For the lossy matching network, the efficiency of transferring the power is one of the most important factors. In this brief, a novel generalized quality-based equation has been derived which can accurately calculate ...
详细信息
For the lossy matching network, the efficiency of transferring the power is one of the most important factors. In this brief, a novel generalized quality-based equation has been derived which can accurately calculate the efficiency. This generalized equation covers all the situations that the source and load impedance are both complex and consider both the loss of inductor and capacitor. Meanwhile, the SPICE simulations have been carried out to validate the accuracy of the proposed equation. Based on this generalized equation, a top-down splitting algorithm is proposed to further optimize the efficiency of multi-stage matching network. The proposed method shows better improvement of efficiency than prior works.
The multi-level inverter (MLI) is advantageous for DC to AC voltage conversion in power distribution networks. The low-power applications require square and quasi-square waveforms, whereas the sinusoidal waveform is r...
详细信息
The multi-level inverter (MLI) is advantageous for DC to AC voltage conversion in power distribution networks. The low-power applications require square and quasi-square waveforms, whereas the sinusoidal waveform is required in high-power applications. The pure sinusoidal waveform of an inverter is obtained by improving the number of levels in the inverter. Hence, more switches and DC sources are used in the inverters to produce multi-levels at the output. The large number of switches and DC sources increases harmonics in the system. The modulation techniques are used with the MLI topologies to alleviate these issues. Recently, modulation techniques based on optimization algorithms have been used to minimize Total Harmonic Distortion (THD). This paper reviews optimization algorithm-based modulation techniques in the recent literature. This review aims to provide an effective solution for enhancing THD in MLI. Different MLI types are initially explained, and then the recent algorithms are explained for THD minimization.
The space-based infrared LEO constellation has the ability of surveillance and tracking of ballistic missiles during entire phases, which has played an important role in the ballistic missile defense system (BMDS). Th...
详细信息
The space-based infrared LEO constellation has the ability of surveillance and tracking of ballistic missiles during entire phases, which has played an important role in the ballistic missile defense system (BMDS). This paper focuses on the scheduling strategy for the LEO constellation to multiple targets. The concept of average contribution of the satellite is firstly introduced, transforming the dynamic scheduling process to continuous intervals. The switching frequency and relaxation degree are also considered as decision variables. Then the multilayer coding genetic algorithm is improved in order to solve the scheduling problem. Finally, a scheduling demonstration validates the correctness and effectiveness of the presented method. The theory analysis and simulation results of this paper can provide powerful support for future design of the LEO constellation and research on the BMDS.
Uncertainty quantification plays a crucial role in the design, monitoring, and risk assessment of earth dams. To reduce the computational burden, we employ a combination of finite difference method and soft computing ...
详细信息
Uncertainty quantification plays a crucial role in the design, monitoring, and risk assessment of earth dams. To reduce the computational burden, we employ a combination of finite difference method and soft computing techniques to investigate material uncertainties in earth dams during the initial impoundment stage. The findings of sensitivity analysis with the Tornado diagram indicate that key material properties such as dry density, elasticity modulus, friction angle, and Poisson's ratio significantly influence the displacements and stress analysis. In our study, we explore four variants of extreme learning machines (ELMs): the standalone ELM, hybridized versions with the improved grey wolf optimizer algorithm, ant colony optimization for continuous domains, and artificial bee colony. These methods are assessed across various training sizes to predict multiple parameters, including horizontal and vertical displacements, stresses, and the factor of safety (FoS). The hybridized ELM with the improved grey wolf optimizer algorithm emerges as the superior choice for most of the response variables. A minimum of 200 numerical simulations is required to establish a stable and accurate meta-model with an average prediction error of less than 3% for responses and the FoS.
The biggest challenge of this article is how to maximize the rest time of intermittent controllers. This paper mainly uses intermittent quantized controller (IQC) to examine asymptotic synchronization between fraction...
详细信息
The biggest challenge of this article is how to maximize the rest time of intermittent controllers. This paper mainly uses intermittent quantized controller (IQC) to examine asymptotic synchronization between fractional-order neural networks (FONNs). Firstly, by utilizing the advantages of intermittent properties, a novel lemma with asymptotic stability inequalities is proposed. Secondly, combining intermittent properties with quantization technique, two different categories of aperiodically intermittent quantized controllers (AIQCs) are designed to ensure asymptotic convergence of FONNs. Due to the certain correlation between control interval, rest interval, and convergence rate parameters, thus, optimization algorithm becomes particularly important in maximizing rest time as much as possible. Thirdly, by constructing Lyapunov functions, several useful conditions are established for the asymptotic synchronization of FONNs. Finally, the rationality of the proposed theoretical analysis is confirmed by two numerical examples.
This study presents an application of the self-organizing migrating algorithm (SOMA) to train artificial neural networks for skin segmentation tasks. We compare the performance of SOMA with popular gradient-based opti...
详细信息
This study presents an application of the self-organizing migrating algorithm (SOMA) to train artificial neural networks for skin segmentation tasks. We compare the performance of SOMA with popular gradient-based optimization methods such as ADAM and SGDM, as well as with another evolutionary algorithm, differential evolution (DE). Experiments are conducted on the skin dataset, which consists of 245,057 samples with skin and non-skin labels. The results show that the neural network trained by SOMA achieves the highest accuracy (93.18%), outperforming ADAM (84.87%), SGDM (84.79%), and DE (91.32%). The visual evaluation also reveals the SOMA-trained neural network's accurate and reliable segmentation capabilities in most cases. These findings highlight the potential of incorporating evolutionary optimization algorithms like SOMA into the training process of artificial neural networks, significantly improving performance in image segmentation tasks.
To analyze the state of anaerobic digestion (AD), fast detection models of volatile fatty acids (VFAs) were constructed using near-infrared transmission spectroscopy combined with partial least squares regression to m...
详细信息
To analyze the state of anaerobic digestion (AD), fast detection models of volatile fatty acids (VFAs) were constructed using near-infrared transmission spectroscopy combined with partial least squares regression to measure concentra-tions of the acetic acid (AA), propionic acid (PA) and total acid (TA) in biogas slurry. CARS-SA-BPSO algorithm was proposed based on competitive adaptive reweighted sampling (CARS) and simulated annealing binary particle swarm optimization algorithm (SA-BPSO) for selecting feature wavelengths of the AA, PA and TA. Regression models were established with the determination coefficient of prediction (Rp2) of 0.989, root mean squared error of prediction (RMSEP) of 0.111 and residual predictive deviation (RPD) of 9.706 for AA;Rp2 of 0.932, RMSEP of 0.116 and RPD of 3.799 for PA;Rp2 of 0.895, RMSEP of 0.689 and RPD of 3.676 for TA. It is sufficient to meet the fast detection needs of the AA and PA concentrations in biogas slurry, and basically meet the measuring demand of the TA concentration. CARS-SA-BPSO effectively improves the performance of the calibration model using sensitive wavelength selections, which provides theoretical support for establishing the spectral quantitative regression model to meet the require-ments of practical application.
While the rain gauge measurements are unevenly distributed in many world regions, it is necessary to use remote sensing-based precipitation data at high spatial and temporal resolutions. On the other hand, quantifying...
详细信息
While the rain gauge measurements are unevenly distributed in many world regions, it is necessary to use remote sensing-based precipitation data at high spatial and temporal resolutions. On the other hand, quantifying the uncertainty of precipitation is a vital issue for hydrometeorological applications globally. For this purpose, applying a new fusion framework using high-resolution remote sensing datasets can provide accurate precipi-tation evaluation against local observations with low uncertainty. This study examines three weighted fusion -based models containing the Ordered-Weighted-Averaged (OWA) family approach based on the ORLIKE method (OWA-ORLIKE) and ORNESS method (OWA-ORNESS) as well as the Entropy-weight (EW) method to combine different remote sensing precipitation products over different climate zones of Iran. In this case, mul-tiple monthly remotely sensed datasets, including ERA5, ERA5-Land, TerraClimate, GPM, PERSIANN-CDR, TRMM, and CHIRPS, are utilized to assess precipitation patterns versus local measurements, which were gath-ered by Google Earth Engine (GEE) platform. Furthermore, the K-means algorithm is employed to cluster ground -based precipitation stations based on the climate zones category across Iran. Additionally, the Genetic Optimi-zation algorithm (GOA) is applied to specify optimal values of weights in weighting-based models. The per-formance of single and combination datasets are evaluated using statistical error metrics, including Pearson correlation coefficient (PCC), root mean square error (RMSE), Kling Gupta efficiency (KGE), and bias. The Thiessen polygon method has been applied to calculate each cluster's mean precipitation to obtain the optimal weights of stations. Finally, as an efficient uncertainty approach, Cross Wavelet Transform (XWT) method has been used for uncertainty assessment of monthly and seasonal precipitation series. Results indicated that the OWA family as the best fusion model had almost the lowest uncertaint
This article presents a novel approach to estimate the flexural capacity of reinforced concrete-filled composite plate shear walls using an optimized computational intelligence model. The proposed model was developed ...
详细信息
This article presents a novel approach to estimate the flexural capacity of reinforced concrete-filled composite plate shear walls using an optimized computational intelligence model. The proposed model was developed and validated based on 47 laboratory data points and the Transit Search (TS) optimization algorithm. Using 80% of the experimental dataset, the optimized model was selected by determining the unknown coefficients of the network-based computational structure. The remaining 20% of the data was used to evaluate the accuracy of the model, and the best-performing structure was selected. Furthermore, the final neural network details were subjected to statistical analysis to extract a user-friendly formula, making it easier to apply in practice. The proposed ANN model and the proposed user-friendly formula were then compared with the AISC 341-16 and experimental results and demonstrated their efficacy in predicting the flexural behavior of composite shear walls. Overall, the proposed approach provides a more reliable and efficient framework for estimating the flexural behavior of composite shear walls.
暂无评论