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In this paper, we investigate various stabilisation problems of a hybrid system of elasticity, consisting of a thin tape, which moves axially between two sets of rollers. We present a control solution, which works simultaneously, for three variants of the tape model. In particular, we design boundary feedback control laws via Lyapunov's second method. The resulting closed-loop system for the general case is then analysed, where we prove the existence and uniqueness of solution using the semigroup theory of linear operators; furthermore, we prove the exponential decay of the solution via a frequency domain theorem. The stabilisation of the two other special cases is derived implicitly from the general case proofs presented in the paper. Finally, the paper is concluded by presenting computer simulations to support the theoretical results. [ABSTRACT FROM AUTHOR]

In recent years, the growing demand for efficient and sustainable energy management has led to the development of innovative solutions for embedded systems. One such solution is the integration of hybrid nanogrid energy management systems into various applications. There are currently many energy management systems in different domains, such as buildings, electric vehicles, or even naval transport. However, an embedded nanogrid management system is subject to several constraints that are not sufficiently studied in the literature. Indeed, such a system often has a limited energy reserve and is isolated from any energy supply for a long time. This paper aims to provide a comprehensive overview of the current state of research, advancements, and challenges in the field of hybrid nanogrid energy management systems. Furthermore, it offers a comparative analysis between hybrid nanogrids and microgrids and the implications of their integration in embedded systems. This paper also discusses the key components, operation principles, optimization strategies, real-world implementations, challenges, and future prospects of hybrid nanogrid energy management systems. Moreover, it highlights the significance of such systems in enhancing energy efficiency, reducing carbon footprints, and ensuring reliable power supply. [ABSTRACT FROM AUTHOR]

Renewable energy sources are essential for mitigating the greenhouse effect and supplying energy to resource-scarce regions. However, their intermittent nature necessitates efficient storage solutions to enhance system efficiency and manage energy costs. This paper investigates renewable and clean storage systems, specifically examining the storage of electricity generated from renewable sources using hydropower plants and hydrogen, both of which are highly efficient and promising for future energy production and storage. The study utilizes extensive literature data to analyze the impact of various parameters on the cost per kWh of electricity production in hybrid renewable systems incorporating hydropower and hydrogen storage plants. Results indicate that these hybrid systems can store electricity efficiently and cost-effectively, with production costs ranging from 0.126 to 0.3 $/kWh for renewable-hydropower systems and 0.118 to 0.42 $/kWh for renewable-hydrogen systems, with expected cost reductions over the next decade due to technological advancements and increased market adoption. The novelty of this study lies in its comprehensive comparison of hybrid renewable systems integrating hydropower and hydrogen storage, providing detailed cost analysis and future projections. It identifies key parameters influencing the cost and efficiency of these systems, offering insights into optimizing storage solutions for renewable energy. Moreover, this research underscores the potential of hybrid systems to reduce dependency on fossil fuels, particularly during peak demand periods, and emphasizes the importance of seasonal and geographic considerations in selecting energy sources. The study highlights the importance of policy support and investment in hybrid renewable systems and calls for further research into optimizing these systems for different seasonal and geographic conditions. Overall, the integration of renewable energy sources with hydropower and hydrogen storage offers a promising pathway to a sustainable, economical, and resilient energy future. [ABSTRACT FROM AUTHOR]

The uniform stabilization of a coupled system arising in the active control of noise in a cavity with a flexible boundary (strings under thermal effects) is considered. Unlike most articles on this subject, which employ the scalar wave equation when analyzing the asymptotic behavior of structural acoustic models, in this paper, we consider classical equations in terms of flow velocity and pressure to describe the acoustic vibrations of the fluid which fills the cavity. This allows to consider, for example, more realistic boundary conditions to model the coupling on the interface between the acoustic chamber and the wall. The main result of this paper, concerning the exponential stability of the model, is established by means of the frequency domain method and the semigroup theory. This method can be adapted to other first‐order hyperbolic dissipative systems as well. [ABSTRACT FROM AUTHOR]

The AIMD algorithm, which underpins the Transmission Control Protocol (TCP) for transporting data packets in communication networks, is perhaps the most successful control algorithm ever deployed. Recently, its use has been extended beyond communication networks, and successful applications of the AIMD algorithm have been reported in transportation, energy, and mathematical biology. A very recent development in the use of AIMD is its application in solving large-scale optimisation and distributed control problems without the need for inter-agent communication. In this context, an interesting problem arises when multiple AIMD networks are coupled in some sense (usually through a nonlinearity). The purpose of this note is to prove that such systems in certain settings inherit the ergodic properties of individual AIMD networks. This result has important consequences for the convergence of the aforementioned optimisation algorithms. The arguments in the paper also correct conceptual and technical errors in Alam et al. (2020, The convergence of finite-averaging of AIMD for distributed heterogeneous resource allocations. arXiv:2001.08083 [math.OC].). [ABSTRACT FROM AUTHOR]

This paper presents a novel hybrid structural control solution designed for distillation systems that utilize a solar source alongside an electrical grid. The power conversion architecture incorporates a reversible bridge rectifier and a quadratic boost converter. The hybrid photovoltaic grid configuration offers several benefits, including source complementarity, enhanced dependability, and energy availability aligned with power requirements. Leveraging a photovoltaic source operating at maximum power facilitates energy conservation. On the control front, an adaptive technique based on a reference model is proposed. Fuzzy logic governs the quadratic boost converter, simplifying the management of its complex nonlinear nature. The control strategy aims to maximize solar power utilization, minimize harmonic components in the grid current, synthesize an adaptive controller, and achieve a near-unit power factor on the grid. The simulation results for a steady distillation system demonstrate promising findings. Despite variations in irradiation, load power, and grid drops, the system maintains a minimal bus voltage ripple, remaining close to the intended value. Optimization of the panel-generated power leads to improved PV source utilization and enhanced system efficiency. Furthermore, the combination with an electrical grid achieves a low rate of grid current distortion and a unitary power factor. [ABSTRACT FROM AUTHOR]

A dual-pontoon WEC-breakwater system is proposed to optimise space utilisation and reduce construction costs by integrating wave energy converters (WECs) with breakwaters. Previous parametric studies on the dimensions and layout of WECs have primarily used potential flow theories, often neglecting the viscous effects in wave–pontoon interactions. In this research, I employ a fully nonlinear viscous model, OpenFOAM®, to address these limitations. I examine multiple parameters, including the gap width between the pontoons, the draft, and the structure breadth, to assess their impact on the functional performance of this hybrid system. Furthermore, I discuss the accurate hydrodynamic performance of waves interacting with multiple floating structures and explore how various parameters influence the dual-pontoon WEC-breakwater integrated system's functionality. I discuss a novel analysis of the effective frequency bandwidth, considering both wave energy conversion efficiency and wave attenuation efficiency, to reflect the overall performance of the integrated system. This paper investigates wave–structure interactions and suggests optimisation strategies for the WEC-breakwater integrated system. [ABSTRACT FROM AUTHOR]

This paper presents a novel approach to optical communication systems by introducing a hybrid MGDM–FSO (Mode Group Diversity Multiplexing—Free Space Optical) system. The primary objective of this innovative system is to address the limitations of traditional communication systems, particularly in challenging environmental conditions. By combining the advantages of MGDM, which enhances transmission capacity in optical fibers, with the flexibility and high data rates offered by FSO technology, the hybrid MGDM–FSO system aims to overcome obstacles encountered during data transmission. In this study, we provide a detailed analysis of the proposed system's architecture and performance characteristics under various operating conditions. Specifically, we investigate both single-input single-output (SISO) and multiple-input multiple-output (MIMO) configurations of the MGDM–FSO system. Performance metrics such as received power levels, bit error rate (BER), and quality factor (Q-factor) are evaluated to assess the system's efficiency across different weather conditions. Numerical simulations are conducted to analyze the system's performance under a range of scenarios. Our findings indicate that under clear weather conditions, both SISO and MIMO configurations exhibit optimal performance, characterized by high Q-factor and low BER. However, as weather conditions deteriorate to heavy rain and heavy fog, the Q-factor of the received signal decreases, highlighting the impact of environmental factors on system performance. This study contributes valuable insights into the behavior of hybrid MGDM–FSO systems and emphasizes the importance of robust communication techniques to mitigate environmental challenges. The findings presented here have implications for the design and implementation of optical communication systems in real-world scenarios. [ABSTRACT FROM AUTHOR]

The use of renewable energy presents a viable alternative to fossil fuels. However, their intermittent nature does not allow for an immediate response to energy demand. Thus, it is necessary and beneficial to harness various renewable sources and integrate a storage system as an auxiliary source to mitigate this intermittency. The hybridization of energy sources requires efficient management of power flows to ensure the proper functioning of the overall system, regardless of changing weather conditions. In this paper, we propose an intelligent power management control for hybrid wind-solar-battery systems connected to micro-grids based on fuzzy logic. The proposed control approach addresses several specific challenges compared to conventional methods in the intelligent energy management of renewable hybrid systems. It effectively manages the uncertainties and nonlinearities inherent in weather variations, optimizes performance by dynamically adjusting the operations of energy sources and storage systems, and ensures efficient realtime utilization of available energy resources, thus providing greater flexibility and adaptability. Additionally, it enhances the stability and reliability of micro-grids by integrating more flexible and adaptive decision-making mechanisms. The simulation results using MatLab/Simulink demonstrate the significant advantage of this intelligent management lies in its ability to precisely control the state of charge of the battery across five distinct levels, which is not achievable using traditional management practices that rely solely on the maximum and minimum levels of the state of charge. [ABSTRACT FROM AUTHOR]

This paper presents the principles of developing an electromechanical emulator based on an original hybridization concept of a wind and tidal power system. Wind and tidal horizontal axis turbines showcase functional similarities and electromechanical coupling possibility. Tidal concepts are very close to those of wind power. Tidal turbine technology should thus reach maturity more quickly because it is possible for it to rely on a certain number of reliable and proven techniques developed for wind power. The proposed hybrid wind – tidal turbine system is electromechanically coupled on the axis of rotation of a single and common electric generator. An experimental simulation of the hybrid wind-tidal turbine system was carried out, using a developed architecture of an emulator system. The results are both numerical simulations carried out in the MATLAB/Simulink environment and tests obtained employing real-time emulators. [ABSTRACT FROM AUTHOR]

This paper presents a novel integration scheme of solar Photovoltaic (PV) with a large-capacity Doubly Excited Induction Generator (DFIG)-based wind energy system. The proposed scheme leverages both the grid and rotor-side power converters of the DFIG to inject PV power into the grid, eliminating the need for a dedicated converter for PV power processing and offering a cost-effective PV-grid integration solution. The system effectively delivers a substantial amount of PV power to the grid when compared to an equivalent rating inverter used in conventional PV-grid systems. Moreover, the proposed scheme prevents circulating power during sub-synchronous operation in the presence of solar radiation, enhancing overall system efficiency. Additionally, the system's stability benefits from turbine inertia, allowing for higher PV penetration into the power grid. The intermittent complementary nature of solar PV and wind energy sources significantly improves the utilization of the converters. Furthermore, the proposed scheme minimally impacts Maximum Power Point Tracking (MPPT) for PV and wind sources, except in rare environmental glitches, which the PV power control algorithm is adept at handling. The study provides a comprehensive system model used to design the control strategy, supported by analysis, simulations, and experiments conducted on a laboratory prototype. [ABSTRACT FROM AUTHOR]

Recent advancements in single-stage evaporative cooling (EC) have showcased their effectiveness as an energy-efficient and sustainable air-conditioning (AC) solution. However, several challenges hinder the widespread adoption of EC in various applications. These challenges include climate sensitivity, substantial spatial requirements, and limitations in achieving desired output temperatures. To address these concerns, there has been a growing focus on integrating EC with solar energy (SE) systems. With traditional energy resources being depleted, the use of SE has gained prominence as a sustainable solution to meet future energy demands while mitigating environmental pollution. This paper presents a comprehensive review of hybrid EC–SE systems, aiming to elucidate the potential synergies, benefits, and challenges associated with this integration. The review explores the principles and mathematical approaches of various configurations of EC systems to assess their compatibility with SE sources. Furthermore, the review delves into the mathematical model of SE, encompassing both solar power generation and thermal collectors, with the aim of integrating it into the EC model. It delves into key aspects of energy consumption and performance, showcasing advancements in achieving higher efficiency and enhanced cooling capacity through the hybrid systems. Additionally, the review highlights research gaps in the existing literature, emphasizing the need for further exploration in this interdisciplinary field. In conclusion, this paper offers valuable insights into the potential of EC–SE systems to address energy and cooling requirements while promoting sustainable development. [ABSTRACT FROM AUTHOR]

Introduction. This paper presents the novel design and analysis of a hybrid renewable energy system that combines a wave energy converter (WEC) with a floating photovoltaic (FPV) system for offshore installation, with a specific focus on Oran as a case study. The purpose of integrating these two technologies is to harness both wave and solar energy, thereby maximizing energy output and enhancing the reliability of renewable energy sources in offshore environments. The goal of this study is to develop a hybrid system that leverages the complementary nature of WEC and FPV technologies to maximize energy output and improve reliability. By integrating these technologies, the system aims to overcome the limitations of standalone energy systems. The methodology includes selecting suitable WEC and FPV technologies, optimizing their configurations, and analyzing their combined performance under various environmental conditions. To assess the energy production potential, structural stability, and economic feasibility of the hybrid system, computational simulations and data analysis are employed. This comprehensive approach ensures rigorous testing and optimization for real-world applications. The results demonstrate substantial improvements in energy yield and system resilience compared to standalone WEC or FPV systems. The hybrid system shows enhanced performance, particularly in consistent energy output and structural robustness. These findings indicate that combining WEC and FPV technologies can lead to more reliable and efficient offshore renewable energy solutions. The practical values are significant, providing insights into efficient and sustainable offshore renewable energy solutions. By focusing on Oran, it offers a localized perspective that can be adapted to similar coastal areas globally, contributing to the advancement of renewable energy technologies. The hybrid system’s enhanced reliability and efficiency support the broader goal of sustainable energy development in marine environments, highlighting its potential for widespread application and impact. [ABSTRACT FROM AUTHOR]

This paper addresses the optimal sizing of Hybrid Renewable Energy Systems (HRESs), encompassing wind, solar, and battery systems, with the aim of delivering reliable performance at a reasonable cost. The focus is on mitigating unscheduled outages on the national grid in Iraq. The proposed On–off-grid HRES method is implemented using MATLAB and relies on an iterative technique to achieve multi-objectives, balancing reliability and economic constraints. The optimal HRES configuration is determined by evaluating various scenarios related to energy flow management, electricity prices, and land cover effects. Consumer requirements regarding cost and reliability are factored into a 2D optimization process. A battery model is developed to capture the dynamic exchange of energy among different renewable sources, battery storage, and energy demands. A detailed case study across fifteen locations in Iraq, including water, desert, and urban areas, revealed that local wind speed significantly affects the feasibility and efficiency of the HRES. Locations with higher wind speeds, such as the Haditha lake region (payback period: 7.8 years), benefit more than urban areas (Haditha city: payback period: 12.4 years). This study also found that not utilizing the battery, particularly during periods of high electricity prices (e.g., 2015), significantly impacts the HRES performance. In the Haditha water area, for instance, this technique reduced the payback period from 20.1 to 7.8 years by reducing the frequency of charging and discharging cycles and subsequently mitigating the need for battery replacement. [ABSTRACT FROM AUTHOR]

With the increasing degrees AIs and machines, the need for implementing ethics in AIs is pressing. In this paper, we first survey current approaches to moral AIs and their inherent limitations. Then we propose the pluralist hybrid approach and show how these limitations of moral AIs can be partly alleviated by the pluralist hybrid approach. The core ethical decision-making capacity of an AI based on the pluralist hybrid approach consists of two systems. The first is a deterministic algorithm system that embraces different moral rules for making explicit moral decisions. The second is a machine learning system that accounts for calculating the value of the variables required by the application of moral principles. The pluralist hybrid system is better than the existing proposals as it better addresses the moral disagreement problem of the top-down approach by including distinct moral principles. Besides, the pluralist hybrid system reduces the opacity of ethical decision-making by implementing explicit moral principles for moral decision-making. [ABSTRACT FROM AUTHOR]

The incorporation of distributed generation with photovoltaic systems entails a drawback associated with intermittency in the generation capacity due to variations in the solar resource. In general, this aspect limits the level of penetration that this resource can have without producing an appreciable impact on the quality of the electrical supply. With the intention of reducing its intermittency, this paper presents the characterization of a methodology for maximizing grid-connected PV system operation under low-solar-radiation conditions. A new concept of a hybrid system based on a constant current source and capable of integrating different sources into a conventional grid-connected PV system is presented. Results of an experimental characterization of a low-voltage grid–PV system connection with a DC/DC converter for constant-current source application are shown in zero and non-zero radiation conditions. The results obtained demonstrate that the proposed integration method works efficiently without causing appreciable effects on the parameters that define the quality of the electrical supply. In this way, it is possible to efficiently incorporate another source of energy, taking advantage of the characteristics of the GCPVS without further interventions in the system. It is expected that this topology could help to integrate other generation and/or storage technologies into already existing PV systems, opening a wide field of research in the PV systems area. [ABSTRACT FROM AUTHOR]

Solar chimney power plants (SCPPs) are encouraging sustainable energy sources due to their low cost, abundance, low maintenance, and eco-friendliness. However, despite significant efforts to optimize SCPP design, their efficiency and power generation capabilities remain limited. Researchers have explored modifications in plant geometry and hybridization to improve efficiency. Despite extensive work in this area, commercialization of SCPPs has not yet been achieved. Most of the research is numerical and may differ from real-world practical use. The number of experimental studies is also relatively small. To facilitate commercialization, further investigation with practical and feasible dimensions is required. This comprehensive review paper aims to provide an in-depth analysis of experimental approaches and advancements in the field of SCPPs. The paper begins with an introduction, highlighting the background, significance, and objectives of the review. It provides an overview of the plants, discussing their principles and operation as innovative renewable energy systems. The historical development and evolution of solar chimneys are explored, shedding light on their progression over time. Case studies of operational hybrid SCPPs are examined to showcase real-world applications and performance. The paper also addresses environmental impacts and sustainability considerations associated with SCPPs. Furthermore, recommendations for future research and development in this field are provided to guide researchers and industry professionals. This study focuses on the possibility of commercialization of both standalone and hybrid SCPPs. [ABSTRACT FROM AUTHOR]

Sustainability has become a broad societal goal, aiming to ensure that human beings coexist safely and harmoniously with nature over a longer time. The influence of the COVID-19 pandemic on the global economy is coming to an end. The development and merits of sustainable energy supply, advanced technology, and economic features have received significant attention over the last few decades. However, significant gaps still exist with respect to how to design, construct, and implement hybrid and optimal energy systems with the lowest investment and cost. Since 2002, the Sustainable Development of Energy, Water, and Environment Systems (SDEWES) conferences have become a significant meeting venue for researchers to introduce, discuss, share, and disseminate novel concepts and ideas. This paper presents an overview of published articles in the Special Issues (SIs) dedicated by the series SDEWES conferences, especially those published in Energies recommended by the 16th SDEWES Conference, which was held on 10–15 October 2021 in Dubrovnik, Croatia. This SI in Energies focused on four main topics, including the application of renewable bioenergy, component enhancement in renewable systems, sustainable development for buildings and economic analysis and evaluation for sustainability. The collected papers provide insight into the topics related to recent advances in improving sustainable efficiency, including studies on waste-to-wealth techniques, utilization of hybrid bioenergy systems, heat exchangers and other components for performance enhancement, energy supply and demand analysis, low-temperature DHC systems, techno-economic assessment, and environmental evaluation. [ABSTRACT FROM AUTHOR]

This paper studies the influence of the weave parameter on the ballistic performance of multi-ply systems. Three types of plain weaves were put into investigation, namely, A090, A200, and A400. Tensile and yarn pull-out tests were performed to investigate the responses of fabric upon quasi-static loading. Penetration tests were performed to characterize the energy absorption capability of different multi-ply systems at impacting velocities ranging from 250 m/s to 460 m/s. It was found that the strength of the fabric sample increased almost linearly with fabric areal density, and the coarser weaves exhibited a greater resistance against yarn pull-out. The ballistic limit (V 50) of finer weave 13A9, is around than 42.5% higher than coarser weave 3A4. In terms of hybrid systems, placing finer fabrics in front and coarser fabrics in the rear exhibits higher ballistic limits than the reversed sequence (8–20 m/s differences), while placing coarser fabrics in front exhibited greater energy absorption capability when the impact velocity is sufficient to cause instant and localized failure. It was also found that the ballistic performance of the hybrid systems does not alter significantly with the mass percentage of the coarser weaves at high impact velocities (greater than 400 m/s). The results indicate that replacing the expensive ballistic weaves with cheap materials in a hybrid system is a reasonable alternative to achieve cost reduction without significant performance degradation. [ABSTRACT FROM AUTHOR]

This paper is concerned with reset controller design and $ \mathcal {L}_2 $ L 2 -gain stability of piecewise-affine systems under the framework of hybrid systems. Firstly, stability conditions of piecewise-affine systems under dynamic state-feedback control are established through bilinear matrix inequality conditions. Secondly, a reset controller with reset rules under the hybrid systems framework is proposed in the sense of Lyapunov and sufficient conditions for exponential and $ \mathcal {L}_2 $ L 2 -gain stability of the closed-loop systems are provided. Different from the piecewise-affine systems with the dynamic state-feedback controller, the reset controller is designed such that the $ \mathcal {L}_2 $ L 2 -gain performance of piecewise-affine systems can be enhanced. Thirdly, an LMI approach is proposed to avoid the difficulty of solving the bilinear matrix inequalities. Furthermore, robustness to inflations of the flow and jump sets is established, and robustness to the norm-bounded uncertainties is proposed. Finally, numerical simulations including a robot arm system, an inverted pendulum system and the Chua's circuit system are provided to illustrate the results. [ABSTRACT FROM AUTHOR]

Existing quantum hardware is limited in the number of bits and length of the series of operations. Nevertheless, by shifting parts of the computation on classical hardware, hybrid quantum-classical systems utilize quantum hardware for scaled-down machine learning approaches, which is quantum machine learning. Due to the theoretically possible computational speed-up of quantum computers compared to classical computers and the increasing volume and speed of data generated in earth observation, attempts are now being made to use quantum computers for satellite image processing. However, satellite imagery is too large and high dimensional, and transformations that reduce the dimensionality are necessary to fit the classical data in the limited input domain of quantum circuits. This paper presents and compares several dimensionality reduction techniques as part of hybrid quantum-classical systems to represent satellite images with up to 256 × 256 × 3 values with only 16 values. We evaluate the representations of two benchmark datasets with supervised classification by four different quantum circuit architectures. We demonstrate the potential use of quantum machine learning for satellite image classification and give a comprehensive overview of the impact of various satellite image representations on the performance of quantum classifiers. It shows that autoencoder models are best suited to create small-scale representations, outperforming commonly used methods such as principle component analysis. [ABSTRACT FROM AUTHOR]

The primary objectives behind transitioning from fossil fuels to green energy sources, with a particular focus on reducing both electricity costs and carbon emissions. This transition has prompted various sectors and sports bikes, to embrace renewable energy alternatives, with a specific emphasis on technologies such as photovoltaic systems, energy storage solutions, and power generation from machines. The core subject of investigation in this paper is the application of renewable energy sources within sports bikes, with a particular emphasis on a hybrid system. This hybrid system incorporates DC/DC, AC/DC, and DC/AC converters to meet the energy requirements of the facility. The central aim of the research is to identify the most economically efficient scale for a self-sufficient hybrid photovoltaic system that integrates stationary generators and battery storage. The research seeks to optimize the balance between cost-effectiveness and sustainable energy provision in the context of sports facilities. [ABSTRACT FROM AUTHOR]

Power generation from hybrid renewable energy systems is gaining popularity worldwide, especially in developing countries suffering from electricity crises. Small-scale hybrid wind and solar systems, especially in high-altitude agriculture regions, which may experience electricity shortages during extreme weather conditions, can be critical to achieving sustainability goals and objectives. The latter will be reached by providing clean energy and addressing economic concerns. Accordingly, the main aim of the current paper is to evaluate the techno-economic feasibility of a grid-connected hybrid (vertical axis wind turbine - 2-axis photovoltaic) system at high-altitude agriculture regions (Ardal and Faridan) in Iran for the production of clean energy. To this aim, the wind speed and solar radiation data were analyzed statistically using 13 distribution functions. The results indicate that Generalized Extreme Value produced the best fit for the wind speed and solar radiation data. Furthermore, the purpose of the current work is to evaluate the technical and economic aspects of grid-connected hybrid vertical axis wind turbines as well as PV tracking systems using RETScreen software. The results demonstrate that implementing the proposed system could generate significant amounts of electricity in order to meet the demand for domestic and agricultural applications while ensuring clean energy in line with sustainable development goals. Besides, this study can help integrate renewable energy into the grid and help policymakers facilitate the installation of rooftop small-scale hybrid systems in the future. [ABSTRACT FROM AUTHOR]

This paper explains how to operate a networked hybrid system. A Proton Exchange Membrane Fuel Cell (PEMFC) and a hybrid photovoltaic (PV) array system are taken into account. The hybrid system can run in Feeder Flow Control (FFC) or Unit Capacity Control (UPC) mode. Changes in load demand are adjusted by the main grid because the hybrid source's output is controlled by reference power in UPC mode. Renewable energy is widely used. When light and temperature fluctuate, a PV battery uses Maximum Power Point Tracking (MPPT) to give maximum power to a load. Photovoltaic electricity is uncontrollable because its output varies with the outside and cell temperature. PEMFC should be added to the hybrid system to overcome its limitations. The output of the hybrid source can be controlled by adjusting the output power of the frequency converter. As a result, it is necessary to set a reference value for the output of the hybrid source. In Feeder-Flow Control (FFC) mode, the feeder flow is controlled to remain constant, the hybrid source takes on additional load, and as a result, the feeder reference power needs to be understood. This method reduces load shedding and boosts electricity under high loads. Under light load, the hybrid power supply switches to UPC mode. When the load requirement is near the border of the mode change, UPC or FFC mode is used. Hysteresis eliminates power reference fluctuations. The proposed operation strategy increases system performance, system stability, and mode transitions by consistently operating the PV array at maximum output power and the Photovoltaic-Fuel Cell (PVFC) within its highefficiency range. [ABSTRACT FROM AUTHOR]

The great progress in information and communication technology has led to a huge increase in data available. Traditional systems can't keep up with this growth and can't handle this huge amount of data. Recommendation systems are one of the most important areas of research right now because they help people make decisions and find what they want among all this data. This study looked at the research trends published in Google Scholar within the period 2018-2022 related to recommending, reviewing, analysing, and comparing ebooks research papers. At first, the research papers were collected and classified based on the recommendation model used, the year of publication, and then they were compared in terms of techniques, datasets utilised, problems, contributions, and evaluation methods used. It was found that many in-depth studies of book recommendation systems directly affect how those systems grow. Many researchers interested in book recommendation systems can learn about the many parts of the field by looking at how the study was put together. [ABSTRACT FROM AUTHOR]

This paper conducts a comprehensive analysis of offshore wind-photovoltaic hybrid systems, presenting autonomous components tailored for maritime applications. Focusing on the critical role of these systems in supplying electricity to regions with limited infrastructure, particularly maritime zones, the study explores economic advantages over traditional power line installations, emphasizing remote areas. Key components, including battery storage, autonomy, battery selection (with a spotlight on lead-acid batteries), charge controllers, inverters, and the integration of Automatic Identification System (A.I.S.) for maritime safety, are discussed. The article concludes by underscoring the significance of power supply buoys for ship safety and efficient refueling near hybrid systems. [ABSTRACT FROM AUTHOR]

The paper considers the problem of short- and middle-term forecasting in the financial sphere. To solve this problem, a hybrid system of computational intelligence based on the group method of data handling (GMDH) and bagging, as well as an algorithm for its training, is proposed. The odd stacks of the hybrid system are formed by ensembles of parallel connected subsystems. ARIMA and the GMDH-neo-fuzzy hybrid network were chosen as such subsystems. The proposed system does not require a large training data set, automatically determines the number of stacks during training, and provides online operation. The experimental investigations were conducted using the proposed hybrid system, as well as separately using ARIMA and GMDH-neo-fuzzy. The accuracy of the predictions obtained is compared, based on which the feasibility of using the proposed hybrid system is substantiated. [ABSTRACT FROM AUTHOR]

This paper addresses a mode-dependent state-feedback H ∞ control for stochastic descriptor hybrid systems, considering both the absence and presence of actuator saturation. Firstly, the necessary and sufficient conditions for the stochastic admissibility criterion with H ∞ performance γ of the closed-loop system are proposed. Given the proposed non-convex condition, the author reformulates it into linear matrix inequalities (LMIs). Then, to extend the result to the systems with actuator saturation, the actuator-saturated control input is expressed as a linear combination of a given state-feedback control input and a virtual control input that always remains under the saturation level. To verify this expression, the set invariant condition is also suggested by using the singular mode-dependent Lyapunov function candidate. Therefore, the conditions for the existence of both the mode-dependent state-feedback H ∞ control and the ellipsoidal shape invariant sets are successfully derived in terms of LMIs. Two numerical examples demonstrate the effectiveness of the proposed method by solving optimization problems subject to the proposed LMIs that minimize H ∞ performance γ and maximize the invariant set, respectively. [ABSTRACT FROM AUTHOR]

A Distributed Control System is a concept of Network Control Systems whose applications range from industrial control systems to the control of large physical experiments such as the ALICE experiment at CERN. The design phase of the Distributed Control Systems implementation brings several challenges, such as predicting the throughput and response of the system in terms of data-flow. These parameters have a significant impact on the operation of the Distributed Control System, and it is necessary to consider them when determining the distribution of software/hardware resources within the system. This distribution is often determined experimentally, which may be a difficult, iterative process. This paper proposes a methodology for modeling Distributed Control Systems using a combination of Finite-State Automata and Petri nets, where the resulting model can be used to determine the system's throughput and response before its final implementation. The proposed methodology is demonstrated and verified on two scenarios concerning the respective areas of ALICE detector control system and mobile robotics, using the MATLAB/Simulink implementation of created models. The methodology makes it possible to validate various distributions of resources without the need for changes to the physical system, and therefore to determine the appropriate structure of the Distributed Control System. [ABSTRACT FROM AUTHOR]

This review paper provides a summary of methods in which artificial intelligence (AI) techniques have been applied in the management of variable renewable energy (VRE) systems, and an outlook to future directions of research in the field. The VRE types included are namely solar, wind and marine varieties. AI techniques, and particularly machine learning (ML), have gained traction as a result of data explosion, and offer a method for integration of multimodal data for more accurate forecasting in energy applications. The VRE management aspects in which AI techniques have been applied include optimized power generation forecasting and integration of VRE into power grids, including the aspects of demand forecasting, energy storage, system optimization, performance monitoring, and cost management. Future directions of research in the applications of AI for VRE management are proposed and discussed, including the issue of data availability, types and quality, in addition to explainable artificial intelligence (XAI), quantum artificial intelligence (QAI), coupling AI with the emerging digital twins technology, and natural language processing. [ABSTRACT FROM AUTHOR]

Telecommunication stations, particularly operating in rural areas, are usually powered by diesel generators due to the lack of access to the utility grid. However, the growing cost of energy due to the constantly increasing fuel prices and the related greenhouse gas emissions contributing to global warming have driven telecom companies to seek better energy management solutions. In this paper, we study the economic feasibility of an environmentally friendly power supply system for rural telecommunication station in the city of Skikda, northeast Algeria. The proposed system is a standalone hybrid PV–wind system with pre-existing diesel generators and battery storage. Different system configurations are considered in the study: (a) diesel generators only, (b) PV–diesel–battery, (c) wind–diesel–battery, (d) PV–wind–diesel–battery, and lastly (e) PV–wind–battery; this helps to select the optimal solution based on the lowest net present cost (NPC) and the cost of energy (COE) of each configuration. The optimization is performed using HOMER PRO software 3.14.2 version. The results showed that a hybrid system of 5 kW DG, 3.81 kW of PV capacity, three wind turbines, and a 14-battery bank is the best design for the proposed power system with an NPC of USD 85673 and a COE of USD 0.214. The greenhouse gas emissions were considerably reduced by more than half making the proposed system a technically, economically, and environmentally viable solution. [ABSTRACT FROM AUTHOR]