Solar cells are a major alternate source of sustainable energy in the usual condition of depleting non- renewable energy sources. Nowadays, this source is getting more and more important due to its use in large and small-scale installations. One of the major causes of energy losses in photovoltaic (PV) modules is the shading. It can happen due to clouds passing, near trees, and/or neighboring structures. Generally, there are two types of PV module Shading which are either partial shading or complete shading. Both have a significant impact on the solar module output power. This paper is an attempt of carrying out a study of the electrical characteristics of a solar module with various percentages of simulated shading. The solar module tester (SMT) simulator was used in this study. The study approved the direct correlation between short-circuit current and solar irradiance. The advantage of using SMT is its stable irradiance in comparison to the practical unstable solar irradiance within the same period. The results of both methods of shading simulation show that shading has a significant impact on the performance of solar panel in terms of efficiency, fill factor and output power. For better performance, solar panels should install in shading free places as much as its possible.

In this paper, a complete design and implementation of an automatic Multi-Axis solar tracking system has been introduced. The main purpose of this system is to track Sun location and gain the maximum energy output of the solar panels. The system is Multi-axis using microcontroller and photocells to control the direction of the penal, whereas the penal is facing the sun at all times of the day. The system is a combination of hardware and software parts that work concurrently to achieve a precise angular Sun tracking. A Base, Penal Frame, Super Jack Motors, high-efficiency Solar Panel, Arduino Uno microcontroller, Relays, Rechargeable battery, Light Dependent Resistor (LDR) have been used for the system’s hardware part. These hardware parts need a high-level programming code, as a software part, to be embedded in the microcontroller to get an effective and precise solar tracking system. The results of the presented system were compared to a fixed direction system. The results show significant efficiency improvement of 24% over the static one. For a city like Ramadi, which has a high irradiance all over the year, it is very fruitful to use such tracking systems along with photovoltaic installation systems.<div align="center"> </div>

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The internet of things (IoT) is one of the most advanced technologies that have emerged in the last decade. In recent years, IoT has been used in many medical fields. With the emergence of the Coronavirus pandemic, some IoT technologies were employed to serve the health sector to make quick and accurate decisions to save people's lives. However, there are still many ideas and works not yet implemented that could be applied in many aspects to preserve people's lives. Therefore, it is necessary to collect works and ideas that depend on IoT to produce modern systems quickly to serve the health sector. In this paper, a review of the most recent technologies of IoT against Coronavirus disease (COVID-19) has been done. A comparative and analysis among the previous works have been done to reach the most efficient depending on comparing the services that each work has provided. Besides that, suggest several new ideas that can be adopted as systems use IoT technologies and the expected advantages that can be gain from applying these ideas. A framework for a proposed idea to build a comprehensive monitoring system based on IoT technologies on the patient and hospital sides and expected advantages of implementing the system has been done.

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