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Structure's damping force during an earthquake is very different from what was anticipated during design. This adds uncertainty to the process of designing structures exposed to seismic loads which may be a major cause of significant variation in the seismic response reliability of these structures. This work is focused on the investigation of the structural damping uncertainties effect on the structure’s response spectra through the assessment of uncertainties in the damping reduction factors (DRF) derived from the acceleration, velocity and displacement spectra. An Artificial Neural Networks (ANN) was also developed for the stochastic DRF calculation. The Monte Carlo method, one of the methods of computational algorithms that rely on repeated random sampling to obtain numerical results, is used for the estimation of the stochastic DRF. The obtained results indicates that the difference between the deterministic and the stochastic DRF are around of 21 % for displacement and velocity and 28.7 % for acceleration spectra. As a consequence, the DRF derived from the acceleration spectra is more sensible to the uncertainties inherent on damping than the DRF obtained from displacement and velocity. Therefore, it is important to take this conclusion into account when using these factors previously. The ANN constitutes a sample and efficiency method to predict the stochastic DRF since the error obtained is always less than 6 %. Practice oriented results are searched for, to be incorporated in future seismic standards.

This article explores the role of innovation strategies for enhancing the competitiveness of SMEs in global markets. Based on a literature review of innovation strategies, these strategies were separated into four groups: product innovation, process innovation, organizational innovation, and marketing innovation. The study focused only on the product innovation strategy and marketing innovation strategy. The empirical analysis found that Algerian enterprises adopt both a product innovation strategy and a marketing innovation strategy. There are differences regarding the relationship between the product innovation strategy and adding value to the firm compared to the relationship between the marketing innovation strategy and adding value to the firm in Algerian enterprises. Here, there are three positive relationships between product innovation strategy and adding value to the firm whereas in contrast, there are two positive relationships between marketing innovation strategy and adding value to the firm. Thus, the enterprises under study must shift from a product innovation strategy to a marketing innovation strategy, which means focusing their attention more on the latter to market their products more and faster, which allows them to add more value to the company.

This paper is an attempt to analyze the effects of current exchange rate regimes on the economic growth achieved by the MENA countries. To determine in a dynamic perspective new relationships that will be established between growth and exchange rate regimes, we are looking for an answer to two major concerns, namely: the question of the choice of the exchange rate regime and the question of the impact of this choice on economic performance. To reach our objective we first studied the theoretical and empirical literature of the exchange rate regime and then we had to study the evolution of the exchange rate regime in MENA countries. Then, we got an economic model based on the determinants of growth. The data used on this model takes the form of panel data for 5 MENA countries (Algeria, Egypt, Jordan, Morocco, and Tunisia) for the period 1984-2019, as well as, several methods of modeling will be discussed, to finally adopt one from them that best applies to our research goal and shows several possibilities that can be used to apply this model in different ways depending on the country considered. The results reveal that it is very important to take into account the monetary policy framework that accompanies the exchange rate regime when assessing the effects of this regime on the overall performance of the economy.

La rupture utérine est une complication rare du travail qui met en jeu le pronostic vital de la mère et celui du fœtus ainsi que le devenir obstétrical de la femme. Elle est plus fréquente en cas d´utérus cicatriciel et très rare en cas d´utérus sain. Nous présentons un cas rare de rupture utérine spontanée sur utérus sain chez une patiente de 28ans sans antécédents pathologiques notables diagnostiquée après six heures de son accouchement par hémorragie du post partum. Nous discutons à travers ce cas et la revue de la littérature, l'extrême prudence qu'il faut garder même en cas d´utérus non cicatriciel ainsi que les signes d'appel cliniques, les facteurs de risque, la méthodologie diagnostique et la prise en charge thérapeutique de cette entité rare mais potentiellement grave.

The infinite needs of humanity in several fields give birth to several innovations, in materials sciences, these needs are summed up in the creation of new composite materials. Obtaining a composite material from recycled material and a bio-load first of all makes it possible to recover the recycled material and to have new composite material. PVC is one of the most used plastics in recent years, the addition, after recycling, of a bio-load in the form of chicken feathers which are just lost in nature or incinerated, allows the birth of new composite material. In this article, we use neural networks which appear to be among the essential methods to solve and model complex systems, and in particular when it comes to non-linear problems. This method will be used in comparison with the finite element method to find the most adequate method which makes it possible to better model the behaviors of PVC bio-loaded by chicken feathers, and then predict the behaviors with different percentages of the bio-load. We took the results of the experiments carried out, with those of the study of finite elements, and with the results obtained by the neural networks which will be presented in this article, to find the model which makes it possible to better present and predict the behavior of the recycled PVC bio-loaded with an adequate percentage which improves the mechanical characteristics of this type of composite material. The error between the experimental results and those obtained by the neural networks is very small compared to the differences between the two experimental results and those obtained by the finite elements. Which proves that the neural network model is an important computer tool for modeling and predicting the results of mechanical experiments

This research studies the effect of waste marble powder (WMP) as substitute of Portland cement on strength and durability of self-compacting concrete (SCC) in order to produce SCC with reduced impact environmental. For this purpose, five mixtures were designed in which four mixtures contained WMP at substitution levels of 5, 10, 15, 20%, and mixture included only the Portland cement as control mix. The realized tests are compressive strength at 3, 7 and 28 days, water capillary absorption, water absorption by immersion and sulfate attack. The results show a reduction in the compressive strength with increasing WMP content. The use of WMP was found to increase both of the water capillary absorption and water absorption by immersion. SCC containing WMP subjected to magnesium sulfate attack presented a lower expansion and higher resistance to sulfate aggressions.

Abstract Phosphorus chemistry occupies a pivotal position in contemporary organic chemistry but significant synthetic challenges still endure. In this report, a class of electrophilic phosphiranium salts, bearing fluorinated benzyl quaternizing groups, is introduced for the direct synthesis of diversely β-functionalized phosphines. We show that, in comparison with regular quaternary phosphiranium salts, these species display the sought balance of excellent stability and high electrophilic reactivity that allow the unlocking of the C-centered ring-opening reactions with different classes of weak nitrogen-, sulfur- and oxygen protic nucleophiles.

Objective: To conduct an ethnomedicinal survey and conserve traditional medicinal practices in the Mascara region of northwestern Algeria. In this region, traditional medicinal knowledge has primarily been transmitted orally, and the study aims to document it in written form for better utilization in the field of pharmacology. Methods: Purposive sampling with semi-structured questionnaires was adopted with ethnobotanical data obtained from 135 local informants, including 22 herbalists. The study participants were asked about their sociodemographic profiles and ethnomedicinal knowledge about anti-urolithiatic medicinal plants. Results: Sixty-three anti-urolithiatic species belonging to 59 genera and 32 families were inventoried. All plants are prescribed orally, and decoction presents the most common preparation method (46.0%). Seeds are the most used parts (27.0%). The most frequent botanical families were Apiaceae, Lamiaceae, Fabaceae, and Rosaceae. The predominant anti-urolithiatic plants are Herniaria hirsute L., Hordeum vulgare L., Linum usitatissimum L., Zea mays L., Lavandula angustifolia Mill., and Apium graveolens L. Conclusions: This study highlights the diversity of the phytotherapeutic practices used against urolithiasis in the region of Mascara. It also suggests that ethnomedicine is well-entrenched in local health practices in this area. However, this knowledge acquired by the local inhabitants over the centuries risks disappearing since it is mainly held by older people and is not documented.

Self-compacting repair mortars (SCRM) are particularly desired for the rehabilitation and repair of reinforced concrete structures. The properties of SCRM can be improved by using chemical, mineral, polymer and fiber additives. In limestone quarries, considerable quantities of limestone fine powder are obtained during the process of crushing rock. These fine powders are being collected and their utilization is a big problem from the aspects of disposal, environmental pollution and health hazards. The introduction of limestone powder as cement and sand replacement present interesting possibilities to reduce the cement cost production, CO2 emission and the conservation of natural resources. The effects of limestone powder content in crushed sand on the properties of SCRM are not studied. An experimental study was undertaken to find out the effect of limestone powder content on fresh and hardened properties of SCRM. SCRM mixtures were prepared using crushed sand partially replaced with limestone powder at varying percentages up to 30%. Results indicate that the limestone powder as sand replacement significantly improves the fresh and hardened properties of SCRM with a content ranging from 10 to 15%. The use of limestone powder in repair mortar and concrete application would offer technical, economical and environmental advantages for concrete producers.

Abstract Objective To determine the estimated prevalence of anxiety, depression, and anxiety–depression syndrome (ADS) and to identify the associated factors in Moroccan people with epilepsy (PWE). Method A cross‐sectional study was conducted among adult PWE (June 2021–December 2022) in the Casablanca–Settat region. PWE were interviewed by completing a questionnaire collecting sociodemographic and clinical data. Anxiety and depression were assessed by the Hospital Anxiety and Depression Scale (HADS). Out of 21 points, a score ≥8 is in favor of considerable anxiety/depression symptoms and a sum of the two scores ≥15 indicates the presence of ADS. Data were analyzed using Statistical Package for Social Sciences (SPSS) 21.0. p‐values ≤0.05 were considered statistically significant and logistic regression was performed to determine the associated factors. Results Among 294 PWE, the median age was 39 years (interquartile range [IQR]: 25.75–54.00). The median anxiety, depression, and ADS scores were 8 (IQR: 5.00–10.00), 7 (IQR: 4.00–10.00), and 15 (IQR: 10.00–20.00), respectively. Anxiety, depression, and ADS were revealed in 51.4%, 44.9%, and 51.0% of PWE, respectively. Depression was the only predictor for anxiety (aOR = 24.20; 95%CI: 12.45–47.01). Antiseizure polytherapy (aOR = 3.35; 95%CI: 1.72–6.54) and anxiety (aOR = 24.04; 95%CI: 12.12–47.67) were the factors associated with depression. The risk of ADS was increased by female gender (aOR = 2.83; 95%CI: 1.68–4.78), antiseizure polytherapy (aOR = 2.75; 95%CI: 1.62–4.65), structural epilepsy (aOR = 1.73; 95%CI: 1.01–2.94), and the presence of concomitant conditions with epilepsy (aOR = 1.96; 95%CI: 1.16–3.31). Significance Our study reports high psychiatric comorbidity prevalence in epilepsy, which supports the bidirectional link hypothesis. Associated factors found are important in the prognosis and prevention. Plain Language Summary The neural mechanisms underlying epilepsy tend to expose PWE to psychiatric disorders. Our study aims to quantify the rate of psychiatric comorbidities and their predictive factors in Moroccan PWE. The estimated prevalences of significant symptoms of anxiety, depression, and ADS were 51.4%, 44.9%, and 51.0%, respectively. Depression was the predictor of anxiety. Antiseizure polymedication and anxiety were the associated factors with depression. The risk of SAD was increased by female gender, antiseizure polymedication, structural epilepsy, and concomitant diseases with epilepsy. Our results are important for considering the psychiatric aspect of PWE and improving their care and quality of life.

This paper focuses on the characterization of nano-powder (NP) scintillator, specifically presenting preliminary results of the measurement of the light yield (LY) of a newly synthesized Lutetium Aluminum (LuAG) garnet phosphor NP scintillator, doped with 0.1% cerium. The scintillation light yield was measured using the comparative method. Considering the light-scattering and self-absorbing properties of powder scintillators, alpha particles from 241Am source were used for excitation instead of Gamma/X rays, while a Ce3+ activated LuAG single crystal (SC) was employed as the reference detector due to its well-established light yield. A photomultiplier tube (PMT) served as the photodetector, and signals were read out by a nuclear instrumentation chain. The results demonstrate that the newly prepared LuAG:Ce NP exhibits a light output that is approximately 90% of that of the single crystal reference. These findings highlight the promising potential of NP scintillators as a viable alternative to single crystals, especially in applications where the preference for powder scintillators is evident.

Abstract Power systems exhibit nonlinearity. causing dynamic instability and complex power oscillations. This research proposes an innovative strategy using the Novel Bat Algorithm (NBA) to achieve ideal Power System Stabilizers (PSSs) in a multimachine power system. The approach shifts electromechanical modes to specific areas in the s-plane. Enhancing the multi-machine power system and establishing stabilizer parameters for dynamic performance. The study examines the designed approach aptitude for standard lead-lag PSSs configurations. In order to elevate the global search problem and transfer some static operators for the optimum optimization process. the chaos mapping. also known as CNBA. is introduced into NBA. Four different forms of chaos maps are compared in experiments to resolve unconstrained mathematical issues in order to illustrate CNBA performance. In any other case. the challenge of designing PSS under a wide range of loading situations is transformed into an optimization challenge with the damping ratio of electromechanical modes with low damping as the target function. The optimal stabilizers’ gains are gotten by employing the CNBA algorithm. Second plan. an effective technique is astutely established to delineate the PSS location and quantity using CNBA and another side using participation factor. To examine the efficacy of the proposed CNBA-based PSS on a large system; it is tested on the interconnected of New-England/New-York (16 generators and 68 buses) power grid. and verified by comparative study with NBA through eigenvalue analysis and nonlinear simulation to provide evidence the algorithmic competence of CNBA. The CNBA approach yields a minimum damping ratio of 37%. which is consistent with the its eigenvalue. In contrast, the NBA approach achieves a minimum damping ratio of 31%. The simulation results reveal the fine performance of the proposed CNBA-PSS in a convincing manner and its capacity to provide an excellent damping for inter-area and local oscillations under diverse operating cases compared to NBA-PSS then in the case of PSS location.

The purpose of the current research is to inspect the free convection of the nanofluid (Cu–water) within a hexagonal cavity containing a square obstacle with isothermal vertical walls at Th{T}_{{\rm{h}}} and Tc{T}_{{\rm{c}}}, and insulated horizontal walls. The aim of this study is to analyze the interaction between the Rayleigh number (103

This article presents on a multi-institution project that explains the design and development of Virtual Tabadul, an Arabic and English foreign language exchange program amongst 1,200 U.S. and Middle East and North Africa (MENA) college-aged youth. The program involves faculty, staff, and students at four institutions: Florida International University (U.S.), University of Michigan-Dearborn (U.S.), Oum El-Bouaghi University (Algeria), and Ibn Tofail University (Morocco). The project has been developed with generous funding from the Stevens Initiative and is the very first virtual exchange program for Arabic and English foreign language learning in virtual reality.

Gas turbines are essential components in modern naval vessels, providing both propulsion and power for onboard systems. However, their performance can degrade over time due to factors like fouling, erosion, and thermal fatigue, leading to increased fuel consumption and reduced operational efficiency. This paper explores the application of machine learning (ML) techniques for predicting gas turbine performance, focusing on models such as linear regression, support vector machines (SVM), random forests, and gradient boosting machines (GBM). A comprehensive literature review was conducted to assess the strengths and weaknesses of these techniques. The machine learning models were developed, fine-tuned, and evaluated using metrics such as accuracy, root mean squared error (RMSE), and R2. The results demonstrate that ensemble methods, particularly Random Forests and GBM, outperform traditional models in predicting turbine performance, offering robust, accurate, and interpretable solutions for proactive maintenance and operational optimization in naval vessels.

All the factors potentially influencing tacrolimus dose requirement and combinations thereof have never been thoroughly investigated, precluding accurate prediction of tacrolimus starting dose. This prospective, non-interventional, multicenter study in de novo adult kidney transplant recipients over the first year after transplantation aimed to investigate the factors influencing tacrolimus dose-standardized trough blood concentration (C0/D) over the first week post-transplant (D4-D7, primary objective), D8-M3 and M3-M12 (secondary objectives). Statistical analysis employed mixed linear models with repeated measures. Eighteen sites enrolled 440 patients and followed them up for 9.5 ± 4.1 months. Age at baseline (p = 0.0144), end-stage renal disease (p = 0.0092), CYP3A phenotype (p < 0.0001), dyslipidemia at baseline (p = 0.0031), hematocrit (p = 0.0026), total bilirubin (p = 0.0261) and plasma creatinine (p = 0.0484) independently increased with log(C0/D) over D4-D7, explaining together 72.3% of the interindividual variability, and representing a robust model to estimate tacrolimus initial dose. Donor age and CYP3A phenotype were also influential over D8-M3 and M3-12, in addition to recipient age. Corticosteroids, diabetes at baseline, and ASAT yielded inconstant results between D8-M3 and M3-M12. We found no ethnicity effect when CYP3A phenotype was accounted for, and no food effect. Intra-individual variability over M3-M12 was moderate, and significantly lower in patients with chronic hepatic disorder (p = 0.0196) or cancer (p = 0.0132).

Purpose: This study aims to clarify the relationship between the leadership styles of primary school principals and their relationship to the cohesion of the educational group from the point of view of primary education teachers, Design/Method/Approach: The study is considered an experimental study in revealing the styles of administrative and educational leadership of a principal and their relationship to the cohesion of his group of professors, using the descriptive, relational approach. They also conducted a quantitative survey of the data through two questionnaires and ensured their validity and reliability, then applied them to 376 professors. Findings: The model provides a direct relationship between The democratic style of the principals of primary education in the city of Messaad and the cohesion of the educational group from the point of view of teachers, but the delegative Leadership style (Laissez-Faire)and authoritarian don’t affect the cohesion of the educational group from the point of view of teachers. Theoretical implications: This paper presented two important studies related to leadership styles and group dynamics and cohesion to compare them with the results of our current study. The study also indicated a full definition of the terms of the study. Originality/value: This research helps school principals and supervisors adopt the appropriate method in managing their institutions in accordance with the needs and requirements of subordinate teachers to work efficiently and provide the best performance. Research limitations/Future research: This research offers prospects for future research on factors that help maintain group cohesion. Paper type – empirical. Keywords: The democratic; the delegative; the authoritarian; cohesion. JEL Сlassіfіcatіon:, C93, D23, C92, M12

This paper deals with power quality improvement using a three-phase active power filter (APF) connected to a PV power system. This paper deals with power quality improvement using a three-phase active power filter (APF) connected to a PV power system. The DC-DC boost converter acting as an interface within the PV system and the three-phase voltage source inverter. A fuzzy logic maximum power point tracking (MPPT) controller is used to obtain the maximum power from the PV system. Furthermore, the optimal selection of the inverter switching states is realized by combination of direct power control (DPC) and a predictive method. Modelling and simulation of the system were performed by using Matlab/Simulink software.