72 research outputs found
Design, development, and evaluation of a PV_Bio-Gen range extender for an off-road electric vehicle
Transformation from fossil fuels to clean energy is necessary due to the stricter environmental protection policies. Drivetrain hybridization by green energy sources seems to be an appropriate solution in farm applications. However, some constraints are raised, e.g., the low energy density of renewable energy sources and the long recharging time of batteries. Hence, the objective of this work is to suggest an Extended-Range Solar Assist Plug-In Hybrid Electric Tractor (E-RSAPHT) via a combination of a photovoltaic (PV) system and a biogas fuelled engine generator set (Bio-Gen) with a battery pack. Due to multi-power sources, a heuristic control strategy is proposed to split the generated powers while considering the extend daily operation hours. Moreover, some field measurements are conducted to define typical working cycles for farm hybrid vehicle application. Considering these points, the modelling, simulation and development of the E-RSAPHT are presented in this paper. Experimental results showed that the proposed system could improve energy autonomy and fuel efficiency. For typically evaluated toolbars, the operation ranges of the trailer, boom-type sprayer, and water-pump system were extended up to 292, 255, and 320% compared to the base battery-electric tractor, respectively. The conducted investigations illustrate that even for a 2100kg electric farm vehicle, a downsized 4.4kW Bio-Gen allows the hybrid-electric system to supply the power demand compared to the conventional system by using the internal combustion engine
An intelligent energy management strategy for an off-road plug-in hybrid electric tractor based on farm operation recognition
Abstract Due to the growing emergence of vehicle electrification, agricultural tractor developers are launching hybrid powertrains in which energy management strategy (EMS) assumes a prominent role. This work mainly aims at developing an EMS for a plug-in hybrid electric tractor (PHET) to minimise fuel consumption and increase the operating range. The developed off-road PHET power sources are composed of a biogas-fuelled Internal Combustion Engine Generator (Bio-Gen), a photovoltaic system, and a battery pack. To control the power flow among different sources, a two-layer EMS is formulated. In this regard, initially, the farm operating mode is recognised by means of classification of a working cycle's features. Then, a control strategy based on a multi-mode fuzzy logic controller (MFLC) is employed to manage the power flow. At each sequence, the classifier identifies the farm operation condition and accordingly activates the relative mode of the MFLC to meet the requested power from the Bio-Gen. The performance of the proposed EMS has been evaluated based on three real-world typical agricultural working cycles. The results demonstrate the successful performance of the proposed intelligent EMS under farm conditions by maintaining the energy sources' operation in a high-efficiency zone which can lead to the extension of the working range and decrease fuel consumption
Domestic greywater treatment using electrocoagulation-electrooxidation process: optimisation and experimental approaches
A synergistic combination of electrocoagulation-electrooxidation (EC-EO) process was used in the current study to treat domestic greywater. The EC process consisted of an aluminium (Al) anode and an iron (Fe) cathode, and the EO process consisted of titanium with platinum coating mesh (Ti/Pt) as an anode and stainless steel as a cathode. The effect of operative variables, namely current density, pH, EC time and EO time, on the removal of chemical oxygen demand (COD), colour, turbidity, and total organic carbon (TOC) was studied and optimised using Response Surface Methodology (RSM). The results showed that although the pH affected the removal of all studied pollutants, it had more effect on turbidity removal with a contribution of 88.44%, while the current density had the main dominant effect on colour removal with a contribution of 73.59%. It was also found that at optimal operation conditions for a current density of 2.6 A, an initial pH of 4.67, an EC time of 31.67 min, and an EO time of 93.28 min led to a COD, colour, turbidity, and TOC removal rates of 96.1%, 97.5%, 90.9%, and 98%, respectively, which were close to the predicted results. The average operating cost and energy consumption for the removal of COD, colour, turbidity, and TOC were 0.014 /m3 and 0.008 kWh/kg, 0.075 /m3 and 0.079 kWh/kg, respectively
The treatment of printing and packaging wastewater by electrocoagulation– flotation: the simultaneous efficacy of critical parameters and economics
In this work, electrocoagulation–flotation (ECF) following sedimentation was applied as a printing and packaging wastewater treatment using four Al electrodes with a parallel monopolar configuration. A sedimentation process was applied after the ECF as a post-treatment phase to remove large pollutants. The simultaneous efficacy of the operating parameters initial color content (1,843.44–12,156.56 ADMI), initial pH (3.56–10.44), current density (6.02–22.18 mA/cm2), and treatment time (5.62–74.38 min) on color and chemical oxygen demand (COD) removal efficiencies were evaluated alongside processing costs. Response surface methodology (RSM) and central composite design (CCD) optimized these key parameters to achieve the highest removal efficiencies and lowest operating costs. Based on the results analyzed by RSM-CCD, using initial color content of 5,576.38 ADMI, initial pH of 7.29, the current density of 18.49 mA/cm2, and treatment time of 59.76 min as optimum operational conditions can result in 97.8% and 92.1% for color and COD removal efficiencies, respectively. At these optimum conditions, operating costs (OPCs), including electrodes material and energy consumption, were 0.07 US/(kg COD removed). The results confirm ECF-sedimentation as a promising and costeffective tool for the treatment of printing and packaging wastewater
Environmental impacts of hybrid, plug-in hybrid, and battery electric vehicles—what can we learn from life cycle assessment?
The Effects of Reaction Variables on Solution Polymerization of Vinyl Acetate and Molecular Weight of Poly(vinyl alcohol) Using Taguchi Experimental Design
Poly(vinyl acetate) is synthesized via solution polymerization, and then it is converted to poly(vinyl alcohol) by alkaline alcoholysis. The aim of the work study was to investigate statistically the influence of reaction variables in vinyl acetate polymerization, the conversion of this monomer to polymer, degree of branching of acetyl group in poly(vinyl acetate), as well as the molecular weight of poly(vinyl alcohol), using Taguchi experimental design approach. The reaction variables were polymerization time, molar ratio of initiator to monomer, and volume ratio of monomer to solvent. The statistical analysis of variance of the results revealed that all factors have significantly influenced the conversion and degree of branching. Volume ratio of monomer to solvent is the only factor affecting the molecular weight of poly(vinyl alcohol), and has the greatest influence on all responses. By increasing this ratio, the conversion, degree of branching of acetyl group in poly(vinyl acetate), and molecular weight of poly(vinyl alcohol) were increased
Impediments to the formation of intensive care nurses� professional identify
Background: Nurses face challenges regarding professional identify. Being unaware of these challenges and not owning positive professional identify leads to a lack of self-confidence. Thus, nurses face problems in interpersonal communication and lose their attachment to their profession. Few studies have engaged with impediments to forming positive professional identity in relation to intensive care nurses. Objective: The purpose of this study is to investigate the impediments to forming positive professional identity in nurses working in intensive care unit. Research design: In this study, the conventional content analysis method was used in order to obtain the impediments to forming positive professional identities in nurses. Data were collected through 15 semi-structured interviews and 2 focus group interviews from March 2015 to June 2016. Purposive sampling was used and participants were recruited until data saturation was reached; they were then analyzed using the conventional content analysis method. Participants and research context: In total, 24 intensive care unit nurses from one hospital in Northern Iran were selected through purposive sampling. Ethical consideration: This study was approved by the Ethics Committee of Shiraz University of Medical Sciences. Findings: Four main themes of professional identity challenges were extracted from the analysis of the data: neglect of professional status of nursing; distrust of nursing knowledge; unprofessional performance; and low professional attraction. Discussion and conclusion: Nurses stated that the neglect of the professional status of nursing and distrust of nursing knowledge have always been a hindrance in forming a positive professional identity. They also mentioned that unprofessional performance and low professional attraction are the other influencing factors in this regard. Thus, detecting these factors can guide nurses and their managers towards creating positive professional identity, and as a result, will improve their job satisfaction, professional advancement, and durability. © The Author(s) 2018
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