Designing a wind energy harvester for connected vehicles in green cities

Electric vehicles (EVs) have recently gained momentum as an integral part of the Internet of Vehicles (IoV) when authorities started expanding their low emission zones (LEZs) in an effort to build green cities with low carbon footprints. Energy is one of the key requirements of EVs, not only to support the smooth and sustainable operation of EVs, but also to ensure connectivity between the vehicle and the infrastructure in the critical times such as disaster recovery operation. In this context, renewable energy sources (such as wind energy) have an important role to play in the automobile sector towards designing energy-harvesting electric vehicles (EH-EV) to mitigate energy reliance on the national grid. In this article, a novel approach is presented to harness energy from a small-scale wind turbine due to vehicle mobility to support the communication primitives in electric vehicles which enable plenty of IoV use cases. The harvested power is then processed through a regulation circuitry to consequently achieve the desired power supply for the end load (i.e., battery or super capacitor). The suitable orientation for optimum conversion efficiency is proposed through ANSYS-based aerodynamics analysis. The voltage-induced by the DC generator is 35 V under the no-load condition while it is 25 V at a rated current of 6.9 A at full-load, yielding a supply of 100 W (on constant voltage) at a speed of 90 mph for nominal battery charging

Development and Comparative Analysis of Electrochemically Etched Tungsten Tips for Quartz Tuning Fork Sensor

Quartz Tuning Fork (QTF) based sensors are used for Scanning Probe Microscopes (SPM), in particular for near-field scanning optical microscopy. Highly sharp Tungsten (W) tips with larger cone angles and less tip diameter are critical for SPM instead of platinum and iridium (Pt/Ir) tips due to their high-quality factor, conductivity, mechanical stability, durability and production at low cost. Tungsten is chosen for its ease of electrochemical etching, yielding high-aspect ratio, sharp tips with tens of nanometer end diameters, while using simple etching circuits and basic electrolyte chemistry. Moreover, the resolution of the SPM images is observed to be associated with the cone angle of the SPM tip, therefore Atomic-Resolution Imaging is obtained with greater cone angles. Here, the goal is to chemically etch W to the smallest possible tip apex diameters. Tips with greater cone angles are produced by the custom etching procedures, which have proved superior in producing high quality tips. Though various methods are developed for the electrochemical etching of W wire, with a range of applications from scanning tunneling microscopy (SPM) to electron sources of scanning electron microscopes, but the basic chemical etching methods need to be optimized for reproducibility, controlling cone angle and tip sharpness that causes problems for the end users. In this research work, comprehensive experiments are carried out for the production of tips from 0.4 mm tungsten wire by three different electrochemical etching techniques, that is, Alternating Current (AC) etching, Meniscus etching and Direct Current (DC) etching. Consequently, sharp and high cone angle tips are obtained with required properties where the results of the W etching are analyzed, with optical microscope, and then with field emission scanning electron microscopy (FE-SEM). Similarly, effects of varying applied voltages and concentration of NaOH solution with comparison among the produced tips are investigated by measuring their cone angle and tip diameter. Moreover, oxidation and impurities, that is, removal of contamination and etching parameters are also studied in this research work. A method has been tested to minimize the oxidation on the surface and the tips were characterized with scanning electron microscope (SEM)

An experimental and DFT study on novel dyes incorporated with natural dyes on titanium dioxide (TiO2) towards solar cell application

Titanium dioxide (TiO2) thin flms were deposited on fuorine tin oxide (FTO) coated glass substrate using spin-coating techniques and as-deposited flms were sensitized with various dyes. A series of azo derivatives (2, 5a-b) having diferent structures were successfully prepared through the process of the azo coupling reaction. KAZO 6 was successfully synthesized by esterifcation of kojic acid obtained from sago waste with azo 5a. These azo dye were examined using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) to obtain the vertical excitation, electron distribution, energy levels, band gap, and light-harvesting efciency in the ground and excited state. The obtained values exhibited a good correlation with the experimental values. Efciency enhancement was reported by the incorporation of KAZO 6 with curcumin extracted from turmeric. Spectroscopy and optical properties of synthesized dyes were characterized using CHNS elemental analysis, FTIR, 1 H NMR, 13C NMR, and UV–Vis spectroscopies. KAZO 6 displayed an efciency of 1.59% compared to azo derivatives 0.13–1.12%. The efciency of KAZO 6 enhanced from 1.59 to 1.74% with the incorporation of turmeric dye

Architecture for Collision-Free Communication Using Relaxation Technique

In today’s world we are surrounded by world of smart handheld devices like smart phones, tablets, netbooks, and others. These devices are based on advance technologies of multiple-input and multiple-output, Orthogonal Frequency Division Multiplexing (OFDM), and advance data reliability techniques such as forward error corrections. High data rates are among the requirements of these technologies for which turbo and low density parity check codes (LDPC) are widely used in these standards. In order to get high speed, we need multiple and parallel processors for the implementation of such codes. But there exists a collision problem as a consequence of parallel processor. This problem results in increase latency and increase of hardware complexity. In this work an approach for collision problem is presented in which network relaxation technique is used which is based on a fast clique detection. The proposed approach results in high throughput in terms of latency and complexity. Furthermore, the proposed solution is able to solve the collision problem by connecting network optimization for achieving high throughput

Moment Generating Function Based Performance Analysis of Network Coding Two-way Relaying Using Alamouti Scheme on Fading Channels

Abstract- This article discusses the performance analysis of a network coded relay network. The relay nodes operate in decode-and-forward (DF) mode. The channels are modeled as Rayleigh, Nakagami-m and Rician fading. The overall system performance is improved by using the Alamouti coding scheme. The closed-form expressions of m o m e n t generating function (MGF) are obtained over various fading channels. The system performance is analyzed in terms of SER and outage probability. MGF based approach is followed to derive the closed-form expressions of SER for MPSK modulation schemes. The derived expressions also present the diversity order. The simulation and theoretical results are produced to authenticate accuracy of the system

Hydromagnetic mixed convective flow over a wall with variable thickness and Cattaneo-Christov heat flux model: OHAM analysis

The effect of Cattaneo-Christov heat flux model for the hydro-magnetic mixed convective flow of a non-Newtonian fluid is presented. The flow over a wall having variable thickness is anticipated under the influence of transverse magnetic field and internal heat generation/absorption effects. Mathematical formulation has been performed by making use of the suitable transformations. Convergence analysis has been performed and the optimal values are computed by employing optimal homotopy analysis method. The effects of physical parameters are elaborated in depth via graphical and numerical illustrations. Keywords: Cattaneo-Christov heat flux model, OHAM analysis, Mixed convection, Internal heat generation/absorptio

Adaptive Global Fast Sliding Mode Control for Steer-by-Wire System Road Vehicles

A steer-by-wire (SbW) system, also known as a next-generation steering system, is one of the core elements of autonomous driving technology. Navigating a SbW system road vehicle in varying driving conditions requires an adaptive and robust control scheme to effectively compensate for the uncertain parameter variations and external disturbances. Therefore, this article proposed an adaptive global fast sliding mode control (AGFSMC) for SbW system vehicles with unknown steering parameters. First, the cooperative adaptive sliding mode observer (ASMO) and Kalman filter (KF) are established to simultaneously estimate the vehicle states and cornering stiffness coefficients. Second, based on the best set of estimated dynamics, the AGFSMC is designed to stabilize the impact of nonlinear tire-road disturbance forces and at the same time to estimate the uncertain SbW system parameters. Due to the robust nature of the proposed scheme, it can not only handle the tire–road variation, but also intelligently adapts to the different driving conditions and ensures that the tracking error and the sliding surface converge asymptotically to zero in a finite time. Finally, simulation results and comparative study with other control techniques validate the excellent performance of the proposed scheme