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In this paper, the three-level T-type neutral-point-clamped indirect matrix converter topology and the relative space vector modulation methods are introduced to improve the voltage transfer ratio and output voltage performance. The presented converter topology is based on combinations of cascaded-rectifier and three-level T-type neutral-point-clamp inverter. It can overcome the limitation of voltage transfer ratio of the conventional matrix converter and the high voltage rating of power switches of conventional matrix converter. Two SVPWM strategies for proposed converter are described in this paper to achieve the advantages features such as: sinusoidal input/output currents and three-level output voltage waveforms. Results from Psim 9.0 software simulation are provided to confirm the theoretical analysis. Hence, a laboratory prototype was implemented, and the experimental results are shown to validate the simulation results and to verify the effectiveness of the proposed topology and modulation strategies. [ABSTRACT FROM AUTHOR]

Pulse width modulation strategies have been developed for indirect matrix converters (IMCs) in order to improve their performance. In indirect matrix converters, the LC input filter is used to remove input current harmonics and electromagnetic interference problems. Unfortunately, due to the existence of the input filter, the input power factor is diminished, especially during operation at low voltage outputs. In this paper, a new space vector modulation (SVM) is proposed to compensate for the input power factor of the indirect matrix converter. Both computer simulation and experimental studies through hardware implementation were performed to verify the effectiveness of the proposed modulation strategy. [ABSTRACT FROM AUTHOR]

This letter proposes a novel method to reject $6n \pm 1$ harmonics in the stator voltage at the point of common coupling (PCC) for a stand-alone doubly-fed induction generator (DFIG) supplying a balanced three-phase diode rectifier. These harmonics are rejected by using the rotor current controller in the fundamental synchronous reference frame. The proposed control algorithm is based on a proportional integral controller and a bank of resonant filters. In this frame, each resonant filter in the rotor current controller has the possibility of rejecting one pair of the positive and the negative stator harmonic voltages at the PCC. Experimental results with 2.2-kW DFIG are shown in this letter. [ABSTRACT FROM PUBLISHER]

This article analyses the effects of deformation on the structure of CMnSi steel at various deformation levels. After hot forging, the structure of CMnSi steel comprises coarse-sized alpha and pearlite particles. The average grain size of steel after forging was 100 μm. After hot rolling, the grain size gradually decreases, with the average size of the ferrite and pearlite grains measured as 60 μm. After that, CMnSi steel was subjected to cold deformation at levels of 40%, 60%, and 80%. The grain size of the CMnSi steel sample after 80% cold deformation reached level 7, corresponding to about 25 μm. For a deformation level of 40%, the grain size was level 5, corresponding to 40 μm, while a deformation level of 60% produced a grain size of 35 μm, corresponding to level 6. In addition, scanning electron microscopy showed that after 80% deformation, smaller particles with a size of about 5 μm appear inside the parent particles. Moreover, energy-dispersive X-ray spectroscopy analysis revealed the carbide appearance in the form M23C6, with M being a mixture of Fe and Mn. These carbides have a fine size of about 1–2 μm and contribute to the prevention of particle growth during subsequent heat treatments. [ABSTRACT FROM AUTHOR]

Gaseous-liquid fuel combinations of biogas as primary fuel and diesel as pilot fuel were employed to power a compression ignition (CI) engine in this study. The effects of variable input factors such as engine load, compression ratio, and pilot fuel injection advance on the dual-fuel engine's combustion, thermal, and emission performance were investigated. The data acquired during this lab-based testing was used to develop a prognostic model using a Bayesian optimization strategy for hyperparameter optimization and a contemporary ensemble Gaussian process regression (GPR) technique. During model testing, the error analysis revealed that the developed model could predict the experimental data rather correctly, with R2 values ranging from 0.9995 to 0.9999 and MSE values ranging from 0.00018 to 0.1334. The mean absolute error was discovered to be between 0.0091 and 0.3065. Consequently, the developed GPR model can effectively simulate the on-board performance, emission, and combustion characteristics of a diesel-biogas dual-fuel setting. As a consequence, the current work established the GPR model in the existing CI engine meta-modeling framework as a consistent, trustworthy, and robust system analytical approach for diesel-biogas dual fuel mode of operation. • Waste-derived biogas was used to power the diesel engine in dual-fuel mode. • Gaussian process regression was employed to develop a prognostic model. • Bayesian approach was used for hyper parameter optimization for best results. • Used model could predict emission and performance of the engine with 99.9% accuracy. • A precise metamodel framework to simulate the input–output paradigm was developed. [ABSTRACT FROM AUTHOR]

This paper proposes a decentralized control structure and method for a multilevel single-phase power converter using space vector pulse width modulation (SVPWM). The focus of this paper is on the decentralized control structure for the power converter cells that will exchange information with neighboring cells in order to adjust the switching vector and switching time for each cell. In this study, the switching vectors and the corresponding switching times of each cell will be self-determined based on the phase angle of two neighboring cells. Normally, SVPWM applied to the multilevel power converters need complete information about the total cells and cell's position to build a control algorithm. Meanwhile, a decentralized space vector pulse width modulation (DSVPWM) method is proposed that can be applied to power converters with any number of cells and can be considered as a multilevel SVPWM method. In addition, the decentralized multilevel single-phase power converter has high flexibility with which it is possible to easily adjust the number of active cells, so that the output voltage can be adjusted quickly; this provides the ability to dynamically reconfigure without interrupting the power energy supply process. The proposed control structure and method are effectively verified based on simulation and experimental results. Experimental results are evaluated based on a 9-level single-phase power converter, which has an RL load with rated parameters 220 V/500 W. [ABSTRACT FROM AUTHOR]

Abstract: A new method for the synthesis of nanosized zeolites in organic solvents, such as formamide and toluene as crystallization medium instead of water, in the presence of organosilane has been developed. Organic solvents have a great impact on the synthesis of nanozeolites. Formamide, which has similar properties to water, is a good candidate as the solvent for the synthesis of nanosized zeolites. This synthetic method allows easy manipulation with the control of crystal sizes. In this study, different crystal sizes such as 25, 40 and 100nm were prepared in toluene and formamide solvents. To study the effect of crystal nanosizes on the catalytic performance of nanosized zeolites, nanozeolite-based FCC catalysts were also prepared using different nanozeolite sizes as active component and silica as inactive matrix. The activity of these catalysts was evaluated with FCC feedstock. The results revealed a good correlation between the crystal size of zeolites and the activity: smaller nanozeolite-based FCC catalyst exhibits higher catalytic activity. [Copyright &y& Elsevier]

Developing countries are becoming the factory of the world where sustainable production is still far from developed countries. However, the acceleration of the 4.0 revolution with a close connection with the Internet of Things (IoT) achievements has forced developing countries to integrate with the trend of a circular and sustainable economy. In this paper, the emerging digital technologies of Industry 4.0 which concentration on the contribution of IoT, Virtual Reality, Augmented Reality, and Big Data in remanufacturing are reviewed. Based on IoT, remanufacturing, circular economy, and smart manufacturing, this paper has made the assessment and discussed the challenges and barriers of the 4th industrial revolution to remanufacturing, as well as the amazing opportunities that IoT technologies can contribute to the growth of the remanufacturing industry in developing countries. A value-creation perspective consists of the product which is remanufactured, the equipment and processes of remanufacturing which are adopted and associated with troubles of organization, are used to identify trends and gaps. Suggestions from findings show that it is necessary to detect the combination between cyber-physical systems and the IoT architecture to assistant smart remanufacture, parallel with developing data and infrastructures of communication and circular economy management models. It is clear that, in order to successfully develop the remanufacturing industry, emerging economies need to fully utilize the achievements of IoT technology through economic development strategies and policies in line with Industry 4.0 to create breakthroughs in sustainable circular economy development. [ABSTRACT FROM AUTHOR]

Entering the first decade of the 21st century, researchers on applying modern information technology to controlling ocean environment have made positive progress such as the successful applications of Internet of Things technologies to air and water quality control. In the present work, a comprehensive assessment of the applicability of the emerging technology of the Internet of Things to the control of ocean environmental pollution is conducted. First, the paper focuses on highlighting the applications of the intelligent environment as a premise for concisely analyzing emerging technologies of the Internet of Things including Big data analysis and artificial intelligence in controlling and monitoring the quality and situation of the marine environment. Finally, the challenges and opportunities essential to the field of research were briefly discussed, which is focusing on applications with great prospects of the Internet of Things and the science of Big data analysis in protecting the ocean environment. The advanced IoT-based technologies discussed in this work can be useful summaries and evaluations of information technology applications for managers and enforcers in mitigating negative anthropogenic impacts on the ocean environment. [ABSTRACT FROM AUTHOR]

Low viscous biofuel is one of the alternative sources in the recent past. The focus of this exploration is to assess the engine attributes with low viscous biofuel and to provide a feasible partial substitute with affordable power and reduced emissions. Indeed, Cinnamon oil was extracted from the bark of the Cinnamon tree using the steam distillation technique, and its physicochemical properties were probed as per the ASTM standards. The functional groups and fatty acid composition for the raw and extracted fuel samples were studied using FT-IR and GC-MS analysis. Later, low viscous Cinnamon oil was blended with high viscous Jatropha oil methyl ester (JOME) in the ranges of 70%, 80%, and 90% to form J30C70, J20C80 & J10C90 blends. Without any manual changes, the experiments were conducted on a single-cylinder diesel engine fuelled with J100 (100% JOME) and Cinnamon-blended JOME samples, and the outputs were compared with those of diesel fuel. As a result, the brake thermal efficiency of J10C90 was increased by 3.11% in comparison with J100. The emission such as CO, HC, and smoke were reduced by 26.02%, 28.16%, and 18.04% respectively compared with diesel fuel. From exergy analysis, the highest BTE of 28.91%, frictional loss of 6.47%, and mixing loss of 4.31% have been obtained for the J10C90 sample fuel. Finally, J10C90 is considered an optimum blended binary fuel for the upcoming future without the need for any substantial engine modifications. • Low-viscosity Cinnamon oil was a new viable additive fuel to mix with biodiesel. • Cinnamon oil and Jatropha biodiesel were synthesized and used for all tests. • Blend of 90% Cinnamon oil/10% Jatropha biodiesel (J10C90) was the best fuel sample. • Higher BTE and much lower CO/HC/smoke than diesel fuel can be obtained for J10C90. • Combustion and exergy analysis for J10C90 is better than other fuel samples. [ABSTRACT FROM AUTHOR]

• Diesel engine was powered with ternary blends of biodiesel-diesel-oxyhydrogen. • Third-generation biodiesel was synthesized from biomass of Azolla Pinnata. • A low-cost device-31 plates generator generated oxyhydrogen gas. • Oxyhydrogen addition improved engine performance and lowered emissions. • Box-Behnken design coupled with desirability approach used for optimization. The current study explores and improves the effects of engine load, injection time, and oxyhydrogen fuel flow rate on the combustion and emissions characteristics of a diesel engine. Experiment with the combustion and exhaust characteristics of a medium-sized diesel engine working in tri-fuel mode using microalgae oil methyl ester-diesel blends as injected fuel and an oxyhydrogen gas combination as inducted fuel. The Box-Behnken design (BBD) was used to reduce the number of testing. The parameters and proposed attributes were calculated utilizing response surface techniques and BBD-generated quadratic models. The response surface analysis displayed the patterns of input interactions on the output using surface diagrams. The desirability-based optimization revealed the optimal engine operating parameters as 22.92° crank angles advance, 76% engine load, and 0.92 L per minute oxyhydrogen flow rate. At these optimized operating ranges, the performance and combustion output of the study was 30.8 % brake thermal efficiency (BTE), 0.3 kg/kWh brake specific fuel consumption (BSFC), and 65.6 bar peak cylinder pressure (PCP). On the emission front, the CO emission was 0.0107%, UHC was 26 ppm, and NO x was 853 ppm. The optimized values were validated through experimental testing, and all the results were within 7% of the model-predicted output. The addition of oxyhydrogen significantly improved the combustion of an algal biodiesel-diesel-oxyhydrogen-powered diesel engine in terms of fuel efficiency and fuel consumption and lower carbon-based emission levels except for nitrogen oxide emissions. [ABSTRACT FROM AUTHOR]