text]m height was designed and installed along the perimeter of the array to attenuate the clutter returns from the nearby mountains with the shielding efficiency 22–25[Formula: see text]dB. Since its operation, the radar has obtained useful data of neutral atmosphere, precipitation, convection, and hailstorm events for scientific research. The technical details of different sub-systems, radar integration and calibration methodology are presented here. A dedicated off-line GUI based data processing tool has been developed and is being used for the data analysis. A comparison of wind components derived from ARIES ST Radar with collocated GPS-radiosonde observations indicates a good agreement with correlation coefficients for zonal (0.92), meridional (0.76), wind speed (0.86), and wind direction (0.7). The change in wind patterns is demonstrated up to a height of about 31[Formula: see text]km amsl and the tropopause was marked to be at 16–17[Formula: see text]km on 2020 June 20. A dramatic reversal of winds from westerly (below the tropopause) to easterly (above the tropopause) was also observed. ARIES ST Radar could capture the signature of the precipitation in addition to neutral air in the same Doppler spectrum and the height of the starting point of precipitation is identified to be [Formula: see text][Formula: see text]km. This ability to detect atmospheric scattering from both neutral wind (Bragg) and precipitation (Rayleigh) in the same spectrum makes the 200[Formula: see text]MHz band radar a unique instrument in the wind profiler application for atmospheric research.

Optical turbulence in the atmosphere is a key factor which governs the sharpness of images produced from ground-based optical telescopes. The intensity of optical turbulence can be conveniently assessed by the estimation of the refractive index structure constant ([Formula: see text]). Here, observations from a stratosphere troposphere radar (206.5[Formula: see text]MHz) that is co-located with the optical telescope facilities in the central Himalayas, are used for the estimation of [Formula: see text]. The integrated profile of [Formula: see text] and winds over about 2–20[Formula: see text]km have been used to estimate seasonal and diurnal variation of “seeing”, wavefront coherence time, isoplanatic angle and scintillation rate. The mean [Formula: see text] over the site varies from 10[Formula: see text] to 10[Formula: see text][Formula: see text]m[Formula: see text] with the largest values in the monsoon and post-monsoon season. The best “seeing” conditions are observed in the winter and post-monsoon season with median “seeing” varying from 0.39[Formula: see text] to 0.81[Formula: see text]. The largest contribution to the diurnal variation of “seeing” comes from turbulences at 2–5[Formula: see text]km height region. A weak correlation of diurnal variation of “seeing” has been observed with surface temperature and relative humidity (RH). Among astroclimatic parameters, the largest isoplanatic angle is associated with winter season with median value of 2.57[Formula: see text] and wavefront coherence time of [Formula: see text]4.2[Formula: see text]ms. The least scintillation in intensity is observed in the winter season with a rate of [Formula: see text]10% and most in monsoon season with [Formula: see text]45% rate. This study is expected to have a positive impact on the optimization of the operation of adaptive optical techniques, observing time and scheduling of scientific programmes for optical telescope facilities in this region of the central Himalayas.

The primary concerns in the practical photovoltaic (PV) system are the power reduction due to the change in operating conditions, such as the temperature or irradiance, the high computation burden due to the modern maximum power point tracking (MPPT) mechanisms, and to maximize the PV array output during the rapid change in weather conditions. The conventional perturb and observe (P&O) technique is preferred in most of the PV systems. Nevertheless, it undergoes false tracking of maximum power point (MPP) during the rapid change in solar insolation due to the wrong decision in the duty cycle. To avoid the computational burden and drift effect, this article presents a simple and enhanced P&O MPPT technique. The proposed technique is enhanced by including the change in current (dI), in addition to the changes in output voltage and output power of the PV module. The effect of including the dI profile with the traditional method is explained with the fixed and variable step-size methods. The mathematical expression for the drift-free condition is derived. The traditional boost converter is considered for validating the effectiveness of the proposed methods by employing the direct duty cycle technique.

This article describes the origin and development of the radio astronomy group of Tata Institute of Fundamental Research (TIFR), which later became the National Centre for Radio Astrophysics in Pune in 1991, under the leadership and guidance of Govind Swarup over the past 50 years. The innovativeness of the designs and the indigenous development of the large radio telescopes by a team of young scientists and engineers are highlighted. The scientific results from the work of the group are briefly summarized.

In facial expression recognition applications, the classification accuracy decreases because of the blur, illumination and localization problems in images. Therefore, a robust emotion recognition technique is needed. In this work, a Multi-scale and Rotation-Invariant Phase Pattern (MRIPP) is proposed. The MRIPP extracts the features from facial images, and the extracted patterns are blur-insensitive, rotation-invariant and robust. The performance of classification algorithms like Fisher faces, Support Vector Machine (SVM), Extreme Learning Machine (ELM), Convolutional Neural Network (CNN) and Deep Neural Network (DNN) are analyzed. In order to reduce the time for classification, an OPTICS-based pre-processing of the features is proposed that creates a non-redundant and compressed training set to classify the test set. Ten-fold cross validation is used in experimental analysis and the performance metric classification accuracy is used. The proposed approach has been evaluated with six datasets Japanese Female Facial Expression (JAFFE), Cohn Kanade (CK +), Multi- media Understanding Group (MUG), Static Facial Expressions in the Wild (SFEW), Oulu-Chinese Academy of Science, Institute of Automation (Oulu-CASIA) and Man–Machine Interaction (MMI) datasets to meet a classification accuracy of 98.2%, 97.5%, 95.6%, 35.5%, 87.7% and 82.4% for seven class emotion detection using a stack of Restricted Boltzmann Machines(RBM), which is high when compared to other latest methods.

The present study illustrates the efficiency of microalgae based treatment system. Treatment of wastewater with microalgae based system have the ability of remove the nutrients( nitrogen , phosphorus and other nutrients ) , heavy metals ,toxic substance (both organic and inorganic) , BOD ,COD and other impurities present in the waste water by using the sunlight, co2 and impurities like nutrients present in the wastewater. The microalgae also have the ability of the fix the excess carbon dioxide present in the environment and release the oxygen and solve the problem of global warming .According to the various study the nutrients removal efficiency of 78- 99% of nitrogen and phosphorus the treatment system also succeed to removal of the 40-65%of COD , BOD and other impurities present in wastewater. The organic and inorganic substance released into the environment as a result of domestic, agricultural and industrial wastewater. The normal primary & secondary treatment process are involved in the treatment. Present investigation focuses on the bioremediation of waste water using microalgae.

Sport has been used as a core component of programming and in building inclusive social spaces long before it was finally recognized and mainstreamed as a part of the Millennium Development Goals and later in the Sustainable Development Goals. S Ananthakrishnan describes in detail the progressive incorporation of sports in the UN development agenda and discusses the limits and possibilities for member countries like India. The chapter is designed around the issue of sports as a new engine for social development across the globe and its role in empowering the disadvantaged, and its potential for combatting discrimination, engaging youth and women. Until very recently development studies scholars have neglected the rich possibilities of sports as an entry point and a stimulus for change. However, over the decade it has become a strategy for social intervention among disadvantaged communities. The richer countries of the Global North have to be persuaded to invest in sports and its equitable growth in the developing regions, thus defining a new path of international cooperation.

This paper presents a working and Simulation of a four-axis welding robot. The Robotic aspects have many applications in industries including welding. These tasks are described according to the end effector function. This work deals with handling a robotic arm or welding arm by a master manipulator where the end effector is used to hold. For the movement of the robotic arm, a fuzzy logic controller is used, and its performance is compared to that of a PID controller. Forward kinematics deal with the problem of finding end-effector pose (position + orientation) with given joints variables using two methods: Homogeneous transformation and Denavit-Hartenberg Representation. Actuation modes include Torque and Motion which are described through simulation showing effects on working of machine due to dynamics. The model has been done based on MATLAB/Simulink software.

A field study was conducted to assess the effect of macronutrient fertilizer mixtures over the quality parameters and nutrient use efficiency of cotton at Tamil Nadu Agricultural University, Coimbatore. The treatment comprised of fertilizer mixtures of different sources for particular macronutrient (for nitrogen (urea and calcium nitrate), for phosphorus (single superphosphate), for potassium (muriate of potash and sulphate of potash) and for nitrogen and phosphorus (mono ammonium phosphate, di ammonium phosphate and ammonium sulphate phosphate)). It was observed that in cotton, agronomic efficiency was considerably increased due to application of calcium nitrate containing fertilizer mixture (calcium nitrate + di-ammonium phosphate + muriate of potash). No significant difference was recorded in quality parameters of the fiber whereas protein and oil content was increased by the application of sulfur containing fertilizer mixtures (calcium nitrate + di-ammonium phosphate + sulphate of potash and urea + di-ammonium phosphate + sulphate of potash respectively).

Named Data Networking (NDN), an information centric network architecture, aims to provide an efficient and scalable alternative for content distribution. Modern Internet applications have more emphasis on data, and are less concerned about the location from where data is retrieved. NDN’s communication primitives being strictly pull based help in bringing this focus shift from location of data to the data itself. A concern for NDN is to enable the support of other popular communication primitives, such as the Publisher-Subscriber (Pub-Sub) model, seamlessly. The Pub-Sub model is well suited for applications that require periodic retrieval of data or event triggered data, such as in Industrial Automation Control Systems (IACS). This paper presents the design and development of a model to support the group based Pub-Sub communication primitives in ndnSIM, a popular ns-3 based network simulator for NDN. The functionality of the proposed model is tested by developing an end-to-end simulation environment in ndnSIM that is representative of the popular use cases of Pub-Sub communication primitives.

In view of cardiac output monitoring application of impedance cardiography a miniature impedance cardiograph has been developed, which is based on an application specific integrated circuit (analog front end chip AFE4300). Carrier current capability of this chip has been enhanced four times (up to 3.2 milliamperes) for cardiology applications with the help of an external resistance, not provisioned in the original design. Also the sensed signal is externally amplified before feeding to AFE chip to increase resolution in the impedance range of 10-50 Ohms.The AFE chip is interfaced to a Personal Computer with the help of a microcontroller board through a USB cable. Application software programs the AFE chip for sending a carrier current of 3.2 milliamperes (peak to peak) to the subject's body segment through current output ports and sensing the chest impedance through voltage input ports. The chest impedance is read in detector mode and communicated to Laptop through serial peripheral interface of the chip. Chest impedance, change in impedance as a function of time and rate of change of impedance are displayed on the graphic user interface. Fifteen minute data from volunteers have shown consistent recordings, as described in this paper.

Medical diagnosis is the process of determining a patient’s health condition by the observation of symptoms and test results. Cardiovascular diseases are one of the most common causes of death worldwide. Electrocardiogram (ECG) is one of the effective ways for diagnosing heart conditions. ECG records and detects the strength and timing of electrical activity of the heart. A proper diagnosis can reduce mortality rate. Artificial intelligence (AI) has shown its inexplicable contribution in the field of medical science, especially in diagnosis. Convolutional neural network (CNN) is the most popular deep learning algorithm, which captures the relevant features by itself. Deep learning requires a massive amount of data to train the network, which increases the computational complexity. This chapter aims to reduce the computational complexity. We consider the cardiac diseases such as arrhythmia and myocardial infarction (MI) for our experimental analysis. We have used heartbeat segmented and preprocessed ECG data available at Kaggle. We aim to reduce the computational complexity of the existing deep learning architecture for cardiac disease classification by using the feature-extracted data. We propose the single-layer CNN for the classification of ECG beats of arrhythmia and MI. We also evaluated the performance of the proposed model by using the following evaluation metrics: precision, recall, and F1 score. The performance of the proposed architecture is high compared to state-of-the-art methods.

We re-examined solar polar magnetic fields, using ground based synoptic photospheric magnetograms, during solar cycle 24. IThe signed polar magnetic fields showed an unusual hemispheric asymmetry in the polar field reversal process with a single unambigous reversal in the Southern hemisphere around late 2013 while the polar reversal in the Northern hemisphere started earlier around June 2012, but was completed only by the end of 2014. The examination of the unsigned polar magnetic fields in cycle 24 showed a continuing decline of fields in the Northern hemisphere whereas in the Southern hemisphere, it had partially recovered. However, the overall declining trend in solar polar fields, which began in the mid-1990’s, is still in progress. The continued decline seen in solar photospheric fields raises thequestion of whether we are heading towards a Grand or Maunder like solar minimum.

This paper assesses the quality of water using different graphical and statistical methods like Durov, Schoeller, Piper – Tri linear diagram, Box and Whisker plot for three seasons in the study area Alathur block, Perambalur District. The graphical representation provides limitations compared with the multivariate method for large data sets. A total of 10 groundwater samples were collected from hand dug wells in this area and they were analyzed for various physical and chemical parameters. The sequence of the dominance of the major ions are in the following order Na+> Ca2+> Mg2+> K+and Cl-> SO42-> HCO3-> NO3-. The dominating hydrochemicals of facies of groundwater are Ca-Cl and mixed Ca-Mg-Cl and alkaline earth metals (Ca2+, Mg2+) and strong acids (SO42-, Cl-) that dominate over alkalis (Na+, K+) and weak acids like HCO3-, CO3-. Based on the analytical result, groundwater in the study area is generally hard to very hard, slightly alkaline to brackish in nature. This indicates that leaching of salts, rock weathering and evaporation are among the most dominant processes in controlling water quality. For industrial purposes, the quality of water was assessed by using the Langeliner saturation index (LSI) and Ryznar saturation index (RSI). Seasonal variations in different parameters were also determined.

Millions of people depend on the navigation facilities available in smart-phones and web browsers for their daily commutes, planning long trips ahead of time, looking up places etc. Integration of GPS and compass made navigating anywhere in the world a trivial task. Today, there are several applications available that fit the purpose of navigation such as Waze, HereWeGo (previously known as Here Maps by Nokia), Google Maps, etc. When Google Maps was used to embark on a tour that will take us to chosen places by covering the least distance possible, it is observed that none of the aforementioned applications provide such a feature. In this paper, a framework is developed with Google Maps APIs to create such a feature. This problem is mapped to the Traveling salesman problem and tried to solve it using algorithms known for approximating TSP such as Artificial Bee Colony Algorithm, Particle Swarm Optimization and Two-opt Algorithm. The framework is tested with these algorithms and found that, Particle Swarm Optimization gives the best possible route.

Several studies have shown that people with disabilities benefit substantially from access to a means of independent mobility. While the requirements of many individuals with disabilities can be satisfied with manual or powered wheelchairs, a segment of the disabled community finds it difficult or impossible to use wheelchairs independently. This paper presents an autonomous indoor navigation system for wheelchairs based on sign board recognition. The system uses a deep learning model to detect signboards from surroundings and Azure Text Analytics API is used to extract the text from the signboard images. The system runs on a Raspberry Pi minicomputer and can be installed on any powered wheelchair. Experimental results and comparisons prove the efficiency of the proposed system.

We examine the temporal changes in both solar polar magnetic field (PMF) at latitudes $\ge$ $45^{\circ}$ and heliospheric magnetic field (HMF) at 1 AU during solar cycles 21--24 with emphasis on the recent activity changes after July 2015, the so called "mini solar maximum" of cycle 24. While unsigned PMF shows a solar-cycle-like variation in cycles 21 and 22, it shows an anti-solar-cycle-like variation in cycle 24. In addition, the floor level of the HMF (of 4.6 nT), i.e. the value that the HMF returns to at each solar minimum, is breached about two years prior to cycle 24 minimum, indicating a reduced HMF floor level in the upcoming cycle 24 minimum. In light of the change of unsigned PMF and the availability of a revised smoothed sunspot number (SSN) after July 2015, we have revisited the correlation of unsigned PMF and HMF at solar minimum. The correlation is used to estimate a new value of the HMF of 4.16$\pm$0.6 nT at the cycle 24 minimum and the amplitude of the upcoming cycle 25. The updated prediction is 82$\pm$8 and 133$\pm$11, on the original (V1.0) and revised (V2.0) SSN scales, respectively. These better and more reliable SSN values (due to the larger data set) imply that we will witness another mini solar maximum in the upcoming cycle 25 which will be relatively stronger than cycle 24 and a little weaker than cycle 23, even if the current solar cycle minimum occurs in 2021 instead of 2020., Comment: 16 pages, 4 figures, 2 tables

Space electromagnetic and plasma sensor is a proposed space payload consisting of an electric field vector sensor—a tri-axial arrangement of monopoles in a mutually orthogonal configuration—and a magnetic field vector sensor, which is a tri-axial arrangement of mutually perpendicular loop antennas. Both operate between 0.5 and 20 MHz in order to acquire the complete 3D polarization matrix. The antennas, which are meant to be electrically short, are matched with a high input impedance amplifier, followed by gain blocks, filters and a six-channel data acquisition system. Some of the proposed goals of the project include study of the low frequency Sun, plasma interactions between the solar wind and Earth’s magnetosphere, lunar atmosphere, and radio emission from other planets within the solar system. This article describes the construction of a laboratory prototype and preliminary calibration results.

A new polymeric dyad of oligo-anthracene-block-poly(3-hexylthiophene) (Oligo-ANT-b-P3HT) has been synthesized as a donor–donor dyad building block for organic photovoltaics. The polymer dyad and oligomer of anthracene-9,10-diyl (Oligo-ANT) are prepared by Grignard Metathesis. The higher order of crystallinity and molecular chains ordering at solid phase reveal the intrinsic optical and electrical properties of polymeric dyad resulting in relatively higher light harvesting ability compared to the oligo(anthracene-9,10-diyl). The UV-visible spectrum of (Oligo-ANT-b-P3HT) in solution shows broad absorption with two sets of absorption from both anthracene and thiophene core units, covering a wide range of the visible spectrum. The test devices of the blends of polymeric dyad with fullerene C61 (PCBM) show improved photovoltaic performance with a power conversion efficiency of 3.26% upon subjecting to pre-fabrication thermal treatments. With optimized morphology of the interpenetrating network and the shorter fluorescence lifetime of the annealed dyad/PCBM blends, the effective charge transfer from the donor dyad to PCBM has evidenced. Thus, these studies will allow further synthetic advances to make potential high crystalline polymeric dyads with significantly improved light harvesting capability. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 3032–3045

An adaptive position controller is investigated to compensate for the effects of both the actuator and linkage dynamics in a four axis hydraulic robot. A simulation study was done, prior to the experimental implementation, in order to compare and contrast different adaptive control algorithms for this system. The dynamics of the linkage were developed using Lagrangian techniques. The equations of motion of the robot were generated with a computer program which uses symbolic manipulation. The equations describing the dynamics of the hydraulic actuator were developed using a lumped parameter, control volume analysis. Implicit and explicit deterministic autoregressive moving average (DARMA) model based adaptive control algorithms were first simulated for a single axis hy­ draulic servo system. Least-squares identification algorithms with or without covariance resetting or forgetting factors were combined with model reference, pole assignment, and weighted one-step-ahead control algorithms. The model reference adaptive controller which offered an advantage in the design process was then applied to the entire four axis model. Simulation results indicated a satisfactory response for this multiple-input, multiple-output system. The results of this discrete-time, model-reference adaptive controller (MRAC) were compared with Craig's continuous-time, statevariable-based, adaptive con

We report observations of a steady 20 year decline of solar photospheric fields at latitudes ≥45° starting from ∼1995. This prolonged and continuing decline, combined with the fact that cycle 24 is already past its peak, implies that magnetic fields are likely to continue to decline until ∼2020, the expected minimum of the ongoing solar cycle 24. In addition, interplanetary scintillation observations of the inner heliosphere for the period 1983–2013 and in the distance range 0.2–0.8 AU have also shown a similar and steady decline in solar wind microturbulence levels, in sync with the declining photospheric fields. Using the correlation between the polar field and heliospheric magnetic field (HMF) at solar minimum, we have estimated the value of the HMF in 2020 to be 3.9 (±0.6) nT and a floor value of the HMF of ∼3.2 (±0.4) nT. Given this floor value for the HMF, our analysis suggests that the estimated peak sunspot number for solar cycle 25 is likely to be 62 (±12).

Aggregation induced emission enhancement (AIEE) is widely regarded as an efficient tool to offset the problem of aggregation caused quenching (ACQ) in luminogens. The ACQ phenomenon in small organic molecules and polymers is detrimental to the performance of OLEDs. Efficient pure white electroluminescent polymers, obtained by the copolymerization of 9,9-dihexylfluorene as a blue host with (E)-2,7-dibromo-9H-fluoren-9-yl-2-cyano-3-(4-(dimethylamino)phenyl) acrylate (FCP) as a yellow emitting covalent dopant with AIEE properties on the main chain of the copolymers, have been designed and synthesized. White light emission was achieved in copolymer FCP 2.5, which contained 2.5% of the AIEE luminogen. Interestingly the copolymers exhibited an enhanced emission upon aggregation even at low compositions of FCP. The enhanced emission in the copolymers is attributed to the supramolecular assembly of the polymeric chains. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) investigations of the monomer and copolymers of FCP revealed the presence of an intramolecular charge transfer (ICT) transition between dimethylamine and the cyanoacrylic acid unit. OLEDs were fabricated using a device with a ITO/PEDOT:PSS/EML/Al structure. White light emitting diodes were fabricated from FCP 2.5 as the emissive layer (EML) and elicited a white electroluminescence with Commission Internationale de l'Eclairage (CIE) coordinate values of (0.33, 0.34). They exhibited a maximum brightness of nearly 9332 cd m−2, a power efficiency of 4.13 lm W−1 and a luminous efficiency of 6.34 cd A−1. Interestingly, the supramolecular ordering in FCP 2.5 considerably reduces the charge trapping which results in a reproducible white light emission.

Aggregation induced enhanced emission (AIEE) is considered as an important tool to circumvent the aggregation caused quenching (ACQ) effect in organic light emitting diodes (OLEDs). Charge trapping and surplus long wavelength electroluminescence is a cause of concern in single polymer based white OLEDs. However, the potential of luminogens with AIEE property as a credible tool to offset the above problems in white light emitting single polymer is not properly explored. In this study design, synthesis and spectral characterization of a polymerizable luminogen, (2Z,2′Z)-6,6′-(2,7-dibromo-9H-fluorene-9,9-diyl)bis(hexane-6,1-diyl)bis(2-cyano-3-(10-hexyl-10H-phenothiazin-3-yl)acrylate(FCPA) with AIEE property and its copolymers is presented. Lippert-Mataga studies showed that reduced local polarity caused by aliphatic chains in condensed state of FCPA resulted in AIEE property. The copolymers P(FCPA-1) and P(FCPA-0.5) with 1% and 0.5% FCPA moieties showed white electroluminescence and enhanced thin film photol...

Aerial and ground robots have been widely used in tandem to overcome the limitations of the individual systems, such as short run time and limited field of view. Several strategies have been proposed for this collaboration and all of them involve periodic autonomous precision landing of the aerial vehicle on the ground robot for recharging. Intelligent control systems like neural networks lend themselves naturally to precision landing applications since they offer immunity to system dynamics and adaptability to various environments. Our work describes an offline neural network backpropagation controller to provide visual servoing for the landing operation. The quadrotor control system is designed to perform precise landing on a marker platform within the specified time and distance constraints. The proposed method has been simulated and validated in a Gazebo and robot operating system simulation environment.

We report low frequency observations of Wolf-Rayet galaxies, NGC 4214 and NGC 4449 at 610, 325 and 150 MHz, using the Giant Meterwave Radio Telescope (GMRT). We detect diffuse extended emission from NGC 4214 at and NGC 4449. NGC 4449 is observed to be five times more radio luminous than NGC 4214, indicating vigorous star formation. We estimate synchrotron spectral index after separating the thermal free-free emission and obtain $\alpha_{nt}=-0.63\pm0.04$ (S$\propto\nu^{\alpha_{nt}}$) for NGC 4214 and $-0.49\pm0.02$ for NGC 4449. About $22\%$ of the total radio emission from NGC 4214 and $\sim 9\%$ from NGC 4449 at 610 MHz is thermal in origin. We also study the spectra of two compact star-forming regions in NGC 4214 from 325 MHz to 15 GHz and obtain $\alpha_{nt}=-0.32\pm0.02$ for NGC 4214-I and $\alpha_{nt}=-0.94\pm0.12$ for NGC 4214-II. The luminosities of these star-forming regions ($\sim 10^{19}\rm W~ Hz^{-1}$) appear to be similar to those in circumnuclear rings in normal disk galaxies observed with similar linear resolution. We detect the supernova remnant SNR J1228+441 in NGC 4449 and estimate the spectral index of the emission between 325 and 610 MHz to be $-1.8$ in the epoch 2008-2009. The galaxies follow the radio-FIR correlation slopes suggesting that star formation in Wolf - Rayet galaxies, which are low-metallicity systems, are similar to that of normal disk galaxies., Comment: 14 pages, 9 figures, 5 tables, Revised version submitted to MNRAS after incorporating the referee's comments

In this study, we propose a strategy to offset charge trapping and to enhance the confinement of excitons in the emissive layer of white electroluminescent copolymer using a luminogen with aggregation-induced emission enhancement (AIEE). The fluorenone-based luminogen, 2,7-bis(9H-fluoren-9-one-2yl)-9,9-dihexylfluorene (FF) that exhibited yellow emission with AIEE property is copolymerized with 9,9-dihexylfluorene in different compositions to tune the emission color. White-light emission is demonstrated in a copolymer FF-0.25, which contained 0.25% of FF in the polymer backbone. Interestingly, the copolymers exhibited enhanced emission upon aggregation in thin film, even in low FF composition. OLEDs fabricated from the copolymer FF-0.25 elicited a white electroluminescence with Commission Internationale de l'Eclairage (CIE) coordinates of 0.30, 0.31 with a power efficiency of 4.12 lm W−1. FF-0.25 showed very low charge trapping compared to other white emitting single polymer OLEDs reported to date. The reduced charge carrier trapping is attributed to the positioning of energy levels in the copolymer that resulted in almost equal electron- and hole-injection barriers. A theoretical investigation on the copolymers of FF revealed the presence of an ambipolar property and low exciton binding energy implicit of efficient formation and confinement of excitons within the emissive layer. The system represents the first ambipolar white electroluminescent polymer designed by using an AIEE luminogen.

The suitability of groundwater for irrigation uses was assessed in Alathur Block located in Perambalur District of the state of Tamil Nadu. Groundwater samples from ten villages were analyzed in two seasons for major cations, anions and other parameters such as electrical conductivity, total dissolved solids, Kelly’s ratio, sodium absorption ratio (SAR), magnesium ratio, % sodium, chloro-alkaline indices, residual sodium carbonate and permeability index to know the suitability of groundwater for irrigation purpose. Piper trilinear diagram interpretations were made to know the suitability of chemical type of the groundwater. It reveals that the subsurface water is alkaline (Na + K) than the alkaline earth (Ca + Mg) type. According to the SAR values plotted in the USSL Staff diagram, most of the groundwater samples belong to class high-salinity hazard and low-sodium hazard (C3−S1) and high-salinity hazard and medium-sodium hazard (C3−S2), which indicate that the groundwater of most stations require a special type of irrigation method.

Our study of solar high-latitude (≥45°) photospheric magnetic fields and interplanetary scintillation observations, at 327 MHz, of solar wind micro-turbulence levels showed a steady decline for the past 20 years. Also, the fact that cycle 24 has already past its peak, implies that high-latitude fields are likely to decline until ∼2020. Based on a correlation between the solar high-latitude fields and the heliospheric magnetic fields (HMF), we estimated the HMF strength in 2020 and the floor value of the HMF, which were found to be 3.9 (±0.6) nT and 3.2 (±0.4) nT, respectively. Using estimated value of the HMF in 2020, the peak sunspot number for solar Cycle 25 was estimated to be 62 (±12). These results and the fact that solar magnetic fields continues to decline at present raise the question of a very low sunspot activity in near-future or another grand minimum similar to the Maunder minimum. So what is the possible impact of such a likely grand minimum on terrestrial ionospheric current systems? Our study night time F-region maximum electron density (a measure of terrestrial ionospheric currents) reveals that the impending minimum is not likely to have any adverse impact rather the period post cycle 25 will be useful for undertaking systematic ground based low-frequency radio astronomy as the night time ionospheric cutoff-frequency could be well below 10 MHz.

The present study has been undertaken to investigate the physicochemical properties of soil samples of agricultural region collected from the Amaravathi river basin. The soil characterization was carried out for the parameters like pH, turbidity, total dissolved solids (TDS), total hardness (TH), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), bicarbonate \( ({{{\text{HCO}}_{3}}^{ - }} ) \), nitrate \( {{ ( {\text{NO}}_{3}}^{ - }} ) \), sulfate \( \left( {{{{\text{SO}}_{4}}^{2 - } }} \right) \), chloride (Cl−), fluoride (F−), phosphate \( \left( {{{{\text{PO}}_{4}}^{3 - } }} \right) \), iron (Fe), manganese (Mn), biochemical oxygen demand (BOD), and chemical oxygen demand (COD). A variety of values were observed in the different physicochemical parameters due to the soil quality in different sampling locations. Values of pH, chloride, fluoride, sulfate, BOD and COD concentration in the soil samples also showed wide variations. The groundwater samples of Amaravathi river were also analyzed for different water quality parameters. Comparing the analytical data with WHO and BIS standards, elevated concentration was observed in parameters like TDS, TH, Ca2+, Na+, Cl−, \( {{{\text{SO}}_{4}}^{2 - }} \), and COD which exemplify the degradation of water quality. Correlation analysis was carried out for soil samples and groundwater samples to investigate the relationship between the variables. Chlorinity and salinity index were performed for both soil and groundwater samples, and it was observed that most of the groundwater samples have medium to high chlorinity and salinity hazards. The microbiological characteristics of soil samples were carried out, and Bacillus and Pseudomonas species were the predominant bacteria genera isolated.

Aims: To calculate the power budget for electron acceleration and the efficiency of the plasma emission mechanism in a post-flare decimetric continuum source. Methods: We have imaged a high brightness temperature ($\sim 10^{9}$K) post-flare source at 1060 MHz with the Giant Metrewave Radio Telescope (GMRT). We use information from these images and the dynamic spectrum from the Hiraiso spectrograph together with the theoretical method described in Subramanian & Becker (2006) to calculate the power input to the electron acceleration process. The method assumes that the electrons are accelerated via a second-order Fermi acceleration mechanism. Results: We find that the power input to the nonthermal electrons is in the range $3\times 10^{25}$--$10^{26}$ erg/s. The efficiency of the overall plasma emission process starting from electron acceleration and culminating in the observed emission could range from $2.87\times 10^{-9}$ to $2.38 \times 10^{-8}$., Accepted for publication, Astronomy and Astrophysics

We discuss the results of two sessions of observations at the Low-Frequency VLBI Network (LFVN), carried out in 1999 (INTAS99.4) and 2000 (INTAS00.3) at a wavelength of 18 cm using the S2 recording system and processed using the correlator system in Pentictone, Canada. In different configurations of the experiments on studying the solar wind and active galactic nuclei, the antennas at the following sites were employed: Medvezhji Ozera (RT-64, Special Engineering Bureau of Moscow Power Engineering Institute, Russia), Pushchino (RT-22, Pushchino Radio Astronomy Observatory, Russia), Hartebeesthoek (RT-25, South Africa), Noto (RT-32, Italy), Shanghai (RT-25, China), Pune (RT-45, India), Svetloe (RT-32, Institute of Applied Astronomy RAS, Russia). The work resulted in successful testing of the method of radio probing of the solar-wind plasma by radiation of extragalactic sources, supplemented with the method of radio interferometric reception. Spectral analysis of the obtained data allowed us to estimate the index of spatial spectrum of the electron number density.uctuations and the transfer velocity of the solar-wind inhomogeneities on the sounding path. We present and discuss the retrieved images of STA-102 quasar and the BL Lacertae object 1418+546 with millisecond angular resolution and demonstrate the results of modeling the structure of these sources.