Modification of Harris hawks optimization algorithm with random distribution functions for optimum power flow problem

Neural Computing and Applications - Harris hawks optimization (HHO) algorithm, which is inspired from Harris hawks hunting strategy, uses uniform random numbers in the optimization process. This...     

Recovery of Cobalt,Copper and Zinc from Küre-Kastamonu Historical Copper Slag by High Pressure Oxidative Acid Leaching

Russian Journal of Non-Ferrous Metals - Copper slags are solid by-products formed during the copper production process by pyrometallurgical method from sulfide copper ores. These slags usually...     

Performance study of selective encryption in comparison to full encryption for still visual images

Securing digital images is becoming an important concern in today＇s information security due to the extensive use of secure images that are either transmitted over a network or stored on disks. Image encryption is the most effective way to fulfil confidentiality and protect the privacy of images. Nevertheless, owing to the large size and complex structure of digital images, the computational overhead and processing time needed to carry out full image encryption prove to be limiting factors that inhibit it of being used more heavily in real time. To solve this problem, many recent studies use the selective encryption approach to encrypt significant parts of images with a hope to reduce the eneryption overhead. However, it is necessary to realistically evaluate its performance compared to full encryption. In this paper, we study the performance and efficiency of image segmentation methods used in the selective encryption approach, such as edges and face detection methods, in determining the most important parts of visual images. Experiments were performed to analyse the computational results obtained by selective image encryption compared to full image encryption using symmetric encryption algorithms. Experiment results have proven that the selective encryption approach based on edge and face detection can significantly reduce the time of encrypting still visual images as compared to full encryption. Thus, this approach can be considered a good alternative in the implementation of real-time applications that require adequate security levels.     

Synthesis and morphology analysis of electrospun copper nanowires

We report the fabrication of copper nanowires (NWs) using electrospinning technique. This processing technique was used successfully to synthesize copper NWs with various morphologies using a precursor composed of copper acetate salt and poly(vinyl) alcohol. The obtained NWs were characterized through high resolution scanning electron microscopy and atomic force microscopy and it was found that their morphology is sensitive to the applied voltage and solution flow rate. Their diameter decreased with increasing voltage and increasing flow rate. Moreover, at higher flow rate and lower voltage, the roughness of NWs became more pronounced. In addition, further improvement in NW morphology may be obtained with appropriate heat treatment. These copper NWs with varying morphologies and microstructures have potential applications in different engineering domains such as electronics, optoelectronics, and catalysis.     

On the use of textual feature extraction techniques to support the automated detection of refactoring documentation

Innovations in Systems and Software Engineering - Refactoring is the art of improving the internal structure of a program without altering its external behavior, and it is an important task when it...     

Generalized differential quadrature analysis of electro-magneto-hydrodynamic dissipative flows over a heated Riga plate in the presence of a space-dependent heat source: The case for strong suction effect

The importance of including an electromagnetic actuator as a moving boundary on the dissipative flows of weakly conducting fluids had led to many published facts. But, nothing is known on the generalized differential quadrature analysis of magnetohydrodynamics over a Riga plate with emphasis on the case of viscous dissipation and space-dependent heat source. After deriving the simplified boundary layer equation that models the transport phenomenon, appropriate variables were used to non-dimensionalize and parameterize the partial differential equations. Thereafter, the resulting set of ordinary differential equations was solved numerically by applying a powerful differential quadrature algorithm. Based on the outcome of the simulation, it can be concluded that the viscous frictional effect can be minimized at the Riga plate either by weakening the suction process or by heightening the magnetic parameter. Moreover, the Lorentz forces have a hastening effect on the fluid motion, in the case when those magnetic causes are directed in the same sense of the developed flow.     

Filter orthogonal frequency-division multiplexing scheme based on polar code in underwater acoustic communication with non-Gaussian distribution noise

The research domain of underwater communication has garnered much interest among researchers exploring underwater activities. The underwater environment differs from the terrestrial setting. Some of the main challenges in underwater communication are limited bandwidth, low data rate, propagation delay, and high bit error rate (BER). As such, this study assessed the underwater acoustic (UWA) aspect and explored the expression of error performance based on t-distribution noise. Filter orthogonal frequency-division multiplexing refers to a new waveform candidate that has been adopted in UWA, along with turbo and polar codes. The empirical outcomes demonstrated that the noise did not adhere to Gaussian distribution, whereas the simulation results revealed that the filter applied in orthogonal frequency-division multiplexing could significantly suppress out-of-band emission. Additionally, the performance of the turbo code was superior to that of the polar code by 2 dB at BER 10⁻³.     

Evaluation of the Cytotoxic Behavior of Fungal Extracellular Synthesized Ag Nanoparticles Using Confocal Laser Scanning Microscope

Silver nanoparticles have been synthesized by subjecting a reaction medium to a Fusarium oxysporum biomass at 28 °C for 96 h. The biosynthesized Ag nanoparticles were characterized on the basis of their anticipated peak at 405 nm using UV-Vis-NIR spectroscopy. Structural confirmation was evident from the characteristic X-ray diffraction (XRD) pattern, high-resolution transmission electron Microscopy (HRTEM) and the particle size analyzer. The Ag nanoparticles were of dimension 40 ± 5 nm and spherical in shape. The study mainly focused on using the confocal laser scanning microscope (CLSM) to examine the cytotoxic activities of fungal synthesized Ag nanoparticles on a human breast carcinoma cell line MCF7 cell, which featured remarkable vacuolation, thus indicating a potent cytotoxic activity.