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The study aimed to compute the effective dose (E) and size‑specific dose estimate (SSDE) of routine adult patients undergoing thorax and abdominal computed tomography (CT) imaging and to present their multivariate analysis. All adult thorax and abdominal CT examinations conducted from March 2022 to June 2022 were prospectively included in this study. The Water Equivalent Diameter (Dw) and SSDE of all the examinations were computed from CT dose index volume (CTDIvol) and Dose length product (DLP) displayed on the dose report in the CT console. The multivariate statistical analysis was performed to investigate the correlation of SSDE and E on CTDIvol, Dw area of the region of interest (ROI) (AreaROI), body mass index (BMI), conversion factor (f size) and hounsfield (HUmean) number in the ROI at 95% level of significance (P < 0.05). The linear regression analysis was performed to investigate the dependence of SSDE and E on other parameters for both abdominal and thorax patients. A total number of 135 (Abdomen = 61 and Thorax = 74) measurements were performed. The mean value of effective dose for abdomen and thorax patients was found to be 7.17 ± 3.94 and 4.89 ± 2.16 mSv, respectively. The SSDE was observed to be 13.24 ± 3.61 and 13.04 ± 3.61 mGy for thorax and abdomen respectively. The multivariate analysis suggests that SSDE for abdominal CT is found significantly dependent on CTDIvol, Dw and fsize with P < 0.05 and E is found to be significantly dependent on DLP, AreaROI, Dw and fsize at 95% level of confidence for abdominal CT imaging. SSDE for thorax CT was found significantly dependent on BMI, CTDIvol, HUmean, Dw and fsize at 95% level of confidence. Furthermore, E was observed dependent on DLP at P < 0.05. The linear regression analysis also shows that E is strongly correlated with DLP (r = 1.0) for both thorax and abdominal CT, further the SSDE was observed strongly correlated with CTDIvol with r = 0.79 and r = 0.86 for abdomen and thorax CT respectively. A strong correlation was observed between BMI and for Dw abdominal CT imaging (r = 0.68). The mean value of SSDE for thorax is slightly greater than abdomen. The average value of effective dose for abdomen and thorax measurements was found to be 7.17 ± 3.94 and 4.89 ± 2.16 mSv and, correspondingly. SSDE for both abdomen and thorax CT is significantly dependent on CTDIvol, Dw and fsize at 95% level of confidence. The strong correlation was also observed E on DLP and SSDE on CTDIvol for both Abdomen and Thorax CT. The strong dependence of Dw on BMI (r = 0.68) is due to the excessive fat concentration around the stomach and abdomen. [ABSTRACT FROM AUTHOR]

Hematite (α-Fe2O3) nanoparticles were synthesized by modified solution combustion method using a mixture of hexamethylenetetramine (HMTA) and glycine fuels at fuel to oxidant molar ratio (ϕ = 1) and fuel (HMTA) to fuel (glycine) weight ratio (1:3). DC-conductivity and dielectric studies of (α-Fe2O3) nanostructures were reported as a function of temperature. Above room temperature (RT), the conductivity showed an increasing trend with temperature which confirmed the semiconducting behaviour of the material. The conductivity behaviour followed Motts law which confirmed the three dimensional variable range hopping (3D VRH) mechanism in the synthesized system. Dielectric studies were carried out at room temperature with frequency range (1000 Hz to 1.5 MHz) as well as varying temperature (100 °C to 400 °C) at different frequencies (0.1 MHz, 0.3 MHz, 1 MHz, 1.3 MHz, and 1.5 MHz).The dielectric permittivity (є')and tangent loss (tan δ) was found to increase with increase in temperature. In this synthesised material low value of dielectric loss was observed which depicted these materials as potential candidates for microwave applications. More than that studied material was characterised by Raman spectroscopy which revealed that seven active Raman modes were present with different intensities, namely two "A1g" modes (225 and 498 cm−1) and five "Eg" modes (247, 293, 299, 412 and 613 cm−1). The most representative band present in the synthesised iron oxide nanoparticles was found at 225 cm−1. [ABSTRACT FROM AUTHOR]

For shielding voltage sensitive loads from diverse power quality problems (Voltage harmonic distortion and voltage sag/swell) a wide variety of custom power devices are used. Dynamic voltage restorer (DVR) is one of the important custom power device presently used for mitigation of above mentioned power quality problems. In this paper, reduced-rule fuzzy logic controller based on synchronous reference frame theory for controlling of self-supported dynamic voltage restorer (DVR) is proposed. As a result of the proposed controller, the mathematical model of plant is not at all needed and the control signals required by the DVR are thoroughly provided during various types of power quality problems at the source side. The performance of this technique is better than the other existing techniques and it is very simple to implement, less complex, very flexible and robust in nature. For the same system parameters, the fuzzy logic based controller uses the less amount of reactive power to mitigate the various disturbances at source side compared to PI based controller, which results into reduced rating of IGBTs and consequently leading to lowering of the overall cost. DVR is simulated for mitigation of various power quality problems (voltage harmonic distortion, balanced voltage sag/swell, unbalanced voltage sag/swell, balanced voltage sag/swell with harmonic distortion and unbalanced voltage sag/swell with harmonic distortion) and the simulation results verified by experimental results are presented displaying the workability of proposed controller. [ABSTRACT FROM AUTHOR]

LaFe1-xMnxO3 (x ≤ 0.5) polycrystals have been prepared using solid-state reaction technique and characterized by X-ray diffraction and electrical transport. XRD data suggest orthorhombic structure for both pure and Mn-doped compositions with space group Pbnma. However, unit cell dimensions are found to decrease with increase in Mn concentration. Resistivity data have been fitted with variable range hopping (VRH) model, from which different parameters like density of state at Fermi level N(Ef), hopping energy (Eh), and hopping distance (Rh) were estimated. It was observed that substitution of Mn in the series leads to the increase in conductivity of the samples with conduction being controlled by the disorder-induced localization of charge carriers. [ABSTRACT FROM PUBLISHER]