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This paper demonstrates a water pumping hybrid power system design. The proposed system was designed for water related applications in Sharjah (Latitude 25.29 °N and Longitude 55 °E), United Arab Emirates. The proposed water hybrid system has two primary renewable power systems: solar PV panels and wind turbines. The proposed hybrid system considers the changes in weather conditions (humidity, wind speed, and temperature) since wind speed affects the performance of the wind turbines and solar panels are affected by solar irradiance. The following components are involved in the proposed design: battery (to store the power from solar panels), voltage regulator circuit (for getting stable DC voltage), three-phase rectifier (to convert the reduced AC voltage to DC), three-phase transformer (for reducing the obtained AC voltage), and DC electric motor (the main output of the proposed water pumping system). The proposed water pumping system relies on neural network blocks to achieve weather forecasting by obtaining solar irradiance values from the input temperature, wind speed, and humidity in a span of five years. Both MATLAB and Simulink are used simulate the performance of the proposed system under different weather conditions by changing the values according to the measured weather conditions values over five years.

<span>Dust is one of the significant constraints in utilizing solar photovoltaic systems under harsh weather conditions in the desert regions due to creating a shadow that blocks solar irradiance from reaching solar cells and consequently, significantly reducing their efficiency. In this research, experimental study was performed to comprehend the nature of dust particles and their impact on the electrical power output that is generated from azimuth tracking solar PV modules under Sharjah environmental conditions in winter season. According to laboratory experiments, the power losses are linearly related to the dust accumulated density on the surface of the solar panel with a slope of 1.27% per g/m2. The conducted Outdoor studies revealed that the absolute reduction in output power increased by 8.46% after 41 continuous days with one low-intensity rainy day. The linear relationship obtained from indoor experiments was applied later to estimate the dust deposited density on the outdoor setup. The results showed that a regular cleaning process every two weeks is recommended to maintain the performance and to avoid the soiling loss. This work will help engineers in the solar PV plants to forecast the dust impact and figure out the regularity of the cleaning process in case of single axis tracking systems.</span>

Background: Patients with pulmonary venous hypertension (PVH) secondary to left heart disease can be further classified according to their hemodynamic profile: pulmonary hypertension (PH) in proportion to the pulmonary capillary wedge pressure (PCWP) and PH out of proportion to the PCWP or reactive PH. Currently, there are no measures that enable prediction of the development of reactive PH in patients with left heart disease. Objectives: In this study, we aim to characterize PVH patients with reactive PH as compared to proportional PH in an attempt to create a distinct profile for patients with left heart disease carrying a high risk for the development of reactive PH. Methods: Thirty-three PVH patients with reactive PH and 29 PVH patients with proportional PH were analyzed retrospectively over a 6-year period. Clinical, laboratory, echocardiographic and hemodynamic parameters were noted and compared between subgroups. Results: There was no significant difference between PVH patients with reactive and proportional PH with regard to gender, age (65.91 ± 11.9 vs. 66.69 ± 10.5 years) and body surface area (1.89 ± 0.24 vs. 1.9 ± 0.23 m²). Prevalence of the metabolic syndrome components was similar in both groups. Interestingly, PCWP was similar in both groups, as were the structural and functional parameters of the left heart. Conclusions: PVH patients with reactive PH have a similar profile as patients with proportional PH; consequently, the evolution of reactive PH is unpredictable. Therefore, it is imperative that physicians maintain a high index of suspicion for the development of reactive PH even in the early stage of heart disease.

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<p>There are many water pumping power systems that exist nowadays relying on conventional and renewable energy sources such as mechanical windmills, solar photovoltaic (PV) panels, wind turbines, and diesel generators. Few designs utilize thermoelectric modules for the purpose of enhancing the reliability and the performance of the system in order to provide water supply to isolated zones continuously. The use of thermoelectric (TE) modules is increasing due to their reduced prices and the possibility of using them in different applications depending on the required specifications of motors and other connected loads. This paper proposes a renewable energy system design for water pumping applications in Sharjah (Latitude 25.29°N and Longitude 55°E), United Arab Emirates. The system involves TE modules for operating the three-phase AC water pumping motor, voltage regulator, voltage boost converter, and three-phase power inverter while considering the changes of temperature values which affect the performance of the thermoelectric generator (TEG) modules. The aim is integrating TEG modules to cover the increasing demand of water in rural areas since rainy days in Sharjah are limited and the temperature is high. The performances of the proposed system will be demonstrated using Simulink simulations for the overall blocks of the proposed system.</p>

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