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This paper aims to design an AI-based drone that can facilitate the complicated and time-intensive control process for detecting healthy and defective solar panels. Today, the use of solar panels is becoming widespread, and control problems are increasing. Physical control of the solar panels is critical in obtaining electrical power. Controlling solar panel power plants and rooftop panel applications installed in large areas can be difficult and time-consuming. Therefore, this paper designs a system that aims to panel detection.

This paper designed a low-cost AI-based unmanned aerial vehicle to reduce the difficulty of the control process. Convolutional neural network based AI models were developed to classify solar panels as damaged, dusty and normal. Two approaches to the solar panel detection model were adopted: Approach 1 and Approach 2.

The training was conducted with YOLOv5, YOLOv6 and YOLOv8 models in Approach 1. The best F1 score was 81% at 150 epochs with YOLOv5m. In total, 87% and 89% of the best F1 score and mAP values were obtained with the YOLOv5s model at 100 epochs in Approach 2 as a proposed method. The best models at Approaches 1 and 2 were used with a developed AI-based drone in the real-time test application.

The AI-based low-cost solar panel detection drone was developed with an original data set of 1,100 images. A detailed comparative analysis of YOLOv5, YOLOv6 and YOLOv8 models regarding performance metrics was realized. Gaussian, salt-pepper noise addition and wavelet transform noise removal preprocessing techniques were applied to the created data set under the proposed method. The proposed method demonstrated expressive and remarkable performance in panel detection applications.

To evaluate in the first stage, the efficiency of changing the nature and the length of diols on the properties of perfectly hard sequences polyurethanes (PU). In the second, the thermal properties of a new series of segmented PU with different concentrations of soft sequences were determined.

The synthesis of segmented PU has been realised in two stages known as the pre‐polymer method. Various compositions of PU were obtained by keeping the poly(tetramethylene glycol) – PTMG molecular weights constant, but varying its concentration. The products obtained were characterised by IR, NMR, gel permeation chromatography and studied by differential scanning calorimetry.

The level of phase segregation depends on several parameters, especially the nature of the soft segment and its average molecular weight, nature of the hard sequence and the number of hydrogen bonds established in the PU sequences.

The segmented PU obtained were synthesised from PTMG of number molecular weight 2,000. They could also be synthesised from PTMG of molecular weight 600, 1,000, 2,000, 4,000, etc. The effect of change of PTMG molecular weight on PU properties could also be studied.

Better understanding of the morphology of segmented PU and its effect in the practical domains.

Novel perfectly hard sequences PU have been synthesised and characterised. The effect of soft sequence nature and concentration on the phase segregation in these new series of segmented PU is discussed.

The inhibition effect of Foeniculum vulgare seeds’ (FVS) extract on the corrosion of mild steel in acidic medium was studied using weight loss, electrochemical impedance spectroscopy and Tafel polarization, as well as the surface morphology of the mild steel.

Weight loss measurements, potentiodynamic tests, electrochemical impedance spectroscopy studies and gas chromatography/mass spectrometry and scanning electron microscopy analysis of FVS extract were performed.

FVS extract acts as a good inhibitor for the corrosion of mild steel in 1.0 M HCl. The inhibition efficiency increases with the increase in inhibitor concentration but decreases with the increase of temperature.

FVS extract was observed to play an important role in the corrosion inhibition of mild steel in acidic solution.

This paper is intended to be added to the family of green inhibitors which are highly efficient inhibitors and can be used in the area of corrosion prevention and control.

The purpose of this paper is to evaluate the performance of polypropylene glycol (PPG), as a corrosion inhibitor for aluminium corrosion in 0.5 M H₂SO₄ solution at 303-333 K and the effect of addition of iodide ions on the corrosion inhibition efficacy of PPG.

The corrosion inhibition performance of PPG alone and on addition of iodide ions in the acid medium was evaluated using weight loss and electrochemical [electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR) and potentiodynamic polarization (PDP)] methods as well as surface analysis approach at 303-333 K. The morphology of the corroding aluminium surface without and with the additives was visualised using scanning electron microscopy (SEM). The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption.

Results obtained showed that PPG moderately retarded the corrosion of Al in 0.5 M H₂SO₄ solution. Addition of KI to PPG is found to synergistically improve the inhibitive ability of PPG. From the variation of inhibition efficiency, K_ads, and E_a, with rise in temperature, physisorption mechanism is proposed for the adsorption of PPG and PPG + KI onto the Al surface in 0.5 M H₂SO₄ solution. Polarisation results showed that PPG and PPG + KI acted as mixed type inhibitor. The adsorption of PPG and PPG + KI, respectively, onto the metal surface followed El-Awady et al. adsorption isotherm model. SEM and water contact angle analysis confirmed the adsorption of PPG and PPG + KI on Al surface.

The research is limited to aqueous acid environment in aerated condition, and all tests were performed under static conditions.

The use of PPG as corrosion inhibitor for Al corrosion in acidic medium were reported for the first time. The results suggest that iodide ions could be used to enhance corrosion protection ability of PPG which could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the synergistic effect of iodide ions addition to polymer to control acid-induced corrosion of metal.

The use of PPG as corrosion inhibitor for Al corrosion in acidic medium were reported for the first time. The results suggest that iodide ions could be used to enhance corrosion protection ability of PPG which could find practical application in corrosion control in aqueous acidic environment. The data obtained would form part of database on the synergistic effect of iodide ions addition to polymer to control acid-induced corrosion of metal.

The inhibition of corrosion of steel in 1 M HCl solution by newly synthesised pyrazole derivatives has been studied by weight loss and polarisation techniques at 308°K. Its inhibitory power is compared to N,N′‐bis(3,5‐dimethylpyrazol‐1‐yl‐methyl)‐pentanolamine (Bipyr). The results obtained reveal that tripyrazole exhibits a good protection. Inhibition is found to increase with increase in inhibitor concentration. The inhibition behaviour of the compound has been explained on the basis of molecule size and charge density of adsorption active centres. The adsorption phenomenon obeys the Langmuir adsorption isotherm model.

This paper aims to investigate the corrosion inhibition effects of indole-3-carbaldehyde and 2-methylindole on mild steel in 1 M HCl solution.

Indole-3-carbaldehyde and 2-methylindole as corrosion inhibitors of mild steel in 1 M HCl solution were investigated by polarisation and electrochemical impedance spectroscopy (EIS). Adsorption isotherm and mechanism were calculated. Quantum chemical calculations were used to find out a correlation between electronic structure of inhibitors and inhibition efficiency. Changes in the properties of metal surface in HCl solution in the presence of inhibitors were studied by contact angle measurements.

Polarisation results revealed inhibitors could reduce cathodic and anodic reactions rates on metal surface. EIS analysis showed that inhibition efficiency of indoles increases by increasing the inhibitors’ concentration; maximum inhibition efficiency was 95 and 94 per cent in solutions containing 1 mM indole-3-carbaldehyde and 2-methylindole, respectively. Inhibitors’ adsorptions on metal surface were confirmed by analysing the exposed metals’ surface through contact angles measurements. The adsorption of inhibitors was found to follow Langmuir isotherm. Quantum chemical calculations showed that a more positively charged benzene ring in the structure of two indole-based inhibitors would lead to higher adsorption to metal.

This research was carried out to understand the effects of two different functional groups (-C=O, -CH3) with different induction effects on the indole structure and on inhibition efficiency of corrosion inhibitors with the purpose of using these components in industrial application as acid wash solutions to etch and remove rusts from metal surfaces.

The purpose of this paper is to evaluate the effect of thiourea (TU) on corrosion resistance property for rolled and recrystallized E-34 microalloyed steels by using electrochemical polarization techniques.

To perceive the effect of TU on the corrosion inhibition efficiency, various concentrations of TU (from 1 × 10 − 4 to 1 × 10 − 2M) and different temperatures (20, 30 and 400°C) in 1N sulfuric acid are used.

It is found that TU has significant inhibition effect on corrosion process. Moreover, it reveals that both the inhibitor concentrations and temperatures have a strong influence on the corrosion prevention efficiency of inhibitor. Thermodynamics studies confirm that the inhibitor adsorption follows the Langmuir adsorption isotherm model.

To the best of the authors’ knowledge, it is the first work that has been disclosed the corrosion inhibitory effect of TU for recrystallized E-34 microalloyed steels in acidic media.

The purpose of this study was to investigate cimetidine as corrosion inhibitor of aluminium in hydrochloric acid medium.

Cimetidine was characterized by gas chromatography mass spectrophotometer and Fourier transform infrared spectroscopy to determine its chemical composition and functional groups, respectively. Gravimetric, potentiodynamic polarization and electrochemical impedance spectroscopic techniques were used in the corrosion inhibition process. Thermodynamic and adsorption parameters were evaluated. And response surface methodology was used to optimize the corrosion inhibition process.

Analysis of the results revealed that major constituents of cimetidine include metronidazole, n-hexadecanoic acid cyclohexane and methyl ester. It has C-H stretch, C = N stretch, CH₃C-H bend, ring C = C stretch, -C-O-O stretch, N-H bend, C-O stretch and C-H bend as predominant functional groups. Adsorption of molecules of the inhibitor on the aluminium surface was spontaneous, and it followed mechanism of physical adsorption. Response surface methodology revealed that quadratic model adequately described the inhibition efficiency of cimetidine as function of inhibitor concentration, temperature and time. Chemical and electrochemical results are in agreement that the cimetidine is a viable corrosion inhibitor. Cimetidine was revealed as mixed-type inhibitor because it controlled both cathodic and anodic reactions.

Empirical and optimization studies of cimetidine drug as corrosion inhibitor of aluminium in hydrochloric acid medium were carried out. The research results can provide the basis for deploying drugs (with mucosal protective and antacid properties) for corrosion control of metallic structures.

This paper aims to assess the prevalence of vitamin D deficiency among female university students and employees at the Hashemite University (HU) and, then, to identify risk factors for developing vitamin D deficiency among this population. Vitamin D deficiency remains widespread in many countries, including Jordan, and has been linked to many diseases.

In this cross-sectional study, blood samples were taken from 320 healthy females – 160 students and 160 employees – aged between 18 and 65 years old who presented for routine checkup at the medical center of HU. Level of direct sun exposure and barriers to getting enough sunlight (dress style, skin color and sunscreen use) were questioned. Serum levels of 25-hydroxyvitamin D were measured, and the daily intakes of vitamin D, calcium and phosphorous were estimated through completing an adopted food frequency questionnaire. All required data were collected using a face-to-face interview by trained dietitians. The software package ESHA was used to determine the daily intake from the nutrients.

The prevalence of vitamin D deficiency (25-OHD < 25 nmol/L) was 31.2 per cent in female students compared to 20.5 per cent in female employees. Prolonged exposure to sun was independently related to vitamin D deficiency (odds ratio = 4.55); participants exposed for 30 minutes daily were at a higher risk for vitamin D deficiency. However, estimated vitamin D intake was not affected by age and working status.

The present study has some important limitations. First, this study based on serum 25-OHD results, which alone, without biochemical parameters such as parathyroid hormone (either primary or secondary), might be linked to accelerated degradation of 25-OHD and shorter half-life. Second, the half-life of 25-OHD was not consistently available. Third, the smaller sample size of participants. Finally, the present study did not distinguish between intake of vitamin D2 and D3. This limitation caused the inability to precisely evaluate the prevalence of vitamin D deficiency in the studied population.

This study indicates that it is crucial to create awareness concerning the daily intake of vitamin D in the community to avoid long-term complications related to vitamin D deficiency, by using urgent measures including vitamin D supplementation and fortification of some highly consumed food, milk and other dairy products. Educational endeavors about sensible sun exposure should be implemented to improve vitamin D status among this population. The findings of the present study call for action at the national level to build strategies for health promotion about vitamin D supplementation in groups at risk for low supplementation (e.g. younger female students, with previous chronic diseases and poor sun exposure), and engage these populations in strategizing for successful and demographically relevant outreach and education in their own communities along with effort to prevent obesity and diabetes as well as raising awareness through simple programs to prevent and treat vitamin D deficiency among women living in Jordan.

The high prevalence of vitamin D deficiency among female university students in this study emphasizes the necessity of vitamin D supplementation and calls for action to build strategies for health promotion concerning vitamin D supplementation.

This article aims to study the determinants of e-learning acceptability by university students based on their experiences with distance learning during the coronavirus disease 2019 (COVID-19) pandemic.

A questionnaire was used to collect data from 448 students enrolled in a Moroccan business school's fourth and fifth years. The technology acceptance model (TAM) was the primary framework used for this analysis, into which variables from the expectation confirmation model were injected, namely facilitating conditions, social influence, expectation confirmation and satisfaction. The proposed conceptual model was tested and evaluated using the partial least squares structural equation modeling (PLS-SEM) technique. Then the authors have offered an in-depth analysis by employing the importance-performance map analysis (IPMA) approach.

The investigation suggested that the proposed measurement scale effectively assesses the factors impacting students' decision to continue using e-learning in the future. This study’s results show that e-learning acceptance depends significantly on the students' satisfaction, perceived ease of use (PEU) and perceived usefulness (PU). In contrast, the facilitating conditions are not a valid measurement scale to determine students' attitudes toward e-learning.

This is one of the first studies in the Moroccan context to evaluate e-learning acceptability by management students after COVID-19 using a unique research model.