Genetic variability of the bollworm, Helicoverpa armigera, occurring on different host plants

The bollworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) is a polyphagous pest of worldwide occurrence inflicting annual crop damage in India worth US$ 1billion. In India this insect occurs as a major pest in many economically important crops, including cotton, pigeonpea, chickpea, tomato, okra, and blackgram. Understanding the genetic variation among the H. armigera populations occurring on host plants has become essential to understand the variation in their susceptibility to different insecticides, including Bacillus thuringiensis. This preliminary study uses 10 microsatellite simple sequence repeat (SSR) markers, to provide insight into the genetic variability of H. armigera populations from six different host plants. Nine of the SSR primers indicated high variability across the different host associated populations with polymorphism ranging from 75 to 100 per cent. Using the un-weighted pair-group method analysis, H. armigera collected and reared from cotton stood out as unique in one cluster while the insects collected and reared on all other hosts grouped separately

POWER QUALITY IMPROVEMENT USING 5-LEVEL FLYING CAPACITOR MULTILEVEL CONVERTER BASED DYNAMIC VOLTAGE RESTORER FOR VARIOUS FAULTS

This paper present the use of five level flying capacitor multilevel converters based dynamic voltage restorer (DVR) on power distribution system to decrease the power-quality disturbances in distribution system, such as voltage imbalances, harmonic voltages, and voltage sags. This DVR based five multilevel topology is suitable for medium-voltage applications and operated by the control scheme based on the so called repetitive control. The organization of this paper has been divided into three parts; the first one eliminates the modulation high-frequency harmonics using filter increase the transient response

Leveraging supercapacitors to mitigate limitations and enhance the performance of battery energy storage systems: A simulation and experimental validation

Abstract The importance of supercapacitors has grown significantly in recent times due to several key features. These include their superior power density, faster charging and discharging capabilities, eco-friendly nature, and extended lifespans. Battery Energy Storage Systems (BESS), on the other hand, have become a well-established and essential technology in the field of energy storage. However, BESS still faces challenges such as lower power density, limited cycle stability, and potential chemical hazards. Additionally, batteries perform poorly during transient events (sudden changes in power) due to their larger time constants, which can also shorten their lifespan. By strategically combining supercapacitors with BESS, their combined strengths can optimize battery performance. This study explores the role of supercapacitors in enhancing battery performance through both simulation and experimentation. The results obtained experimentally matched with simulated results

Determination of Damping Coefficient of a Bump Foil Squeeze Film Damper

The present investigation is aiming to get better squeeze film dampers which are normally used in high speed jet engines to minimize small amplitude large force vibrations. The investigation was started with squeeze film dampers employing conventional lubricating oils. Magneto rheological fluids are then used to enhance the viscosity characteristics of the fluid under the influence of magnetic fields in order to improve the damper performances. It is observed that the dynamic characteristics of the damper with magneto rheological fluids are enhanced. Further to improve the damper performance, few modifications in the damper assembly are carried out in this research work. A good amount of reduction in the amplitude of vibrations is observed in these modified squeeze film dampers coupled with magneto rheological fluids. This research work discusses dual and triple clearance squeeze film dampers and bump foil squeeze film damper, also subjected to variation in temperature. Dynamic characteristics are found to be decreasing as the viscosity of the fluid decreases with rise in temperature of the fluid.</jats:p