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The strength of water exchange capacity serves as a proxy for the self-purification capacity of water bodies, thereby playing a pivotal role in enhancing the overall water environment. This study focuses on the secondary outfitting area of the immersed tube tunnel within the Shenzhen–Zhongshan Link, utilizing either the substances transport model or the particle tracking model. This framework is designed to delve into the similarities, differences, and appropriateness of the Eulerian and Lagrangian methods in appraising the water exchange capacity of semi-closed water areas. The following key insights have been derived: (1) The spatial distribution patterns of water exchange capacity computed using both methods align, indicating a congruency in their fundamental principles. However, in our case study, the average water transit time determined by the Lagrangian method is 1.6 times higher than the average water residence time calculated by the Eulerian method, suggesting a more conservative approach by the Lagrangian method. (2) The results obtained from varying particle release times or initial concentration release times within a tidal cycle in the case exhibit notable disparities, highlighting the sensitivity of the system to these factors. (3) The Lagrangian method exhibits a significant 12% difference in average water transit time, compared to the mere 0.9% difference observed in the average water residence time calculated by the Eulerian method. This underscores the Lagrangian method's heightened sensitivity to the timing of particle release. Conversely, the Eulerian method offers more stable simulation outcomes in assessing the water exchange capacity of semi-closed water bodies, making it a preferred choice for such studies. However, if a comprehensive understanding of water exchange capacity, material transport trajectories, and final destinations is sought, the Lagrangian method would be the more appropriate approach. The research outcomes presented in this paper can serve as a valuable reference for selecting appropriate evaluation techniques for water exchange capacity in semi-closed water areas, encompassing not just immersed tube outfitting zones but also lagoons and harbor basins. [ABSTRACT FROM AUTHOR]

Free-burning arc discharges play important roles in physical processes such as cutting, welding, arc furnaces, and switchgear. Therefore, in this paper, a combination of node-based and edge-based finite-element methods with the finite-volume scheme is developed to investigate the dynamics of these arc discharges. Considering the significant effect of self-induced magnetic fields on the dynamics of the thermal plasma arcs, accurate analysis of these magnetic fields is essential, especially for 3D geometries describing realistic conditions. Accordingly, the edge-based finite-element module is utilized to study the Ampere law in its vector form for estimating the vector potential and the corresponding magnetic field. Furthermore, the current conservation equation is solved using the node-based finite-element technique. The fluid dynamics are also investigated with the well-known finite-volume method. This hybrid model gives more accurate magnetic fields and Lorentz forces. Electromagnetic forces create high-speed streams of thermal plasma and increase the pressure in the near regions of the electrodes. As a result, the pressure and velocity profiles are closer to the predicted results. In addition, the fluid flow changes the temperature distribution in a way that agrees with experimental measurements. [ABSTRACT FROM AUTHOR]

Depression is a prevalent mental disorder in contemporary society. Symbolic phase transfer entropy can quantify the dynamic interaction and information flow between electroencephalogram (EEG) signals in depressed patients and healthy groups, which can help diagnose and treat depression. However, the traditional symbolization process of symbolic phase transfer entropy adopts the basic template method, which makes the symbolic phase transfer entropy unable to express the characteristics and changes of time series in different time periods in detail. Therefore, this paper proposes an improved symbolic phase transfer entropy algorithm, which adopts the adaptive template method in the symbolization process of the symbolic phase transfer entropy algorithm so that it can capture the dynamic changes of time series more finely. It was verified on the task EEG signals of 40 depressed patients and 40 healthy people. The experimental results show that the improved symbolic phase transfer entropy can more accurately distinguish depressed patients from healthy people in lead F4 and lead O1, which is helpful for the study of the EEG pathological characteristics of depression. The improved symbolic phase transfer entropy algorithm makes up for the shortcomings of the traditional symbolic phase transfer entropy in capturing the dynamic changes of time series and provides help for the study of dynamic changes in complex systems. [ABSTRACT FROM AUTHOR]

This paper proposed a Legendre-based multi-element probabilistic collocation method for time-dependent stochastic differential equations, used for density estimation of unknown functions. This method involves discretizing the stochastic space, and on each element, constructing Lagrange interpolation basis functions based on Legendre–Gauss–Lobatto collocation/quadrature nodes. The proposed method is applied to approximate one-dimensional/two-dimensional smooth/non-smooth functions and is tested for accuracy in approximating random function values, density estimations, and mathematical expectations. This method is applied to stochastic nonlinear Schrödinger equations and coupled stochastic nonlinear Schrödinger equations, and all numerical results are compared with Monte Carlo simulation. [ABSTRACT FROM AUTHOR]

The increasing adoption of distributed generation (DG) systems, driven by their numerous advantages, has led to a growing utilization of hybrid systems. Multilevel converters have emerged as essential components in power electronics applications, offering benefits such as harmonic reduction. However, designing effective control strategies for multilevel inverters presents challenges. This paper proposes a multi-DG quasi-Z-Source Inverter (qZSI) designed with a cascaded H-bridge controller. The incorporation of qZSI in the system enhances reliability and component safety while enabling the implementation of additional shoot-through control. This feature facilitates the balancing of inequalities arising from the two DG sources, thereby improving disturbance rejection. Furthermore, a current control scheme is implemented on the AC side to seamlessly feed active power into the grid without introducing distortions in current injection. Overall, the proposed system addresses key challenges in multilevel inverter design and offers a promising solution for efficient and reliable grid integration of DG systems. This work is thus useful in variety of applications, including electric vehicles and environment sustainability. [ABSTRACT FROM AUTHOR]

Inversion of ionograms from vertical measurements is significant for studying the ionospheric structure and ionospheric wave propagation, and it has attracted widespread attention. The model method is a relatively common inversion method for vertical ionograms. In this paper, a model inversion algorithm based on the multivariate QP model (single quasi-parabolic ionospheric profile model) is proposed, which is different from the traditional QPS model (where the multiple quasi-parabolic segment ionospheric profile model uses quasi-parabolic or anti-parabolic models to represent E, valley, and F1 and F2 layers). In other words, the electron density height profile of each layer in the ionosphere is no longer described by a single QP model. Still, it is based on QP as the basic unit and characterized by a combination of multiple QP units, and the entire vertical ionospheric profile consists of a series of QP unit models. Moreover, in the case of the multivariate QP model, determining the parameters of each layer becomes more complex. This study provides a more straightforward method, which can determine the entire QP unit profile by selecting one of the three parameters of each unit QP. Based on this model, the inversion of vertical ionograms was achieved, and the effectiveness of the inversion algorithm was verified based on typical vertical ionogram data. [ABSTRACT FROM AUTHOR]

The giant magnetostrictive transducer is a transducer device that realizes magneto-mechanical energy conversion. Each mechanical component is connected by the joint surface to realize the transmission of ultrasonic vibration energy. To ensure the efficient transmission of energy, the influence of the contact characteristics of the joint surface on the output stability of the transducer is studied. According to the contact conditions between the mechanical joint surfaces of the giant magnetostrictive ultrasonic transducer (GMUT), the key factors affecting the mechanical vibration performance of the ultrasonic system are obtained by analyzing the vibration transmission characteristics of the joint surfaces. The influence of different joint surface contact characteristics (JSCT) on the amplitude–frequency curve of the transducer is analyzed by the ANSYS software. Simulations and experiments have been conducted to verify the predicted results. As the preload force increases, the natural frequency of the transducer increases, but the growth rate decreases. The natural frequency of the double-rod GMUT with a small joint surface area is slightly higher in the optimal output mode shape, while its amplitude is significantly larger. The optimal prestress for the GMUT with different-sized joint surfaces is 3–5 MPa. This paper acquires the JSCT under a high-frequency vibration condition, reveals the influence of the joint surface on the mechanical output performance of the GMUT, and can provide a theoretical basis for the design and analysis of the rotary ultrasonic vibration processing system. [ABSTRACT FROM AUTHOR]

When local discharge occurs inside the transformer, it will be accompanied by a burst sound to generate an ultrasonic signal, which can be used for fault monitoring and diagnosis inside the transformer. This paper focuses on studying the converter transformer and simulating and analyzing the location where local discharge is likely to occur in the converter transformer. The provided information includes the distribution of sound pressure within and outside the converter transformer and the impact of the winding on this distribution. Furthermore, the investigation focuses on the testing of local discharge in converter transformers using ultrasonic signals. A local discharge detection device for converter transformers has been developed. The experiment and analysis have been conducted, and what was learned was compared to the simulated outcomes. The determination of the local discharge position in converter transformers is based on the analysis of the time-varying waveform obtained at the observation point. This approach offers a novel method for finding and identifying local discharge. [ABSTRACT FROM AUTHOR]

Because the soft weak soil layer rich in confined groundwater is prone to local instability and failure in the construction of diaphragm wall trenches, in order to check the local slurry wall stability in the construction of diaphragm wall trenches, a new three-dimensional (3D) calculation method on the local stability safety factor (LSF) of slurry walls is proposed based on the minimum potential energy principle. After the new method is applied to two engineering cases, the value of the LSF solved is 0.82 for engineering case 1, and the values of the LSF solved are 0.84 and 1.05 when the phreatic water levels are 2 and 4.5 m, respectively, for engineering case 2. These results are very close to the calculation results in the existing references, so the rationality of the new method is verified. Then the sensitivity of the LSFs obtained from the new method to various parameters has been analyzed and clarified on the basis of ten design examples. Finally, the new method is used to check the local slurry wall stability in the construction of diaphragm wall trenches for a practical project, and the obtained values of the LSF for three concerned weak soil layers are 1.37, 1.19, and 0.82, respectively. These results are in agreement with the actual situation in the construction site. This reveals that both the 3D model established and the 3D calculation method proposed in this paper are suitable for application in practical projects. [ABSTRACT FROM AUTHOR]

In this paper, a winding loss calculation method used in the field of converter transformers is introduced into the realm of high-frequency transformers for the first time. In addition, the impact of winding structure on the calculation accuracy of the method is considered for the first time. Comparing the calculation results of this method with those of the formula method, based on the results of finite element simulation. The feasibility of using this method to calculate the winding loss of a high-frequency transformer is verified. First, the winding loss of rectangular wire commonly used in small-capacity high-frequency transformers is analyzed. Based on the finite element simulation results, the accuracy of the hybrid method is compared with the formula calculation method to demonstrate the feasibility of the hybrid method. Then, using the same method, the accuracy of the hybrid method in calculating the winding loss of the circular wire, which is also used in small-capacity high-frequency transformers, is compared with the formula method. The maximum number of continuous winding layers has been modified, and the outcomes for various layers are being computed. Finally, the cross-transposition winding structure is also calculated, demonstrating that the hybrid method is not only applicable to wires of various shapes but also compatible with different winding structures. The results show that the hybrid method has good calculation accuracy and applicability. It can provide more precise calculation results for the winding loss of high-frequency transformers with various winding shapes. [ABSTRACT FROM AUTHOR]

This paper establishes a data-driven Neural Network (NN) framework. The contact resistance of T2 copper blocks with different roughnesses is predicted by deep learning at room temperature and cyclic loading. The contact resistance problem can be regarded as a regression problem of mapping the high-dimensional array space of multiple variables to the contact resistance. This paper measures the contact resistance of copper blocks with different surface roughnesses under loading and unloading states and obtains the original dataset required by the algorithm. The data characteristics include three surface topography parameters, number of cyclic loads, loading and unloading conditions, and load magnitude, with the data labeled contact resistance. This paper compares the results of the NN model and Holm model results to verify the NN model's effectiveness. The comparison results show that the prediction results of the NN are consistent with the predictions of the Holm model. After training and debugging, the root mean square error of the multiple hidden layers neural network test set is 6.81%, showing a good prediction effect. In conclusion, the deep learning algorithm provides a new way for fast and accurate prediction of the relationship between T2 copper blocks and contact resistance under cyclic loading times and unloading states. [ABSTRACT FROM AUTHOR]

This paper aims to address the challenges of short optical communication distances and high Bit Error Rates (BERs) caused by seawater absorption, scattering, and underwater turbulence. This paper establishes an optical communication channel model based on the Monte Carlo method and simulates and analyzes the process of received optical power attenuation when light is transmitted underwater due to absorption and scattering. The simulation model focuses on the influence of seawater type, transmission distance, receiver position, and angle on the received optical power attenuation. The results of this simulation will provide theoretical support for the development of prototype underwater optical communication systems and experiments in complex environments. To solve the long-range weak signal reception and processing issues in underwater optical wireless communication systems, this paper proposes the design and implementation of an underwater optical wireless communication system using optimized on-off keying high-power light-emitting diode/laser diode modulation technology and avalanche photodiode (APD)/photomultiplier (PMT) receiver modules. In addition, this paper describes the design of the underwater optical communication host computer software, which provides functions such as mode selection, BER monitoring, and file transfer. To test the performance of the proposed system, this paper conducts experiments in a 35 m long pool, fixed platform, and underwater mobile platform, as well as cross-air-water interface optical communication performance test experiments in a complex hydrological environment. The results show that the system achieved a 35 m underwater medium communication distance, transmission rate of 5–20 Mbps, and cross-domain wireless optical communication function under the condition of a BER of less than 10−6. The experiments also revealed that the communication distance decreases as the turbidity of the water body increases and the PMT receiver module selected at the receiver end has a longer communication distance than the APD receiver module. Overall, this paper demonstrates the feasibility of the proposed technology for underwater optical communication systems in complex waters, providing theoretical and data support for the next engineering practice. [ABSTRACT FROM AUTHOR]

Short-term power load forecasting provides important guidance for the improvement of power marketing and control levels of power enterprises. In this paper, a novel method, named RF-TStacking, is proposed to forecast the short-term load. This study starts from the influence factors of the power load, the random forest is applied to estimate the importance of the influence factors of short-term load. Based on Stacking strategy, the integration of LightGBM and random forest is realized to achieve short-term power load forecasting. To improve the generalization ability of the load model, random put back sampling is used to sample each primary learner, and the average value is taken as the result of each primary learner. The Bayesian optimization is used to adjust the super parameters of the model to improve the accuracy of the selection of influencing factors. The load data of a region in northwest China are used for the testing, and it is found that the model can provide stable prediction results. [ABSTRACT FROM AUTHOR]

Charge trap is considered to be one of the effective characteristic parameters for qualitatively evaluating the aging status of insulating material. In this paper, the trap characteristics in oil-impregnated paper with different aging types (non-treatment, thermal treatment and electrical treatment) are investigated using a dual-level (shallow and deep energy) trap model based on space charge profiles and thermally stimulated depolarization current (TSDC) data. The simulated results based on the model are well consistent with the experimental results. On the other hand, the TSDC method can acquire much information related to the shallower traps, and the dual-level trap model can obtain much charge dynamics characteristics. It has been observed that thermally aging makes the shallow trap energy become deeper while electrically aging makes it shallower. Moreover, the trap density in oil-impregnated paper increases after aging regardless of thermal or electrical aging. [ABSTRACT FROM AUTHOR]

Compressive stress, a DC bias magnetic field, and an AC excitation field significantly affect hysteresis characteristics and magnetic energy losses of magnetostrictive materials. Therefore, studying high frequency magnetic losses of magnetostrictive materials under coupling of these three conditions is of great importance for improving the output performance of high power magnetostrictive transducers. In this paper, a magnetic property testing system for magnetostrictive materials has been constructed. It enables the magnetic property testing of Terfenol-D alloy rods under the simultaneous application of stress and DC bias at high frequency excitation (a maximum AC magnetic flux density of 0.5 T at an excitation frequency of 9 kHz). Based on Bertotti separation theory and experimental data, considering the coupling effect of stress and DC bias, a computational model for the high frequency magnetic losses of Terfenol-D materials is proposed. The model incorporates relevant parameters of stress and DC bias to modify loss coefficients, and the expressions for loss coefficients are identified using the symbolic regression method. A comparative analysis between experimental data and model calculation shows good agreement, with the maximum and average errors of 4.68% and 1.74%, respectively. [ABSTRACT FROM AUTHOR]

Multiple-gated junctionless transistors (JLTs) with an extremely simple structure and bulk-conduction-based operation could overcome fundamental problems with respect to short-channel effects for sub-3-nm technology nodes. In this paper, the performance of a tri-gate JLT with an electrostatically highly doped channel is demonstrated through numerical simulation. Unique characteristics previously reported in fabricated JLTs were exhibited by the tri-gate transistors with an additional bottom-gate bias (Vgb = 50 V), which induced an effectively highly doped state of the channel. The results of this study show the feasibility of producing impurity scattering-free JLTs for next-generation technology nodes. [ABSTRACT FROM AUTHOR]

Lenses are fundamental elements in many optical applications. However, various aberrations are inevitably present in lenses, which will affect the distribution of focused light intensity and optical imaging. Accurately predicting the aberrations of a lens is of great significance. Nevertheless, quantitatively measuring the aberrations of a lens, especially when multiple aberrations are present simultaneously, is a challenging task. In this paper, we propose a method based on a designed deep residual network called Y-ResNet to measure the astigmatism and coma of a lens simultaneously. The Y-ResNet was trained on the focused image pattern of a Gaussian beam passing through a lens with astigmatism and coma. The trained network can accurately predict the aberration coefficients of the lens with 0.99 specificity, 0.925 precision, 0.9382 recall, and a 0.9406 F1-score achieved on astigmatism and 0.99 specificity, 0.956 precision, 0.98 recall, and a 0.954 F1-score achieved on coma. Specifically, even if only part of the intensity distribution of the light spot is captured, the network can accurately estimate the aberrations of the lens with an accuracy of over 90% on coma and can identify astigmatism aberration features. This paper can provide a feasible method for correcting beam patterns caused by aberration based on deep learning. [ABSTRACT FROM AUTHOR]

We present here a computational numerical operator, and we name it as Time Invariance Operator (TIO). This operator can add obstacles to the domain of the differential equation that describes a physical phenomenon. After the TIO acts, the wave equation recognizes the introduced points as non-interacting zones without affecting the rest of the domain. Computational physics has been consolidated as an important field of study, especially when connected with the fundamentals of physics. In many cases, simulations are conducted considering the ideal case of a wave in an infinite domain and open space without considering obstacles, barriers, or other aspects of the real world. The results presented in this paper allow us to infer that the TIO is the easiest way to apply the physical domain to wave propagation simulations and successfully recreate wave interaction experiments through computer simulations. Our motivation is to perform wave simulations that interact with obstacles, barriers, single slits, and double slits. We aim to investigate the results obtained in images to determine if the methodology we used to introduce realistic physical characteristics was successful in presenting the expected phenomenology. The simplicity of the TIO's action in creating locally time-invariant regions over the domain makes it suitable not only for waves but also for equations with transient terms. Heat transfer, mass transfer, computational fluid dynamics, and other time evolution equations can take some benefit from the operator presented in this paper. The TIO ensures local conservation that mimics interaction regions or ensures free space characteristics if it is the case like a 2D tensor of local conservation. The principal result from this paper is the validation of the TIO to impose realistic conditions with minimal modifications over a running code of wave equation simulation originally in free space. The TIO is innovative because it imposes dynamic conditions that mimic realistic interacting zones. [ABSTRACT FROM AUTHOR]

Transcranial magnetic stimulation (TMS) is a noninvasive neuromodulation technique for treating various neurological disorders. The geometry of the TMS coil determines the focality, stimulation field strength, and stimulation depth of the induced electric field. In this paper, we introduce a novel coil, named the eccentric folding coil (EFC). We used Sim4Life, a three-dimensional human tissue medical electromagnetic simulation software, and the brain models of the subjects from the population head model repository to conduct finite element simulations of the eccentric folding coil, circular coil, and figure-eight coil, implying that the largest EFC has a focal area of 19.5 cm2 less than the smallest circular coil, and the EFC of any size has a smaller focal area than the figure-8 coil of the same size. Furthermore, we stimulated the model from three directions with the coil and measured the electric field responses of the model, confirming that stimulation varied in different directions. Additionally, we applied EFC to four representative human models and found that the electric field in different subjects' brains differed by 3.03 mm in stimulation depth and 12.9 cm2 in focal area, suggesting that personalized human head modeling and electromagnetic analysis are essential for TMS treatment. In the future, we will explore using different types of TMS devices for patients with different conditions to achieve more precise and customized treatment. [ABSTRACT FROM AUTHOR]

The two-dimensional distribution method based on the laser spectrum is widely used in the reconstruction of two-dimensional temperature fields or concentration fields. However, the existing methods are all based on small-scale measurements. In large-scale spatial detection of farmland, the detection accuracy cannot reach the expected result due to the long optical path and the noise of various frequencies brought by environmental factors such as vibration, temperature, and other interfering gases. Aiming at the above-mentioned problems, this paper proposes a method to reduce open optical path noise interference in two-dimensional gas detection of farmland to improve detection accuracy. The signal denoising approach combines variational modal decomposition with the SG filtering algorithm to decompose, smooth out, and rebuild the detection signal. In addition, we built a two-dimensional detection system based on an open optical path. Throughout experimental validation, the proposed method outperformed the traditional method by 24% and 19%, respectively, in terms of the fitting degree and fitting effect of the gas absorption curve. [ABSTRACT FROM AUTHOR]

This paper describes the origin, principles, practical applications, and future perspectives of mass-selected ion beams generated using two rotating electric-field mass (REF-MS) filters. Our team has been investigating the underlying principles of REF-MS separation and assessing the feasibility of developing suitable systems to realize mass separation and ion beam convergence using rotating electric fields as well as the practicability of this method. This paper focuses on the mechanism underlying the observed cycloid trajectories followed by REF-MS-selected ions. A focused ion beam column with Ga and AuGe liquid metal ion sources (LMISs) was connected to REF-MS optics to assess the mass-selection performance of the filter. The mass-separation ability of this system was demonstrated by the ion projection images of Ga-LMIS (69Ga+ and 71Ga+) and AuGe-LMIS (97Au2+, Au2Ge+, and Au2Ge2+). The column was then replaced with a vacuum electrospray ionization (ESI) source. The size-selected water-cluster ion beams [(H2O)nH]+ were separated based on cluster size, and a microscale crater was created. Co-containing molecular ion beams were revealed using different concentrations of ESI sources, and a mass-separated [Co(DEGBE)4]+ ion beam was constructed. [ABSTRACT FROM AUTHOR]

This paper presents an alternative optical characterization of biosensors based on supported lipid monolayers (SLMs). Developing these biosensors requires precise thickness characterization of the films to understand their structure and dynamics. This paper proposes an optical technique to measure the thickness, optical properties, and location of a dipalmitoyl-phosphatidylcholine (DPPC) SLM on top of a metallic thin film. DPPC SLMs are of interest for biosensing applications, such as detecting pulmonary-related infections like SARS-CoV-2, Avian Influenza, and the H1N1 influenza virus. The monolayer was fabricated using the Langmuir–Blodgett technique, and the experimental characterization consisted of measuring the surface-plasmon resonance angle in the Kretschmann configuration. This technique provides an alternative option for real-time visual inspection and determination of the location and shape of DPPC monolayers in large areas. Therefore, it offers a useful tool for further developing SLM-based biosensors. [ABSTRACT FROM AUTHOR]

Albert Einstein proposed a unification of mechanics and electrodynamics by his special theory of relativity, which describes point-like particles moving through empty space. We show in this paper that mechanics and electrodynamics can be unified in Euclidean space if we relax the idea of point-like particles by describing fermions and bosons as spatially extended wave objects. Based on the process theory of gases presented in Paper II [Kalies et al., AIP Adv. 13(5), 055317 (2023)] of this series, we consider a confined photon gas and show that the momentum work of photons leads to an analogous description of matter and light and to the insight that electromagnetic energy is momentum energy. We present the unified energy equations, which do justice to the wave nature of matter, and it is the momentum work that links physical theories. Without momentum energy, which is larger in real terms than the kinetic energy of mechanics, the theoretical edifice of modern physics, at the fundamental level, is incomplete. [ABSTRACT FROM AUTHOR]

In this paper, a biomimetic topology optimization design method that simulates the growth pattern of leaf veins is proposed for the design of the support structure of ultra-light airfoil-like solar cells in the solar powered unmanned aerial vehicle. This method simulates the optimal growth process of main vein morphology through the topology change of dynamic point groups to obtain an optimized topological main support structure and then generates a Voronoi grid structure in the area surrounded by the main support structure to increase the local support for the battery. The whole process is combined with genetic algorithm to simulate the optimal distribution strategy of leaf vein growth by inputting a small number of parameters. Compared with the traditional grid support structure, the support structure obtained by simulating the leaf vein growth optimization strategy can provide more efficient support for the solar panel and avoid damage to the solar cell. [ABSTRACT FROM AUTHOR]

With the increasing number of space debris and extreme working environment, the space station faces the risk of cabin damage. Once the leakage occurs, it must be repaired in time. Identifying the shape of leaks can guide for astronauts to make plugging plans. The current research on leak identification methods is mostly aimed at circular leaks with different diameters, and there is little research on leak identification with different shapes. Therefore, it is of great significance to research leak shape identification methods. A method for identifying the shape categories of vacuum leaks based on improved variational mode decomposition and support vector machine is proposed in this paper: first, using the improved algorithm to determine the uniform number of modes K and adaptively optimize the quadratic penalty coefficient α. Then, apply the variational mode decomposition to the leakage signal and calculate each mode's maximum frequency. Setting these frequencies as eigenvalues for training and testing the identification model is based on support vector machine. In the experiment, four shapes of the leaks were used: ellipse, rectangle, round, and square. The experiment proves that this proposed method has stable and high identification accuracy, and can realize the shapes categories identification for the leaks, which can provide an important basis for spacecraft in-orbit leakage maintenance. [ABSTRACT FROM AUTHOR]

Momentum work enables a complete shift from kinematics to dynamics. This involves changes in the very fundamentals of physics, not only in mechanics, statistical mechanics, and special relativity, as shown in Papers I–III [G. Kalies and D. D. Do, AIP Adv. 13(6), 065121 (2023); G. Kalies, D. D. Do, and S. Arnrich, AIP Adv. 13(5), 055317 (2023); and G. Kalies and D. D. Do, AIP Adv. (in press) (2023)] of this series, but also in thermodynamics. In this paper, we challenge the narrative that classical phenomenological thermodynamics is completed and show that it represents an efficient interim solution that hides essential information. The essence of heat transfer and entropy is revealed, and an answer is given to the question of why entropy had to remain abstract and elusive in the past. Furthermore, we uncover the specific forms of energy behind thermodynamic state variables, such as enthalpy, Helmholtz free energy, and Gibbs free energy, which play a central role in describing chemical reactions and phase transitions. We thereby lay the foundation for thermodynamics to evolve from a framework theory valid for macroscopic systems to vivid quantum-process thermodynamics. [ABSTRACT FROM AUTHOR]

This paper analyzes an accident of abnormal increase of pole bus differential current and pole differential current of a converter station caused by line fault of a ±800 kV extra high-voltage direct current transmission project. After a lightning strike caused a short circuit and grounding of the DC line, the sudden voltage change protection of the DC line was triggered and the DC full voltage restart was successful. The pole bus differential current and pole differential current of the converter station have reached the protection set but have not reached the protection delay set; therefore, the differential protection has not acted. This paper first introduces the configuration principles of pole differential protection, pole bus differential protection, and line voltage sudden change protection for extra-high voltage converter stations. Second, the operation of the DC protection under this fault was analyzed in detail, and the reasons for the occurrence of pole bus differential current and pole differential current were also analyzed in this paper. Then, the range of equipment that caused the abnormal increase in differential current was identified. Finally, the lightning strike model was built on the real-time digital system, and the fault was simulated and replicated. It was determined that the abnormal increase in differential current was caused by the discharge of the pole bus surge arrester caused by the second lightning strike on the DC line. [ABSTRACT FROM AUTHOR]

This article aims to introduce the inverse new XLindley distribution, a further extension of the new XLindley distribution. The article explores various properties of the proposed model, such as the quantile function, stochastic orders, entropies, fuzzy reliability, moments, and stress–strength estimation. The paper also compares different methods of estimating the parameters of the proposed model and evaluates their performance using a simulation study. Moreover, the paper demonstrates the usefulness of the proposed model by applying it to two real datasets. The article shows that the proposed model fits the data better than seven existing models based on model selection criteria, goodness-of-fit test statistics, and graphical visualizations. The paper concludes that the new model can be a valuable tool for modeling and analyzing hazard functions or survival data in various fields and contributing to probability theory and statistical inferences. [ABSTRACT FROM AUTHOR]

In response to the green development strategies of countries all over the world, research on degradable epoxy resins has attracted widespread attention. The introduction of reversible covalent bonds in the conventional cross-linked structure of epoxy resins is one of the methods to achieve degradation of epoxy resins, and most researchers use molecular dynamics simulations in their preliminary studies to investigate the feasibility of the introduction of reversible covalent bonding schemes. The purpose of this paper is to investigate the feasibility of introducing C=N into the cross-linked structure of epoxy resins. Four formulation schemes of vanillin-based monoepoxides with the curing agent 4,4′-methylenebis(cyclohexylamine) were designed, and the molecular dynamics simulation method was used to cross-link them. The changes in the cross-linking degree, structural parameters before and after cross-linking, free volume fraction, and C=N content before and after cross-linking were investigated. The effects of different C=N contents on the thermal properties such as glass transition temperature and thermal expansion coefficient, as well as the mechanical properties such as the elastic modulus and shear modulus of this epoxy resin, were investigated. The bond-breaking characteristics of C=N, C–N, and C–O were compared by density of states and differential charge density simulations. Then the degradation mechanism of epoxy resin after the introduction of C=N was illustrated. The results show that as the specific gravity of the curing agent molecule increases, the cross-linking degree tends to increase. The cross-linked model has reduced volume, increased density, decreased energy, and a more stable structure. After crosslinking, the gaps between the segments in the system become smaller, and the fraction of free volume decreases as the proportion of crosslinking agent molecules increases. The C=N content in epoxy resin shows an increasing trend first and then decreases with the increase in the proportion of the curing agent. The glass transition temperature of the material increases with the increase in C=N content, while the coefficient of thermal expansion decreases with the increase in C=N content. The elastic modulus and shear modulus of the material show an increasing trend with the increase in C=N content, with a relatively gradual change in magnitude. Compared with C–N and C–O bonds, the C=N bond is weaker in strength, has a greater polarity, and is more prone to cleavage and degradation. [ABSTRACT FROM AUTHOR]

Traditional tethered nerve implants have many limitations since they rely on physical wires for power and signal transmission. Wireless stimulation technology can promote the exploration of neurological diseases and meet patient requirements, stemming from its portability and efficiency. In this paper, the link transmission characteristics of a sub-millimeter inductor are investigated by simulation, electrical tests, and theoretical analysis. The inductor acts as the receiving coil of a wireless stimulation device, and the wireless energy transmission process based on magnetic induction coupling is analyzed. Second, a novel millimeter-scale wireless stimulator device for neuromodulation is designed based on the parameters of transmitting and receiving coils obtained from the simulation. Finally, rat electrophysiological experiments are conducted to assess the feasibility of the device. The field Excitatory Post Synaptic Potential baseline is first recorded in the CA1 radiation area for 10 min, followed by the addition of high-frequency stimulation, and after successful induction of long-term potentiation (LTP) and recording for 10 min, the two coils are fixed at a distance of 1 cm and the hippocampal Schaffer-CA1 pathway is added. The experimental results show that the addition of wireless stimulation can modulate the transmission of synaptic electrical activity in the hippocampal Schaffer-CA1 pathway and significantly increase the level of (LTP) induction. A millimeter-scale wireless stimulation device is investigated and designed in this paper, the feasibility of the device is demonstrated through ex vivo electrophysiological experiments, and its effects on the targeted modulation of the Schaffer-CA1 pathway in the rat hippocampus are described. [ABSTRACT FROM AUTHOR]

This paper proposed an ultra-low-power successive approximation register analog to digital converter (ADC) for medical implant devices. To reduce power consumption, the novel techniques presented in this paper are a tri-state capacitor unit, a novel switch scheme, and a new low static power comparator. Tri-state capacitor unit reduces down power without the use of middle voltage reference. The proposed switch scheme can complete the most-significant bit 3-bit conversion without any power consumption. The offset of the low static power comparator is only optimized by physical design. This ADC is fabricated in a 110 nm 1P5M CMOS process. The reference voltage of DAC is 1 V, and the supply voltage of comparator and digital logic is 1.5 V. At 10 kS/s sampling rate, the signal to noise and distortion ratio (SNDR) is 57.57 dB and power consumption is 24 nW. [ABSTRACT FROM AUTHOR]

The micro-direct methanol fuel cell (μDMFC) has the advantages of high energy density, high conversion efficiency, and simple structure, which brought vast application prospects in portable devices. However, some shortcomings still exist, such as low catalyst utilization and power density. This paper proposes a new cathode electrode structure for the μDMFC. The structure consists of a multi-walled carbon nanotube layer and a cathode double microporous layer (CD-MPL) prepared from carbon powder. The outer microporous layer (OMPL) is composed of multi-walled carbon nanotubes (MWCNTs), Nafion solution, and carbon powder, and the inner microporous layer (IMPL) is composed of carbon powder and polytetrafluoroethylene (PTFE). The experimental results show that the maximum power density of the μDMFC with a CD-MPL (CD-μDMFC) is 42.8 mW/cm2, which is 31.6% higher than that of the μDMFC with a cathode single microporous layer (CS-μDMFC). The pore size distribution of the OMPL of the CNT is measured by the mercury intrusion method. It can be seen that the distribution of pore size is wider and there are more pores with larger pore sizes, which are more conducive to the utilization of catalysts. The discharge experiment of the cell shows that the CD-μDMFC shows high discharge performance and fuel utilization at different concentrations. The double microporous layer (MPL) structure increases the porosity and pore range, broadens the three-phase interface for the reaction, and allows the catalyst to have more attachment sites. The existence of MWCNTs improves the conductivity and mass transfer capacity of the cathode. [ABSTRACT FROM AUTHOR]

In this paper, an improved coupled-mode method is used to design a launcher for a gyrotron quasi-optical mode converter at 170 Ghz with an operating mode of TE32,9. The new method calculates 25 coupled modes, which more accurately simulates the field distribution in the launcher. The diffraction field of the launcher with a spiral cut is calculated by using the scalar diffraction integral method with fast Fourier transform. The radiation power of the launcher is 99.94%, the Gaussian mode content of the radiation beam is 98.40%, the diffraction loss of the launcher is 0.0580%, and the radiation efficiency is 98.34%. The method proposed in this paper is fast in calculation and can be applied to the large-scale high-frequency gyrotron launcher. [ABSTRACT FROM AUTHOR]

In this paper, the magnetic immunity model of STT-MRAM is established. The influence of the external magnetic field on the effective energy barrier of STT-MRAM is investigated, which is the crucial issue to influence the reliability of STT-MRAM cells in the standby, active read and active write modes. The influence factors on the magnetic immunity of STT-MRAM array are also discussed in the paper, such as the electrode, package material, insert layer and array spacing, etc. Moreover, the magnetic shield models in the BGA and QFP packages are designed and analyzed for the enhancement of the magnetic immunity of STT-MRAM, whose shielding efficiency is up to 98.2%. [ABSTRACT FROM AUTHOR]

With the advancement of wide-bandgap power devices, the power electronics equipment is developing toward higher switching frequencies and more complex switching modes in recent years. Accurate prediction of the core loss for magnetic components has been emphasized as the excitations of magnetic materials varying depending on the operating mode of the power supplies. Therefore, this paper presents the results of an extensive core loss study performed on nanocrystalline alloy (FT-3KL), amorphous alloy (1K101) and ultra-thin oriented silicon steel (GT-50). Firstly, an automatic setup for core loss measurement of soft magnetic materials fed by a full-bridge inverter based on silicon carbide (SiC) MOSFET is proposed. Then, the effects of switching oscillations from the inverter and the characteristic parameters of complex non-sinusoidal excitations on the core loss are analyzed comparatively. The core loss shows different regular distributions with the change of each characteristic parameter of excitations respectively. However, the regular distributions will be influenced by the high-frequency switching oscillations, which makes the prediction of core loss more complicated. This paper can provide a reference for the development of high-precision core loss model and performance optimization of power electronics equipment. [ABSTRACT FROM AUTHOR]

Electrical steel cores in electric motors are often operated under variable temperature conditions, and the temperature has a large impact on the magnetic properties of electrical steel. Different Silicon content also makes electrical steel have different performance characteristics. Therefore, in this paper, an environmentally adjustable electrical steel magnetic property testing system is built to investigate the magnetic property variation of non-oriented electrical steel sheets with different Si contents at different temperatures. Through the experiments in this paper, it is found that the trend of magnetic properties of electrical steels tends to flatten out with increasing Si content under the influence of temperature. In particular, the loss of 6.5% Si shows a trend of first decreasing and then increasing with the increase of temperature. The internal grain structure of electrical steel can explain this phenomenon very well. The larger the grain size, the less the magnetic properties of electrical steel are affected by temperature. In order to further analyze the variation phenomenon of electrical steel loss, the loss separation calculation was carried out for 5 more electrical steels with different Si content in this paper. The reason for this phenomenon was finally explained by a special preparation process of 6.5% Si. [ABSTRACT FROM AUTHOR]

In the paper, novel multi-bit parallel pipeline circuit design of STT-MRAM is proposed to improve the read and write efficiency. The shift register is utilized to change the series data into the parallel ones. Combined with the corresponding sense amplifier (SA) circuit and the write drive circuit, 4-bit data can be read or written in parallel in single cycle. With the 32 Kbit data test, the efficiencies of the read and the write operations of the proposed pipeline circuit are increased by 72.3% and 74.4%, separately, with the comparison of the incumbent series operations. The proposed strategy has potential application in the embedded high speed STT-MRAM. [ABSTRACT FROM AUTHOR]

In this paper, a low dropout (LDO) circuit based on a curvature compensation benchmark and closed-loop stability is designed. This circuit compensates for the higher order term of VBE in a BJT through the subthreshold characteristic of MOSFET and achieves the effect of curvature compensation. The bandgap reference circuit provides a stable input voltage for the LDO circuit, while the source follower and adaptive bias circuit improve the response speed and closed-loop stability of the LDO circuit. The temperature drift coefficient of the bandgap circuit is 8.11 ppm/°C, the input voltage is 3–5 V, the output voltage is 2.8 V, and the linear adjustment rate is 0.22%. [ABSTRACT FROM AUTHOR]

In my recent paper (hereafter "LU-ADV22"),[1] I used the Trajectory-mapped Ozonesonde dataset for the Stratosphere and Troposphere (TOST) obtained from the World Ozone and Ultraviolet Radiation Data Center (WOUDC),[[2]] latitude-altitude chlorofluorocarbon (CFC) distribution, time-series total ozone, Ozonesonde and Umkehr datasets, and lower stratospheric temperature climatology from multiple ground-based or satellite measurements to reveal the tropical ozone hole. The NOAA's BDBP Tier 1.4 dataset[[7]] is a vertically resolved, global, gap-free, and zonal mean dataset, which was created with a multiple-linear regression model based on monthly mean ozone concentrations that were calculated from several different satellite instruments and global ozone soundings, covering the period 1979-2007. 2, middle panel), and is comparable to the decrease of 5%-6% in total ozone or stratospheric ozone columns above 68 hPa at near-global (60°S-60°N) reported by Froidevaux I et al. i using the GOZCARDS data.[5] Second, reading throughout the paper by Weber I et al. i ,[39] one can find that they reported ozone trends using five merged zonal mean total ozone datasets from satellite and ground-based observations for the period of 1979-2020, instead of starting from 1964. According to the description by Liu I et al. i ,[2] the TOST ozone climatology has the following advantages: (1) it is 3D (latitudinally, longitudinally, and vertically) resolved; (2) its ozone data are obtained from an independent source and covers a record since 1965 that is twice as long as the satellite record; and (3) most crucially, I it depends on neither a priori dataset nor photochemical modeling and thus provides independent information and insights that can supplement satellite data and model simulations and enhance our understanding of stratospheric ozone i . [Extracted from the article]

Aiming at the application requirements of multi-target microwave energy transmission, this paper proposes a multi-target microwave energy focusing method based on the genetic algorithm. This method optimizes the feeding phase first and then optimizes the feeding amplitude. By optimizing the feeding phase, the microwaves radiated by the antenna array unit tend to be superimposed in phase at each target point; furthermore, the energy distribution on the focal plane is optimized by optimizing the feeding amplitude. Two-target and three-target focusing methods are taken as examples to conduct microwave energy focusing simulation research. The results show that by using optimized-phase optimized-amplitude feeding, the total electric field strength at the two target points and the three target points is increased by 13% and 8.7%, respectively, compared with the optimized-phase constant-amplitude feeding. A 6 × 6 microstrip antenna array working at 5.8 GHz is designed to conduct two-target and three-target microwave energy focusing experiments. The experimental results verify the effectiveness of the multi-target focusing method proposed in this paper. [ABSTRACT FROM AUTHOR]

In this paper, finite element models of ultrasonic wave propagation in Cu–PMMA composites are established. The effects of second-phase particles, ultrasonic properties, and graded interfaces on the ultrasonic propagation behavior are investigated, and the contributions of particle-independent scattering, particle interactions, and matrix viscoelasticity to the ultrasonic attenuation are quantitatively evaluated. The results show that there is no obvious coupling between particle scattering and matrix viscoelasticity in Cu–PMMA composites, and the longitudinal wave speed has little effect with the variation of particle size, ultrasonic frequency, and graded interface, while the variation of the acoustic attenuation coefficient is related to the disorder of ultrasonic energy propagation direction. In the intra-layer uniform model, with the increase in Cu particle size and ultrasonic frequency, the scattering effect of Cu particles on the ultrasonic waves is enhanced, resulting in a significant increase in the acoustic attenuation coefficient. In the inter-layer graded multilayer model, there is a strong reverse energy propagation between the layers, causing the acoustic attenuation coefficient to increase significantly. [ABSTRACT FROM AUTHOR]

The thermodynamic efficiency of a wire mesh fixed matrix regenerative heat exchanger mainly depends on the regenerator's heating performance and losses. This paper aims to increase the effectiveness and decrease the pressure loss of static regenerators with wire mesh screens as packing geometry. The entropy generated for several combinations of mesh screens is calculated by using the entropy generation minimization method (EGM), and this method helps in finding the right combination with the minimum entropy generation. The study aims to minimize entropy generation by dividing the conventional uniform mesh regenerator pack length into multiple zones by accommodating different combinations of wire mesh screens. For the sample flow condition, it is observed that 3.94 × 103 W/K entropy is generated by uniform mesh, and from 68 hybrid mesh combinations, 80–120–200 generated 2.11 × 103 W/K. By balancing pressure loss and thermal efficiency, the potential of EGM-based optimization is underscored during this study, which improves the regenerator's performance. [ABSTRACT FROM AUTHOR]

Exploring very-large-scale motions (VLSMs) in open channel flows (OCFs) is crucial for comprehensively understanding material transport and energy exchange. While previous studies focused on OCFs in ideal flumes with simple boundaries, this paper presents large eddy simulation (LES) results on the existence and scale characteristics of VLSMs in complex river morphologies with the Minjiang River in southwestern China as a case study. This research demonstrates that the OpenFOAM-based LES model is capable of accurately reconstructing the time-averaged flow field and providing instantaneous velocity data that capture VLSMs with sufficient resolution. Spectrum analysis of the streamwise fluctuating velocity shows that VLSMs are present in the straight segment of the river, with streamwise wavelengths approximately (16–22) times the water depth but are absent in the bend and confluence segments due to the suppression by secondary currents. This article validates the effectiveness of LES in examining the characteristics of VLSMs in natural rivers, thereby laying a good foundation for further studies on the impacts of such structures on sediment transport and pollutant dispersion. [ABSTRACT FROM AUTHOR]

The efficient utilization of renewable energy is a key technology area of high domestic and international concern, and the research and development of DC–DC photovoltaic converters with high conversion efficiency is of great significance for improving performance and reducing the cost of solar power generation systems. In order to improve the conversion efficiency of solar energy, this paper proposes the design of a high-efficiency photovoltaic DC–DC converter with a non-isolated DC–DC converter as the object of the study. Solar power conversion is accomplished by designing a simple and reliable snubber circuit and a triode auxiliary circuit and tracking the maximum power point by combining the perturbation observation method with variable step size. The snubber circuit can effectively suppress the problems of pulse spikes and oscillations, and the triode auxiliary circuit prevents the reverse current and improves the switching speed, which reduces the switching loss and combines with the perturbation observation method with variable step size for fast and stable tracking of the maximum power point. In order to verify the feasibility of the converter, a 600 W prototype is designed. The experimental results show that using the snubber circuit reduces the pulse spike by 4.2 V and the overshoot is reduced by 4.3%. The maximum conversion efficiency is increased by 0.88% with the use of the transistor-assisted circuit, and the tracking efficiency of the MPPT is still stable under cloudy conditions. The maximum conversion efficiency of the prototype is finally measured to be up to 98.12%. [ABSTRACT FROM AUTHOR]

The generation of abrasive particles is an unavoidable consequence of sliding electrical contact wear in conductive slip rings (SRs). The adhesion of abrasive particles to the insulators may lead to a decrease in flashover voltage, posing a risk to satellite power transmission. In this paper, the effect of abrasive particles on flashover is first studied. Surface abrasive particles can distort the surface electric field of the dielectric, absorb scattered electrons, and then re-emit them, thereby accelerating the development and formation of secondary electron avalanches. Flashover test results indicate that surface abrasive particles lead to a significant reduction in flashover voltage. To mitigate the impact of particle adhesion on flashover, a method of constructing particle traps on the surface of insulators is proposed. The location and structural parameters of the particle trap are further optimized and determined. The flashover test results using planar dielectric samples and SR insulator samples both demonstrate that the optimized particle trap can significantly improve the flashover voltage. The dielectric maintains high electrical strength even when particles are trapped in particle traps. The physical details of the impact of particles on flashover and the effect of particle traps are analyzed utilizing an electron movement simulation, corroborating the experiment from a microscopic aspect. [ABSTRACT FROM AUTHOR]

Concentration plays an essential role in generating hydroxyl radicals in irradiated nanoenhancer suspensions. In this paper, we used coumarin-3-carboxylic acid as a hydroxyl radical-specific probe to investigate the hydroxyl radical production of different concentration nanodiamonds (NDs) and CeO2 NPs in phosphate-buffered saline under x-ray irradiation. NDs significantly enhanced hydroxyl radical production, and the maximum enhancement of hydroxyl radical production was observed at a concentration of 10 µg/ml, with an enhanced factor of 1.398 ± 0.262. CeO2 NPs can increase and scavenge hydroxyl radicals at different concentration ranges, with the lowest and highest enhanced factors of 0.623 ± 0.069 and 1.738 ± 0.264, respectively. We tested the hydrodynamic diameter at various concentrations to explore the concentration effect further. We found that with increasing concentration, there might be factors, such as hydroxyl radical recombination and nanoparticle agglomeration, that lead to changes in the enhancement factor. Based on the data from previous and present studies, the experimental results indicate that the concentration factor is essential for hydroxyl radical generation in nanoenhancer suspensions under ionizing radiation. We also provide possible mechanisms for enhancing hydroxyl radical production by nanoenhancers in water under ionizing radiation and the decrease in enhancement factor at high concentrations of nanoenhancers. [ABSTRACT FROM AUTHOR]

To separate the complexities in plasma physics and geometric effects, compact formulas for local geometric properties of a tokamak equilibrium are presented in this paper. They are written in a form similar to the Frenet formulas. All of the geometric quantities are expressed in terms of curvature and torsion of the three spatial curves for the moving local frame of reference, i.e., local orthogonal vector basis. In this representation, the local magnetic shear and the normalized parallel current are just the differences between two torsions of the vector basis. All of the geometric properties are coordinate invariants and form a prime set of quantities for describing tokamak plasma equilibrium. This prime set can be evaluated in both flux coordinates with closed flux surfaces and cylindrical coordinates including areas with open field lines, which may allow the extension of some analysis on the open field lines outside the last closed surface. Fundamental differential operators for stability and transport studies can be expressed explicitly in terms of these geometric properties. It can also be used to simplify analytic studies. [ABSTRACT FROM AUTHOR]

This paper thoroughly investigates the analysis of a modified generalized mean-field Ising model. The thermodynamic limit of free energy is investigated, and both the upper and lower bounds are derived. The lower bound is derived using a standard entropic variational principle, whereas a decoupling method is employed to derive the upper bound. Although the two bounds differ in form, they exhibit the same local maxima. Finally, the impact of a slight external field on the magnetic order is analyzed. [ABSTRACT FROM AUTHOR]

Renewable energy sources such as wind and solar power exhibit strong stochasticity and volatility, resulting in decreased power supply security and sustainability. A strategically optimized hybrid renewable energy system (HRES) is crucial for maintaining stable load operations and achieving sustainable energy development. This paper introduces an energy optimization management model for an independent HRES consisting of wind turbines, photovoltaic systems, diesel generators, and energy storage units. Operational strategies focus on energy storage-led loads following diesel generator-led load prioritizations. The model aims to optimize objectives to include economic, environmental, and power supply reliability indices. A dynamic adaptive parameter approach balances the parameters of the objective function at various instances. The optimal capacity allocation of the model is solved using the improved gray wolf optimization (IGWO) algorithm. This approach incorporates the golden sine strategy, the levy flight strategy, and the dynamic inverse learning strategy into the traditional GWO algorithm. Analyzing different test functions, evaluation metrics, and actual load data indicates that the proposed algorithm excels in global optimization capabilities and search speeds. The model significantly reduces the economic and environmental costs of the HRES microgrids and improves the sustainable development of renewable energy in various scenarios. [ABSTRACT FROM AUTHOR]