-Partial discharge (PD) measurements have emerged as a dominant investigative tool for condition monitoring of insulation in high voltage equipment. But the major problem behind them the PD signal is severely polluted by several noises like White noise, Random noise, Discrete Spectral Interferences (DSI) and the challenge lies with removing these noise from the onsite PD data effectively which leads to preserving the signal for feature extraction. Accordingly the paper is mainly classified into two parts. In first part the PD signal is artificially simulated and mixed with white noise. In second part the PD is measured then it is subjected to the proposed denoising techniques namely Translation Invariant Wavelet Transform (TIWT). The proposed TIWT method remains the edge of the original signal efficiently. Additionally TIWT based denoising is used to suppress Pseudo Gibbs phenomenon. In this paper an attempt has been made to review the methodology of denoising the PD signals and shows that the proposed denoising method results are better when compared to other wavelet-based approaches like Fast Fourier Transform (FFT), Discrete Wavelet Transform (DWT), by evaluating five different parameters like, Signal to noise ratio, Cross-correlation coefficient, Pulse amplitude distortion, Mean square error, Reduction in noise level.

This work reports the coprecipitation synthesis and characterization of single-phase Sm3+/Sr2+/Ca2+ codoped with Gd3+ in cerium oxide formulated as Ce0.8M0.1Gd0.1O2−δ (CMGO; M = Sm3+, Sr2+, Ca2) nanopowder and their nanocomposites with sodium carbonate formulated as Ce0.8M0.1Gd0.1O2−δ–Na2CO3 (CMGO-NC). The structural properties of both the CMGO and CMGO-NC compositions were investigated by X-ray diffraction (XRD), Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM) techniques. The XRD results revealed that the crystallite sizes of the codoped ceria–sodium carbonate nanocomposite (CMGO-NC) were lower (∼8–15 nm) than their corresponding single-phase codoped ceria compositions. CMGO-NC has shown improved electrical conductivity in the intermediate temperature range (673–973 K), as measured by alternating-current impedance spectroscopy. The highest total electrical conductivity was found to be σ973 K = 2.3 mS·cm–1 with significantly reduced activation energy (E a = 0.63 eV) for Ca–Gd-codoped ceria–sodium carbonate Ce0.8Ca0.1Gd0.1O1.85–Na2CO3 (CaG-NC). The morphologies of both the single-phase CaG and corresponding CaG-NC nanocomposite were investigated by field-emission scanning electron microscopy (FESEM) and HRTEM techniques in order to determine the size and shape effect by the sodium carbonate addition to the codoped ceria nanopowders. The FESEM images of the CaG-NC nanomposite showed significantly reduced particle size. The HRTEM images revealed that the secondary Na2CO3 phase was found to be an amorphous layer that has covered codoped ceria (Ce0.8Ca0.1Gd0.1O1.85) particles as a core–shell structure. The X-ray photoelectron microscopy studies support the CaG-NC composition and surface interaction between the carbonate and crystalline CaG phases. Enhancement in the net electrical conductivity of nanocomposites could be due to the reduced particle size and the core–shell morphology, which enables the superionic interfacial conduction in the composite. The CaG-NC core–shell nanocomposite is proposed to be a cost-effective variant of the solid electrolyte with improved electrical properties for operating solid oxide fuel cells at low/intermediate temperature (673–973 K).

Horseshoe kidney (HSK) is a rare congenital malformation of the kidneys and is commonly associated with other anomalies of the renovascular and ureteropelvic systems. These anomalies present a surgical challenge, especially for surgeries involving the retroperitoneum. We present the case of a 56-year-old male patient with biopsy-proven rectal cancer who had completed neoadjuvant chemoradiation and was planned for curative resection. Contrast-enhanced computed tomography (CECT) of the abdomen and pelvis revealed the presence of an HSK. Reconstructed three-dimensional (3D) images of the renal vasculature revealed the presence of an accessory renal artery originating directly from the aorta and supplying the isthmus of the HSK without any other venous or ureteral anomalies. Laparoscopic abdominoperineal resection with total mesorectal excision was done without any untoward complications. The presence of HSK per se is not a contraindication for laparoscopic operations involving the retroperitoneum. Pre-operative 3D CECT helps to identify the presence of anatomical variations and guides surgical resection.

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