Stir casting studies on aluminium (Al8011) and zirconia (ZrO2) metal matrix composites

This study investigates the properties of Aluminium (Al8011) and Zirconia (ZrO2) metal matrix composites (MMCs) fabricated through stir casting, which is a common technique used to produce MMCs. Al8011 was used as the matrix material whilst ZrO2, a ceramic material, was used as the reinforcement. The composites were developed with varying weight percentages of ZrO2 (4, 8 and 12 wt%) and were analysed using tensile, wear and hardness, scanning electron microscopy (SEM) and hardness testing. The findings show that as the percentage of ZrO2 increased in the composites, the density and hardness significantly increased. SEM results revealed that the distribution of ZrO2 was homogenous throughout the matrix, indicating the method of stirring was effective in improving particle dispersion. Overall, the study concluded that MMCs with high percentage of ZrO2 has the potential to enhance mechanical and physical properties whilst maintaining insignificant level of porosity. However, future research is needed to address the impurities identified in this study

Auditory Temporal Resolution in Normal-Hearing Preschool Children Revealed by Word Recognition in Continuous and Interrupted Noise

The purpose of this study was to examine temporal resolution in normal-hearing preschool children. Word recognition was evaluated in quiet and in spectrally identical continuous and interrupted noise at signal-to-noise ratios (S/Ns) of 10, 0, and −10dB−10dB−10dB. Sixteen children 4to5years4to5years4to5yearsof age and eight adults participated. Performance decreased with decreasing S/N. At poorer S/Ns, participants demonstrated superior performance or a release from masking in the interrupted noise. Adults performed better than children, yet the release from masking was equivalent. Collectively these findings are consistent with the notion that preschool children suffer from poorer processing efficiency rather than temporal resolution per se

Detection of glaucoma from fundus image using pre-trained Densenet201 model

33-39In recent years, the performance of deep learning algorithms for image recognition has improved tremendously. The inherent ability of a convolutional neural network has made the task of classifying glaucoma and normal fundus images more appropriately. Transferring the weights from the pre-trained model resulted in faster and easier training than training the network from scratch. In this paper, a dense convolutional neural network (Densenet201) has been utilized to extract the relevant features for classification. Training with 80% of the images and testing with 20% of the images has been performed. The performance metrics obtained by various classifiers such as softmax, support vector machine (SVM), knearest neighbor (KNN), and Naive Bayes (NB) have been compared. Experimental results have shown that the softmax classifier outperformed the other classifiers with 96.48% accuracy, 98.88% sensitivity, 92.1% specificity, 95.82% precision, and 97.28% F1-score, with DRISHTI-GS1 database. An increase in the classification accuracy of about 1% has been achieved with enhanced fundus images

Renyi entropy based Bi-histogram equalization for contrast enhancement of MRI brain images

5-11The quality of the MRI brain images is dependent on the sensor. It is essential to have a pre-processing technique to meet the finest quality at the sensor’s cost. A pre-processing algorithm has been proposed in this paper to enhance the low contrast MRI brain images. The input image’s histogram has been divided into two sub histograms using its median value to uphold the input image’s mean brightness. After calculating the Renyi entropy from the sub histogram, histogram clipping has been done to regulate the enhancement rate. The clipping limit has been selected automatically from the minimum value of the mean, median of the distribution function, and itself. Additionally, the proposed algorithm has incorporated the Discrete Cosine Transform (DCT) to improve the enhancement. Experimental results have shown that the proposed algorithm enhances the input image and maintains the mean brightness

Rheological behavior and printability study of tri-calcium phosphate ceramic inks for direct ink writing method

In the biomedical industry, tricalcium phosphate is a bioceramic substance that is frequently employed in the fabrication of scaffolds and bone structures. Fabrication of porous ceramic structures using conventional manufacturing techniques is very challenging because of the brittle nature of the ceramics, which has led to a newly adapted direct ink writing additive manufacturing method. This work investigates the rheology and extrudability of TCP inks to produce near-net-shape structures. Viscosity and extrudability tests found that stable TCP: Pluronic ink of 50 vol.% was more reliable compared to other tested inks prepared from a functional polymer group polyvinyl alcohol. A line study was carried out to identify the printing parameters suitable for printing structures from the selected ink with lesser dimensional error. Printing speed 5 mm/s and extrusion pressure 3 bar was found suitable to print a scaffold through a nozzle of 0.6 mm, keeping the stand-off distance equal to the nozzle diameter. The printed scaffold was further investigated for its physical and morphological structure of the green body. A suitable drying behavior was studied to remove the green body without cracking and wrapping before the sintering of the scaffold.Web of Science156art. no. 143

Temporal Resolution In Preschool Children

The purpose of this study was to examine temporal resolution in normal hearing pre-school children. Word recognition was evaluated in quiet and in spectrally identical continuous and interrupted noise at signal-to-noise ratios (S/Ns) of 10, 0, and -10 dB. Sixteen children four to five years of age and eight adults participated. Performance decreased with decreasing S/N. At poorer S/Ns, participants demonstrated superior performance or a release from masking in the interrupted noise. Adults performed better than children, yet, the release from masking was equivalent. Collectively these findings are consistent with the notion that preschool children suffer from poorer processing efficiency rather than temporal resolution per se

Sub-clinical diabetic cardiomyopathy - assessment by systolic time intervals

Left ventricular performance in diabetics wit he at hypertension, ischemic Tie art disease, or clinical evidence of other heart diseases was assessed by systolic time intervals and echo-cardiography. The PEP/ LVET ratio was 3.48% higher in diabetics than in controls. There was good correlation of abnormality of PEP/LVET ratio with duration of diabetes. There was no correlation with age of patient or severity of diabetes. There was good correlation between abnormal PEP/LVET and incidence of retinopathy and nephropathy. This suggests the possibility of the presence of subclinical diabetic cardiomyopathy in these individuals