A novel nature-inspired meta-heuristic optimization algorithm, named artificial ecosystem-based optimization (AEO), is presented in this paper. AEO is a population-based optimizer motivated from the flow of energy in ...
详细信息
A novel nature-inspired meta-heuristic optimization algorithm, named artificial ecosystem-based optimization (AEO), is presented in this paper. AEO is a population-based optimizer motivated from the flow of energy in an ecosystem on the earth, and this algorithm mimics three unique behaviors of living organisms, including production, consumption, and decomposition. AEO is tested on thirty-one mathematical benchmark functions and eight real-world engineering design problems. The overall comparisons suggest that the optimization performance of AEO outperforms that of other state-of-the-art counterparts. Especially for real-world engineering problems, AEO is more competitive than other reported methods in terms of both convergence rate and computational efforts. The applications of AEO to the field of identification of hydrogeological parameters are also considered in this study to further evaluate its effectiveness in practice, demonstrating its potential in tackling challenging problems with difficulty and unknown search space. The codes are available at.
A framework has been designed to optimize the performance of two-element airfoils using an open-source physics informed neural network solver under certain aerodynamics constraints, The solver used is the Nvidia Modul...
详细信息
ISBN:
(数字)9781624107115
ISBN:
(纸本)9781624107115
A framework has been designed to optimize the performance of two-element airfoils using an open-source physics informed neural network solver under certain aerodynamics constraints, The solver used is the Nvidia Modulus. The objective function is constructed such that with a single training, it can predict the flow fields and force coefficients for a range of angles of attack and airfoil thickness. optimization is then performed using the trained network to improve the airfoil performance. Results show that this trained network can predict the flow fields and force coefficients with reasonable accuracy much faster than traditional computational fluid dynamics solvers. When coupled with an optimization routine, it can also predict maximum cl, cl/cd and endurance coefficient.
This study proposes a high-precision method for retrieving sea surface salinity (SSS) using GF-1 satellite imagery, focusing on Qinzhou Bay along the Guangxi coast. The analysis identified the spectral index B3xB4/(B1...
详细信息
This study proposes a high-precision method for retrieving sea surface salinity (SSS) using GF-1 satellite imagery, focusing on Qinzhou Bay along the Guangxi coast. The analysis identified the spectral index B3xB4/(B1xB2) as having the strongest correlation with SSS (R = 0.929). To enhance the performance of the Back Propagation Neural Network (BPNN) model, optimization algorithms including Improved Grey Wolf optimization (IGWO), Particle Swarm optimization (PSO), and White Shark optimization (WSO) were applied. Comparative results show that IGWO significantly optimized network weights and thresholds, yielding superior test performance metrics (MAE = 0.906 psu, MAPE = 4.124%, RMSE = 1.067 psu, and R2 = 0.953), demonstrating strong generalization ability. Validation using third-party data indicated accuracy reductions of 10.9% and 8.6% in Qinzhou Bay and Tieshan Port, respectively, highlighting the model's robustness and broad applicability. SSS retrieval results for Qinzhou Bay in 2023 revealed significant spatial and seasonal variations: the Inner Bay exhibited lower salinity (average 14 psu) from April to September due to freshwater inflows, while salinity increased (average 22 psu) from November to February. The Outer Bay, influenced by its connection to the South China Sea, maintained consistently high salinity levels (25-30 psu) year-round. Additionally, different models showed varying levels of effectiveness in Qinzhou Bay's complex salinity environment;the IGWO-BPNN model, with its dynamic weight adjustment mechanism, demonstrated superior adaptability in areas with high salinity variability, outperforming other models. These findings suggest that the IGWO-BPNN model provides high accuracy and stability, supporting real-time, precise monitoring in Qinzhou Bay and similar coastal waters, thereby offering robust support for water quality management and marine conservation.
Beam splitters are an important part of optical systems and have a wide range of applications in wireless communications and target detection. In this study, bendable structures based on subwavelength nanostructured m...
详细信息
Beam splitters are an important part of optical systems and have a wide range of applications in wireless communications and target detection. In this study, bendable structures based on subwavelength nanostructured metasurfaces with an arbitrary number of beams are constructed. To achieve multiple beams, the phase distribution of a multi-beam splitting metasurface in the 2D direction is calculated directly by an optimized phase recovery algorithm. The cells exhibiting high polarization conversion efficiency are arranged periodically according to the discrete phase. By full-wave simulation, the beam-splitting metasurfaces realize 2 x 2, 4 x 4, and 6 x 6 main beams with high power efficiency and homogeneity from 0.2 THz to 0.37 THz. In addition, the effect of metasurface bending on beam splitting is further investigated using flexible materials that can be fitted into more devices. It is demonstrated that the performance remains optimal at curvatures of less than 1/10,000 mu m-1. Due to the 2D structure, this beam splitter allows electromagnetic waves to be incident at an angle of more than 40 degrees for more demanding applications. Finally, a flexible beam splitter fabrication method based on commercially available polyimide films is proposed and measured, and the results are in agreement with the simulation results. Compared to other beam splitters, the flexible metasurface is fabricated in this paper to reduce the cost, is suitable for large-scale production, and is easy to integrate. These devices can be used in THz optical systems, as well as in mobile applications.
Insulated gate bipolar transistors (IGBTs) are the key component in power electronics, and the intricate relationship between their performance and structural parameters poses a formidable challenge in the design proc...
详细信息
Insulated gate bipolar transistors (IGBTs) are the key component in power electronics, and the intricate relationship between their performance and structural parameters poses a formidable challenge in the design process. This article proposes an automatic optimal design method for IGBT structural parameters to leverage the pretrained machine learning (ML) model to efficiently predict the initial IGBT device's performance, followed by utilizing the differential evolution (DE) algorithm to automatically adjust structural parameters based on the disparity between predicted and expected device performance until the expected performance is achieved. The method is validated in the design of punch-through IGBTs (PT-IGBTs) and trench gate field-stop IGBTs (FS-IGBTs), and the performance of technology computer-aided design (TCAD) simulation of the designed device is similar to the target performance. In particular, the simulation results of the designed FS-IGBT are highly fitted to the datasheet of the commercial device, which verifies the generalizability and effectiveness of the method. In addition, comparative analyses with various algorithms show DE provides the fastest optimization and extraordinary robustness under the exact specifications. Crucially, the proposed design scheme aligns with semiconductor physics. The method simplifies IGBT design without the need for manual tuning and TCAD tool simulation.
Transfer functions have a very important role in metaheuristic optimization-based feature selection algorithms as these functions map the continuous search space into binary space. The U-shaped transfer function (UTF)...
详细信息
Transfer functions have a very important role in metaheuristic optimization-based feature selection algorithms as these functions map the continuous search space into binary space. The U-shaped transfer function (UTF) is one of the transfer functions used to solve the problem of feature selection. However, the UTF requires the selection of parametric values, which can vary for different types of data. To address this issue, an approach to select the parameters of the UTF has been proposed based on a time-varying adaption method, resulting in the modified U-shaped transfer function (MUTF). Furthermore, a methodology has been proposed to enhance feature selection and classification for Parkinson's disease by utilizing z-score normalization in conjunction with a modified U-shaped transfer function and the binary self-adaptive bald eagle search (MUTF-SABES) optimization algorithm. The z-score normalization has been used to mitigate issues caused by outliers. Also, the performance of the k nearest neighbor classifier is improved by selecting an optimal parameter value using the proposed MUTF-SABES algorithm. The effectiveness of the proposed methodology is validated on seven different Parkinson's disease datasets and compared with five state-of-the-art optimization algorithms: Salp Swarm algorithm, Harris Hawks optimization, equilibrium optimizer, aquilla optimizer, and Honey Badger algorithm, to evaluate its performance superiority. The results achieved using the proposed approach have been superior or analogous to the erstwhile algorithms for performance comparability. Friedman's mean rank test is used to check the statistical significance of the propounded approach. The lowest Friedman's mean rank value obtained using the proposed approach indicates that the proposed approach has the potential to become an alternative to other well-known strategies.
This manuscript describes a methodology for simultaneous vehicle and trajectory optimization of a hypersonic glide vehicle. The co-design problem is formulated as an optimization problem with constraints including veh...
详细信息
ISBN:
(数字)9781624107115
ISBN:
(纸本)9781624107115
This manuscript describes a methodology for simultaneous vehicle and trajectory optimization of a hypersonic glide vehicle. The co-design problem is formulated as an optimization problem with constraints including vehicle dynamics, path constraints (e.g., surface heating), and other constraints. The discretized optimization problem is solved simultaneously in the vehicle design parameters, the state variables, and the controls using an interior point method. Gaussian process (GP) surrogates, which are generated from sample candidate designs and flight conditions, are used to model vehicle aerodynamic performance and mass properties, as well as their first and second-order derivatives required by the optimizer. These GP surrogates and their derivatives are computationally inexpensive, making the all-at-once optimization approach for the co-design problem more tractable. To mitigate the effect of surrogate model errors on the solution of the optimal control problem, the GP models are refined using samples of the vehicle aerodynamic performance and mass properties at the solution of the co-design problem with the current surrogate. The resulting framework is applied to maximizing the range of a hypersonic glide vehicle with path and terminal constraints. Possible extensions of this methodology are also discussed, including the incorporation of more complex vehicle models such as multi-fidelity models, as well as adaptive surrogate modeling strategies to mitigate the effect of model errors on the solution of the optimal control problem.
This paper introduces an efficient approach for compact, wideband and supergain arrays design using artificial neural network (ANN) based optimization. The proposed method optimize at the same time the distance inter-...
详细信息
This paper introduces an efficient approach for compact, wideband and supergain arrays design using artificial neural network (ANN) based optimization. The proposed method optimize at the same time the distance inter-elements of the array antenna, its input impedance as well as its directivity. Such global optimization considerably improves the performances of superdirective arrays in terms of gain, bandwidth and efficiency. The proposed method is used afterwards to synthesize a three-elements array using two different unit elements. The comparison of the achieved performances and the Harrington limit reveals that the developed antennas can be qualified as supergain antennas. To our knowledge, this is the first demonstration of a wideband supergain array with more than two elements in the open literature. To validate the results, a prototype was manufactured and measured. The measurements show that the antenna has a wide impedance bandwidth of 22.6%, a peak directivity of 8.3 dBi and a total efficiency greater than 80%.
Amidst the increasing incorporation of multicarrier energy systems in the industrial sector, this article presents a detailed stochastic methodology for the optimal operation and daily planning of an integrated energy...
详细信息
Amidst the increasing incorporation of multicarrier energy systems in the industrial sector, this article presents a detailed stochastic methodology for the optimal operation and daily planning of an integrated energy system that includes renewable energy sources, adaptive cooling, heating, and electrical loads, along with ice storage capabilities. To address this problem, it applies the 2 m + 1 point estimation method to accurately assess system uncertainties while minimizing computational complexity. The "2 m + 1 point" technique swiftly evaluates unpredictability through Taylor series calculations, capturing deviations in green energy output, and the demand for both electric and thermal energy across power networks, while also considering the oscillating costs associated with senior energy transmission systems. In addition, this article proposes a novel self-adaptive optimization technique, called the enhanced self-adaptive mucilaginous fungus optimization algorithm (SMSMA), dedicated to overcoming the intricate nonlinear challenges inherent in the optimal daily operation of an energy system. The advanced self-adaptive strategy relies on wavelet theory to enhance the capability and effectiveness of the original mucilaginous fungus algorithm in optimizing daily schedules for an integrated energy system. Numerical analyses demonstrate that the introduced stochastic daily scheduling framework, coupled with the SMSMA optimization algorithm, effectively reduces the operating costs of the energy system.
暂无评论