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In this work, we investigated the structure, mechanical properties and corrosion resistance of Ti50Ni50 and Ti16.667Zr16.667A16.667Ni25Cu25 (A = Hf, Nb, Co, Cr and Ga) shape memory alloys (SMAs) fabricated by using melt-spinning method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses reveal that the alloy ribbons are partially crystallized with B19' martensitic structure in the added alloys. The crystalline phase formation and the atomic size difference (δ = 4.33 - 10.25%) significantly affect the hardness, tensile strength, tensile strain, elastic modulus and corrosion resistance of the alloys. The hardness of the alloy gradually increases from 583 HV to 873 HV when adding elements in the order of Hf, Nb, Co, Cr and Ga. Tensile strength, tensile strain and elastic modulus simultaneously reach their maximum of 669.2 MPa, 0.899% and 28.82 GPa, respectively, when Hf is added to the alloy. Ga enhances the corrosion resistance of the alloy ribbons more than other additional elements.

This paper proposes an effective network reconfiguration (NR) method in the presence of distributed generations (DGs) for energy loss. The proposed method uses average load and average power of DGs instead of the load and DGs’ generation curves. For finding the optimal network configuration, pathfinder algorithm (PFA) is used to solve the NR problem. The effectiveness of the proposed method has been validated on two distribution network systems without and with DGs placement. The obtained results show that the proposed method has a good ability to determine the optimal configuration similar to the method based on the graphs of loads and DGs with much shorter calculated time and PFA can reach optimal solution with a much higher success rate and better obtained solution compared with particle swarm optimization and sunflower optimization algorithms. As a result, the proposed method is an effective and reliable method for solving the NR problem for energy loss reduction considering time-varying condition of loads and DGs.

The paper proposes a new speed control method to improve control quality and expand the Permanent Magnet Synchronous Motors speed range. The Permanent Magnet Synchronous Motors (PMSM) speed range enlarging is based on the newly proposed power control principle between two voltage sources instead of winding current control as the conventional Field Oriented Control method. The power management between the inverter and PMSM motor allows the Flux-Weakening obstacle to be overcome entirely, leading to a significant extension of the motor speed to a constant power range. Based on motor power control, a new control method is proposed and allows for efficiently reducing current and torque ripple caused by the imbalance between the power supply of the inverter and the power required through the desired stator current. The proposed method permits for not only an enhanced PMSM speed range, but also a robust stability in PMSM speed control. The simulation results have demonstrated the efficiency and stability of the proposed control method.

Partial shading is the cause of the reduction of the output power of the photovoltaic (PV) system due to changes in its P-V characteristic curve. Global Maximum Power Point Tracking (GMPPT) in more complex and multiple peaks conditions is the biggest challenge for current MPPT techniques to improve the performance of the system. This article introduces an improved method based on the traditional Particle Swarm optimization (I-PSO) algorithm to increase the convergence speed in a constantly changing and complex environment. The study not only considers the influence of the best location of the individual and the swarm but also focuses on the experience of the neighboring individuals with a better position to avoid the local extreme trap. In addition to that, a boost converter uses to simulate the proposed algorithm applying PSIM software. The simulating results with those previously under the same operating conditions showed the superiority of the proposed approach in improving the efficiency of the photovoltaic system.

A new combination between a three-phase threelevel quasi-Z-source inverter and redundant unit form which ensured the operation of the T-type inverter in open-circuit fault is introduced in this paper. By consisting of the quasi-Z source network, this topology has some advantages such as: behaving as a buck-boost converter and shoot-through immunity. Furthermore, the redundant unit added into traditional T-type inverter helps to solve the open-circuit fault occurring in semiconductor devices of the converter without degrading the peak-value of the load current or increasing the DC-link voltage like traditional open-circuit fault-tolerant scheme. The PWM technique and the operating principle are detailed in this paper. The effectiveness of the inverter is verified through simulation results by using MATLAB Simulink.

This paper proposes the non-isolated DC-DC converter with high boost ratios and efficiency. We suggest boosting methods including voltage multiplier cells or coupled inductors. However, both techniques have a limited constant voltage multiplier coefficient according to the fixed configuration. Therefore, in the proposed method, we change the multiplier factor (as the number of activity levels) and combine it with the turn of the appropriate duty cycle, these factors are considered at the same time in order to increase the energy conversion efficiency and expand the control area of the duty cycle. A mathematical analysis of the losses of the components in operation modes shows that the boost ratio and efficiency are functions of the number of activity levels and duty cycle. Therefore, this paper proposes an algorithm for tracking the activity levels and duty cycle in order to obtain the maximum efficiency. The simulations produced with the Powersim-PSIM software, and the experiments with load capacities of 250 W, 500 W and 1000 W, boosting the ratio by more than ten times, were conducted in order to clarify the capabilities of the proposed configuration.

The controllers of three-phase grid-connected inverters usually require improvements to meet the stringent grid codes with the fault-ride-through (FRT) capability. Therefore, the performance of the grid-connected inverter depends on the quality of the selected phase-locked loop (PLL). This paper proposes a PLL method that has greater accuracy and better dynamics under an unbalanced and highly distorted voltage. The proposed method is based on the least squares technique using the Levenberg-Marquardt algorithm with adaptive initial parameters for rapid convergence to the solution. The simulated and experimental results under unbalanced and harmonic voltage validated the performance of the proposed method.

Regular monitoring of glucose concentration is essential and urgency, especially diabetics. However, those methods which involve finger puncturing are invasive, expensive as well as painful. Also, there are risks of infectious diseases using these techniques due to the contact of the needle on human skin. This paper proposed a non-invasive glucose monitoring system utilizing the near-infrared (NIR) light to measure the glucose concentration in the human blood. The designed system uses a 980 nm-wavelength NIR LED transmitting through d-glucose phantom samples, a photo-sensor for analyzing the transmitting optical parameters, a filter & an amplifier circuit, and a Nano Arduino microcontroller. For calculating the values of glucose concentration, the R programming with the methodology of the artificial neural network (ANN) was applied. This type of methodology is considered as one of the most useful technique in the world of data analysis and because it is adaptive, learns from the provided information and optimizes for better prediction outcomes. The ANN is used to predict the correlation equation between collected voltage and glucose concentration. The obtained glucose level is demonstrated directly on the system’s screen or further sent to the user’s mobile phone. The result obtained shows a correlation between the transmittance and the concentration of d-glucose solution. The correlation parameter of the technique is R2 = 0.9957. Despite having the acceptable results, there are still some improvements that could be carried out for more accurate measurement (angle of the LED, a procedure of filtering and amplifying, usage of an optical instrument…). For further investigation and development, it is predicted that the result can be more accurate, precise and sensitivity as much as possible.

In recent years, the quasi -switched boost inverter uses widely in electrical systems. This paper proposes a method to control the AC output voltage and reduce the current ripple of the booster inductor in the quasi-switched boost inverter (QSBI). The proposed technique base on carrier pulse width modulation with two triangles with phase shifts 90◦. This technique uses the offset function to expand the modulation index and the algorithm for output voltage stabilization based on the adjustment of the boost ratio. The modulation index expansion will reduce the stress voltage on the switches by an average of 16.5% under the simulated conditions. The boost factor base on the short circuit time on the DC / DC booster and the inverter on the zero vectors. So, the duty ratio (of the boost DC / DC) can reduce by the short-circuit pulses that insert in the position of zero vectors, so the inverter is responsible for both boosting and inverting. The combination helps to reduce the current ripple on the boost inductor. Besides that, reducing the short-circuit ratio of DC / DC booster will also reduce the capacity of the booster switch and thereby reduce the production cost. The analysis clarifies the proposed technique. Simulations and experiments evaluate the proposed method.

Photovoltaic is used to convert electricity from solar radiation. The working characteristics of photovoltaic depend on environmental conditions such as temperature, solar radiation intensity, and the surrounding environment. During operation, the photovoltaic generation system (PGS) can be partially or completely shaded due to natural phenomena such as clouds, buildings, dust, animals, electric pillars, trees ... these are changing the characteristics of the system’s power output of PV. This paper proposes a maximum power point tracking algorithm for PGS operating under partially shaded condition (PSC) based on Particle Swarm Optimization (PSO) method, and a configuration comprises of three PV modules type PHM60W36 is used to simulate using PSIM software. The study focused on changing the working characteristics of the photovoltaic system when changing factors such as level, location of the photovoltaic module are shaded. The effectiveness of the proposed method is not only compared with the traditional Perturb and Observe (P&O) method but also compared with those proposed previously under the same operating conditions. In addition, an experimental model was developed to investigate the response of the proposed solution in the real environment with the Chroma-62050H simulator. The results show the superiority of the proposed solution in improving the performance MPPT and convergence speed of the system under complex operating conditions.

The thermal conductivity (TC) of polymer composites with randomly distributed hybrid fillers is investigated numerically and theoretically. The effective thermal conductivity (ETC) of such composites is examined under various effects, such as the TC ratios, volume fraction (VF), and particle distribution, particle size, and particularly thermal contact resistance (TCR). The contribution of particle distribution to the ETC were explained comprehensively, which is as a function of projected area and effective length of hybrid fillers. Results indicated that the optimal ETC was affected significantly by particle distribution and particle size at high VF, high TC, low TCR, and largely total particle size of hybrid fillers. However, particle distribution and particle size show not to affect considerably to the value of the optimal TC ratio between two fillers. Particularly, it was confirmed that the TC is generally enhanced when more particles are stacked and concentrated along the thermal flow direction regardless of the effects of TCR. In addition, modified Hashin-Shtrikman model by Ngo's study again shows a good TC prediction even with the TCR effect. These results are very good in practical optimization process to achieve the maximum ETC of composites, thus total cost of composite synthesis can be reduced significantly.

Cavitation in a 3D axisymmetric rectangular groove occurred in various types of cavitation, such as vortex cavitation, cloud cavitation, traveling cavitation and sheet cavitation. In this experimental study, some aspects of cavitating flow were clarified. Prediction and experimental calculations were also made for incipient cavitation of both the cavitating vortex ring in the groove and the sheet cavitation at the downstream of the groove. The calculations indicate that the observed cavitation is not vaporous cavitation, but gaseous cavitation. The results of this study are useful for understanding the cavitation in this type of groove structure in order to control cavitation damage.

International audience; The goal of the paper is to perform a cooperation between multiple Unmanned Aerial Vehicles via a mission planner. This mission planner is a generic one which could be used not only for UAV domain but also for other human-machine systems such as maritime, automotive and manned aerial vehicle (MAV). It is a completed mission planner including the high level task planning and low level of collision avoidance. Our first scenario shows the cooperation between UAVs during doing tasks when the number of UAVs is greater than that of tasks. The later scenarios will be the cooperation between two types of UAV: fixed-wing aircraft and rotor-craft for different types of task. This mission planner contributes a new module to both simulation platform and real demonstrator of relevant projects.

Ultrasonic horn transducers – also called sonotrodes or disintegrators – are frequently used in applications of acoustic cavitation in liquids, for instance for cell disruption or sonochemical reactions. They are operated typically in the frequency range up to about 50 kHz and have tip diameters from some mm to several cm. If the horn tip is sufficiently small and driven at high amplitude, cavitation is very strong, and the tip can be covered entirely by the gas/vapour phase for longer time intervals, which actually interrupts the horn-liquid contact. From acoustic emission spectra and high-speed photographic recordings, a peculiar dynamics of this attached cavitation sheet in front of the tip can be observed. In particular, expansion and collapse can be subharmonic with respect to the driving frequency. The gas/vapour phase can appear in a mushroom shape and split or eject a larger cluster which violently collapses below the tip. Here, we show some experimental observations of the cavitation zone below a tip of 3 mm diameter, driven at 20 kHz. For modeling purposes, a hydrodynamic cavitation code is employed.

The trajectories of walking humans can be divided into two major classes: first, nonholonomic trajectories during which the orientation of the human body and the one of the motion are aligned (e.g., straight walking), and second, holonomic ones during which lateral velocities are observed (e.g., side-steps). The major contribution of this work is a general locomotion synthesis method for digital actors which enables combining nonholonomic and holonomic walk behaviors. Our motion synthesis technique is based on a motion capture blending method. Such a method is able to transform a low-dimensional trajectory describing the global displacement of a digital actor into a high-dimensional motion which involves all the degrees of freedom of the digital actor body. We extend previously existing motion blending techniques [12] to reach this goal. More precisely, we consider lateral velocity as a new input of the motion synthesis problem, whereas only tangential and angular were initially considered. Thus, the digital actor locomotion is controlled from 3 inputs in our approach: the tangential velocity, the angular velocity and the lateral velocity. The paper describes the major steps of our approach. At pre-processing, we analyze some motion captured locomotion cycles to build a Motion Library. The content of the library is projected into the Control Space. Then, at runtime, input (i.e., desired walk velocities) is also projected into the Control Space. We deduce a selection of motion captured locomotion cycles from the library, which are finally interpolated to generate a locomotion animation for digital actors. The newly generated locomotion cycle exhibit the desired input velocities.