1,851 research outputs found
Charging/Discharging strategy for electric vehicles based on bi-level programming problem: San Francisco case study
The increasing market share of electric cles (EVs) leads to determine a proper strategy for charging/discharging EV batteries such that rewards of all agents including EV charging stations (EVCSs) and EV owners (EVOs) that participate in charging/discharging EV batteries are anteed. In this study, an economical and technical strategy developed. It focuses on finding proper EVCSs by EVOs determining optimal day-ahead electricity prices traded between all agents such that the rewards of EVCSs and EVOs are met multaneously. This optimal charging/discharging decision making and optimal day-ahead electricity prices are determined by level programming problem (BLPP). The outer level corresponds to the optimization problem of EVCSs and the inner level belongs to EVOs. Salp swarm optimization (SSO) algorithm is utilized to solve BLPP. Based on determination of minimum distance travelled by EVOs and optimal day-ahead electricity prices offered by EVCSs, the rewards of EVCSs and EVOs are analysed during charging/discharging period. For simulation purposes, case study based on San Francisco in US is presented to visualize and validate the modelling results. Six EVCSs are installed in Francisco for charging/discharging 247 EVs during 24 hours of typical day. Simulation results show that under implementing proposed charging/discharging strategy, the total cost of EVOs decreases by 17.8% and total revenue of EVCSs increases 18.2%, in comparison with not considering the proposed strategy
Dielectric Properties and AC conductivity of (Epoxy / Ion exchange) blend
The dielectric behavior of blend materials epoxy resin- Polyvinyl benzyl dimethyl ethanol ammonium chloride (PBDEAC) (Ion exchange) was analysed as a function of Ion exchange weight content; temperature and frequency. Blends were prepared by mixing the components and pouring them into suitable moulds. The dielectric parameters have been measured using parallel plate capacitor method in the frequency range from 120 Hz to 2 MHz and in the temperature range from 30 ?C to 110?C. Variations of real (??) and imaginary (?") parts of dielectric constants and loss tangent of material with frequency and temperature have been studied. The experimental results showed that (??) and (?") increased with the addition of Ion exchange filler content. The value of (??) decreased with increasing frequency, which indicates that the major contribution to the polarization comes from orientation polarization. Dielectric loss peaks were also observed in the composite materials at high temperature. The value of (??) increased with increasing temperature, and is due to greater freedom of movement of the dipole molecular chains within the polymer at high temperature. Ac. conductivity and impedance of the composites behaviours as function of frequency and temperature have also been investigated. Keywords: Dielectric properties, epoxy, Ion exchange, ac. conductivity
Numerical Analysis of Friction Stir Welding on an Alumunium Butt Joint
In this paper, we present a three-dimensional numerical analysis of friction stir welding on an alumunium butt joint. A thin sheet of aluminum marking material was embedded into the 6061-aluminum alloy panel and its rear weld path. The positions after friction stir welding were investigated by metallographic techniques. Looking at the visualized material flow pattern, a three-dimensional model was developed to numerically simulate the temperature profile and plastic effects. The calculated velocity profile for plastic flow in the immediate vicinity of the tool generally agrees with the visualized results. Increasing the tool speed while maintaining a constant tool feed rate increases the material flow near the pin. The shape and size of the predicted weld zone match the experimentally measured ones
Experimental investigations of Synchronization in two optically coupled chaotic systems utilizing optical feedback and optical injection
An experimentally observations of chaos synchronization have been investigated between two optically coupled laser diodes. Two schemes of optical injection, bidirectional and unidirectional optical injections have been used. One of the two lasers MLD exhibits optical chaos due to external optical feedback by fiber mirror and the other laser diode SLD exhibits optical chaos by optical injection from the first one. The chaotic dynamics of both lasers were a function of laser diodes drive current. Synchronization and Anti-synchronization between two coupled laser diodes have been observed, and ensured by different measurements like time series matching ,correlation diagram(phase form)of amplitudes of coupled chaotic signals ,spectrum components coinciding of coupled chaotic signals, and coherence have been used for both injection schemes
Attractor selection in semiconductor laser chaos generated by optoelectronic feedback
In this paper, an experimental and numerical study for the evolution of the non-linear dynamics of semiconductor laser has been done under two conditions, when the dc bias current of Semiconductor laser is varied, and when the feedback strength is varied. These dynamics were analyzed by time series and their extracted(FFT) power spectrums, phase diagrams (attractors),inter-spike intervals(ISI), these measurements enhanced by bifurcation diagram which explained the chaotic regimes. The stability states using different control parameters have been demonstrated. The role of control parameters of laser such as: dc bias current and feedback strength is proved in spiking generation and chaos control in the laser output
Heating Effects of Microwave Radiation on Disposable Materials in the Presence of Various Soaking Media
The ability of various soaking media in enhancing the temperature of waste materials, once they are exposed to microwaves has been investigated. Such information helps development of microwave techniques to destroy viruses, spores and other microorganisms by temperature enhancement if they may not be affected by microwave radiation itself. Oily media were observed to have higher elevation in temperature; however, they have the inherent drawback of sticking into the inner surface of the container. Such drawbacks can be minimized by using enclosed non-stick container for the microwave application. Among aqueous fluids, commonly found detergent solution showed the best performance in raising the temperature. Such material has many other advantages such as, low cost, non-toxic nature, environment friendliness, ready availability etc
Heating Effects of Microwave Radiation on Disposable Materials in the Presence of Various Soaking Media
The ability of various soaking media in enhancing the temperature of waste materials, once they are exposed to microwaves has been investigated. Such information helps development of microwave techniques to destroy viruses, spores and other microorganisms by temperature enhancement if they may not be affected by microwave radiation itself. Oily media were observed to have higher elevation in temperature; however, they have the inherent drawback of sticking into the inner surface of the container. Such drawbacks can be minimized by using enclosed non-stick container for the microwave application. Among aqueous fluids, commonly found detergent solution showed the best performance in raising the temperature. Such material has many other advantages such as, low cost, non-toxic nature, environment friendliness, ready availability etc
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