Origin of Ferroelectricity in Orthorhombic LuFeO3_3

We demonstrate that small but finite ferroelectric polarization ($\sim$0.01 $\mu$C/cm$^2$) emerges in orthorhombic LuFeO$_3$ ($Pnma$) at $T_N$ ($\sim$600 K) because of commensurate (k = 0) and collinear magnetic structure. The synchrotron x-ray and neutron diffraction data suggest that the polarization could originate from enhanced bond covalency together with subtle contribution from lattice. The theoretical calculations indicate enhancement of bond covalency as well as the possibility of structural transition to the polar $Pna2_1$ phase below $T_N$. The $Pna2_1$ phase, in fact, is found to be energetically favorable below $T_N$ in orthorhombic LuFeO$_3$ ($albeit$ with very small energy difference) than in isostructural and nonferroelectric LaFeO$_3$ or NdFeO$_3$. Application of electric field induces finite piezostriction in LuFeO$_3$ via electrostriction resulting in clear domain contrast images in piezoresponse force microscopy.Comment: 12 pages, 8 figure

Modeling and Simulation of a Single Phase Matrix Converter with Reduce Switch Count as a Buck/Boost Rectifier with Close Loop Control

This Paper focused on Buck/Boost Rectification by Single Phase Matrix Converter with fewer numbers of switches. The conventional matrix converter consists of 4 bidirectional switches, i.e. 8 set of IGBT/MOSFET with anti parallel diodes. In this proposed matrix converter, only six switches are used. The switch commutation arrangements are also carried out in this work. The gate pulses to the switches are provided by the PWM techniques. Step up or step down DC outputs can be obtained by using suitable switching algorithm. The PSIM simulation results are provided to validate the feasibility of this proposed method

Interline Unified Power Quality Conditioner for Enhancing Power Quality using FOFPID-based Interleaved CUK Converter

Electrical distribution systems face increased non-linear loads due to using power electronics for the converters. Due to these non-linear loads, the system exhibits PQ problems in the distributed feeders. To enhance PQ problems in the dual feeder, fractional order fuzzy proportional integral derivative controller (FOFPID) is introduced with interline unified power quality (IUPQC) conditioner. IUPQC conditioner includes a distribution static compensator (DSTATCOM), dynamic voltage restorer (DVR) and interleaved cuk converter (ICC). DSTATCOM and DVR are used for compensating the voltages and current in the dual feeders (feeder-1 and feeder-2). Also, ICC monitors the switching between the DSTATCOM and DVR compensators by providing proper power flow. Moreover, the FOFPID controller regulates an input supply from both feeders. The simulation is performed through MATLAB/Simulink platform, demonstrating the robustness of a proposed FOFPID with an IUPQC controller. The performance of a proposed controller is analyzed through two cases for both feeders. Furthermore, the total harmonic distortions (THD) are calculated for the feeder parameters. The proposed FOFPID with IUPQC controller also maintains stability in a dual feeder. Therefore, the entire response shows the functionality and feasibility of a proposed controller

Vibration Control Of Steel Frames Using Magnetorheological Dampers: A New Control Algorithm.

Control technologies application to steel structure is mainly anticipated to enhance the structural performance against natural hazards. In particular smart base isolation system connected with semi-active isolator at the base with controllable semi devices gaining impulse for its efficiency and economic reasons. Generally the development of control design strategies through system dynamics concept had not been considered entirely for structural applications. Structural characteristics which help to divulge structural properties, hitherto flout by civil engineering circle are assimilated with control techniques to construct indices in modal and nodal coordinates for the endurance of the control action to utilize their fullest capabilities. In this study, an isolated 3D steel frame model is developed.  Magneto-Rheological dampers are fixed with 3D steel frame model which act as a smart control device. Besides, Force transducers and Piezoresistive Actuator in tandem with Deltatron conditioning amplifier are also used. Presently many techniques are employed for the optimum placement of actuators and sensors in vibration control systems. The concept of controllability-observability is used in these methods. The specific relationship between the vibration modes and controllability-observability simplifies this approach. This study envisaged the compatibility of force transducers along with triaxial and uniaxial accelerometers fixed at various trial spots on the model structure to quantify the damping force and absolute accelerations of the structure and the dampers individually, positioned in the system, against the excitation of the structure

In vitro micropropagation of Musa sapientum L. (Cavendish Dwarf)

A complete protocol for micropropagation of Musa sapientum using shoot meristems was developed. Multiple shoots were induced in vitro from shoot meristems. Murashige and Skoog’s medium supplemented with BAP and NAA (3.0 + 0.2 mg/l, respectively) was found to be most suitablecombination. Further multiplication of shoots required habituation of cultures up to 3 passages of 21 days each on the same medium after establishment of culture and initiation of shoot buds. Thereafter 3-fold multiplication rate was achieved during every subculture. For rooting the shoots were excised and transferred to same medium. Rooted plantlets were then transferred to primary and secondary hardening and grown in the green house. These hardened plants have been successfully established insoil

Pesticide Consumption Trends in India

Aims: The main aim of this study is to examine the growth rate of consumption of pesticides in India and Tamil Nadu. Place and Duration of Study: The study was carried out using the time series data on pesticide consumption collected from secondary sources from 1990 to 2020 for India and for Tamil Nadu, the data were collected from 2011 to 2021. Methodology: The compound annual growth rate is used to calculate the growth rate of consumption of pesticides. The data is segmented for every 10 years and decadal growth rate was also examined. Results: The overall compound annual growth rate of pesticide consumption is negative(-0.44 per cent) and the decadal average was found to be -5.27%, -0.73% and 1.81% for the decades 1990-2000, 2001-2010 and 2011-2020 respectively for India. The growth rate for different types of pesticides was found to be declining (-2.26 per cent) for insecticides, however it is increasing for fungicides (2.65 per cent) and herbicides (0.99 per cent). CAGR indicates that there is no change in growth of pesticide consumption in Tamil Nadu. Conclusion: The trend in the pesticide use has been decreasing over the period and it shows that the total quantity of pesticides used in the country has been continuously decreasing which is a healthy sign for the environment. It may due to increase in the area of organic farming, practices like IPM  and increase in the use of biopesticides

A Smart Remote Monitoring System for Prenatal Care in Rural Areas

The complications in maternity especially the women lives in rural sector can be reduced through regular monitoring of their vitals like blood pressure, SpO2 and fetal growth. The internet of things (IoT) is the modern technology bridges the gap between the traditional clinical setting with its consumers as well promotes the telemedicine industry into great levels of accessing proactive healthcare facilities. The predominant aim of this work is to bring a remote monitoring device which assesses the significant health indicators of the pregnant women and their fetus status cost effectively. In order to build such kit, the biosensors like heart rate, SpO2, pressure, temperature and load cell which gives the weight of the fetus are integrated into Arudino board. The sensor readings are processed through ThingSpeak. The timely medical attention is proposed upon observing abnormal physiological vitals of the women which is implemented through a buzzer system in this device. Like such devices in realism help to predict the pregnancy risk and decrease the mortality rate

Influence of milled glass fiber fillers on mode I & mode II interlaminar fracture toughness of epoxy resin for fabrication of glass/epoxy composites

The present work is focused on improving mode I and mode II delamination resistance of glass/epoxy composite laminates (50 wt. % of glass fibers) with milled glass fibers, added in various amounts (2.5, 5, 7.5 and 10% of the epoxy weight). Including fillers in the interlayer enhances the delamination resistance by providing a bridging effect, therefore demanding additional energy to initiate the crack in the interlaminar domain, which results in turn in enhanced fracture toughness. The maximal increase of mode I and mode II fracture toughness and of flexural strength was obtained by the addition of 5% milled glass fiber. The mechanism observed suggests that crack propagation is stabilized even leading to its arrest/deflection, as a considerable amount of milled glass fiber filler was oriented transverse to the crack path. In contrast, at higher filler loading, tendency towards stress concentration grows due to local agglomeration and improper dispersion of excess fillers in inter/intralaminar resin channel, causing poor adhesion to the matrix, which leads to reduction in fracture toughness, strength and strain to failure. Fractured surfaces analyzed using scanning electron microscopy (SEM) revealed a number of mechanisms, such as crack deflection, individual debonding and filler/matrix interlocking, all contributing in various ways to improve fracture toughness