Turn-to-turn fault diagnosis of an Induction motor by the analysis of Transient and Steady state Stator current

This work proposes an online diagnosis of turn-to-turn stator winding fault of an induction motor through the combine use of Wavelet Transform (WT) and Fast Fourier Transform (FFT). Both steady state and non-stationary transient part of motor stator currents are assessed for detection of this inter turn short circuit fault. First non-stationary part is assessed by formation of contour of the coefficients of Continuous Wavelet Transform (CWT) of stator current – result shows significant change of amplitude at certain frequencies. Secondly, the supply frequency is filtered off from the steady part of motor current. Then on this filtered signal (i) Fast Fourier Transform (FFT) is performed where from spectrums are observed at different percentage of inter turn short condition and (ii) performing Discrete Wavelet Transform (DWT) detailed wave energy has been calculated using Parseval’s theorem. Work has been performed both under load and no-load condition of the motor. The proposed method has been validated in a laboratory prototype. Results indicate that the proposed technique is suitable for real-time application Keywords: CWT, DWT, FFT, fault diagnosis, induction motor, inter-turn short, wave energ

Novel processing method for improved antioxidant and nutritional value of elephant foot yam (Amorphophallus paeoniifolius Dennst-Nicolson)

206-211Amorphophallus paeoniifolius Dennst-Nicolson, commonly known as the Elephant foot yam, is a highly potential edible aroid of Araceae family. Fresh yams are difficult to store due to their perishable nature and deteriorate in quality during storage. Therefore, making processed products viz., dry and fry cubes will be an alternative value added product with nutritional value. In this experiment, elephant foot yam corm cubes were stored to analyze the nutritional and antioxidant values at monthly intervals. The cv., BCA-1 dry cubes (soaking in 2% salt followed by blanching) had the highest ascorbic acid and total phenol throughout the storage period. Highest β-carotene was observed in cv., IGAM-1 dry cubes (2% alum) and fry cubes (2% alum) at 0 and 13 months after storage, respectively. The cv., BCA-1 had the highest starch in dry cubes (1.5% alum) and fry cubes (2% salt) at 0 and 13 months after storage, respectively. The protein and organoleptic values were the highest throughout the storage in cv., BCA-1, both dry and fry cubes, were from soaking in 1.5% alum and blanching

W(0,b)W(0,b) algebra and the dual theory of 3D asymptotically flat higher spin gravity

BMS algebra in three spacetime dimensions can be deformed into a two parameter family of algebra known as $W(a,b)$ algebra. For $a=0$, we show that other than $W(0,-1)$, no other $W(0,b)$ algebra admits a non-degenerate bilinear and thus one can not have a Chern-Simons gauge theory formulation with them. However, they may appear in a three-dimensional gravity description, where we also need to have a spin 2 generator, that comes from the $(a=0,b=-1)$ sector. In the present work, we have demonstrated that the asymptotic symmetry algebra of a spin 3 gravity theory on flat spacetime has both the $W(0,-1)$ and $W(0,-2)$ algebras as subalgebras. We have also constructed a dual boundary field theory for this higher spin gravity theory by using the Chern-Simons/Wess-Zumino-Witten correspondence.Comment: 27+5 pages; 3 appendice

Phase coexistence and resistance relaxation kinetics in NdNiO3 films below the metal-insulator transition temperature

Coexistence of electronically distinct phases below metal-insulator (MI) transition temperature (T-MI) in correlated oxides undergoing temperature-driven MI transition has been observed in a number of systems. One of the consequences of the coexisting phases is that the metastable high-temperature metallic phase transforms into the stable insulating phase with a finite relaxation time as the temperature is lowered below T-MI. We report an extensive investigation of the phase transformation (referred to as relaxation) using resistivity as a tool where the ramp-dependent hysteresis and isothermal annealing-induced resistance relaxation were studied in films of NdNiO3 grown on three different crystalline substrates (LaAlO3, SrTiO3, and BaTiO3/SrTiO3) down to 10 K, well below the metal-insulator transition temperature. The resistance relaxation experiments were complemented with Raman spectroscopy and high-resolution x-ray diffraction done down to 5 K and reciprocal space mapping (RSM). Isothermal annealing experiment done to temperatures 0 at this temperature. The resistance relaxation data were linked to x-ray diffraction and Raman spectroscopy data done to temperatures well below T-MI, in order to have a structural basis for the coexisting phases and their likely participation in the relaxation process. The experiments (both hysteresis and isothermal annealing) were analyzed by Monte Carlo simulation based on a minimal set of parameters, namely, a temperature T* and an energy scale of transformation E*, which themselves had a temperature dependence. The parameters used in the simulation and other experimentally observed quantities like the width and height of hysteresis were found to be correlated with certain structural parameters, in particular, the residual in-plane strain and the crystallite grain size that determine the size range in these films

Fertilizer best management practices by SSNM and customized fertilizers for elephant foot yam (Amorphophallus paeoniifolius) cultivation in India

Elephant foot yam [Amorphophallus paeoniifolius (Dennst.) Nicolson] is an important tuber crop grown in many parts of India for its starchy corm and the average yield of this crop is far below the potential productivity of 100 tonnes/ha. One of the reasons attributed to the lower yield is the imbalanced application of essential plant nutrients. Site specific nutrient management (SSNM) is the application of plant nutrients based on the soil and crop need, yield target and developed with the aid of models such as QUEFTS. This paper gives the result of four year study conducted to calibrate and validate the QUEFTS model for elephant foot yam cultivation and the development of SSNM zonation maps and secondary and micronutrient fortified customised fertilizers for the crop in major growing environments of India. Data collected from different field experiments conducted in major elephant foot yam-production regions of India during 1968 to 2011 were used to calibrate the model. The derived parameters of minimum and maximum accumulation of N (130 and 460), P (900 and 2100) and K (100 and 170) are proposed as standard borderline values in the QUEFTS model for elephant foot yam. A linear increase in corm yield was suggested by the model with N, P and K uptakes of 3.97, 0.71, and 7.05 kg N, P and K/1 000 kg corm. The average NPK ratio in total plant dry matter was 5.56:1:9.88. Based on these results, the model was calibrated using historical data as well as by conducting field experiments. It can be observed that fertilizer best management practices by SSNM resulted in an average actual corm yield of 33.45 tonnes/ha, whereas, the model predicted a yield of 35 tonnes/ha. The results of the study showed good agreement between predicted and measured corm yields during the four years, which indicated that the calibrated model can be used to improve NPK fertilizer recommendations for elephant foot yam in India. Based on the results and using soil fertility maps and agro ecological unit maps, SSNM zonation maps and secondary and micronutrient fortified customised fertilizers were developed for major elephant foot yam growing environments of India