The thermal performance of three solar collectors with 3, 6 mm and without perforation absorber plate was assessed experimentally. The experimental tests were implemented in Baghdad during the January and February 2017. Five values of airflow rates range between 0.01 – 0.1 m³/s were used through the test with a constant airflow rate during the test day. The variation of the following parameters air temperature difference, useful energy, absorber plate temperature, and collector efficiency was recorded every 15 minutes. The experimental data reports that the increases  the number of absorber plate perforations with a small diameter is more efficient rather than increasing the hole diameter of the absorber plate with decr

   In this paper, we investigate the basic characteristics of "magnetron sputtering plasma" using the target V₂O₅. The "magnetron sputtering plasma" is produced using "radio frequency (RF)" power supply and Argon gas. The intensity of the light emission from atoms and radicals in the plasma measured by using "optical emission spectrophotometer", and the appeared peaks in all patterns match the standard lines from NIST database and employed are to estimate the plasma parameters, of computes electron temperature and the electrons density. The characteristics of V₂O₅ sputtering plasma at multiple discharge provisos are studied at the "radio frequency" (RF) power ranging from 75 - 150 Wat

Massive multiple-input multiple-output (MaMi) systems have attracted much research attention during the last few years. This is because MaMi systems are able to achieve a remarkable improvement in data rate and thus meet the immensely ongoing traffic demands required by the future wireless networks. To date, the downlink training sequence (DTS) for the frequency division duplex (FDD) MaMi communications systems have been designed based on the idealistic assumption of white noise environments. However, it is essential and more practical to consider the colored noise environments when designing an efficient DTS for channel estimation. To this end, this paper proposes a new DTS design by exploring the joint use of spatial channel and n

This paper proposed a new approach for an underwater visible light communication (UVLC) system using MIMO (2Tx/2Rx) technology. The BER performance, Q-factor, and data rate of the UVLC system are looked at in coastal waters of the Jerov type (J1C, J3C, J5C, J7C, and J9C). The applied system takes into account the angles ranging from 0 to 15° and 45°. The results indicated that 32-PPM outperformed other modulation techniques.