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This manuscript presents the design of a low phase noise, high figure of merit (FoM) single-ended octagonal ring oscillator (RO). The proposed RO employs the pulse injection (PI) technique for performance enhancement. The PI technique is used for suppression of phase noise and spurious harmonics. Besides, a novel voltage dependent phase shifter is employed. The proposed RO has an output signal with voltage controlled phase. Different output signal phases can be obtained employing different selected voltages to control the output signal phase.The proposed injection locked ring oscillator (ILRO) represents a suitable implementation for phase shift keying (PSK). The proposed ILRO has a measured oscillation frequency of 4.9 GHz with a fine tuning range of 500 MHz. It has a measured phase noise of-126.17 dBc/Hz @ 1MHz offset while consuming only 4.8 mW of DC power. The proposed ILRO has a FoM of -193.17 dBc/Hz. This RO has been designed and implemented in 0.18 μm CMOS technology.

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Spillways usually used for escaping water from the U.S. having a high-water level, to D.S. having a low water level in most of the diversion head structures through water streams. The D.S. of such spillways usually suffers from the destructive impacts of the generated kinetic energy of the flowing water, having a very high speed, which may cause cavitation in such spillways body. In the present work, some geometrical treatments on the back of the spillway body, are introduced for increasing its efficiency in dissipating the kinetic energy of the flowing water, having great potential energy, and improving the flowing water quality by increasing its dissolved oxygen content, through generating huge aeration at the flow in the back, in addition to prevent cavitation which may occur, and generated on the back of the spillway body. Previous studies proved that the stepped back of the spillway body is one of the most practicable trails done for achieving the above-mentioned goals. In this paper, a review of previous authors` technical methods to obtain the best design of the spillway geometric that dissipates high values of the kinetic energy and improving the flow aeration.is highlighted.

Spillways usually used for escaping water from the U.S. having a high-water level, to D.S. having a low water level in most of the diversion head structures through water streams. The D.S. of such spillways usually suffers from the destructive impacts of the generated kinetic energy of the flowing water, having a very high speed, which may cause cavitation in such spillways body. In the present work, some geometrical treatments on the back of the spillway body, are introduced for increasing its efficiency in dissipating the kinetic energy of the flowing water, having great potential energy, and improving the flowing water quality by increasing its dissolved oxygen content, through generating huge aeration at the flow in the back, in addition to prevent cavitation which may occur, and generated on the back of the spillway body. Previous studies proved that the stepped back of the spillway body is one of the most practicable trails done for achieving the above-mentioned goals. In this paper, a review of previous authors` technical methods to obtain the best design of the spillway geometric that dissipates high values of the kinetic energy and improving the flow aeration.is highlighted.

Spillways usually used for escaping water from the U.S. having a high-water level, to D.S. having a low water level in most of the diversion head structures through water streams. The D.S. of such spillways usually suffers from the destructive impacts of the generated kinetic energy of the flowing water, having a very high speed, which may cause cavitation in such spillways body. In the present work, some geometrical treatments on the back of the spillway body, are introduced for increasing its efficiency in dissipating the kinetic energy of the flowing water, having great potential energy, and improving the flowing water quality by increasing its dissolved oxygen content, through generating huge aeration at the flow in the back, in addition to prevent cavitation which may occur, and generated on the back of the spillway body. Previous studies proved that the stepped back of the spillway body is one of the most practicable trails done for achieving the above-mentioned goals. In this paper, a review of previous authors` technical methods to obtain the best design of the spillway geometric that dissipates high values of the kinetic energy and improving the flow aeration.is highlighted.

Passive cooling of a photovoltaic module via fins attached to the rear surface of the module is investigated. A solar module with no air cooling was used as a base model for comparison against modules cooled by the attached fins, which serve as a heat sink. The modules with fins are cooled by still air and ventilation air. A theoretical study of heat transfer through PV modules with and without fins was conducted to investigate how the calculated cell temperature and module output power are influenced by the ambient temperature and solar irradiation. The results showed a drop of module temperature and increase of electrical efficiency due to fins cooling. The electrical efficiency of the module increases significantly with the increase of fins height and number. The calculated values of cell temperature, open-circuit voltage and short-circuit current of the module with and without fins agreed reasonably with those measured experimentally over the day hours. The output power over the day hours increases at first from sunrise until noon time followed by a decrease until sunset. On the contrary, the electrical efficiency decreases from sunrise until noon time followed by an increase until sunset in agreement with previous findings in the literature.