Digital modelling for performance prediction of hysteresis motors

The performance prediction of the hysteresis motor depends largely on the success of optimized representation of the actual B-H loop of its rotor hysteresis material. Digital simulation of the typical hysteresis materials like 175 cobalt steel, 36% cobalt steel and Oerstit-70 alloys having coercivity lying between 4 and 20 kA/m and remanent flux density lying between 0.8 and 1.3 T are carried out. The simulation is based on the modified Frölich’s approach. Reasonably close agreement is found between the simulated and those supplied by the power magnet manufacturing company. -- On the basis of parallelogram approximations analytical models of the circumferential-flux hysteresis motor have been given. The motor field equations are then solved, to predict the terminal quantities, using the digital B-H loop modelling. The air-gap power of the hysteresis motor is studied as a function of coercive force, remanent flux density, saturated relative permeability and unsaturated relative permeability of the hysteresis material. A series of tests were carried out using 17% cobalt steel hysteresis rotor. The reasonably close agreement between the terminal quantities predicted form the digital simulation and those measured experimentally validates the usefulness of digital simulation of the hysteresis motor

Susceptibility of Different Populations of Nilaparvata lugens from Major Rice Growing Areas of Karnataka, India to Different Groups of Insecticides

Abstract: Susceptibility to insecticides was investigated by collecting field populations of brown planthopper from different locations of southern Karnataka, India (Gangavati, Kathalagere, Kollegala, Soraba and Mandya). All the field populations differed in their susceptibility to insecticides. In general, Soraba and Mandya populations were more susceptible to insecticides compared to Gangavati and Kathalagere populations. The resistance ratios varied greatly among the populations viz., chlorpyriphos (1.13 to 16.82), imidacloprid (0.53 to 13.50), acephate (1.34 to 5.32), fipronil (1.13 to 4.06), thiamethoxam (1.01 to 2.19), clothianidin (1.92 to 4.86), dinotefuran (0.82 to 2.22), buprofezin (1.06 to 5.43) and carbofuran (0.41 to 2.17). The populations from Gangavati, Kathalagere and Kollegala exihibited higher resistance to some of the older insecticides and low resistance to newer molecules

Identification of usable maintainers and restorers for new CMS lines of rice (O. sativa L.)

The success of hybrid rice technology depends on the extent of heterosis realized and the grain quality of rice. Seven new CMSlines developed at Zonal Agricultural Research Station, Mandya through backcross breeding were evaluated along with twochecks CRMS31A and CRMS 32A for their morphological and floral traits besides aroma during kharif 2008. All the CMSlines evaluated exhibited complete pollen sterility and spikelet sterility. KCMS 29A recorded the higher stigma exsertion(30.31%) and natural outcrossing (19.76%). KCMS 31A had the longest style (1.26 mm) and stigma (1.20 mm) while the anglebetween stigma lobes was wider ( 65.48 (φ)) in KCMS 37A which also had the best panicle exsertion (79.28%). All the nineCMS lines had no aroma. Based on morphological and floral traits CMS lines KCMS 29A, KCMS 31A and KCMS 37A werebetter compared to the checks CRMS 31A and CRMS 32A. To identify usable maintainers and restorers for these CMS lineseleven testers were crossed with all the nine CMS lines in a line x tester fashion. Based on the percent spikelet fertility inhybrids, 60 showed restorer reaction and eight had maintainer reaction while the rest 31 showed partial maintainer / restorerreaction. Among the testers MSN-20-13, MSN-62, MSN-63, MSN-64 and MSN 68 were identified as good maintainers whileKMR-3, KMR-4, MSN-67 and MSN-69 as good restorers

SEASONAL INCIDENCE OF COCONUT MOTH, BATRACHEDRA ARENOSELLA WALKER (LEPIDOPTERA : BATRACHEDRIDAE)

Coconut moth, Batrachedra arenosella Walker (Lepidoptera : Batrachedridae) infestation was proved to be one of the major factors responsible for immature nut fall in coconut ecosystem in South India. The larvae feed on the mesocarp of immature nuts under the perianth forming a silken web with excretory pellets. Its infestation predisposes the nuts to secondary infection by other pests and micro organisms. Feeding by B. arenosella larvae near the stalk of the nut leads to premature nut fall. Therefore investigations on the seasonal incidence of were undertaken at V.C. Farm, Mandya during 2011-12. Its incidence was more abundant on coconut during August. Adults were active throughout the year as evidenced by moth catches in all the months. The trap catches of B. arenosella exhibited a negative association with weather parameters viz., maximum temperature, sunshine hours, rainfall and positive relation with minimum temperature, morning relative humidity and afternoon relative humidity. The trap catches were found to be significantly positively correlated with wind speed. Nut damage by the larvae exhibited a negative association with maximum temperature, sunshine hours and rainfall. The incidence of the larvae was observed in the intact nuts throughout the year. An average of 11.82% incidence was observed on intact nuts which accounts for 22.39% of fallen nuts. A positive association was observed between adult trap catches and field incidence of B. arenosella on the immature nuts

Acylation of Grignard reagents mediated by N-methylpyrrolidone: A remarkable selectivity for the synthesis of ketones

An efficient user-friendly method of acylation of Grignard reagents to selectively synthesize ketones is presented, which is assisted by simple amides such as NMP, or DMF. The present chemoselective method tolerates a variety of functional groups such as ketone, ester, nitrile and other functional groups

Gender identity in urban poor mobilizations: evidence from Bengaluru

This paper draws on field research conducted among a group of resettled slum(1) dwellers in the west of Bengaluru, and analyzes women's collective engagement to improve the provision of urban services in low-income neighbourhoods. The paper argues the need to deepen the focus on urban poor mobilizations below the level of the urban poor as a group - to look at the various groups, and the differences, divergences and contradictions within. Using gender as a differential, the paper focuses on women who dominate local neighbourhood level initiatives within low-income settlements, and analyzes their specific opportunities and constraints as actors within the larger domain of urban poor mobilizations. It proposes that these seemingly insignificant day-to-day negotiations diverge from more individual forms of "leadership", creating a political space at the lowest level of the neighbourhood where the projects of material improvement and emancipation take place simultaneously

A Test of the Perseverative Cognition Hypothesis Using Hair Cortisol in a Sample of Dementia Caregivers and Non-Caregiver Controls

Rice molecular linkage map obtained from 107 SSR and STS markers of 151 F2:3 mapping population of the cross combination Jaya × CR2711–76. Chromosome numbers are presented on the top of each linkage group, marker names are presented on the right side of each linkage group, and their intervals in cM are presented on the left side of the linkage group. This linkage group was generated by QTL IciMapping software considering the marker position and order retrieved from MAPMAKER ver. 2.0. (PPTX 160 kb

Additional file 4: Figure S4. of Identification and fine mapping of a new gene, BPH31 conferring resistance to brown planthopper biotype 4 of India to improve rice, Oryza sativa L

The schematic diagram of primary mapped BPH resistance locus BPH31 on chromosome 3 flanked by RM251 and RM2334 with 48.40 LOD and 80.71% phenotypic variance explained derived from 151 F2:3 mapping population in the whole-genome view. This result was retrieved from the linkage analysis of (a) QTL IciMapping ver. 4.0 (Meng et al. 2015) and (b) WinQTL cartographer ver. 2.5 (Wang 2012) software package. (PPTX 658 kb