In this paper, numerous experimental tests were carried out to study the behavior of concrete containing glass fibers and confined with glass fiber-reinforced polymer (GFRP). Concrete specimens containing different fiber percentages ( 0.3 wt.%, 0.6 wt.%, 0.9 wt.% or 1.2 wt.%) and with different strengths of concrete (8.5 MPa, 16 MPa and 25 MPa) and different confinement levels (two, four and six layers of GFRP) were used as research parameters. The samples were tested to failure under pure axial compression. The results imply that the confinement effect with GFRP is relatively higher for concrete samples containing glass fiber (GFCC) with a percentage equal to 0.6 wt.%. The theoretical of stress ratios (fcc/fco) estimated by using existing ultimate strength models are found to be close to the experimental results for high strength of GFCC, but not close to the experimental results for low strength of GFCC.
The solar chimney power plant (SCPP) has been studied in many works but most have focused on outside urban areas, due to dimension constraint. This paper aims to offer a database for an appropriate integration of SCPP in urban areas. For this purpose, a 3D axisymmetric CFD model was established for the SCPP in Manzanares, Spain. Six chimney models were successively reduced by a 0.5 scaling factor and exposed to different solar radiation, thereby generating 30 scenarios. The RNG k-ε turbulence model and discrete ordinates non-grey radiation model were adopted. The paper contains also an applied example of using results in evaluating daily energy production from proposed chimneys on industrial buildings roofs. The results showed that air velocity, pressure difference, and mass flow rate follow puissance, linear, and polynomial decrease, respectively, as the scale factor reduces, whereas the temperature logarithmically rises. Moreover, output energy and system efficiency follow puissance and polynomial decrease, respectively, as the scale factor reduces. Exposure of the system to radiation 1000 w/m 2 generate 21.2, 11.74, and 5.65 kW/h electrical power for scale factors 0.76, 0.636, and 0.51, respectively. Where they provide a daily energy 191.93, 106.55 and 51.12 kwh/day on a day type in Batna, Algeria.
In this study, a new approach integrating a groundwater vulnerability method and a numerical model for predicting groundwater resource sustainability under actual and future conditions of exploitation (2010–2030) is proposed in the semi-arid region of the Tebessa-Morsott alluvial aquifer (northeastern Algeria). The groundwater vulnerability method-based DRASTIC model was used to evaluate and delineate the vulnerable areas using a GIS technique. The MODFLOW code, on the other hand, was used to calculate the dynamics of groundwater level under actual and future conditions of exploitation considering two scenarios. The results of the application of the DRASTIC method to the reference year conditions (year 2010) showed that the high and average vulnerability classes covered a wide zone of the study area, about 97%. These results were validated based on the nitrate concentration values (R2 = 0.955). However, the results for predicting future groundwater vulnerability showed that groundwater vulnerability variation over time (period 2010–2030) was closely related to groundwater depth variation caused by the pumping rate, since the decreases in the piezometric level produce a worsening of groundwater vulnerability. To achieve better groundwater management, an experimental site for artificial recharge supplemented by hydro-chemical monitoring of the groundwater could be an effective remediation strategy.
In the current work, we deal with a class of stochastic time-fractional integral equations in Hilbert space by studying their well-posedness and regularity. Precisely, we use the celebrity fixed point theorem to prove the well-posedness of the problem by imposing the global Lipschitz and the linear growth conditions. Further, we prove the spatial and temporal regularity by imposing only a regularity condition on the initial value. An important example is considered in order to confirm and support the validity of our theoretical results. ARTICLE HISTORY
Solar energy is one of the longest-standing renewable in the world. It is available at no charge and could easily be exploited to reduce dependence on hydrocarbon-based energy. Solar radiation data plays an important role in the design, size, and efficiency of energy systems and renewable. However, these data are not available in all cases, particularly in isolated areas. Therefore, prediction of solar radiation values is often the only practical way to obtain such data. In fact, the measured sequences of radiation values are only available for some locations or regions in each country. Neural networks are classified among the techniques of artificial intelligence, its simulation of human reasoning characterizes it and neural networks have contributed to the development of several areas. In prediction, neural networks are used to solve complex forecasting problems. In this work, fifteen neural models are implemented for the modeling and prediction of global solar radiation over a horizontal surface using neural networks. The meteorological parameters are: duration of sunshine (S), hours of light (S 0 ), total extraterrestrial solar radiation, temperature and humidity. Batna has been selected for this study, with its ten years (1996–2005) meteorological datasets collected from the HelioClim1 (HC1) database. The obtained results show that the news neuronal models are efficient for predicting daily global solar radiation with good measurement precision in this town.
Turbulent flows are characterized by the presence of "scales of fluctuations", or "structures" of varying magnitudes, the effects in which the mixing, transfer and dissipation of energy are preponderant. Most importantly, dissipation determines the depth profile of the flow. This contribution aims to implement a model able to predict unsteady turbulent flows generated by the presence of obstacles in a channel with complex geometry and to report, where the complexity of the phenomena are observed, such as: the separation of the boundary layer, the succession of vortices, local heat transfers, and the recirculation zones in the wake of obstacles and the oscillatory regime of the hydraulic jump for which this research is of exclusive interest. The current work therefore, presents the numerical simulation in unsteady turbulent regime based on the resolution of balance equations, using the RANS (Reynolds-Averaged Navier–Stokes) approach with an RNG k−ε closure model. To solve the incompressible Navier–Stokes equations governing these flows, we appealed to the motivated finite volume method, and its ability to process complex geometries. The simulation software FLUENT we used is based on the finite volume method. It allows to explore, the velocity and pressure fields in the digital channel of the studied flows.
Sedimentation of dam reservoirs is a complex problem with several dimensions, including filling rates and characteristics of accumulated sediments. Sediment supply from river basins is particularly high in this region because of its semi-arid climate and especially because of poor vegetation protection. The amount of silt accumulated annually since the construction of this dam is estimated at 330000 m³. This silt accumulation strongly limits its storage capacity and consequently its operating duration. The consequences of this serious problem have been catastrophic, including a considerable reduction of 43–84% of the storage capacity of the dams and a clear degradation of water quality that can cause the degradation of the ecosystem functioning and can lead to irreversible changes. The silt present in abundance in the Algerian dams can, thus, constitute a potential resource to be judiciously exploited towards the increase of the performances of the construction materials. The extraction of sediments accumulated in the dam reservoir is, therefore, imperative. These sediments have a great geotechnical value. The objective of this study is to assess the feasibility of the recovery of mud by studying the knowledge of the sediments of the dam of Koudiat Medouar. The results of the tests carried out in laboratory allowed us to identify the various sediments from a physical and geotechnical point of view. These materials must of course meet certain rigorous criteria in terms of mechanical strength and durability and environmental impact. The experimental approach that we adopted allowed us to determine the characteristics of the materials necessary for the realization of compressed earth bricks (BTC) in conformity with the recommendations of the technical guides of construction.
This article investigates experimentally and theoretically the adsorption of Basic Red 46 cationic dye (BR46) using activated carbon generated from cactus fruit peels (ACCFP). The prepared adsorbent was characterized by different analytical tools showing a good surface for the uptake of pollutants. A maximum batch adsorption capacity of 806.38 mg g-1 was achieved at optimal conditions. The Freundlich model best represented the equilibrium data, although the pseudo-second-order kinetic model best described the adsorption kinetics. The thermodynamic studies demonstrated that the adsorption process was spontaneous (ΔG°<0) and endothermic (ΔH° =32.512 kJ mol-1). DFT descriptors were combined with COSMO-RS and AIM theory to provide a complete picture of the adsorbate/adsorbent system and its molecular interactions. Last, the ACCFP was regenerable up to four times, emphasizing the idea of using it as an adsorbent to treat textile wastewaters.
In this work, we interest in the study of the wellposedness and the stability of fractional stochastic nonlinear heat equation in the Hilbert space L2(0,1); perturbed by a trace-class noise and driven by the fractional Laplacian. Precisely, we use the fixed point theorem to prove the wellposedness of the problem. Moreover, we prove the pth-moment exponential stability and the almost surely exponential stability by imposing an additional assumption. Some examples are considered in order to confirm and support the validity of our theoretical results.
The potato is a staple food crop worldwide and the need for this product has increased due to the burgeoning population. However, potato production is highly constrained by biotic stress interference, such as Myzus persicae Sulzer, which causes serious yield losses and thus minimizing production income. The current study aims to investigate the effect of different formulations prepared as an invert emulsion with different concentrations of fungal culture filtrates derived from three endophytic fungi (genus Cladosporium) against Myzus persicae. All formulations have demonstrated an aphicidal activity, which increases with the increasing concentration of fungal filtrates. Furthermore, it has been noted that chitinolytic activity recorded for 12 days is important in Cladosporium sp. BEL21 isolated from dwarf mistletoe Arceuthobium oxycedri. The study of demographic and embryonic parameters of aphids settled on potato plants previously treated with formulations revealed a significant reduction in the numbers of colonizing aphids and a relative increase in the numbers of winged adults, especially in plants treated with BEL21-derived emulsion. The pre-treatment of plants may interfere with and negatively influence embryonic development and early maturity of the embryo and thus affect the fertility of parthenogenetic aphids. BEL21-derived emulsion can ensure effective and an inexpensive control of M. persicae for potato spring cropping systems. The current results open real opportunities concerning the implementation of ecofriendly and potent potato protection systems.
Solid-liquid equilibria for binary mixtures formed by biphenyl and n-tetracosane and ternary mixtures formed by n-tetracosane + dibenzofuran + biphenyl were experimentally determined using differential scanning calorimetry (DSC). The liquidus lines were established from the onset temperatures of the melting peaks observed in the thermograms. The experimental data were compared to predictions made by a thermodynamic model considering ideal solution. Non idealities were also computed by means of the group contribution method UNIFAC. Original UNIFAC and several modifications such as UNIFAC-Lyngby and UNIFAC-Dortmund versions were assessed. The polymorphism phenomenon was considered and the heat capacity contribution was supposed to be negligible since the involved compound have nearby melting points. The best description is obtained with UNIFAC-Lyngby method, which leads to the lowest deviations in melting temperature and activity coefficients. This work contributes to acquire knowledge about solid-liquid phase behavior of multi-components systems containing heavy n-alkanes and aromatics, which is scarce in literature.
The present study was designed to verify the effectiveness of the image analysis method for body measurement in dromedary camel compared to manual measurements as a reference method. To achieve this aim, twenty-one linear body measurements were estimated on 59 adult Sahraoui dromedary camels (22 males and 37 females) with a normal clinical condition by using a measuring stick or vernier caliper (standard method). On the other hand, image analysis on profile, front, or behind photographs was processed using Axiovision Software. Overall mean comparison, relative error, variance, Pearson’s correlation coefficient, and coefficient of variance showed that the image analysis method was accurate in relation to the manual measurement. Furthermore, image analysis results indicated relevant accuracy (bias correction factor, Cb ≈1) and precision (Pearson ρ ≈1) which were significantly correlated with the results of the reference method (Lin’s concordance correlation coefficients rccc ≈ 1). According to Bland–Altman upper and lower limits of agreement, the concordance was estimated between 93.22 and 98.3%. Passing-Bablok regression showed a good relationship between the results of the two methods displaying no significant systematic and proportional bias. The image analysis method for linear body measurements in dromedary camel showed results that are in agreement with the manual measuring method. Therefore, the image analysis could be considered a valid tool for camel conformation trait studies.
In this study, we present the airfoil collocation approach employing a new efficient procedure for approximating the solution of a system of two logarithmic integro-differential equations. We demonstrate the existence of solutions to the approximation equations and conduct an error analysis. It is necessary to solve two systems of linear equations. Finally, a numerical example demonstrates the method’s precision.
Fluorizoline is a cytotoxic trifluorothiazoline that targets the scaffold proteins prohibitins-1 and -2 (PHB1/2) to inhibit the kinase C-RAF and promote the expression of the cyclin-dependent kinase inhibitor p21 to induce cancer cell death. In melanocytes, fluorizoline also induces the synthesis of melanin. Herein we report the first structural requirement of fluorizoline analogues for these activities. We identified in particular some compounds that display enhanced anti-C-RAF and anti-MEK activities, and a higher cytotoxicity in HeLa cells compared to fluorizoline. These results provide a foundation for further optimization of PHB ligands for the treatment of cancers. We also discovered an analogue of fluorizoline that displays pharmacological effects opposed to those of fluorizoline and that can be used as a chemical tool to explore PHB signaling in cancers and other diseases.
Two species of plants commonly used for their mainly their therapeutic values and available in some herbalists shops, namely: Brocchia cinerea and Matricaria pubescens that both belong to asteraceae family, and encountered mainly in the Algerian desert, have drawn attention in the scope of assessing their mineral contents, in fact minerals play an important role in the plant homeostasis and metabolism, on the other hand they may influence the health conditions mainly due to toxicity, and also the benefits that the plant consumer could have, the current study aimed to assess the contents of Al, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Zn, As, Na, K, Mg, P, S and SI, beside comparing the obtained results to other similar studies, the aerial parts of the plants are collected from several sites then mineralized and analyzed using ICP-AES and AAS, high levels of Na, K and Mg have been noted, on the other hands levels of metals were noted to be overall marginal, except for Al and Hg for the sample of Brocchia cinerea from El oued, the levels of As also seemed to be high in all the samples, inversely to the levels of S and P which seemed lower than those noted for other plants in paralleled studies, while that similar results were found for Zn, Fe, the chemical and geologic features of the soils may be the influencing factor. Additionally the current study may put first milestone for the establishment of national guidelines regarding the mineral contents of medicinal plants.
The study aimed to isolate rare halophilic actinomycetes from hypersaline soils of Algerian inland Wetland Ecosystems “Sebkhas-Chotts” located in arid and hot hyper-arid lands with international importance under the Ramsar Convention and to explore their enzyme-producing and antibacterial abilities. The halophilic actinomycetes were selectively isolated using agar-rich media supplemented with 5, 10, and 15% (W/V) of total salts. Thirty-one isolates were obtained and 16SrRNA gene sequencing analysis revealed the presence of members affiliated to rare halophilic actinobacterial genera (Actinopolyspora and Nocardiopsis) accounting for 74.19% (23 isolates out of 31) and 25.8% (8 isolates), respectively. Both phylotypes are alkalitolerant and halophilic thermotolerant actinomycetes displaying significant hydrolytic activities relative to (amylase, asparaginase, cellulase, esterase, glutaminase, inulinase, protease, pectinase, xylanase), and over 96% of tested isolates exhibited all common enzymes, mainly active at 10% of growing salt. In addition, high antibacterial activity was observed against Bacillus cereus, Bacillus subtilis, Micrococcus luteus, and Staphylococcus aureus. The findings showed that saline wetlands ecosystems represent a rich reservoir for the isolation of significant rare halophilic actinomycetes with potential adaptive features and valuable sources for novel bioactive metabolites and biocatalysts of biotechnological interest.
With the high rate of accidents and crimes around the world, the importance of video surveillance is growing every day and intelligent surveillance systems are being developed to perform surveillance tasks automatically. Detecting human beings accurately in a visual surveillance system is crucial for diverse application areas. The first step in the detection process is to detect moving objects. Then, the moving object could be classified either in the human class or in the non-human class. Human classification is an important process to build effective surveillance system. In this article, an efficient human detection algorithm is proposed by processing the regions of interest (ROI) based on a foreground estimation. In our proposal, we used MobileNetV2 deep convolution neural network, designed to be used in embedded devices, with transfer learning approach to build fine-tuned model for an efficient classification of ROI into human or not human. We train the fine-tuned model on INRIA person dataset using three scenarios. The resulting models were extensively evaluated on INRIA test dataset benchmark and they achieved an F-Score value of 98.35%, 98.72%, and 98.90% which we consider very satisfactory performance. The best fine-tuned model was used for the classification stage which achieved an accuracy of 98.42%, recall of 99.47%, precision of 98.34% and F-Score of 98.90%.
Tolga groundwater is one of Biskra's most important water supplies for both drinking and agriculture. The purpose of this study is to assess the hydrochemical and isotope ( ² H and ¹⁸ O) signature of water in the Tolga area. To evaluate the hydrogeology of groundwater in the Tolga region, a chemical, piezometric, and isotopic research was employed. The results of the Piper diagram revealed that there is just one major hydrochemical facies in the research region, which corresponds to Ca–Mg–Cl–SO 4 . The piezometry of limestone sheets shows that as one goes westward, the turns become less substantial, with turns about 20 meters and a piezometric level of 140 m. For the first time, the local meteoric water line (LMWL) was drawn for Complexe Teminal (CT) and Continental Intercalaire (CI) on Tolga groundwater. The Tolga area LMWL refers to the equation δ ² H= 7,18 δ ¹⁸ O + 4.17 with R ² about 0.85. CI and CT measurement locations indicate deuterium excess values ranging from 8.35 to 12.57. Indeed, the majority of values were more than 10‰ (mean of 10.36 ± 2.01‰). Furthermore, waters from Eocene have an isotopic composition of -7.57 ± 0.68‰ in δ ¹⁸ O and − 49.04 ± 4.69‰ In δ ² H. The results of the sample characterisation analysis show that the majority of the groundwater samples analysed are of the Ca-Mg-SO 4 water type. In addition, the intense exploitation aquifer water and the region's arid climatic conditions resulted in a large decrease in the piezometric limestone level. Finely, the signature of ² H and ¹⁸ O data indicate that water comes from local precipitation and recent water, and groundwater recharge is influenced by quick infiltration.
The aim of this study was to determine the influence of social media on students’ awareness of responsible behaviour during the COVID-19 pandemic. The field study was carried out with a sample of 726 students from Northern Border University. Data were collected from electronically retrieved questionnaires via various communication channels and analysed using hierarchical linear regression. The study found a relationship between the use of social media sites and awareness among students, affected by age differences. With the emergence of the COVID-19 pandemic, universities face the challenge of ensuring precautionary guidelines to prevent the virus are followed while educating their students, and social media plays a significant role in disseminating this information. Therefore, studying how social media helps develop students’ awareness can contribute to addressing some of the problems faced by decisionmakers in Saudi universities.
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