CapsNet-FR: Capsule Networks for Improved Recognition of Facial Features

Face recognition (FR) technology has numerous applications in artificial intelligence including biometrics, security,authentication, law enforcement, and surveillance. Deep learning (DL) models, notably convolutional neuralnetworks (CNNs), have shown promising results in the field of FR. However CNNs are easily fooled since theydo not encode position and orientation correlations between features. Hinton et al. envisioned Capsule Networksas a more robust design capable of retaining pose information and spatial correlations to recognize objects morelike the brain does. Lower-level capsules hold 8-dimensional vectors of attributes like position, hue, texture, andso on, which are routed to higher-level capsules via a new routing by agreement algorithm. This provides capsulenetworks with viewpoint invariance, which has previously evaded CNNs. This research presents a FR model basedon capsule networks that was tested using the LFW dataset, COMSATS face dataset, and own acquired photos usingcameras measuring 128 × 128 pixels, 40 × 40 pixels, and 30 × 30 pixels. The trained model outperforms state-ofthe-art algorithms, achieving 95.82% test accuracy and performing well on unseen faces that have been blurred orrotated. Additionally, the suggested model outperformed the recently released approaches on the COMSATS facedataset, achieving a high accuracy of 92.47%. Based on the results of this research as well as previous results, capsulenetworks perform better than deeper CNNs on unobserved altered data because of their special equivarianceproperties.

Experimental Investigation of a Phase-ChangeMaterial’s Stabilizing Role in a Pilot of Smart Salt-Gradient Solar Ponds

Faced with the world’s environmental and energy-related challenges,researchers are turning to innovative,sustainable and intelligent solutions to produce,store,and distribute energy.This work explores the trend of using a smart sensor to monitor the stability and efficiency of a salt-gradient solar pond.Several studies have been conducted to improve the thermal efficiency of salt-gradient solar ponds by introducing other materials.This study investigates the thermal and salinity behaviors of a pilot of smart salt-gradient solar ponds with(SGSP)and without(SGSPP)paraffin wax(PW)as a phase-change material(PCM).Temperature and salinity were measured experimentally using a smart sensor,with the measurements being used to investigate the stabilizing effects of placing the PCM in the solar pond’s lower convective zone.The experimental results show that the pond with the PCM(SGSPP)achieved greater thermal and salinity stability,with there being a lesser temperature and salinity gradient between the different layers when compared to a solar pond without thePCM(SGSP).The use of the PCM,therefore,helped control the maximum and minimum temperature of the pond’s storage zone.The UCZ has been found to operate approximately 4 degrees above the average ambient temperature of the day in the SGSPP and 7 degrees in SGSP.Moreover,an unstable situation is generated after 5 days from starting the operation and at 1.9 m from the bottom,and certain points have the tendency to be neutral from the upper depths in 1,3 m of the bottom.

Influence of Nitric Acid Concentration on Characteristics of Olive Stone Based Activated Carbon

In this work we investigated the effect of nitric acid concentration on the pore structure,surface chemistry and liquid phase adsorption of olive stone based activated carbon prepared by mixing process using phosphoric acid and steam as activating agents.Chemicals and textural characterization show that the increase of HNO3concentration increases considerably the total acidic groups but decreases specific surface area and pore volume.The study of adsorption in aqueous solutions of two organics,phenol and methylene blue,on raw and oxidized activated carbon indicates that the treatment of mixed activated carbon with different concentrations of nitric acid improves the adsorbent capacity for methylene blue at HNO3concentrations less or equal to 2 mol·L 1,while it has a negative effect on phenol adsorption.

Adsorption of dyes onto activated carbon prepared from olive stones

Activated carbon was produced from olive stones（OSAC） by a physical process in two steps. The adsorption character of this activated carbon was tested on three colour dyes molecules in aqueous solution： Methylene blue（MB）, Rhodamine B（RB） and Congo Red（CR）. The adsorption equilibrium was studied through isotherms construction at 30℃, which were well described by Langmuir model. The adsorption capacity on the OSAC was estimated to be 303 mg/g, 217 mg/g and 167 mg/g respectively for MB, RB and CR. This activated carbon has a similar adsorption properties to that of commercial ones and show the same adsorption performances. The adsorption kinetics of the MB molecule in aqueous solution at different initial concentrations by OSAC was also studied. Kinetic experiments were well fitted by a simple intra-particle diffusion model. The measured kinetics constant was influenced by the initial concentration and we found the following correlation： Kid = 1.55 C0^0.51.

Hydrogeological Study of the Aquifer System in Central Tunisia: New System Structuring of Horchane Aquifers

Hydrogeological investigations, tectonics and seismic reflection show the complexity of the Horchane groundwater and drainage possibilities with neighboring groundwater in central Tunisia. Seismic reflection lines intersecting the region show the role of halokinetic movements, by the intrusion along preexisting faults, in the restructuring of the hydrogeological basin. The salt domes associated with a chaotic facies at the base of outcrops, that limit the Horchane basin, puch to outcrops the areas of recharge area. Geoelectric section shows the anisotropy and the importance of Mio-Plio-Quaternary (MPQ) sediment along the gutters, between the outcrops of El Hafay and Kebar on the one hand, and outcrops of Kebar and Majoura on the other. These gutters are communicated with channels that facilitate drainage of the Horchane complex groundwater by that Gammouda in North-East and Braga in East. The results of this study clearly indicate the important role of the geology in the restructuring of groundwater basins, through early halokinetic movements. (i.e. halokinetic movements). The aquifer geometry is controlled by the ascent of Triassic salt material, from the Middle Jurassic, in central Tunisia.

CFD Prediction of the Turbulent Flow Generated in Stirred Square Tank by a Rushton Turbine

The Computational Fluid Dynamics (CFD) have been used in the analysis and design of agitated vessel. Most of the researches done in this area are limited to the baffled or unbaffled stirred tank. In this paper, we have been interested in studying of the new design. Particularly, the flow and turbulence fields in square vessel stirred by a standard Rushton turbine have been simulated by means of CFD techniques. The Navier-Stokes equations governing the phenomenon of transfer of momentum are solved by a discretization method for finite volume. The MRF approaches can be used in simulation of the steady state problem. The numerical results from the application of CFD code Fluent with the stationary approach Multi Reference Frame (MRF) are presented in the planes containing the blade. The validation of CFD results with experimental measurements showed a good agreement.

Vertical Accuracy Assessment of SRTM Ver 4.1 and ASTER GDEM Ver 2 Using GPS Measurements in Central West of Tunisia

This paper focuses on the quality of the vertical accuracy of two Digital Elevation Models, corresponding to Kasserine region, central west Tunisia. The vertical accuracy assessment is based on 23 GPS ground control points belonging to the study area. We applied a statistic analysis approach and established 3 elevation profiles corresponding to GPS, ASTER and SRTM. The erected statistical analysis reveals that the Root Mean Squared Error (RMSE) was 8.88 and 10.13 respectively for SRTM and ASTER DTMs. 2D elevation profiles constructed for GPS measurements, ASTER and SRTM, highlight that both DTMs underestimate the true elevation and that SRTM DTM is quite closer to the GPS elevation profile. Relying on this investigation, we think that both DTMs are significant for the vertical accuracy assessment and we urge that SRTM DTM might scheme the Kasserine area features better than ASTER DTM.

Damping Analysis and Failure Mechanism of 3D Printed Bio-Based Sandwich with Auxetic Core under Bending Fatigue Loading

Meta-sandwich composites with three-dimensional(3D)printed architecture structure are characterized by their high ability to absorb energy.In this paper,static and fatigue 3-point bending tests are implemented on a 3D printed sandwich composites with a re-entrant honeycomb core.The skins,core and whole sandwich are manufactured using the same bio-based material which is polylactic acid with flax fiber reinforcement.Experimental tests are performed in order to evaluate the durability and the ability of this material to dissipate energy.First,static tests are conducted to study the bending behaviour of the sandwich beams,as well as to determine the failure parameters and the characteristic used in fatigue tests.Then,fatigue analyses were carried out to determine the fatigue resistance of these structures.The effects of the core density on the stiffness,hysteresis loop,energy absorption and loss factor,for two loading level,are determined.Moreover,the behaviour of this sandwich composite with re-entrant honeycomb core is compared with that of sandwiches with different core topologies.The results show that sandwich with high core density dissipate more energy,which results higher loss factors.The determined properties offer the most sensitive indicators of sandwich composite damage during its lifetime.This work aims to determine the static and fatigue properties of this material,thus,study its potential applications in industry.

Effect of Insecticides on <i>Trichogramma</i>Parasitoids Used in Biological Control against <i>Prays oleae</i>Insect Pest

This study investigated the direct effect of the insecticides deltamethrin and spinosad on three egg parasitoids species: Trichogramma oleae, T. cacoeciae and T. bourarachae. The parasitoid pupae were exposed to pesticide residues on fresh olive tree leaves at recommended concentrations (RC) at different time intervals: 3, 10, 17, 24 and 31 days after pesticide applications. Parasitism viability (% emergence from parasitized eggs) and adult emergence time (developmental time from pupa to adult emergence) were evaluated. Regarding to the International Organization of Biological Control (IOBC) guidelines, results of toxicity effects of insecticides show that: Deltamethrin was moderately harmful to all Trichogramma species at RC (Decis&reg;100 milliliters·ha&minus;1), however, spinosad was harmless to moderately harmful at RC (Tracer&reg;20 milliliters·ha&minus;1). Trichogramma species revealed differences with regard to adult emergence time and exhibited significant changes in parasitism viability with increasing time after pesticide treatment. While deltamethrin residues affected parasitism viability 31 days after the product application, spinosad displayed similar viability for almost species 24 days after the application. The usefulness of Trichogramma parasitoids used as biological control agents, in olive tree ecosystem, was discussed in integrated pest management programs for Prays oleae control when parasitoid species were exposed during pupal stage to the insecticide residue.

The Effect of the Process on Mechanical Properties of Polylactic Acid-Date Palm Leaf Fibers Composite Films Produced By Extrusion Blowing

Biocomposite films prepared with melt compounding and film blowing have become a new trend in plastic research to deliver more eco-friendly packages.Polylactic acid(PLA)was melt compounded with minimally processed date palm leaf fiber(DPLF)and converted into films by blown film extrusion.The compounding was done in order to enhance the film mechanical properties in one hand,and to decrease the film production cost in the other hand.In this present study,a reference PLA film and films with 1%,2%,and 5%of DPLF(weight%)were produced with different process parameters.The spatial variations in films thickness and lay flat width indicate that the addition of DPLF up to 2%enhances the bubble stability for the tested process parameters.However,the composite with 5%DPLF shows nearly the same processability window as the neat PLA.The structural and mechanical characterizations of films suggest a reinforcing effect of the PLA matrix up to 2%of fiber(with an optimum at 1%).Larger DPLF loading leads to depressed and more anisotropic mechanical properties,related to an increased density of defects at the fiber-PLA fragile interface and to a DPLF-induced enhanced PLA thermal degradation and amorphous phase orientation.

Crosscumulants Based Approaches for the Structure Identification of Volterra Models

In this paper, we address the problem of structure identification of Volterra models. It consists in estimating the model order and the memory length of each kernel. Two methods based on input-output crosscumulants are developed. The first one uses zero mean independent and identically distributed Caussian input, and the second one concerns a symmetric input sequence. Simulations are performed on six models having different orders and kernel memory lengths to demonstrate the advantages of the proposed methods.

Anisotropic Visco-Elastoplastic Modeling of Quasi-Unidirectional Flax Fiber Reinforced Epoxy Behavior:An Investigation on Low-Velocity Impact Response

Based on experimental test results,flax fiber reinforced polymer composites are characterized by nonlinear visco-elastoplastic behavior.The aim of this work is to model the quasi-unidirectional flax fiber reinforced composite behavior through a three dimensional formulation with orthotropic elasticity and orthotropic plasticity using Hill criterion.The isotropic hardening and Johnson Cook parameters are identified from unidirectional tensile tests at different strain rates.The adjustment of Hill’s yield criterion is developed based on yield stresses obtained in tensile tests at different directions.The numerical integration of the constitutive equations is implemented in a user-defined material,UMAT subroutines for the commercial finite element code ABAQUS.Once model parameters are identified using tensile tests,the model needs to be validated by confronting it with other experimental results.That is why experimental and numerical three-point bending tests are carried out in order to validate the proposed model with tests that have not served for the identification.Finally,a numerical parametric study on low velocity impact of a flax/epoxy composite circular plate is investigated.

Automatic Detection of COVID-19 Using a Stacked Denoising Convolutional Autoencoder

The exponential increase in new coronavirus disease 2019(COVID-19)cases and deaths has made COVID-19 the leading cause of death in many countries.Thus,in this study,we propose an efficient technique for the automatic detection of COVID-19 and pneumonia based on X-ray images.A stacked denoising convolutional autoencoder(SDCA)model was proposed to classify X-ray images into three classes:normal,pneumonia,and COVID-19.The SDCA model was used to obtain a good representation of the input data and extract the relevant features from noisy images.The proposed model’s architecture mainly composed of eight autoencoders,which were fed to two dense layers and SoftMax classifiers.The proposed model was evaluated with 6356 images from the datasets from different sources.The experiments and evaluation of the proposed model were applied to an 80/20 training/validation split and for five cross-validation data splitting,respectively.The metrics used for the SDCA model were the classification accuracy,precision,sensitivity,and specificity for both schemes.Our results demonstrated the superiority of the proposed model in classifying X-ray images with high accuracy of 96.8%.Therefore,this model can help physicians accelerate COVID-19 diagnosis.

Thermal and Structural Study of Mono- and Multi-Layered Thin Films Composed of CuAlS_(2) Chalcogenide

Thin films constituted of CuAlS_(2) nanoparticles deposited with various deposition velocities in single and multilayers onto silicon Si(111)substrates by thermal evaporation have been studied by lifting their structural and thermal properties.Thermal properties of Si(111)and Si(111)/CuAlS_(2) structures are determined by using the photothermal deflection technique by comparing experimental and theoretical signals.We succeed in extracting the thermal conductivity,the thermal diffusivity,and the electron free mean path of these deposited chalcogenide layers.For the multilayers,the obtained values of the thermal conductivity are in good agreement with the theoretical data.

Experimentation of a Plane Solar Integrated Collector Storage Water Heater

In order to popularize the use of the solar-water heaters, especially in the residential and tertiary sectors with the third world, it appears to be necessary to reduce their cost while improving their performances. It is the object of this integrated storage collector thus created and tested in the south of Tunisia. It is simply made up of a tank playing the double part of solar absorber and storage tank of warm water, of a glazing to profit from the greenhouse effect and of an insulating case. Its measured energy performances, by the method of input-output proves its effectiveness to produce hot water, in spite of its simplicity of manufacture, usage and maintenance. Indeed a temperature of water exceeding 70?C is reached towards the afternoon True Solar Time, and for an efficiency of 7%. Thus, this type of collector with integrated storage is entirely satisfactory and could be available to larger mass.

Design Analysis of DC-DC Converters Connected to a Photovoltaic Generator and Controlled by MPPT for Optimal Energy Transfer throughout a Clear Day

The DC-DC converters are widely used in photovoltaic generating systems as an interface between PV module and the load. These converters must be chosen to be able to match the maximum power point (MPP) of PV module when climatic conditions change with different resistive load values. So DC-DC converters must be used with MPPT controller in order to reduce losses in the global PV system. This article focuses on the effect of climatic conditions on design of two components (inductance, capacitance) for three topologies of DC-DC converters commonly used in PV systems. When climatic conditions change, the boundary of inductance and capacitance parameters of DC-DC converter will change. These two parameters must be properly sized to achieve optimal efficiency for each converter. The design optimization is based on two principles: 1) for a steady-state operation in a continuous conduction mode, the inductance value for all choppers must be greater than the maximum value of boundary inductance, and 2) in order to limit the output voltage ripple of DC-DC converter below a desired value, the filter capacitance must be larger than the maximum value of boundary capacitance.

Static and Dynamic Study of a Wind Turbine Blade with Horizontal Axis

In this work the authors present a calculation process of the blades for wind turbine with horizontal axis. It is about a blade discretized by the finite element method （FEM） in order to determine the gyroscopic effect during its rotation at a high speed. A blade must have the maximum output and resist to aerodynamic loads distributed over its length, which are related to its geometrical characteristics and the speed of the wind. For that, the authors wrote the relations whom determine these loads according to the flow speed of the wind, then, the authors integrated them in the laws of structure mechanics to obtain the motion equations of the blade. This process was applied to a twisted blade with a length of 1.9 m, built out of pressed aluminum sheet with a profile of the type NACA; this profile gives the best aerodynamic output. This blade is an element of a three-bladed propeller for wind turbine of maximum power 5 kW. Finally, we visualized its deformations and then the authors checked its holding in service.

Static Simulation of a 12/8 Switched Reluctance Machine (Application: Starter-Generator)

Because its high efficiency, its simple stator and rotor structures, the low cost and high reliability, speed operation combined with robust and low cost construction, the switched reluctance machines have represented. In recent years, an interesting alternative to other machine types has been chosen for traction applications especially starter-generator. Their rotors do not generate significant heat, resulting in easy cooling. Their unidirectional flux and current may generate lower core losses and require a simple converter design. Moreover, the switched reluctance machines are known for their high reliability and capability of operating in four quadrants for a variable speed drive. Despite those merits, switched reluctance machine has not been extensively used until recently because of its problems of torque ripples and noise. Additionally, researchers have faced many difficulties to build a SRM model because it is inherently multivariable. It has strong coupling and especially a high nonlinearity. In this paper, we deal with many modeling methods. Numerical, analytical and intelligent approaches are studied. The important aim in this research is to use static results from FEMM simulation as flux-linkage, co-energy, static torque to form a dynamic model of a switched reluctance machine used next as a starter-generator of a hybrid vehicle.

Hydrogen Production by Water Electrolysis Effects of the Electrodes Materials Nature on the Solar Water Electrolysis Performances

Our contribution in the production of hydrogen, vector of energy, consists in testing the water electrolysis by photovoltaic solar energy. The realization of some electrolysers whose electrodes are various materials, showed a clear difference from the point of view produced hydrogen flow, conversion efficiency, energy specific consumption and the electrodes lifespan. This made it possible to classify materials, by performances descending order, as follows: copper, lead, bronzes, aluminum, stainless, graphite and steel. However lead has a too low flow and aluminum corrodes quickly. Steel admits poor yield and lifespan. Then, we retain primarily copper like anode metal. To increase the hydrogen produced flow by electrolysis, the electrolysers parallel assembly choice is essential. According to the hour of the day, the evolution of the parameters such as consumed current, efficiency, and specific energy differs from a material with another, which can be explained by the variation of solar energy during the day.