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This article presents an innovative asymmetric multilevel inverter (MLI) topology that outperforms conventional counterparts. The introduced topology presents a breakthrough in implementing power electronics control by maximizing specific levels while minimizing switching components. A cutting-edge control scheme for optimal operation of the cascaded half-bridge MLI is presented. The ant lion optimization (ALO) algorithm was implemented to optimize the switching control to reduce the total harmonic distortion (THD) and improve power quality. For verification, the performance and effectiveness of the ALO technique are assessed by comparing its results to those obtained using the simplified sinusoidal pulse width modulation (SSPWM) technique, genetic algorithm (GA), and particle swarm optimization (PSO) in existing literature. Simulation results verified the efficacy of ALO in finding the optimal parameters. The suggested method showcases a remarkable reduction in the THD compared to SSPWM. The quality of the resulting waveform was enhanced, and both filter size and cost were significantly reduced. To meet stringent IEEE standards, an LC filter has been designed with minimal size and proper requirements. Experimental results validation of the suggested scheme, using a dSPACE R&D controller board unequivocally, confirmed its robustness and effectiveness. This groundbreaking study not only introduces a superior asymmetric MLI topology but also validates its exceptional performance through comprehensive analysis and experimentation. The experimental waveforms showed good matching with the simulation outcomes. The findings hold immense promise for advancing the field of power system control and revolutionizing the designing and implementation of efficient and cost-effective inverter systems.

The Multilevel inverter (MLI) plays a pivotal role in Renewable Energy (RE) systems by offering a cost-effective and highly efficient solution for converting DC from Photovoltaic (PV) sources into AC at high voltages. In addition, an innovative technology holds immense significance as it not only enables the seamless integration of PV systems into the grid but also ensures optimal power generation, thereby contributing to the widespread adoption of RE and fostering a sustainable future. This paper presents a modified sinusoidal pulse width modulation (SPWM) control scheme for a three-phase half-bridge cascaded MLI-powered PV sources. The selection of the MLI configuration is motivated by its reduced number of switching components, which enhances system reliability and simplifies experimental implementation. Compared to the SPWM schemes which require (m−1) carriers that make the generation of the pulse circuit very complex, the proposed control scheme requires only three signals: a carrier signal, a triangular waveform, and a modulating signal. This approach significantly reduces the complexity of control and facilitates practical implementation. The proposed control scheme simulation is verified using MATLAB/SIMULINK Software. The grey wolf optimization (GWO) algorithm is implemented to determine the optimal switching angles of the proposed control scheme. The Total Harmonic Distortion (THD) objective is selected to be the fitness function to be minimized for improving the quality of the output waveforms. For verification, the results of the proposed GWO-based modified SPWM control scheme are compared with those obtained using both the Particle swarm Optimization (PSO) and Genetic algorithm (GA) used in the literature. Simulation results declared that the proposed control scheme improves performance, especially THD which is minimized to 6.8%. Experimental validation has been conducted by building a laboratory prototype of the proposed system. The experimental and simulation results gave acceptable and limited convergent results considering the experimental difficulties.

This paper proposes a study on the potential of waste-to-energy (WTE) possibility in the Arab Republic of Egypt. WTE is a viable option for municipal solid waste (MSW) management and a renewable energy source. The issue of waste spread is a chronic environmental challenge in the Arab Republic of Egypt. The MSW practices in Egypt are simply done by collecting the waste and dumping it in open landfill sites. This research aims to assess the potential contribution of the WTE facility to meet electricity demand in Cairo City, which is Egypt’s capital and the biggest city in population as a sample, and then apply the results to all of Egypt. The paper introduced a step-by-step calculation for the electrical power that can be generated from Cairo MSW. Four scenarios for WTE utilization were developed: Mass Burn without any waste processing, Mass Burn with 25% recycling, Mass Burn excluding 50% of organic material, and Mass Burn excluding 50% of organic material with 25% recycling. The Mass Burn scenario implies full MSW stream incineration; the Mass Burn with recycling scenario considers a partial separation of reusable materials and the waste leftover for incineration; the Mass Burn with excluding 50% of organic material scenario considers a partial separation of organic materials and the waste leftover for incineration; the Mass Burn with excluding 50% of organic material with 25% recycling scenario considers a partial separation of organic materials and partial separation of reusable materials and the waste leftover for incineration. The analyses were done for the period 2011–2031 for Cairo with a total population of about 10 million in Nov 2021. The results show the huge potential of WTE conversion as a source of renewable energy, which is a key factor in Egypt’s sustainable development strategy 2030. Available data have been theoretically processed to show the decision-makers in Egypt the amount of electrical power that can be generated by using the WTE options to manage the MSW in Egypt.

In this paper, the operation and a complete design of the bootstrap circuit elements when firing a high-side MOSFET feeding an inductive load are introduced. The operation for both low-side and high-side cases are discussed with complete design and analysis of the bootstrap circuit elements. The effect of the bootstrap capacitor (BSC), diode, and resistance on the MOSFET switch for inductive loads at different frequencies and duty cycles including regular and SPWM are briefly analyzed. The current discontinuity is associated with higher losses, discontinued power output operation, and derated performance. The precise good design of the bootstrap circuit elements enables to improve the load current continuity in a specified frequency range of operation preventing the demerits of discontinuous operation. The effect of high-side implementation on extra harmonic content on the load is discussed including THD measurement of both applied voltages and currents.

The power system self-healing concept needs accurate and reliable fault detection, classification, and location (FDCL). This research proposes a novel and robust FDCL approach for distribution networks (DNs) in proportion to self-healing requirements. The proposed algorithm utilized a discrete wavelet transform (DWT) to decompose the measured current and zero sequence current component of only one terminal (substation) to detect and classify all fault types with the identification of the faulted phase (s). The fault location is achieved by integrating DWT and support vector machine (SVM). The data for training were extracted using DWT and collected, and then SVM was trained to locate the faulted section. The simplicity of the applied approach, ignoring DG’s data that is merged into the system, reduced training data and time, ability to diagnose all fault types, and high accuracy are the most significant contributions. The proposed techniques are tested on IEEE 33 bus DN with two distributed generation (DG) units, which are simulated in MATLAB. The simulation results demonstrate that the proposed methods give more accurate and reliable results for diagnosing the faults (FDCL) of various fault sorts, DN size, and resistance levels.

Medium voltage induction motors (MVIM) are a key component of numerous industries, such as water treatment plants, sewage discharge stations, and chilled water systems. The starting process for these MV motors is critical as it is associated with a major impact on both motor lifetime and power grid quality. In this article, a proposed modified and comprehensive starting scheme of MV three-phase induction motors driving pumps for water stations is introduced. Firstly, the starting performance and its impact on power grid quality will be discussed when all motors are normally started with direct on line connection (DOL), which is already the normal established status. A modified starting scheme based on an optimized coordination of motor starting methods in addition to variable voltage variable frequency drive (VVVFD) drive and control implementation will be discussed. A transition between the starting of variant MV induction motors as well as the starting event coordination principle will be discussed to improve the power quality relative to the obligatory time shift required for the operation. The coordination is based on an algorithm implementation which is achieved using different optimization concepts based on artificial intelligence techniques, properly conducting the transition time in addition to the power delivered by the inverter unit rather than determining the number of DOL and VVVF-implemented motors. A comparison between using the optimized VVVFD soft-starting and the proposed modified scheme is performed, focusing on the power quality improvement rather than optimizing the cost function. The modified scheme is simulated using ETAP power station for brief analysis and study of load flow rather than the complete inspection and power quality assessment.

The higher solar energy urges to maximize the solar energy extraction and utilization. This paper aim is to propose a new technique for extending the daily extraction time via a proposed aggregated PV cell. This system idea is using group of the photovoltaic (PV) cells to behave as an interactive regulated cell according to the series or parallel connections, it can call it an aggregated cell. This can be realized by interactive switching system according to the single cell output voltage. Six 6V PV cells are used for configuring the proposed single aggregated 6V PV cell. The technique depends on both single-cell number and their interconnections pattern. Switching the panel connection between the fully series cells to full parallel ones according to either sunlight states or the single-cell output is automatically achieved using an interactive control system. This system includes a voltage sensor that implements the suitable switching pattern for the aggregated cell. The ripple voltages during both morning and afternoon low sun times, as well as due to any other reason such as the lower clouds are efficiently eliminated. The simulated and the experimental results show in a satisfactory agreement the proposed aggregated PV cell validation.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide and the second cause of cancer related mortality. Treatment options for patients with metastatic CRC (mCRC) expanded during the last two decades, with introduction of new chemotherapeutic and targeted agents. Egypt is a lower middle-income country; Egyptian health care system is fragmented with wide diversity in drug availability and reimbursement policies across different health care providing facilities. We report the results of consensus recommendations for treatment of patients with metastatic colorectal cancer developed by Egyptian Foundation of Medical Sciences (EFMS), aiming to harmonize clinical practice through structured expert consensus-based recommendations consistent with the national status. EFMS recommendations could be utilized in other countries with similar economic status. EFMS recommendations were developed using a modified Delphi process, with three rounds of voting till the final recommendations were approved. A non-systematic review of literature was conducted before generating the provisional statements. Content experts were asked to vote on some recommendations in two different resource groups (restricted resources and non-restricted resources). External review board of experts from a low income and lower-middle countries voted on the applicability of EFMS recommendations in their countries. The current recommendations highlighted the discrepancy in health care between restricted and non-restricted resources with expected survival loss and quality of life deterioration. Access to targeted agents in first line is very limited in governmental institutions, and no access to agents approved for third line in patients who failed oxaliplatin and irinotecan containing regimens for patients treated in restricted resource settings. Management of mCRC in developing countries is a challenge. The currently available resource-stratified guidelines developed by international cancer societies represent a valuable decision-making tool, adaptation to national status in each country based on healthcare system status is required.

Background Less than 1% of all breast cancer cases are found in men, who reportedly have inferior outcomes compared with matched women patients. Ethnic differences may also affect their prognosis. Here, we investigated overall survival (OS) and major prognostic factors for male breast cancer (MBC) in a cohort of Egyptian patients. Methods We retrospectively analyzed OS in a cohort of 69 male patients with MBC who were surgically treated at the Mansoura Cancer Center, Egypt between 2000 and 2007. We registered demographic data, age, height, weight and body mass index, tumor size, histology, number of infiltrated axillary lymph nodes, hormone receptor (HR) status and metastatic presence, and TNM staging. Patients’ OS was the primary endpoint. Patients received treatment to the medical standards at the time of their diagnosis. Results In the 69 patients who met the inclusion criteria and had complete stored patient data, tumors ranged from T1c to T3. We could gather cancer-related survival data from only 56 patients. The collective 5-year survival in this cohort was 46.4%. Only five patients had distant metastasis at diagnosis, but they showed a null percent 5-year survival, whereas those with no lymph node infiltration showed a 100% 5-year survival. Lymph node status and tumor grading were the only prognostic factors that significantly affected OS. Conclusions Lymph node status and tumor grade are the most important prognostic factors for overall survival of MBC in Egyptian male patients; whereas even remarkably low HR expression in MBC did not significantly affect OS. Further research is needed to understand the factors that affect this disease.