Model based development of torque control drive for induction motors for micro electric vehicles

Electric vehicles are attaining significant attention recently and the current legislation is forcing the automotive industry to electrify the productions. Regardless of electric energy accumulation technology, drive technology is one of the vital components of EVs. The motor drive technology has been mainly developed based on the application which required position/velocity control. In automotive application, however, torque control is an important aspect since the drivers have already used to drive the vehicle based on torque control approach in traditional powertrain system. In this article, a model-based approach is employed to develop a controller which can guarantee the precise control of the induction motors torque for a micro electric vehicle (EV) application regardless of operating conditions. The implementation of the control drive was conducted in MATLAB/Simulink environment, followed by Model In the Loop simulation and testing at various test conditions to confirm the robustness of the developed drive. Direct Torque Control (DTC) with optimum voltage vector selection method is employed to control the motor torque that requires fewer power electronics to process its operation and hence lowers the cost of implementation. The result shows the practicality of the designed control system and its ability to track reference torque commands. Vitally, the controlled approach shows fair abilities to control IMs to produce torque at both the motoring and regenerative modes which is a highly important requirement in electrical propulsion powertrains. Furthermore, the controller’s response time was within the industrial standard range which confirms its suitability for industrial implementation at low cost

Simulation-based training in Ebola Personal Protective Equipment for healthcare workers: Experience from King Abdulaziz University Hospital in Saudi Arabia

Background: Millions of Muslims from across the world gather annually to perform pilgrimage. This can import unusual communicable diseases such as Ebola. Communicable diseases with a high risk of mortality necessitate special training to master the required competency to avert transmission of infections. The efficacy of simulation-based training (SBT) has been shown in such circumstances. Objective: We sought to develop an SBT program in Ebola Personal Protective Equipment (PPE) for all healthcare workers (HCWs). Methods: We conducted a quasi-experimental study at the clinical skills and simulation center at the King Abdulaziz University. An interdisciplinary committee was formed to develop this program in three stages. Pre-intervention: Needs assessment “Diagnostic drill”; we conducted in-situ simulation in the emergency department (ED). High-fidelity simulator (HFS) was used as a suspected Ebola case to assess HCWs’ competency of PPE. We used a checklist that was developed in accordance with the national and international guidelines. We then conducted “Train the Trainer in Ebola PPE” course to develop potential instructors. Intervention: PPE competency SBT courses. This involved focusing on trainees to be skilled in Ebola PPE and becoming trained observers using skill stations and Ebola scenario with HFS, followed by debriefing. All courses gathered participants’ evaluations, pre, and post-tests. Post-intervention: In-situ simulation in the ED two months later that was similar to the diagnostic drill. Results: Pre-intervention: 7 HCWs were involved in the drill, the average score was 37% of the checklist items. For train the trainer, 19 potential PPE instructors attended the program; of them, 65% were female and 35% male, and 6 were physicians and 13 nurses. Average pre and post-tests scores were 72% and 86%, respectively. Intervention: 10 PPE courses that were attended by 179 HCWs; of them, 67% were female and 33% male, and 52 were physicians, 112 nurses, and 15 others. Pre and posttests were 67% (57–75%) and 85% (81–91%), respectively, with a p-value \u3c 0.01. Post-intervention: Post Program drill\u27s average score was 86% of the checklist items (37% in diagnostic drill). Conclusions: Using SBT could be an effective method of developing competent HCWs in Ebola PPE. © 2018 The Author

Embracing sustainable farming: Unleashing the circular economy potential of second-life EV batteries in agricultural applications

Growing Kent and Medway Members Showcase Day

Techno-economic feasibility of retired electric-vehicle batteries repurpose/reuse in second-life applications: A systematic review

In line with the global target in decarbonising the transportation sector and the noticeable increase of new electric vehicles (EV) owners, concerns are raised regarding the expected quantity of Retired EV Batteries (REVB) exposed to the environment when they reach 70–80% of their original capacity. However, there is significant potential for REVB, after deinstallation, to deliver energy for alternative applications such as storing surplus. This systematic review evaluates state-of-art modelling/experimental studies focused on repurposing REVB in second-life applications. Technical and economic viability of REVB repurposing has been confirmed to solve the unreliability of cleaner energy technologies and mitigate the high investment of new storage systems. 40% of included studies considered hybrid systems with PV being a dominant technology where REVB was evaluated to be small-scaled and large storage systems. Additionally, successful attempts were conducted to evaluate REVB performance in providing grid services. It has however, been discovered intensive grid services applications like frequency regulation, was technically challenging due to demanding working requirements. Reviewed studies considered different prices for REVB due to lack of market regulation on REVB resale; similarly, technical parameters, including initial State of Health (SoH) and State of Charge (SoC) constraints were inconsistent due to lack of standardisation

Micellization Behavior of Ionic Surfactants in Presence of Butanol Isomers in Non-aqueous Solutions

Electrical conductivity and surface tension measurements of various surfactants, such as sodium caprylate, sodium laurate, sodium palmitate and sodium stearate micellar solution,  containing  1-butanol  (1-BuOH),  2-butanol  (2-BuOH)  and tertiary butanol (t-BuOH) in n,n-dimethyl acetamide have been determined at various temperatures. Both methods show that micelles are formed in n,n-dimethyl acetamide  (DMA) solution in the presence of butanol isomers. Critical micelle concentration (cmc) has been determined for each of the surfactants. Critical micelle concentrations have also been measured as a function of temperatures and concentration of butanol isomers added. It is suggested that the addition of alcohol leads to an increase in n,n-dimethyl acetamide penetration into the micellar interface that depends on the alkyl chain configuration for three isomeric alcohols. Thermodynamic parameters of micellization, enthalpy  (ÄH0m,  entropy  (ÄS0m),  and free energy  (ÄG0m)  were determined from the temperature  dependence of  CMC.  The solvent composition dependence of these thermodynamic parameters is determined in terms of the effect of additives on the micellization of ionic surfactants. It is observed that both ÄH0m and ÄS0m bear out not only the observed order of decrease in cmc but also account reasonably the effects produced by differences in alkyl chain configuration for these isomeric alcohols. In all cases ÄG0m < 0, and remained practically constant over the entire solvent composition range studied.  It is suggested that due to different structural consequences of intermolecular interactions,  both enthalpy and entropy must differ in a  mutually compensating manner so that G0m is not significantly affected

The Shakespearean Poetic Rosary: The ‘Sacred Numbers’ in Shakespeare’s Sonnets

In human culture there are certain numbers of special importance. They are mostly used in old and modern writings as “sacred numbers” of religious and literary significance. They are present in the Greek myths, in Egyptian Pharaonic culture, in ancient Persian, in the Indian culture, and in Arab traditions; then (Islamic) culture as well as in the Biblical Western culture. These numbers are of two kinds: even and uneven or odd. The odd numbers 1, 3, 5, 7and 9 play a far more important part than the even numbers. One is Deity, three the Trinity, five the chief division, seven is the sacred number, and nine is three times three. These numbers have good function and been looked at as ‘Sacred’ or ‘Perfect’ numbers either of good omen or evil. There is another forth number, which is “10”, it comes mainly in Jewish and Islamic education in very few cases having similar religious suggestion. Shakespeare has used the number Ten in Sonnet 6 Then let not winter's ragged hand deface. “Sacred Numbers” have become a part of religion and even of modern belief, and mostly represented in the popular rituals. Shakespeare has used the “Sacred Numbers” in his works either prose or poetry, and this article is restricted to deal only with three Shakespearean sonnets where I imagine Shakespeare reciting his Latin Rosary in a poetic religious tone and drawing the cross sign on his chest and on the forehead of his sonnets in order to invoke divine protection. It seems that Shakespeare’s date of birth and death (1564 -1616) carries a certain secret of his fondness for sacred numbers; thus: The sum of the date of his birth (1564=16) is doubled in the date of his death (1616)

Thermodynamics of Dissociation and Micellization of Sodium Surfactant Solutions in Formamide

Electrical conductivity and surface tension measurement of sodium surfactants, such as sodium caprylate, sodium laurate, sodium palmitate and sodium stearate, in formamide has been determined at different temperatures. The methods show that micelles are formed in formamide solution. Critical micelle concentration (CMC) has been determined for each of the sodium surfactants. The result show that these surfactants behave as a weak electrolyte in dilute solution of formamide below the critical micellar concentration, and the conductance result can be explained on the basis of Ostwald’s formula and Debye–Huckle’s theory of weak electrolytes. The dissociation constant and thermodynamic parameters for dissociation and micellization processes of these surfactants are also evaluated. The micellization process has been found to be predominant over the dissociation process. Keywords: Critical Micelle Concentration (CMC), Micellization, Conductivity, Dissociation, Thermodynamics, Surface Tensio

Soliton-potential interaction in the nonlinear Klein-Gordon model

The interaction of solitons with external potentials in nonlinear Klein-Gordon field theory is investigated using an improved model. The presented model has been constructed with a better approximation for adding the potential to the Lagrangian through the metric of background space-time. The results of the model are compared with another model and the differences are discussed.Comment: 14 pages,8 figure

The impacts of geopolitical risks on the energy sector: Micro-level operative analysis in the European Union

Energy prices play a crucial role in combating geopolitical risks, especially for the major suppliers of energy resources. However, energy prices display a bilateral relationship with geopolitical risks in any economy. Any hike in the price of energy stimulates geopolitical risk factors and visa-versa. The consequences adversely impact economies and bring forth international tensions. This paper bridges a gap between the influence of geopolitical risks relating to energy and international tensions by analyzing micro-level operational measures. We deploy an empirical model to predict the energy sector and possible risk factors incorporating Eurostat data on twenty-seven states, from 2011 to 2020. This study collected a different energy variable to support the multiple regression model constructed by the “blocks” (hierarchical linear regression) method. The results suggest that geopolitical risks cause adverse effects on both the energy and other corporate sectors. The future direction of this research is to estimate how statistical model relationships may assist the corporate sector, and investors, in adopting mitigating measures to control upcoming geopolitical risks due to energy risks caused by geopolitical unrest.info:eu-repo/semantics/publishedVersio