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In recent years, the remarkable photoelectric properties exhibited by perovskite materials have stimulated scientific inquiry, prompting investigations into novel perovskite variants and derivatives characterized by environmentally friendly attributes and robust stability. These materials offer potential as efficient solar light harvesters. Our study concentrates on elucidating the structural, electronic, and optical properties of the newly discovered stable lead-free double perovskite K2AgSbBr6, employing first-principles methods rooted in Density Functional Theory (DFT). We confirm the structural and dynamical stabilities of K2AgSbBr6 through computational analysis. Our calculations reveal that the examined compound exhibits characteristics of an indirect semiconductor, with a band gap of 0.857 eV (L-X). Notably, our findings demonstrate that the compound displays enhanced photovoltaic performance, as evidenced by elevated optical absorption coefficients exceeding 105 cm−1, surpassing those of CH3NH3PbI3. These results underscore the potential of K2AgSbBr6, a novel lead-free double perovskite, as a promising candidate for exceptional light-absorbing material spanning the UV and visible spectra.

In this groundbreaking study, we unveil the remarkable structural, electronic, and optical Properties of the newly discovered double perovskite material, K2AgBiI6, presenting a paradigm shift in materials science. The unique crystal structure and diverse atomic interactions inherent in this double perovskite make it an up-and-coming candidate for various technological applications, particularly in photovoltaics; owing to its stability and resistance to heat and humidity, we aim to shed light on the extraordinary potential of K2AgBiI6. Our study provides valuable insights for researchers engaged in tailored material design. We anticipate that the exceptional electronic properties of K2AgBiI6 will not only redefine the boundaries of materials engineering but also catalyze unprecedented advances in sustainable technology. Employing the powerful computational tool CASTEP, we conducted detailed electronic structure calculations within the framework of Density Functional Theory (DFT) to unravel the electronic properties of the double perovskite K2AgBiI6. Our investigation thoroughly explored structural properties, band structure, total density of states (DOS), and partial density of states (PDOS). Furthermore, we systematically examined the influence of different exchange-correlation functionals, including LDA, GGA, and m-GGA, on the electronic and optical features of the material by presenting a comparative analysis of these approximations.

Effective disaster management heavily relies on accurate flood susceptibility mapping. The fuzzy analytic hierarchy process (FAHP) is adept at considering the imprecise nature of decision-making criteria. This study assesses FAHP's effectiveness in flood susceptibility mapping, comparing it with the conventional analytic hierarchy process (AHP). By using Geographic Information System-analyzed remotely sensed data, the research systematically evaluates flood risk southeast of Algiers. Various datasets, including Digital Elevation Model, slope, precipitation, and land use maps, were collected via remote sensing. A linear fuzzy membership function transformed the data into fuzzy values. AHP determined the importance of each dataset, with calculated weights multiplied by corresponding fuzzy values. Fuzzy analysis combined these characteristics into a five-category flood risk map, verified with Google Earth and satellite images. Results indicate a high potential for flood hazard mapping, categorizing 30% of frequently flooded regions as high risk. Maps reveal north basin areas are more flood prone due to excessive precipitation, and urban areas in floodplains are vulnerable. Receiver operating characteristic (ROC) curves and area under the ROC curve (AUC) assessments demonstrate AHP and FAHP's effectiveness. AUC values of 88.40 and 92% indicate that both models accurately predict flood-prone areas. FAHP excels, reducing subjectivity and ambiguity in human judgments. HIGHLIGHTS Fuzzy analytic hierarchy process (FAHP) excels in handling uncertain factors for accurate flood maps.; Utilizes diverse remote sensing data, converted into fuzzy values.; Comparative study in Sahel shows FAHP's superior performance (area under the receiver operating characteristic curve: 92%) in mitigating judgment uncertainty.; Maps reveal high susceptibility in heavily precipitated northern regions and floodplain urban areas.;

Hydrological modeling is a critical and decisive technique for estimating hydrological processes and the availability of water resources. In our research, we used Hydrologic Modeling System (HEC-HMS), a 4.4 version, to achieve the affected goals, and a watershed in the east of Algeria, known as Rhumel Smedou watershed, was chosen as a case study which covers an area of 1,083 km2. A Geographic Information System (GIS) was used to analyze and process the Digital Elevation Model 30-meter resolution data accompanied with Landsat of Land Use Land Cover 10-meter resolution with accuracy to extract and deduce the basic inputs of the simulation model, which are: curve number (%), lag time (mn), impermeability (%), and rainfall (Ia) (mm). The research purpose is to compute runoff depth and volume rate for four extreme events. Two events are chosen for model calibration and two for model validation. The results of the statistical tests [NSE (%) RMSE_PBIAS (%)] proved the success and ability of the model to achieve the research objectives, and their averages were as follows: [82%_0.45_32.55%] for calibration phase, and [77%_ 0.45_30.95%] for validation phase. After calibrating and validating the effectiveness of the model, the volume and flow were predicted for different return periods (2y, 10y, 50y, and 100y).

This study investigates the electronic and optical properties of calcium-doped strontium hydride (SrH2) using first-principles density functional theory (DFT) calculations via the CASTEP code with generalized gradient approximation (GGA). We explore the impact of calcium (Ca) doping on the electronic band structure, density of states (DOS), and optical absorption spectra of SrH2. Our results show that Ca doping significantly alters the electronic properties of SrH2, notably increasing the indirect bandgap from 1.3 eV to 1.6 eV. The DOS analysis reveals new states near the Fermi level, primarily from Ca 3d orbitals. Moreover, the optical absorption spectra display enhanced absorption in the visible range, suggesting the potential for optoelectronic applications. This research highlights the feasibility of tuning the electronic and optical characteristics of SrH2 through Ca doping, thus opening the way for the generation of advanced materials with tailored properties.

The current research examines the runoff response in the Bouhamdane watershed in Algeria using the soil and water assessment tool (SWAT). The SWAT model is applied for the Bouhamane watershed, which includes three sub-watersheds and 45 Hydraulic Response Units (HRUs). To assess the ability and effectiveness of the model, one-gauge station in the basin (sabat) was chosen. Monthly discharge flow data are sourced from Algeria's National Water Resources Agency (NWRA). The soil and water assessment tool calibration uncertainty programs (SWAT-CUPs) with the sequential uncertainty fitting (SUFI 2) algorithm were used to calibrate and validate the model. The model was run from 1985 to 2004, with a calibration period between 1985 and 1994 and a validation period between 1995 and 2005. The model's runoff simulation efficiency has been improved by adjusting watershed input parameters. The SWAT model's performance was assessed statistically (coefficient of determination [R2], Nash-Sutcliffe Efficiency Coefficient [NSE], and Percent BIAS [PBIAS]). The monthly calibration R2, NSE, and PBIAS were 0.89, 0.68, and 43, respectively, and the monthly validation R2, NSE, and PBIAS were 0.78, 0.76, and 10.4, respectively. These results support that the SWAT model is an effective tool for simulating the surface runoff of the Bouhamdane watershed.

Land use and land cover changes in coastal cities can influence drainage sys-tems in ways that affect surface overflows and the infiltration potential of a land surface, making flooding one of the drivers. This research aims to demonstrate the spatiotemporal dynamics of LULC and their combined impact on rainfall and flood height in Skikda, Algeria. The research uses remote sensing (RS) and geographic information systems (GIS) to determine the type and location of LULC changes in Skikda. The supervised classification methodology used the maximum likelihood technique (MCL). Changes were identified in five categories: built-up areas, green spaces, bodies of water, agriculture, and vacant land. In Q-GIS 3.28.2, Landsat 4-5 (TM) data from 1984 and 2004 and Landsat 8-9 (OLI)/TIRS data from 2019 were used based on the United States Geological Survey (USGS). The results show that the impervious built-up area has changed significantly (44.01%) due to massive urbanization and rapid industrialization, which would affect heavy rainfall activity and increase flood height due to the intense imperviousness of the affected soil (from 27% to 44%). The precipitation and flood height were examined and compared with observations to investigate the impact of the LULC model modification during the flood. The comparison of three flood events (1984, 2004, and 2019) revealed that the change in the LULC model is the main factor increasing flood risk in the study area. This study demonstrates the importance of considering temporal changes in land use, land cover, rainfall, and flood height when mapping floods in urban cities.

In recent years, double perovskite oxides have gained attention as promising candidates in the realms of solar cells and catalysis. By adjusting their composition and engineering the band gap, numerous materials are being developed for energy-related applications. Oxide perovskites offer the benefit of a longer carrier lifetime compared to halide perovskites, which is advantageous for energy applications. In this study, we present a systematic theoretical analysis of a double perovskite oxide, examining his composition. The associated electronic and optical properties are discussed, along with prospects for identifying highly efficient materials within this family. This paper reports the study of electronic and optical properties of double perovskite oxide LaFeWO6 by utilizing the FP − LAPW method within the framework of (DFT). Results of density of states and energy bands are presented. The direct band gaps have been found for the systems by using the GGA approximation. Calculations of optical properties is also presented by considering the variations of optical parameters as a function of incident photon energy. The results indicate that LaFeWO6 exhibits a suitable band gap (0.71eV) for visible light absorption, along with promising electronic properties, making it a candidate for photocatalytic and photovoltaic applications.

Cardiovascular (CV) disorders and obstructive sleep apnea (OSA) are very prevalent diseases worldwide. Multiple studies have demonstrated that OSA is associated with increased CV risk. Clinicians need to assess the CV risk to select the proper OSA treatment. A growing number of research have employed machine learning to predict CV risk by integrating clinical and sleep features. In this paper, a multiple input deep learning model was proposed to directly use sleep signals combined with clinical features. Data from 5,506 patients from the Pays de la Loire Sleep Cohort, without a history of major adverse cardiovascular events (MACE), investigated for OSA, were used. After a median follow-up of 6.0 years, 613 patients had been diagnosed with MACE according to the French national health system. Following an architecture selection, deep survival convolutional neural networks were computed to assess the MACE risk score. A custom loss function was integrated to consider the follow-up time of each patient. Based on the weights of each model input, a method for interpreting the model was also proposed to show the contribution of signals compared to clinical features. Sleep signals were extracted from a home sleep apnea test. The best results were obtained with the autonomic manifestation signal. An area under the ROC curve of 0.823 was reached. After interpretation of the models, consideration of sleep appeared to be more important in women and in those under 60. This method may help improve OSA patient care by estimating their risk of MACE during sleep diagnosis.

Bibliometric analysis is crucial in understanding the evolution of research trends and knowledge in various fields. This study applies bibliometric analysis to explore the growth of the research paradigm on agility in the FinTech literature, using co-citation analysis and bibliographic coupling of selected articles. Based on this bibliometric analysis, the evolution of research on agility in the FinTech domain has been prepared, focusing on the literature related to FinTech agility between 1984 and 2022. In this study, we also address the limitations of individual analyses from Scopus and Web of Science (WOS) and propose a comprehensive approach by merging the two research databases. The results reveal significant disparities between authors, publication influences, and keyword occurrences between the WOS and merged databases. Our research highlights the importance of combining a database approach in bibliometric studies, providing valuable insights for scholars, researchers, and stakeholders. Finally, the in-depth bibliometric analysis demonstrates the significance of “FinTech agility” in the rapidly evolving FinTech sector. Financial technology companies’ agility, or ability to adapt quickly, is the foundation of their success and innovation.

In this paper, an efficient algorithm is proposed for solving one dimensional time-space-fractional telegraph equations. The fractional derivatives are described in the conformable sense. This algorithm is based on shifted Chebyshev polynomials of the fourth kind. The time-space fractional telegraph equations is reduced to a linear system of second order differential equations and the Newmark’s method is applied to solve this system. Finally, some numerical examples are presented to confirm the reliability and effectiveness of this algorithm.

The adsorption of chromate ions H2-yA (y = 1, 2, and A = CrO42–) on iron(III) hydroxide was conducted as a function of adsorbent mass, solution pH, and hydration time. The surface complexation technique, based on the examination of the chromate distribution between the solid and liquid phases, was adopted to predict the adsorption mechanism. To specify stoichiometry of the chromate surface complexes, the proton (n > 0), and hydroxyl (n < 0) ion-exchange was evaluated at a pH range of 2–12. The obtained “n” values are ranging between -1 and 1. As a result, the sorption process involved specific chemical interaction with surface sites, resulting in 1H+ and 1OH– release of the adsorbate molecule. The surface species identified were ; ; ; ; ; ; ; and . The logarithmic values of their complexing constants were: log K00 = 1.81 ± 0.04; log K11 = -3.53 ± 0.07; log K21 = -1.03 ± 0.23, log K1-1 = 7.15 ± 0.14 and log K2-1 = 9.62 ± 0.53. The results showed that the chromate adsorption on Fe(III) hydroxide was of electrostatic and chemical nature at pH lower than 5.5, and only of chemical nature at pH superior to 5.5. Taking into account these considerations, Fe(III) hydroxide could be considered an excellent sorbent for the removal of Cr(VI) from wastewater solutions.

This work presents a miniaturized rectangular patch Antenna with negative permeability metamaterial unit cell etched on the ground plane of a conventional patch antenna operating at 3.3 GHz. The new compact metamaterial (MTM) antenna is resonating at 2.45 GHz. It is 44,82% smaller than a conventional rectangular patch antenna resonating at 2.45 GHz and has a bandwidth of 183.3 MHz, a reflection coefficient of -45,36 dB and a gain of 1.37dB, the materials used for the conception are FR-4 dielectric as a substrate, its permittivity is 4.4 and cooper annulled as metal for radiating element and the ground plan, the simulation of the antenna was done with CST solver.

A travers ce travail, nous nous intéressons aux déterminants du comportement de fidélité des clients envers leur banque. Certes, la pratique d’une bonne gestion de la relation client (GRC) par les banques portera ses fruits quant à la création de sentiments de satisfaction, d’engagement et de confiance chez les clients. Mais qu’en est-il de la nature de cette fidélité ?

Mediterranean plants, such as fig and olive leaves, are well-known to exert beneficial effects in humans because of the presence of a wide range of bioactive compounds. However, scarce information regarding the impact of extraction methods, such as ultrasound and types of solvents, on their profile of antioxidant and anti-inflammatory compounds is provided. In addition, no information is available on the effects of extraction methods and solvents on the inhibition of pathogenic bacteria or promoting probiotic growth. In this scenario, this study was aimed to study the effects of ultrasound-assisted extraction (UAE) and solvent on the phenolic profile (Triple TOF-LC-MS/MS), antioxidant and anti-inflammatory compounds of olive and fig leaves. Results showed that UAE extracted more carotenoids compared to conventional extraction, while the conventional extraction impacted on higher flavonoids (olive leaves) and total phenolics (fig leaves). The antioxidant capacity of aqueous extract of fig leaves was three times higher than the extract obtained with ethanol for conventional extraction and four times higher for UAE. In general terms, hydroethanolic extracts presented the highest bacterial growth inhibition, and showed the highest anti-inflammatory activity. In conclusion, these side streams can be used as sources of bioactive compounds for further development of high-added-value products.

The paper presents experimental results concerning the ultrasonically-assisted extraction of bioactive compounds from Erodium glaucophyllum roots. A comparison with conventional methodology is presented, and thereby the phytochemical composition and the antioxidant and anti-inflammatory activities of extracts are evaluated. The phenolic profile of Erodium extracts was analyzed by TOF–LC–MS–MS. The identification of phenolic compounds revealed that the major component was (+)-gallocatechin in the aqueous extracts obtained for the different extraction methodologies. The highest quantity of phenolic compounds and antioxidant capacity was found in the hydroethanolic extract obtained by conventional extraction (29.22–25.50 mg GAE/g DM; 21.174 mM Trolox equivalent). The highest content of carotenoids, varying from 0.035 to 0.114 mg/g dry matter, was reached by ultrasonic-assisted extraction. Furthermore, Erodium extracts showed a potent inhibition of the inflammatory reaction by means of the inhibition of tumor necrosis factor-alpha (TNF-α). The extracts obtained when ultrasound extraction was combined with ethanol:water (50:50, v/v) presented the greatest inhibition (92%).

Cet article se propose de vérifier l’impact de la qualité du service, la satisfaction, l’engagement et la confiance sur le comportement de fidélité chez les jeunes Marocains clients des multinationales de restauration. McDonald’s pris comme exemple. Dans le contexte Marocain, les résultats ont été complètement différents des résultats des études similaires faites dans d’autres contexte différents

In this paper, a bi-objective mixed integer programming model is proposed to deal with the production-distribution problem found in a dairy company in Morocco. The supply chain containing three echelons: multi-sites, multi-distribution centers and multi-customers. The model seeks to integrate two conflicting simultaneous objectives: maximizing benefit by considering the shelf life of products and the total cost (quantitative objective), including production, storage, and distribution, as well as maximizing the service level (qualitative objective), which relates to providing satisfactory services to customers. This is subject to several technological constraints that typically arise in the dairy industry, such as sequence-dependent changeover time, machine speed and storage capacity. Due to imprecise aspiration levels of goals, an interactive approach is proposed based on fuzzy goal additive variants to find an efficient compromise solution. Numerical results are reported to demonstrate the efficiency and applicability of the proposed model.

Abstract In this paper, the behavior of Coplanar Waveguide (CPW) fed SIERPINSKI curve fractal antenna is studied. The results show that there is a relationship between the iteration number and the resonance frequencies. With increase in the number of iteration the resonance frequency decreases with a constant ratio. The use of fractal structures to design antennas makes them more miniaturized. The simulated results obtained from CADFEKO a Method of Moments (MoM) model based Solver and measurement using Vector Network Analyzer Anritsu MS2026C are in good agreement.