Powering Mobile Networks with Optimal Green Energy for Sustainable Development

Green wireless networking is an emerging area for many societies, especially academia and industry, in light of economic and ecological perspectives. Empowering wireless infrastructures exploiting green power sources can enhance sustainability due to the adverse effects of conventional power sources and atmospheric circumstances. Moreover, the specific power supply requirements for a base station (BS), such as cost effectiveness, efficiency, sustainability, and reliability, can be met by utilizing technological advances in renewable energy. Numerous drivers and motivators are involved in the deployment of renewable energy technologies and the transition toward green energy. Renewable energy is free, clean, and abundant in most locations throughout the year. In this work, a sustainable optimal stand-alone solar-powered model envisioning green cellular BSs for urban locations in Oman is proposed. This model can extend 24 h uninterrupted power supply support to a cellular BS that fully utilizes an integrated storage device. The system analysis is conducted using a hybrid optimization model for electric renewables (HOMER) based on actual prevailing conditions of the regions and their technical feasibility. The results showed can be achieved operational expenditure savings up to 16%. These outcomes provide a huge benefit to the cellular operators of Oman economically, technically, and ecologically.     

Inlet conditions effects on vertical wall jets in forced and mixed convection regimes

In this paper a numerical investigation of a laminar isothermal or nonisothermal two dimensional plane wall jet is carried out. Special attention has been paid to the effect of the inlet conditions at the nozzle exit on the hydrodynamic and thermal characteristics of the flow, in both convection regimes: forced and mixed. Two velocities profiles at the nozzle exit are used: uniform profile and parabolic profile. The Prandtl number effect on the jet flow characteristics is also analyzed in the case of forced convection regime.The system of governing equations is solved with an implicit finite difference scheme. For numerical stability we use a staggered non-uniform grid. The obtained results show, for the two convection modes, that the inlet conditions affect the flow in the immediate neighbourhood of the nozzle (core region) in which the flow is governed mainly by the inertia forces. In the established region the results become independent of the flow inlet conditions. Secondly, the effect of the Prandtl number is significant in the plume region in which the jet flow is governed by buoyant forces.     

Attachment of flame chemielectrons to inert,fine particles

Micron size alumina particles were introduced into low pressure methane-air flat flames on a matrix burner. By means of electrostatic probes the concentrations of chemiions were measured and also the number of electrons attaching to the particles at different positions in the flame, for different particle concentrations. The maximum number of electrons so attached seems larger than that to be expected from a steady state analysis in which electrons and positive ion currents to a particle are equal. Quite small concentrations of particles can be effective in removing electrons from the gas phase. Because the particles are charged, they are efficiently removed by collector anodes at quite moderate voltages.     

Novel integrations of molten salt cavity tubular solar central receiver with existing gas-fuelled conventional steam power plants

This paper introduces a new method to integrate the existing equipment of the AL-Hartha steam plant located in Basra, Iraq, using a molten salt cavity tubular solar central receiver (SCR). Cycle Tempo is used to simulate the existing natural gas-fuelled conventional steam power cycle with consideration of the heat and pressure losses. The heliostat field and the central receiver subsystems are coded using MATLAB. The model couples the heat balance with the temperature computation of the receiver walls for calculation and analysis of the thermal losses. The proposed modified codes are capable of calculating heat losses, evaluating the integrated power plant and satisfying a wide range of SCRs. The results are verified against plant data and previous works in the literature and good agreement is obtained. The results show the potential of using a molten salt cavity tubular for low-range temperature to integrate the economizer (EN) and air preheater, as well as the optimum scheme for the integration of the existing plant with an SCR. It is observed that the best improvement for the existing AL-Hartha steam plant and the integrated molten salt cavity tubular SCR can be achieved by integrating EN, and there is about 9.1% saving in gas fuel consumption.     

Demonstration of synaptic and resistive switching characteristics in W/TiO2/HfO2/TaN memristor crossbar array for bioinspired neuromorphic computing

In this study,resistive random-access memory (RRAM)-based crossbar arrays with a memristor W/TiO2/HfO2/TaN structure were fabricated through atomic layer deposi...     

Protectin DX, a Double Lipoxygenase Product of DHA, Inhibits Both ROS Production in Human Neutrophils and Cyclooxygenase Activities

Neutrophils play a major role in inflammation by releasing large amounts of reactive oxygen species (ROS) produced by NADPH oxidase (NOX) and myeloperoxidase (MPO). This ROS overproduction is mediated by phosphorylation of the NOX subunits in an uncontrolled manner. Therefore, targeting neutrophil subunits would represent a promising strategy to moderate NOX activity, lower ROS, and other inflammatory agents, such as cytokines and leukotrienes, produced by neutrophils. For this purpose, we investigated the effects of protectin DX (PDX)—a docosahexaenoic acid di-hydroxylated product which inhibits blood platelet aggregation—on neutrophil activation in vitro. We found that PDX decreases ROS production, inhibits NOX activation and MPO release from neutrophils. We also confirm, that PDX is an anti-aggregatory and anti-inflammatory agent by inhibiting both cyclooxygenase-1 and -2 (COX-1 and COX-2, E.C. 1.14.99.1) as well as COX-2 in lipopolysaccharides-treated human neutrophils. However, PDX has no effect on the 5-lipoxygenase pathway that produces the chemotactic agent leukotriene B₄ (LTB₄). Taken together, our results suggest that PDX could be a protective agent against neutrophil invasion in chronic inflammatory diseases.     

A Survey and Systematic Categorization of Parallel K-Means and Fuzzy-C-Means Algorithms

Parallel processing has turned into one of the emerging fields of machine learning due to providing consistent work by performing several tasks simultaneously,enhancing reliability (the presence of more than one device ensures the workflow even if some devices disrupted), saving processing time and introducinglow cost and high-performance computation units. This research study presents a survey of parallel K-means and Fuzzy-c-means clustering algorithmsbased on their implementations in parallel environments such as Hadoop, MapReduce, Graphical Processing Units, and multi-core systems. Additionally,the enhancement in parallel clustering algorithms is investigated as hybrid approaches in which K-means and Fuzzy-c-means clustering algorithms areintegrated with metaheuristic and other traditional algorithms.     

A Temperature Compensated CMOS Ring Oscillator for Wireless Sensing Applications

This paper presents a CMOS voltage controlled ring oscillator (VCO) with temperature compensation circuit suitable for low-cost and low-power MEMS gas sensor. This compensated ring oscillator is dedicated to Chopper Stabilized CMOS Amplifier (CHS-A). To operate at low frequency, a control voltage generated by a CMOS bandgap reference (BGR) is described and the measurement results of the fabricated chips are presented. The output voltage of the reference is set by resistive subdivision. In order to achieve small area and low power consumption, n-well resistors are used. This design features a reference voltage of 1 V. The chip is fabricated in AMS 0.35 μm CMOS process with an area of 0.032 mm². Operating at 1.25 V, the output frequency is within 200?±?l0 kHz over the temperature range of ?25 °C to 80 °C with power consumption of 810 μW.     

Modeling, Analysis, and Neural Network Control of an EV Electrical Differential

This paper presents system modeling, analysis, and simulation of an electric vehicle (EV) with two independent rear wheel drives. The traction control system is designed to guarantee the EV dynamics and stability when there are no differential gears. Using two in-wheel electric motors makes it possible to have torque and speed control in each wheel. This control level improves EV stability and safety. The proposed traction control system uses the vehicle speed, which is different from wheel speed characterized by a slip in the driving mode, as an input. In this case, a generalized neural network algorithm is proposed to estimate the vehicle speed. The analysis and simulations lead to the conclusion that the proposed system is feasible. Simulation results on a test vehicle propelled by two 37-kW induction motors showed that the proposed control approach operates satisfactorily.     

Adaptive vectorial lifting concept for convolutive blind source separation

This paper describes a new multi-resolution approach for the blind separation of convolutive image mixtures in transform domain. The proposed method uses an Adaptive Vectorial case of Quincunx Lifting Scheme (AVQLS), based on wavelet decomposition, and a geometric unmixing algorithm. It proceeds in three steps: first, the mixed images are decomposed by AVQLS. Then, the unmixing algorithm is applied to the more relevant component to get a transformed estimate of the original images. An inverse transform is, thereafter, applied to obtain an estimate of the original images. Experiments carried out on medical images showed that the proposed method yields better separation results than many widely used blind source separation algorithms.