Partially impaired antenna array is one of the challenges for estimating the accurate directions of the signals impinging upon antenna arrays. It causes random loss of the signal information, resulting in the poor direction of arrival (DOA) estimation performance. In this paper, we propose an efficient DOA estimation method under partially impaired antenna array elements, which work randomly. We first devise a strategy to detect the positions of randomly lost signal information corresponding to partially impaired antenna array elements and then formulate the problem of received signal recovery as low rank matrix completion. Afterwards, we utilize the recursive least squares (RLS) with the nulling antenna array for DOA estimation due to its fast convergence and low mean square error properties and place the nulls in the directions of received signals by adjusting the weight vectors adaptively. The reciprocal of the …

Internet of Things (IoT) has been widely used in recent years to solve a specific problem or perform an advanced function. In this paper, the IoT is used to build a distributed large-scale smart irrigation system that also aims to improve the load profile and the power quality of the system. Smart irrigation panels with built-in fuzzy logic control and integrated sensors have been designed and placed in a distributed manner along the system to provide the needed information about Persian conditions. The temperature, humidity, and soil resistivity sensors are used to provide the primary information for the irrigation and combined with current and voltage sensors for load demand and power quality purposes. The proposed IoT system is used for 47 bus power system. The first 31 buses are residential load bus with rating values of 50KVA. The other remaining 16 buses are used for agriculture purposes where a 30 hp water pump is connected in each bus area to supply water to the Persians. The test system is studied for different operation scenarios to allows study of the load demand, steady-state under-voltage, and sag transients. The proposed IoT system is compared with conventional under-voltage and sag solutions techniques. It shows a higher ability to manipulate the load profile and prevent under-voltage and sag existence when the conventional method fails for different irrigation operation conditions.

The PV panels' orientation significantly affects
their ability to produce electricity. The PV panels are typically
oriented in Egypt with an azimuth angle of zero degrees, directly
facing south, and a tilt angle corresponding to the latitude of the
installation location. In this research, the optimal orientation
and placement of PV panels, which are used for electric vehicle
(EV) charging station at Assiut university is studied. A
mathematical model is used to obtain the best tilt and azimuth
angles for the PV panels. Moreover, the optimal spacing
between the PV panels rows which is achieving minimal effect
of shading is determined based on the maximum harvested
energy and number of panels. The outcomes reveal that the
optimal value for the tilt and the azimuth angles are 22° and 27°,
respectively. At these optimal tilt and azimuth angles, the annual
harvested energy increases by 2.5% when compared with the
typical orientation of PV panels in Egypt. Furthermore, the total
output energy is enhanced by 24.9% at the optimal horizontal
spacing between the panels.

Power quality remains one of the most important
aspects of the operation of electrical distribution systems. Starting
of induction motors causes a voltage sag which negatively affects
the power quality. In the present research, the effect of
simultaneous energization of water pumping motors on the
operation of Karot distribution line is studied. Transient analysis
of induction motors during their acceleration period is pursued
using ETAP package. The obtained results indicate that the line
experience a 20% voltage sag for 7 seconds on simultaneous
energization of 16 motors from the line with a subsequent power
outage. Management of motors’ operation to avoid their
simultaneous acceleration is aimed at improving the power quality
of the line. Cascaded operation of the motors results in eliminating
the voltage sag problem where the line voltage never drops below
0.95 pu due to motors’ acceleration.

The magnetic flotation hybrid separation process, which combines column flotation and magnetic separation, was anticipated to beneficiate a representative coal sample acquired from the El-Maghara coal mine with a relatively high ash percentage of 27.21%. The system was designed to introduce a high gradient magnetic field to a flotation column to hinder the flotation of magnetic particles even if attached to flotation bubbles, improving the coal demineralization process and producing high quality coal. The Box-Behnken design and response surface methodology were employed to investigate and optimize the combined influence of various operating parameters on the process performance. The effects of the main operating parameters such as magnetic field strength, slurry circulation flow rate, air flow rate, collector dosage, and frother concentration were investigated. Ash percentage, combustible recovery, and separation efficiency were defined as process responses. Upgrading the coal sample under the optimum conditions of 1.2 T magnetic field strength, 1500 ml/min circulation flow rate, 11.64 ml/min air flow rate, 0.87 kg/ton diesel collector, and 42 ppm methyl isobutyl carbinol frother, the predicted and two confirmation experiments data were 7.78%, 7.89%, 7.71% ash percentages with maximum recoveries of 75.86%, 76.37%, 75.94%, and maximum separation efficiencies of 77.17%, 78.51%, 78.71% respectively.

To extensively explore the advantage of using nanobubbles in the ElMaghara coal flotation process, the effect of nanobubbles on both column and mechanical flotation was investigated under different operating parameters such as diesel oil collector dosage, MIBC frother concentration, superficial feed velocity, superficial air velocity, and superficial wash water velocity in column flotation; besides the slurry flow rate through nanobubbles generator into a 25-liter mechanical flotation cell. The representative coal flotation feed acquired from the El-Maghara deposit located in Sinai, Egypt with chemical characterization using proximate analysis containing 25.27% mineral matter forming ash during coal combustion and with particle size distribution measurement using laser particle size analyzer is 57 µm d90. Also, the flotation kinetic experiments were done to show the influence of nanobubbles on the flotation time required to obtain high-quality coal products with high combustible recovery. Nanobubbles enhanced the flotation performance and kinetics by up to 24% combustible recovery based on the operation parameters reducing flotation time from 4 to 2.25 min for 80% combustible recovery.

Millimeter wave (mmWave) massive MIMO systems will be used extensively in future communications systems to provide high data rates. For such systems, hybrid precoders are preferred to fully digital precoders in decreasing the cost and energy consumption. In this paper, we propose a partially connected hybrid precoding design on the orthogonal matching pursuit (OMP) algorithm. The proposed algorithm accounts for the limitations of analog beamforming circuitry and assumes channel state information (CSI) at both the base and mobile stations. Simulation results show that the proposed algorithm is superior to other solutions in the literature including the nearest Kronecker product (NKP) algorithm and successive interference cancellation (SIC) method. The proposed algorithm provides a higher data rate compared to other methods. In addition, the proposed design offers higher energy efficiency than the fully …

The topic of water management and distribution is addressed in this study with an IoTs (Internet of Things)-based solution. In typical systems, water distribution and consumption are not seen instantaneously, which slows the process of finding leaks desirable. An actual prototype that abstracts the Water Distribution Network (WDN) is created. To measure the desired physical quantities, namely, water flow rates, pH, and turbidity, sensors are mounted on the WDN. Hence, a network is installed to transmit the signal data to the Firebase platform. In this regard, a comprehensive IoT testbed design is developed to connect all the IoT devices. To grasp the leakage situation and control the water quality, actuators are fitted on the piping system in specified locations to cover the entire pipe network. Leakage and low water quality scenarios are conducted to test the capability of the developed prototype. The results show that …