This study presents an innovative approach to optimize energy management in residential microgrids, in light of the rising demand for energy and mounting environmental concerns. The research underscores the vital role...
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This study presents an innovative approach to optimize energy management in residential microgrids, in light of the rising demand for energy and mounting environmental concerns. The research underscores the vital role of efficient energy management and responsive load control to improve energy efficiency and reduce consumer costs. To this end, a framework is proposed in which a power aggregator operates within a microgrid to manage residential electricity consumption. The primary goal of this framework is to minimize energy costs while considering subscriber preferences and the capacity limitations of the distribution network. The improved particle swarm optimization (IPSO) algorithm is employed to optimize energy management, resolve convergence challenges, and ensure user requirements are effectively prioritized. Integrating emergency, economic, and planned strategies provides cost savings, ensures grid stability, and enhances user satisfaction. The incorporation of Internet of Things (IoT) technology enables seamless communication, precise device control, and data-driven decision-making, empowering households to manage their energy loads more effectively and contribute to grid efficiency. Through scenario analysis, this research demonstrates the IPSO algorithm's potential for significant cost reductions and improved grid stability. In Scenario 1, focused exclusively on affordability, numerical analyses present the total cost of electricity under different load conditions over three months. Scenario 2, also prioritizing affordability, highlights the impact of economic considerations on electricity expenses. Furthermore, Scenario 3 (80 % emergency + 20 % affordable) and Scenario 4 (50 % emergency + 20 % affordable + 30 % planned) showcase the potential for cost reduction through various priority combinations. These insights reflect the effectiveness of load management strategies facilitated by IoT technology. This comprehensive energy management approach lays a stro
A new algorithm for optimizing thermodynamic parameters of binary systems is introduced. Unlike traditional algorithms that are commonly single-objective and need extensive manual testing, this algorithm constructs a ...
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A new algorithm for optimizing thermodynamic parameters of binary systems is introduced. Unlike traditional algorithms that are commonly single-objective and need extensive manual testing, this algorithm constructs a multi-objective optimization for different types of experimental data. Then, by using weighted sum method, the multi-objective optimization problem is transformed into a single-objective optimization, which is solved by Barzilai-Borwein method. The key advantage of this algorithm is that no restrictions on the selection of initial values are needed. Finally, this algorithm is applied to optimize the thermodynamic parameters in the Ag-Pd and La-C systems. The experimental phase diagrams and thermodynamic properties in these two systems are satisfactorily reproduced by the present calculation.
In this paper, the steady-state optimization problem of S-type biochemical systems is investigated. A mathematical model of the S-type biochemical system is given. A nonconvex bi-objective optimization model with stab...
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In this paper, the steady-state optimization problem of S-type biochemical systems is investigated. A mathematical model of the S-type biochemical system is given. A nonconvex bi-objective optimization model with stability guarantees is constructed with the optimization objectives of maximizing the product yield and minimizing the sum of metabolite concentrations, which can ensure that the S-type biochemical system operates at an optimal and stable steady state. The nonconvex bi-objective optimization model is transformed into a nonconvex single-objective optimization problem based on the normal-boundary intersection (NBI) method. In order to efficiently solve the transformed nonconvex single-objective problem, a geometric programming algorithm is proposed based on the equivalence transformation and monomial compensation strategy, and the convergence analysis of the algorithm is given. An iterative solution algorithm for nonconvex bi-objective optimization model with stability guarantees is given based on this algorithm. The Pareto optimal solutions and Pareto optimal fronts of three different nonconvex bi-objective optimization models are obtained by computing three examples of S-type biochemical systems.
A hybrid approach for brain magnetic resonance imaging (MRI) image segmentation is proposed, that combines the intuitionistic particle swarm optimization (IPSO) algorithm and the kernel intuitionistic fuzzy entropy cm...
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A hybrid approach for brain magnetic resonance imaging (MRI) image segmentation is proposed, that combines the intuitionistic particle swarm optimization (IPSO) algorithm and the kernel intuitionistic fuzzy entropy cmeans (KIFECM) to overcome the local minima trapping problem of KIFECM. In terms of intuitionistic fuzzification, intuitionistic PSO (IPSO) is a global optimization technique that investigates random search with candidate solution. The hybrid KIFECM-IPSO technique combines the best aspects of IPSO and KIFECM algorithms to improve clustering outcomes and prevent the local minima entrapment issue. The performance of the algorithm can be evaluated using various measures such as the similarity measure, average similarity measure, jaccard coefficient, false negative ratio and false positive ratio on the real brain data and simulated brain data. The results have been compared with KIFECM, PSO-KIFCM, FEC, PSO and FCM-PSO algorithms to determine the effectiveness of the proposed algorithm and the experimental results shows that the proposed KIFECM-IPSO perform better. Friedman's statistical test is also carried out to demonstrate that the performance of the proposed algorithm is not only better but the performance difference is statistically significant also.
Energy saving and decarbonization become consensus of the world. Medium-depth ground source heat pumps employing coaxial borehole heat exchangers have emerged as a pivotal choice for low-carbon heating. Heat transfer ...
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Energy saving and decarbonization become consensus of the world. Medium-depth ground source heat pumps employing coaxial borehole heat exchangers have emerged as a pivotal choice for low-carbon heating. Heat transfer performance of coaxial borehole is vital for design, whose fundamental determinant is stratum thermal properties. However, direct measurement of these properties proves challenging for the complex stratum. Inversion methods, though avoiding this limitation, lack applicability to medium-depth boreholes. Therefore, a stratum thermophysical inversion algorithm was established based on an analytical model coupling the spatialtemporal dynamics of in-borehole fluid and stratum. Notable for its independence from initial values and the absence of parameter fitting, this algorithm offers a user-friendly solution. To validate the algorithm's accuracy and investigate heat extraction characteristics in Songliao Basin, an inaugural thermal response test at depth of 2500m was conducted in Shenyang, Liaoning. The maximum mean relative error is 9.4 % or the maximum absolute temperature error is +/- 0.94 degrees C. Correlation analysis suggests using the initial 0-13 h of data for volume heat capacity inversion and subsequent data for effective thermal conductivity inversion to enhance precision. Furthermore, a recommended minimum test duration of 80 h ensures robust results.
This paper presents a novel irradiance sensorless Maximum Power Point Tracking (MPPT) controller for photovoltaic (PV) systems using a Particle Swarm Optimization (PSO)-based Integral Backstepping (IBSC) and Immersion...
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This paper presents a novel irradiance sensorless Maximum Power Point Tracking (MPPT) controller for photovoltaic (PV) systems using a Particle Swarm Optimization (PSO)-based Integral Backstepping (IBSC) and Immersion & Invariance (I&I) algorithm. The proposed controller addresses the limitations of traditional and contemporary MPPT methods, such as the need for costly irradiance sensors and suboptimal performance under dynamic environmental conditions. The integration of a higher-order sliding mode differentiator (HOSMD) with the IBSC enhances transient response by completely eliminating overshoots, achieving a 0 % overshoot compared to 4.8 % with the conventional IBSC under standard test conditions. The system exhibits rapid tracking convergence with a significantly reduced tracking time of 0.4 ms, approximately seven times faster than the traditional Perturb and Observe (P&O) algorithm's 3 ms. Under real-world conditions, the proposed system's irradiance estimator maintains a mean absolute error below 15 W/m(2), with a maximum error of 69 W/m(2) at high irradiance levels. The system achieves an operating efficiency of 99.99 % with peak-to-peak power ripples of just 0.17 % under standard conditions, outperforming eight state-of-the-art MPPT techniques. This robust and efficient MPPT solution is validated through extensive simulations and real-climatic conditions. Additionally, real-climatic experimental implementations are carried out using Microcontroller-in-the-loop (MIL) integration. The acquired experimental results do not only corroborate the simulation outcomes but also endorses the reliability and practical robustness of the proposed MPPT controller.
Structural modal parameter identification is the initial step in modeling, monitoring and controlling dynamic systems, which can determine the accuracy of dynamics and control research. However, the uncertainty of dyn...
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Structural modal parameter identification is the initial step in modeling, monitoring and controlling dynamic systems, which can determine the accuracy of dynamics and control research. However, the uncertainty of dynamic systems is difficult to quantify, which will lead to deviations in structural modal parameter identification. Aiming to identify modal parameters under the influence of structural uncertainty parameters, this study proposed a novel interval-oriented eigensystem realization algorithm (ERA) and its modification with bounded uncertainties, which is particularly suitable for the case where structural uncertainty samples are scarce. The uncertain structures are quantified as interval uncertain parameters, which can reduce the need for quantification of uncertainty parameters without loss of accuracy. The first and second-order interval-oriented singular value decomposition (SVD) is developed, which is regarded as an important tool to solve the interval Hankel matrix. The conventional modal parameter identification method of ERA and ERA/DC are extended into the interval framework using first and second-order interval perturbation with a detailed derivation process, and the identified bounds of frequency and damping ratio can be accurately estimated using both interval-oriented ERA and ERA/DC in conjunction with first and second-order interval perturbation SVD. Finally, two numerical examples and one experimental verification are used to assess the proposed method.
Natural disasters, such as floods and fires, affect various regions of the world every year. One of the most critical aspects of disaster management and planning is facilitating the evacuation of people. Therefore, th...
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Natural disasters, such as floods and fires, affect various regions of the world every year. One of the most critical aspects of disaster management and planning is facilitating the evacuation of people. Therefore, this study develops a mathematical model for emergency evacuation, taking into account the constraints and limitations of transferring individuals to shelters. The model, called the maximal bus evacuation planning, considers constraints including road blockages, vehicle fuel, and passenger capacities. Given the Nondeterministic Polynomial-time hard complexity of this problem, a Hybrid Particle Swarm Optimization-Heuristic algorithm, which combines the Particle Swarm Optimization algorithm with a Heuristic algorithm, is used to solve the nonlinear model. Furthermore, we linearize the model and solve it using the developed Combinatorial Benders' Cuts approach in three versions. Numerical computations are examined under various scenarios, and the outputs of the Hybrid Particle Swarm Optimization - Heuristic algorithm reach suitable solutions within a short timeframe. Additionally, the results from solving the linearized model using the Combinatorial Benders' Cuts show that, in most cases, the execution time of the second version is better than the other versions.
The leaf area index (LAI) is an important parameter that can reflect the growth status of the winter wheat population. Using hyperspectral technology for rapid and non-destructive estimation of LAI can provide some re...
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The leaf area index (LAI) is an important parameter that can reflect the growth status of the winter wheat population. Using hyperspectral technology for rapid and non-destructive estimation of LAI can provide some reference for adjusting field management measures to promote healthy growth of winter wheat. Screening hyperspectral information is an important direction in hyperspectral research. Genetic algorithm (GA) is a commonly used variable selection method. However, traditional GA cannot effectively control the results of variable screening. Meanwhile, it is expected to further improve the variable screening effect by using more machine learning algorithms as fitness evaluation functions. In this regard, this study combined the exponential decay function in competitive adaptive reweighted sampling algorithm (CARS) and the GA, and combined multiple machine learning algorithms as fitness evaluation functions to propose the continuous reweighted decay genetic algorithm (CRDGA), to better screen the important bands of winter wheat LAI. Finally, hyperspectral estimation models for winter wheat LAI were constructed using multiple machine learning algorithms. The main results were as follows: Compared to the number of bands screened by CARS and GA, the number of bands screened by CRDGA was fewer, with 44, 32, 24, 10, 7, 19, and 197 bands, respectively. Using partial least squares regression, support vector regression (SVR), K-nearest neighbor regression (KNNR), and gaussian process regression (GPR) as fitness evaluation functions all had a faster convergence rate, other fitness evaluation functions all had a slower convergence rate. However, only SVR, KNNR, and GPR as fitness evaluation functions had fast running rates in both GA and CRDGA. When using the same fitness evaluation function to run GA and CRDGA to achieve the optimal fitness value, the fitness value obtained by the CRDGA algorithm was lower than that obtained by the GA algorithm. Among all the constructed
The use of CT scan to diagnose kidney stones is among the most accurate ways to confirm the presence of kidney stones in patients. The scan takes photographs inside the body using a computer and an X-ray. The present ...
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The use of CT scan to diagnose kidney stones is among the most accurate ways to confirm the presence of kidney stones in patients. The scan takes photographs inside the body using a computer and an X-ray. The present study proposes a new automatic methodology using an integrated Alexnet and ELM (Extreme Learning Machine) network to deliver more useful outcomes of detection for kidney stone. Afterward, the network is optimized on the basis of a newly improved version of firebug swarm optimization algorithm. The designed network is applied to the "CT Kidney Dataset", and its outcomes are then verified by some different advanced procedures. The final results indicated that the proposed approach has better performance than the other methods.
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