A new three-point sixth-order THAGE iteration method for mildly nonlinear two-point boundary value problems with engineering applications

We study a new sixth-order compact discretization using uniform three-grid point for the mildly nonlinear differential equation \(\phi ''=g(t,\phi )\), subject to the values of ϕ given at two end points of the regular solution interval. We also discuss three-step AGE (THAGE) iteration method as an application to the resulting difference equation as a powerful numerical computation device. In this algorithm, the common term is evaluated first to save the CPU time in comparison with the corresponding two-step algorithm. In addition, the error analysis is studied. Numerical performance is compared with the exact solution, and with the two-step AGE and SOR iteration methods.

     

Effect of leakage current and dielectric constant on single and double layer oxides in MOS structure

MOS structure of Al/Al₂O₃/n-Si, Al/TiO₂/n-Si and Al/Al₂O₃/TiO₂/n-Si was obtained by deposition of Al₂O₃ and TiO₂ on silicon substrate by RF Magnetron Sputtering system. The total thickness of the oxide layer ~ 40 ± 5 nm in the MOS structure was kept constant. Samples were characterized by X-Ray diffraction (XRD), X-Ray photoelectron spectroscopy (XPS), Impedance analyzer and Current-voltage (J-V) characteristics. The variations in the dielectric constant and tan δ of the MOS capacitor in the frequency range of 1000Hz-1MHz were measured by impedance analyzer. The variation in dielectric constant of the Al/Al₂O₃/TiO₂/n-Si multilayer compared to single layer of Al/Al₂O₃/n-Si and Al/TiO₂/n-Si is due to high probability of defects, lattice mismatch and interface interactions. The steep rise of Tan δ values in the Al/Al₂O₃/TiO₂/n-Si structure is due to the resonance effect of both Al₂O₃ and TiO₂ layers. The leakage current mechanisms of MOS structures were extracted from Schottky coefficient and Poole-Frenkel coefficient. Theoretical values of Schottky coefficients (β_SC) and Poole-Frenkel coefficients (β_PF) for each sample were estimated using the real part of the dielectric constant. The experimental values were calculated from J-V characteristics and compared with theoretical values. The appropriate model has been proposed. It was found that Schottky and Poole-Frenkel mechanisms are applicable at low and high field respectively for all MOS structures. The combination of Al/Al₂O₃/TiO₂/n-Si is found to be a promising structure with high dielectric constant and low leakage current suitable for MOS devices.     

Dyeing of sericin-modified cotton with reactive dyes

In this paper, a new air-jet weft-insertion system, which does not require any air-guide, such as a confusor or profiled reed, is discussed. Characteristics of the new double-holed relay nozzles, studied by using Pitote-tube measurement and Schlieren photography, are presented. The results of air-velocity and turbulence profiles measured by using a Laser Doppler Anemometer (LDA) are reported. The tensions developed in a stationary yarn are also studied.

Schlieren photography and Pitote-tube measurements show that, in many nozzles, the jets are either divergent or parallel with an angular lift Measurements indicate that the air velocity near the jet axis in the weft-insertion direction is much less, with the vertical component of the air velocity accounting for more than one-third of it, and that the main nozzle imparts a higher tension to stationary yarn than the relay nozzles.     

A facile and feasible method to evaluate and control the quality of Jatropha curcus L. seed oil for biodiesel feedstock: Gas chromatographic fingerprint

To establish a facile and feasible method to evaluate and control the quality of Jatropha curcus L. seed oil for biodiesel feedstock, Gas chromatographic (GC) fingerprint technology was introduced and employed. Initially, the chromatograms of the 13 oil samples from various plantation zones in Guizhou, China were obtained under optimized GC conditions. Ten common peaks were selected as the characteristic peaks for chemometrics, seven of which were identified and quantified by comparing with the standards. The mean chromatogram of S7 (n = 3) was selected as the reference spectrum for similarity analysis based on the influence of the fatty acid composition of the raw material on the fuel properties of resulting biodiesel. Furthermore, the result of SA was confirmed by hierarchical clustering analysis and principal component analysis. By this method, all samples can be classified into three groups. The similarity value of samples approaching 1.000 compared with sample 7 was indicative of the desired fuel properties of biodiesel, indicating the potential practical applications in the quality evaluation and control of biodiesel feedstock.     

Uranium biomineralization by a metal resistant Pseudomonas aeruginosa strain isolated from contaminated mine waste

Uranium biomineralization by a metal-resistant Pseudomonas aeruginosa strain isolated from uranium mine waste was characterized for its potential in bioremediation. Uranium resistance, its cellular localization and chemical nature of uranium-bacteria interaction were elucidated. Survival and uranium biomineralization from mine water were investigated using microcosm experiments. The selected bacterium showed U resistance and accumulation (maximum of 275 mg U g(-1)cell dry wt.) following incubation in 100 mg U L(-1), pH 4.0, for 6 h. Transmission electron microscopy and X-ray diffraction analyses revealed that bioaccumulated uranium was deposited within the cell envelope as needle shaped U-phosphate compounds that attain crystallinity only at pH 4.0. A synergistic involvement of deprotonated phosphate and carboxyl moieties in facilitating bioprecipitation of uranium was evident from FTIR analysis. Based on these findings we attribute the localized U sequestration by this bacterium as innocuous complex to its possible mechanism of uranium resistance. Microcosm data confirmed that the strain can remove soluble uranium (99%) and sequester it as U oxide and phosphate minerals while maintaining its viability. The study showed that indigenous bacteria from contaminated site that can survive uranium and other heavy metal toxicity and sequester soluble uranium as biominerals could play important role in uranium bioremediation.     

Vectorized 3D microstructure for finite element simulations

Microstructure based forming models using statistically representative microstructural input provide the most accurate predictions for early localization and failure during complex forming operations. However, the sheer size and complexity of the three dimensional (3D) microstructural data from real materials makes it hard to implement that data in current finite element models. In this report, a technique to create a vectorized 3D microstructure suitable for input into finite element codes is developed and applied to represent the distribution of particles of different phases found in continuous cast (CC) AA5754 sheets, which tend to have heterogeneous particle distributions with particles of several phases in different shapes and sizes (from 0.2 μm to 10 μm) and distributed at random, in stringers and along the “centerline”. The technique consists of a 3D reconstruction of the true microstructure by performing serial sections and conversion of the 3D raster image to the vector image. A 3D mesh is generated automatically using Unigraphics and Hypermesh from real particle field measurements, which can be imported to any FE code. The vectorized microstructure is validated by comparison with the reconstructed images of particle distribution data.     

Analyzing Some Elements of Technological Singularity Using Regression Methods

Technological advancement has contributed immensely to human life and society. Technologies like industrial robots, artificial intelligence, and machine learning are advancing at a rapid pace. While the evolution of Artificial Intelligence has contributed significantly to the development of personal assistants, automated drones, smart home devices, etc., it has also raised questions about the much-anticipated point in the future where machines may develop intelligence that may be equal to or greater than humans, a term that is popularly known as Technological Singularity. Although technological singularity promises great benefits, past research works on Artificial Intelligence (AI) systems going rogue highlight the downside of Technological Singularity and assert that it may lead to catastrophic effects. Thus, there is a need to identify factors that contribute to technological advancement and may ultimately lead to Technological Singularity in the future. In this paper, we identify factors such as Number of scientific publications in Artificial Intelligence, Number of scientific publications in Machine Learning, Dynamic RAM (Random Access Memory) Price, Number of Transistors, and Speed of Computers’ Processors, and analyze their effects on Technological Singularity using Regression methods (Multiple Linear Regression and Simple Linear Regression). The predictive ability of the models has been validated using PRESS and k-fold cross-validation. Our study shows that academic advancement in AI and ML and Dynamic RAM prices contribute significantly to Technological Singularity. Investigating the factors would help researchers and industry experts comprehend what leads to Technological Singularity and, if needed, how to prevent undesirable outcomes.     

Steganalysis for clustering modification directions steganography

Multimedia Tools and Applications - In recent time, most of the steganographic methods minimize the embedding cost while maximizing the embedding capacity by injecting message bits in the highly...     

Child–smartphone interaction: relevance and positive and negative implications

Universal Access in the Information Society - An increasing number of children are now using smartphones, and the phenomenon is being studied keenly by computer scientists, pediatricians,...