Application of compressed sensing using chirp encoded 3D GRE and MPRAGE sequences

An implementation of Non-Fourier chirp-encoding in 3D Gradient Recalled Echo (GRE), susceptibility-weighted imaging (SWI) and Magnetization Prepared Rapid Gradient Echo (MPRAGE) sequences is presented with compressive sensing reconstruction. 3D GRE and MPRAGE sequences were designed, in which the phase encoding (PE) direction was encoded with spatially selective chirp encoding Radio Frequency (RF) pulses, while the slice and the readout directions were Fourier encoded using gradients. During each excitation along the PE direction, a different spatially-selective RF excitation pulse was used to encode the PE direction with a complete set of unitary chirp encoding basis. Multichannel compressive sensing reconstruction on the undersampled in vivo data demonstrated that images reconstructed from chirp encoded data were able to preserve the spatial resolution better than the Fourier encoding. The mean Structural Similarity (SSIM) across five subjects at the acceleration factor of 6, for chirp encoded MPRAGE was 0.934 compared to 0.912 for Fourier encoded MPRAGE. The implementation of prospective undersampling demonstrated the feasibility of using chirp encoding in clinical practice for accelerated imaging. The minimum intensity projection of the compressive sensing (CS) reconstructed susceptibility weighted images revealed that chirp encoding is able to delineate small vessels better than the Fourier encoding with the SSIM of 0.960 for chirp encoding compared to the SSIM of 0.949 for the Fourier encoding. Improved performance of chirp encoding for CS reconstruction and SWI, along with the feasibility of implementation makes them a practical candidate for clinical MRI scans.     

Stability Analysis of Epidemic Modeling Based on Spatial Correlation for Wireless Sensor Networks

Wireless Personal Communications - In wireless sensor networks (WSNs), the main task of each sensor node is to sense the physical activity and then report it to a remote central monitoring sink...     

Intelligent heart disease prediction in cloud environment through ensembling

Cloud computing is the delivery of on‐demand computing resources. Cloud computing has numerous applications in fields of education, social networking, and medicine. But the benefit of cloud for medical purposes is seamless, particularly because of the enormous data generated by the health care industry. This colossal data can be managed through big data analytics, and hidden patterns can be extracted using machine learning procedures. In particular, the latest issue in the medical domain is the prediction of heart diseases, which can be resolved through culmination of machine learning and cloud computing. Hence, an attempt has been made to propose an intelligent decision support model that can aid medical experts in predicting heart disease based on the historical data of patients. Various machine learning algorithms have been implemented on the heart disease dataset to predict accuracy for heart disease. Naïve Bayes has been selected as an effective model because it provides the highest accuracy of 86.42% followed by AdaBoost and boosted tree. Further, these 3 models are being ensembled, which has increased the overall accuracy to 87.91%. The experimental results have also been evaluated using 10,082 instances that clearly validate the maximum accuracy through ensembling and minimum execution time in cloud environment.     

Intensified and safe ozonolysis of fatty acid methyl esters in liquid CO2 in a continuous reactor

We demonstrate a continuous reactor for performing the ozonolysis of fatty acid methyl esters (FAMEs) using liquid CO₂ as solvent. The fast reaction kinetics allows the use of small‐volume reactors to completely convert the FAMEs, forming secondary ozonides as the primary products. The short residence times also help maximize the yields of the secondary ozonides by minimizing over‐oxidation and the formation of oligomeric products. The liquid CO₂ medium promotes safe reactor operation by providing an essential fraction of overall reactor cooling and by diluting the vapor phase organics. We also demonstrate a continuous stirred reactor for the safe thermal decomposition of the secondary ozonides to their corresponding acids and aldehydes. Using a lumped kinetic model for the thermal decomposition of the ozonolysis products, we estimate activation energy values of 108.6 ± 0.6 kJ mol^?1 for the decomposition of secondary ozonides and 122 ± 3 kJ mol^?1 for the decomposition of the undesired oligomeric species. © 2017 American Institute of Chemical Engineers AIChE J, 63: 2819–2826, 2017     

Corrosion behaviour of a thin section martensitic stainless steel GTA weldment in chloride solutions

A thin section martensitic stainless steel was welded by gas tungsten arc welding and characterized for the microstructure, hardness and corrosion behaviour in chloride solutions. Welds free from defects could be produced by autogenous welding under the optimized welding conditions. The weld metal was over-matched in terms of mechanical properties (hardness, tensile strength). The general corrosion resistance and the passivation behaviour of the weld metal/heat affected zone (HAZ) region were on par with that of the parent material in chloride and sulphuric acid test electrolytes; however, in terms of pitting corrosion resistance, the martensitic-structured weld metal/HAZ region was marginally inferior compared to its parent material.     

Effect of plasma electrolytic oxidation treatment on the corrosion and stress corrosion cracking behaviour of AM50 magnesium alloy

The effect of a silicate-based plasma anodization treatment on the corrosion and stress corrosion cracking behaviour of a cast AM50 magnesium alloy was studied. Electrochemical tests revealed the beneficial effect of the plasma electrolytic oxidation (PEO) in improving the corrosion resistance of the alloy. Although the coating had provided an improved resistance to stress corrosion cracking in this test environment at a nominal strain rate of 10⁻⁶ s⁻¹, it could not completely eliminate the SCC susceptibility of the alloy. Cracking of the coating under conditions of straining was found to be the reason for SCC of PEO-coated alloy.     

PF-ID-2PAKA: Pairing Free Identity-Based Two-Party Authenticated Key Agreement Protocol for Wireless Sensor Networks

Wireless Personal Communications - To ensure secure communication between any two entities, authenticated key agreement protocol is the primary step and current research has a lot of contribution...     

Biosorption of Cr(VI) by immobilized biomass of two indigenous strains of cyanobacteria isolated from metal contaminated soil

Biosorption of Cr(VI) using native strains of cyanobacteria from metal contaminated soil in the premises of textile mill has been reported in this paper. Biosorption was studied as a function of pH (1-5), contact time (5-180 min) and initial chromium ion concentration (5-20mg/l) to find out the maximum biosorption capacity of alginate immobilized Nostoc calcicola HH-12 and Chroococcus sp. HH-11. The optimum conditions for Cr(VI) biosorption are almost same for the two strains (pH 3-4, contact time 30 min and initial chromium concentration of 20mg/l) however, the biomass of Chroococcus sp. HH-11 was found to be more suitable for the development of an efficient biosorbent for the removal of Cr(VI) from wastewater, as it showed higher values of q(m) and K(f), the Langmuir and Freundlich isotherm parameters. Both the isotherm models were suitable for describing the biosorption of Cr(VI) by the cyanobacterial biosorbents.     

Modified falex testing: A tool for understanding the compound layer capabilities

The usefulness of Falex testing in assessing the scuffing resistance of nitrocarburized steel was established by carrying out tests on treated medium-carbon and hot-working steel specimens. Though the test could be employed as a quality control measure for the compound layer thickness, it was found inadequate in bringing out the subtle variations in the compound layer characteristics of specimens of different steels. By a modified form of Falex testing, the heat resisting ability of the compound layer of different steels could be distinctly brought out.