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Öğe A deep bidirectional recurrent neural network for identification of SARS-CoV-2 from viral genome sequences(AMER INST MATHEMATICAL SCIENCES-AIMS, PO BOX 2604, SPRINGFIELD, MO 65801-2604, 2021) Deif, Mohanad A.; Solyman, Ahmad Amin Ahmad; Kamarposhti, Mehrdad Ahmadi; Band, Shahab S.; Hammam, Rania E.In this work, Deep Bidirectional Recurrent Neural Networks (BRNNs) models were implemented based on both Long Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) cells in order to distinguish between genome sequence of SARS-CoV-2 and other Corona Virus strains such as SARS-CoV and MERS-CoV, Common Cold and other Acute Respiratory Infection (ARI) viruses. An investigation of the hyper-parameters including the optimizer type and the number of unit cells, was also performed to attain the best performance of the BRNN models. Results showed that the GRU BRNNs model was able to discriminate between SARS-CoV-2 and other classes of viruses with a higher overall classification accuracy of 96.8% as compared to that of the LSTM BRNNs model having a 95.8% overall classification accuracy. The best hyperparameters producing the highest performance for both models was obtained when applying the SGD optimizer and an optimum number of unit cells of 80 in both models. This study proved that the proposed GRU BRNN model has a better classification ability for SARS-CoV-2 thus providing an efficient tool to help in containing the disease and achieving better clinical decisions with high precision.Öğe The estimate of amplitude and phase of harmonics in power system using the extended kalman filter(Institute of Advanced Engineering and Science, 2021) Kamarposhti, Mehrdad Ahmadi; Solyman, Ahmed Amin AhmedNowadays, the amplitude of the harmonics in the power grid has increased unwittingly due to the increasing use of the nonlinear elements and power electronics. It has led to a significant reduction in power quality indicators. As a first step, the estimate of the amplitude, and the phase of the harmonics in the power grid are essential to resolve this problem. We use the Kalman filter to estimate the phase, and we use the minimal squared linear estimator to assess the amplitude. To test the aforementioned method, we use terminal test signals of the industrial charge consisting of the power converters and ignition coils. The results show that this algorithm has a high accuracy and estimation speed, and they confirm the proper performance in instantaneous tracking of the parameters. © 2021, Institute of Advanced Engineering and Science. All rights reserved.Öğe Increasing Power Transfer Capability of Transmission Lines Using the Quasi-Dynamic Operation and Monitoring System(International Information and Engineering Technology Association, 2022) Shokouhandeh, Hassan; Kamarposhti, Mehrdad Ahmadi; Lorenzini, Giulio; Solyman, Ahmed Amin Ahmed; Agieb, Ramy SaidOne of the key methods for reducing the possible interruptions and the pressures imposed on the operator is to employ the hidden capacity of the transmission lines. The basis of selecting the line capacity is the ability of the operator to preserve the allowed distance between the transmission line and the ground, trees, vehicles, and other obstacles that are directly under the line. One of the methods that increase the capacity of the employed line is the line monitoring equipment and using the dynamic capacity. Although the dynamic capacity method costs less than other options, it might be costly and laborsome. Thus, there should be a tradeoff between the dynamic and static capacity, known as the quasi-dynamic capacity. This term indicates that the dynamic capacity is used in studies for making logical decisions for changing the static capacity or operation of the operator. In many cases, this technology can be implemented temporarily and then removed or displaced for other applications. The purpose of this study is to present a quasi-dynamic method for determining and operating the line capacity to reduce the costs required to determine the complete dynamic capacity and improve the assumptions used in determining the static capacity. © 2022. Mathematical Modelling of Engineering Problems.All Rights ReservedÖğe Locating and sizing of capacitor banks and multiple DGs in distribution system to improve reliability indexes and reduce loss using ABC algorithm(Institute of Advanced Engineering and Science, 2021) Kamarposhti, Mehrdad Ahmadi; Khormandichali, Seyed Mohsen Mousavi; Solyman, Ahmed Amin AhmedDG sources have been introduced as one of the most widely used and effective methods among various methods providing losses reduction in power systems. In this paper, the artificial bee colony algorithm has been employed with the aim of determining location and capacity of distributed generations (DGs) and capacitor banks (CBs) in distribution systems. The proposed objective function includes power losses and ENS reliability index, which is used by deploying weight coefficients as objective function in the algorithms. Accordingly, the standard 37-bus networks have been used for studies. The simulation results demonstrate that the artificial bee colony algorithm is more effective in all sections and has higher capability in reducing losses and improving reliability as well. © 2021, Institute of Advanced Engineering and Science. All rights reserved.Öğe Locating and Sizing of Distributed Generation Sources and Parallel Capacitors Using Multiple Objective Particle Swarm Optimization Algorithm(International Information and Engineering Technology Association, 2021) Kamarposhti, Mehrdad Ahmadi; Lorenzini, Giulio; Solyman, Ahmed Amin AhmedIn this paper, the MOPSO algorithm has been used to locate and determine the capacity of distributed generation sources and capacitor banks in the distribution system. The intended objective function is a combination of different objective functions. The first goal is to reduce losses, and the second goal is to improve the voltage profile and the third goal is to reduce costs, which has been used by placing weight coefficients in the form of an objective function in the algorithms. For this purpose, the standard 33-bus system has been used to conduct studies. Studies have been repeated in three scenarios. In the first scenario, the locating and determination of the capacity of active and reactive resources has been accomplished with the approach of reducing losses and improving the voltage profile. However, in the second scenario, the locating and determining the capacity of these resources has been accomplished with loss and cost reduction approach and it was considered as constraint in voltage profile. In the third scenario, the simultaneous reduction of all three objective functions has been performed simultaneously. To validate the results obtained by the MOPSO algorithm, its results were compared with genetic and particle swarm algorithms. The results indicate better and more accurate performance of MOPSO algorithm in minimizing objective functions relative to other two algorithms. © 2021, Mathematical Modelling of Engineering Problems.All Rights Reserved.Öğe Maximum power point tracking in the photovoltaic module using incremental conductance algorithm with variable step length(International Information and Engineering Technology Association, 2021) Lorenzini, Giulio; Kamarposhti, Mehrdad Ahmadi; Solyman, Ahmed Amin AhmedTracking maximum power in photovoltaic applications is considered a major issue. Because of the change in the output power of solar cells by changing the radiation and temperature, it is required to receive the maximum power from solar array to be achieved the maximum efficiency using maximum power tracking methods. A large number of the maximum power methods have been introduced so far, but each has difficulty in terms of tracking speed and accuracy, and in practice, they have not been able to improve both of these factors. Among the commonly used methods, the incremental conductance method has a good tracking speed and accuracy, but at the same time, it cannot reach both to a desirable value. In this paper, a new method is proposed based on the above method that improves the mentioned factors simultaneously to an acceptable limit. The result of the simulation confirms the correctness of the claim of the proposed method. © 2021 Lavoisier. All rights reserved.Öğe Optimal Location of Sectionners and Distributed Generation Resources to Improve Reliability in Distribution Networks(International Information and Engineering Technology Association, 2021) Lorenzini, Giulio; Kamarposhti, Mehrdad Ahmadi; Solyman, Ahmed Amin AhmedIn traditional distribution networks, due to the radial structure and subscriber power supply, in the event of errors in the main feeders, downstream subscribers experienced a long blackout, which reduced the reliability level of the network. With the expansion of the use of scattered generations, storage resources and the use of load response methods, load retrieval is provided in the downstream area. In this paper, a method is proposed for locating sectionners and distributed generations in distribution networks with the aim of creating flexible micro-grids. By creating an island, disassembling and restoring loads of more importance in the distribution network, on the one hand, it reduces the amount of fines paid by the distribution company to Subscribers and economic interests of the distribution company, and, on the other hand, by improving reliability, provides customer satisfaction. © 2021. All Rights Reserved.Öğe Optimal operation of micro-grids to reduce energy production costs and environmental pollution using ant colony optimization algorithm (ACO)(International Information and Engineering Technology Association, 2021) Lorenzini, Giulio; Kamarposhti, Mehrdad Ahmadi; Solyman, Ahmed Amin AhmedWith increasing demand for electric energy and requesting higher quality by subscribers, the electric power industry has moved towards using new technologies. Many modern societies seek to use the systems of new energy management in order to reduce environmental pollutants and operational costs in electrical energy systems. Therefore, exploiting various resources of renewable energies, micro-grids can be considered as a significant tool to attain these objectives. According to the subject, Ant Colony Optimization algorithm (ACO) is used in this paper to optimize one micro-grid sample in order to reduce the cost of generating power and to reduce environmental pollution to increase reliability. The recommended algorithm has been done in two scenarios and each in two sections. In the first scenario, energy management will be conducted for all distributed generation resources and in the second scenario it is assumed that wind and solar products, produce their maximum power and energy management are conducted for the reminder elements and the results are compared with other optimization algorithms. © 2021 Lavoisier. All rights reserved.Öğe Optimization of PID controller parameters for automatic generation control in two-area heating system using firefly algorithm(International Information and Engineering Technology Association, 2021) Lorenzini, Giulio; Kamarposhti, Mehrdad Ahmadi; Ahmed Solyman, Ahmed AminAutomatic generation control is a vital part of operating and controlling power systems providing adequate and reliable energy with proper quality. Load frequency control is important in large-scale power systems which usually include interconnected control areas, to keep the system frequency and transmit power among areas close to planed values. The mechanical power put into the generators is used to control the frequency of the output electrical power and maintain the transient power among the areas at the planed value. A well-designed power system must be capable of acting well against load changes and perturbations of the system, providing a high level of expected power quality while keeping the frequency in an acceptable range. The problem of automatic frequency setting and crossing power of tie line in power systems dates long back in the history. Various control strategies, often related to the intelligent algorithm applications have been used in the load frequency controller design in recent years. The proportional integral derivative controller has drawn much attention among different types of load frequency controllers. However, recently using intelligent algorithms in optimization problems has occupied a prominent place. In this paper, the firefly algorithm is used to design a PID controller for automatic generation control in a two-area heating power system. The results of this simulation show that the proposed method has achieved a better dynamic performance compared to the PID controller with a degree of freedom in this system. Finally, the dynamic response of the power system under step load changes is investigated by the proposed method and it has been observed that 2-DOF PID controller optimized with the proposed firefly is very effective and it has a good dynamic performance. © 2021 WITPress. All rights reserved.Öğe A voltage stability-based approach to determining the maximum size of wind farms in power systems(International Information and Engineering Technology Association, 2021) Lorenzini, Giulio; Kamarposhti, Mehrdad Ahmadi; Ahmed Solyman, Ahmed AminCurrent methods to determine the wind farms maximum size do not consider the effect of new wind generation on the Voltage Stability Margins (VSMs). Installing wind power in one area may affect VSMs in other areas of the power system. Buses with high VSMs before wind power injection may be converted into weak buses after wind power injections in other parts of power systems, which may lead to limited future wind farms expansion in other areas. In this paper, two methods are proposed to determine two new wind farms maximum size in order to maximize wind power penetration level. In both methods, the size of any new wind farm is determined using an iterative process which is increased by a constant value. Proposed methods were used in the IEEE 14-bus power system. The results of applying these new methods indicate that the second method results in higher maximum sizes than the first method. © 2021 WITPress. All rights reserved.