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While there are some hydrogen refueling stations (HRS) functioning in different parts of the world, their use is not widespread enough, primarily due to their expensive cost. Hydrogen compression is a main contributor to the capital and operation costs of the HRS. By improving H2 compression technology, it is possible to optimize the infrastructure for refueling with hydrogen in terms of cost and performance. The use of metal hydride hydrogen compressors (MHHCs), which have the potential to be inexpensive and have the ability to use waste heat and renewable energy sources for the H2 compression, is a promising solution to overcome this issue. The duration of the H2 compression cycle is nevertheless a serious challenge due to the metal hydride (MH) bed's low heat conductivity. As a heating technique to improve the performance of MHHCs, electromagnetic induction (EMI) is examined numerically for the first time in this work. The dynamic behavior of a two-stage MHHC with each MH reactor having an external heat exchanger and being ringed by a copper coil traversed by an alternating current is described by a two-dimensional mathematical model, which was established and successfully verified by the reference data. Numerical simulations were performed with the help of this model, and the findings showed that the EMI heating method is faster than the heat transfer fluid (HTF) heating technique. For instance, at a delivery temperature of 373 K and a supply pressure of 20 bar, it is possible to produce 106 NL H2 per kilogram of HPMH at a pressure of 97 bar with a 74 % shorter compression time than with the HTF heating technique.

The present study aims to assess the technical feasibility of a novel Metal Hydride-based Solar Thermal Collector (MH-STC) system. This system includes a flat-plate solar collector integrated with a metal hydride bed, a hydrogen compressor, a photovoltaic panel, a hydrogen tank, and a water storage tank. This system combines the principles of a conventional solar thermal collector with the energy storage capabilities of metal hydrides, enabling the storage of surplus thermal energy. The LaNi5 alloy was used as heat storage material. A 3D-mathematical model is established and a numerical code written in Fortran-90 is developed to simulate the dynamic behavior of the proposed solar thermal collector. It was shown that the developed 3D-model produces computational results that are consistent with experimental data. In addition, to check the accuracy of the mathematical model and numerical approach, the relative errors in the mass balance and energy balance were calculated and values of 0.054 % and 0.18 %, respectively, were obtained.The simulation results offer insights into the system's technical feasibility, revealing an overall efficiency of 90.6 %, the water temperature at the collector outlet can reach 357.3 K, and a water volume heated of 230.4 L under the considered operating conditions. Moreover, the results indicate that the proposed MH-STC system exhibits significant potential as a viable alternative for thermal storage in domestic hot water systems.

In this research, a numerical simulation was undertaken to assess the effectiveness of an Evacuated tube solar collector (ETSC). The study explored the efficacy of merging a parabolic trough solar collector (PTSC) and copper fins into the U-tube ETSC design. Two types of fins, namely annular fins and disk-shaped fins, were evaluated. Additionally, the study aimed to analyze the influence of operational and geometric parameters, such as the heat transfer fluid (HTF) mass flow rate and the U-tube bend radius, on the performance of the U-tube ETSC. Furthermore, a comparative examination was carried out to identify the most suitable type of phase change material (PCM) for the U-tube ETSC. Finally, a comparative analysis was conducted to assess the performance of the U-tube ETSC in comparison to that of the coaxial tubes ETSC. The results clearly demonstrated that the integration of an PTSC, PCM, and disk-shaped fins substantially improved the overall performance of the ETSC in comparison to the conventional solar collector. This improvement led to a remarkable increase in energy efficiency, with an impressive gain of 42.94 %. The ETSC displayed remarkable performance, particularly at lower HTF mass flow rates and a reduced U-tube bend radius, achieving an average HTF temperature of 430 K. Additionally, among the tested PCMs, RT 82 emerged as the most suitable choice, providing an energy gain of 9.27 % in comparison with the case without PCM.

Thermal energy storage is necessary for concentrated solar power (CSP) plants; it's a useful technique for reducing fluctuations in the energy supply and aids in peak demand management. Therefore, in the present paper, a novel Hybrid Cascaded Thermal Energy Storage (Hyb-CTES) unit is proposed for use in solar-driven Rankine steam power plant. The concept of the heat storage hybridization examined in this study is to couple metal hydride-based thermochemical heat storage system with cascaded phase change materials-based latent heat storage. To assess the dynamic behavior of the Hyb-CTES unit, a two-dimensional transient model is established, and a computational code is developed. The mathematical model has been validated successfully by comparing it with experimental data and by verifying both the mass and energy balance. To choose the appropriate PCM's melting temperature, four approaches are proposed and tested. Numerical simulations were performed with the help of the developed computer code, and the findings demonstrated that the supplied hydrogen pressure and the temperatures of the metal hydride beds are the crucial parameters for determining the PCM melting temperature. In addition, it is found that the proposed cascaded PCMs configuration enhances the heat storage unit's thermal performance and can reduce the heat charge/discharge cycle duration by 19 %. Also, the results indicate that the new Hyb-CTES unit is a promising alternative for thermal storage for CSP plants.

This study aimed to investigate and identify circulating Capripoxviruses in different regions of Morocco, using RT-PCR technique on various sample types. The results from the analysis of 980 samples lend considerable perceptions highlighting the diversity in outcomes across the tested samples. The analysis of Ct values revealed distinct patterns dependent on the nature of the sampled materials. Notably, scab samples exhibited lower Ct values indicating a higher concentration of viral load. Swab samples, in contrast, presented average Ct values signifying a moderate presence of viral DNA. Blood samples demonstrated Ct values within the range suggesting a lower viral load in the bloodstream. Furthermore, the study also revealed endemic Capripoxvirus outbreaks in Morocco, particularly in regions with a strong sheep breeding industry.

This study aims to determine which thermal energy storage (TES) system is most suited for a concentrated solar power (CSP) plant. The question is which the best TES system, whether utilizing a single metal hydride or employing dual metal hydrides with or without reaction heat recovery via phase change material (PCM). The authors noted that no studies have been conducted to address this question thus far. Consequently, the primary aim of this paper is to compare three different TES systems in order to ascertain the viability, efficacy, and performance of the appropriate TES system. The examined TES systems included: (i) TES system 1, based on a single metal hydride tank coupled to a hydrogen tank through an H2 compressor; (ii) TES system 2, based on paired metal hydride tanks without recovering reaction heat; and (iii) TES system 3, based on paired metal hydride tanks incorporating a PCM for reaction heat recovery. To simulate and evaluate the performance of the three TES systems under various operating conditions, a mathematical model and computer program were created and successfully verified. By examining into their thermodynamic performance and practical viability, this study attempts to provide the strengths and limitations of each system. A comparison of the three TES systems' performance indicators indicates that the TES system 1 has the potential to provide a specific power output of 500.8 W/kg of alloy, which is 50.1 % and 76.4 % greater than the TES systems 2 and 3, respectively. With a volumetric storage capacity of 755 MJ/m3, the TES system 2 outperforms the other two TES systems by around 40 %. The TES system 3 can operate with 85.9 % energy storage efficiency. This efficiency is 30.3 % higher than that of the TES system 1 and 10.2 % higher than that of the system 2. Ultimately, the decision to choose either a TES system based on a single metal hydride or one involving paired metal hydrides is hinges on the specific requirements, limitations, and priorities of the TES system under consideration.

This article delves into the intricate world of controlling the longitudinal dynamics of autonomous vehicles. In the first part, we studied two distinct controllers: the Super Twisting Sliding Mode Control and its modified version enriched with the integration of fuzzy logic, applied to the longitudinal dynamics of the autonomous automobile to follow a desired speed longitudinal profile, the two controllers are compared with a Neural Network-Based Non-singular Terminal Sliding-Mode Control, the system takes the throttle and brake as its inputs and delivers speed and acceleration as outputs. The overarching objective is to ensure that the controlled vehicle maintains a close and precise alignment with the desired speed profile. The second part of our research is dedicated to the development of adaptive cruise control systems and cruise control according to the safety conditions. This controller consists of two blocks low and upper controller, in upper controller the inputs are the speeds of the automobile in front and of the autonomous automobile itself, the safety distance, the measured distance. The output is the desired acceleration. The objective is to maintain a distance between the front vehicles, greater than or equal to the safety distance. For this, to achieve this task, we have implemented a control system known as the Proportional Integral Derivative (PID) controller in the adaptive cruise control system to control this system. In the low controller block, the same controllers used in the first part: the Super Twisting Sliding Mode Control and its modified version based on fuzzy logic, are applied, the system inputs are throttle and brake, and the outputs are speed and acceleration. This system is processed by MATLAB code, we obtained a better result with our proposed controller such that the maximum absolute speed error is equal to 0.0144 m/s in the first case of speed tracking, and to 0.006 m/s in the second case of the using adaptive cruise control, the illustrations below show the efficiency and robustness of these controllers.

Introduction The interface between dermatology and psychiatry is complex and of clinical importance. Skin disorders in psychiatric inpatients are common, serious and under diagnosed. Objectives The aim of our study was to assess the prevalence and profile of several skin diseases observed in psychiatric inpatients. Methods We conducted a cross-sectional study in the period from october,13 2023 to october,20 2023, among psychiatric male inpatients, hospitalized in psychiatry B department of the Hedi Chaker University Hospital (Sfax, Tunisia). We collected sociodemographic and clinical data using a pre-established form. Results Over a period of a week, 35 patients were included in our study. The mean age of patients was 39,97 years. Among them, 80% were single and 14,3% were married. Addictive behaviors were reported in 74,3% of cases. The level of hygiene was good in 74,3% of patients. The three most common psychiatric diagnoses were schizophrenia (31,4%), followed by bipolar disorder (28,6%) and schizoaffective disorder (25,7%). We recorded 13 cases of skin diseases (37,2% of patients). Dermatological lesions were dominated by traumatic origin in 14,3% of cases. They were of infectious origin in 11,4% of cases, immunoallergic in 8,6% and parasitic in 2.9%. Conclusions The prevalence of skin diseases is high in psychiatric inpatients, for whom proper skin care is necessary to improve their quality of life. Disclosure of Interest None Declared

Introduction In the medical field, work addiction is a double-edged phenomenon. It can be regarded as a positive addiction leading to high motivation to work, but it can also have adverse mental, physical, and social consequences. Objectives To assess the relationship between work addiction and perfectionism in trainee doctors. Methods We conducted a cross-sectional descriptive and analytical study among trainee doctors. We used the “Work Addiction Risk Test” (WART), and “The Big Three perfectionism scale short form”. Results A total of 99 doctors were included. The mean age of participants was 27.6 years, with a sex ratio (M/F) of 0.33. The doctors in our study worked 5.39±1.6 hours a day and were on call 3.84±2.87 times a month. Their average number of hours of sleep was less than 7 hours in 43.4 % of participants. The mean score of the WART was 61.2±14.83. Among the trainee doctors surveyed 39% were considered at high risk of workaholism. The mean WART score was significantly higher among female physicians and those who slept less than 7 hours per day on average. In addition, the average score on the WART scale was significantly associated with the number of calls per month. We found a statistically significant association between perfectionism scores and work addiction scores. Conclusions Our study showed that work addiction is common among doctors in training and is favored by high levels of perfectionism. It is therefore essential to explore and define preventive measures to help them find a balance allowing them to aim for high standards and be able to progress, without setting unrealistic expectations, which can lead to work addiction. Disclosure of Interest None Declared

Introduction Perfectionism is often seen as a beneficial trait for trainee doctors since it means they have high standards and a drive for success. However, it demands a flawless level of performance regardless of one’s physical or mental health and well-being. Consequently, perfectionism is now viewed from a different perspective. Objectives We aimed to study the impact of perfectionism among doctors in training on their self-esteem. Methods We conducted a cross-sectional descriptive and analytical study among trainee doctors. The following psychometric instruments were used: The “Work Addiction Risk Test” and the “Rosenberg Self-Esteem Scale”. Results We included 99 doctors in training. Their mean age was 27.6± 2.2 years. The sex ratio (♂/♀) was 0.33. Most participants were single (63.6%) and of middle socioeconomic level (86%). Tobacco use was reported in 6.1% of cases, and alcohol use in 4.1% of cases. Among all participants, 58 % had low or very low self-esteem. The mean score of Rosenberg Self-Esteem Scale was 30±5.13 and the mean score of the big three perfectionism scale short form was 41.11±13. Higher self-esteem scores was significantly associated with lower self-critical perfectionism scores. Conclusions Our results point to the negative impact of self-critical perfectionism on self-esteem. In fact, perfectionism can hold you back, both personally and professionally. Perfectionists see their own self-worth as tied to what they achieve, and they believe that others judge them on this as well. They can never live up to the standards they set for themselves, and this can lead to a downward spiral of self-criticism and blame. Disclosure of Interest None Declared

Introduction Attachment styles is intrinsically related to the capacity for forming close social bonds, making it a vital lens through which to understand social functioning. Objectives This study investigates the link between attachment styles and social functioning among women diagnosed with schizophrenia. Methods We carried out a descriptive and analytical cross-sectional study from May to June 2023, focusing on stabilized female patients diagnosed with schizophrenia or schizoaffective disorder. The study took place in the ‘B’ psychiatry department of Hedi Chaker University Hospital in Sfax, Tunisia. Data on attachment styles and social functioning were collected using self-report questionnaires: the Revised Psychosis Attachment Measure (PAM_R) and the Social Functioning Scale (SFS). In our study, we employed both the Wilcoxon test for paired samples and the Spearman correlation test to assess the differences and correlations between attachment scores and social functioning scores, respectively. Results In the study, 41 female patients were included. The participants had a mean age of 49.19, ranging from 19 to 79 years old. Attachment styles were predominantly avoidant (60.97%), followed by anxious (24.39%) and disorganized (14.63%). A significant portion, 39%, exhibited low social functioning. The domains most affected were leisure (63.41%) and employment (60.97%). Our analysis revealed negative correlations between avoidant attachment and social functioning in leisure activities (Spearman’s ρ = -0.057, p < 0.05) as well as between avoidant attachment and independence performance (Spearman’s ρ = -0.040, p < 0.05). Also, the correlation coefficient for anxious attachment and leisure activities is 0.041, demonstrating a positive association (p < 0.005). Conclusions These initial findings may imply a potential association between attachment styles and social functioning in schizophrenia. Disclosure of Interest None Declared

Introduction Orthorexia is defined as a dependence on healthy food or an obsession to consume healthy food. One area deemed influential upon disordered eating and dietary intake is perfectionism. Objectives To investigate the relationship between orthorexia and perfectionism in medical students. Methods We conducted a cross-sectional, descriptive, and analytical study in the faculty of medicine of Sfax (Tunisia), between February and April 2023. A self-reported questionnaire was distributed to students via social media. We used ORTO-15 for the assessment of orthorexia, and the Big Three Perfectionism Scale (BTPS) to assess perfectionism. Results The research has enrolled 220 students. Their mean age was 21.40±1.68 years, with female predominance (70%). The ORTO-15 mean total score was 36.88±6.76. A total of 60% of participants had an orthorexic behavior. The BTPS mean total score was 45.52±12.45 with a mean score of 13.25±4.35 for rigid perfectionism, 18.31±6.37 for self-critical perfectionism, and 13.99±5.47 for narcissistic perfectionism. Students with orthorexic behavior had significantly higher scores of perfectionism (p= 0.048). Conclusions Our study has drawn a significant association between orthorexia and perfectionism among medical students. This result suggests that students experiencing highly critical and judgemental beliefs associated with perfectionism are more susceptible to orthorexic eating behaviors. Disclosure of Interest None Declared

Introduction Orthorexia nervosa is defined as an unhealthy obsession with eating healthy food. Recent studies currently demonstrated that students in health-oriented academic programs, highly focused on nutrition and physical exercise, are more prone to develop orthorexia nervosa than students in other educational areas. Objectives Determine the prevalence of orthorexia nervosa in medical students and identify associated factors. Methods We conducted a cross-sectional, descriptive, and analytical study in the faculty of medicine of Sfax in Tunisia, between February and April 2023. We used ORTO-15 for the assessment of orthorexia. Results The research has enrolled 220 students. Their mean age was 21.40±1.68 years, with female predominance (70%). The mean Body mass index (BMI) was 22.46±4.15 kg/m2. The prevalence of overweight (BMI≥25 kg/m2) and obesity (BMI≥30 kg/m2) were respectively 19.5% and 3.6%. Over a third of students (34.1%) were using means of weight control, of which the diet represented 62.66% of cases. The participants had consulted a nutritionist in 11.4% of cases. The ORTO-15 mean total score was 36.88±6.76, with a mean score of 12.95±2.69 for cognitive dimension, 13.31±2.70 for clinical dimension, and 10.61±2.52 for emotional dimension. A total of 60% of participants had a score under the threshold. Orthorexia was significantly associated with female gender (p

Renewable energy has garnered attention due to the need for sustainable energy sources. Wind power has emerged as an alternative that has contributed to the transition towards cleaner energy. As the importance of wind energy grows, it can be crucial to provide forecasts that optimize its performance potential. Artificial intelligence (AI) methods have risen in prominence due to how well they can handle complicated systems while enhancing the accuracy of prediction. This study explored the area of AI to predict wind-energy production at a wind farm in Yalova, Turkey, using four different AI approaches: support vector machines (SVMs), decision trees, adaptive neuro-fuzzy inference systems (ANFIS) and artificial neural networks (ANNs). Wind speed and direction were considered as essential input parameters, with wind energy as the target parameter, and models are thoroughly evaluated using metrics such as the mean absolute percentage error (MAPE), coefficient of determination (R2), and mean absolute error (MAE). The findings accentuate the superior performance of the SVM, which delivered the lowest MAPE (2.42%), the highest R2 (0.95), and the lowest MAE (71.21%) compared with actual values, while ANFIS was less effective in this context. The main aim of this comparative analysis was to rank the models to move to the next step in improving the least efficient methods by combining them with optimization algorithms, such as metaheuristic algorithms.