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61.
The uncertainty associated with modeling and performance prediction of solar photovoltaic systems could be easily and efficiently solved by artificial intelligence techniques. During the past decade of 2009 to 2019, artificial neural network (ANN), fuzzy logic (FL), genetic algorithm (GA) and their hybrid models are found potential artificial intelligence tools for performance prediction and modeling of solar photovoltaic systems. In addition, during this decade there is no extensive review on applicability of ANN, FL, GA and their hybrid models for performance prediction and modeling of solar photovoltaic systems. Therefore, this article focuses on extensive review on design, modeling, maximum power point tracking, fault detection and output power/efficiency prediction of solar photovoltaic systems using artificial intelligence techniques of the ANN, FL, GA and their hybrid models. In addition, the selected articles on the solar radiation prediction using ANN, FL, GA and their hybrid models are also summarized. Total of 122 articles are reviewed and summarized in the present review for the period of 2009 to 2019 with 90 articles in the field of {ANN, FL, GA and their hybrid models} + solar photovoltaic systems and 32 articles in the field of {ANN, FL, GA and their hybrid models} + solar radiation. The review shows the suitability and reliability of ANN, FL, GA and hybrid models for accurate prediction of the solar radiation and the performance characteristics of solar photovoltaic systems. In addition, this review presents the guidance for the researchers and engineers in the field of solar photovoltaic systems to select the suitable prediction tool for enhancement of the performance characteristics of the solar photovoltaic systems and the utilization of the available solar radiation.  相似文献   
62.
People in the Middle East are facing the problem of freshwater shortages. This problem is more intense for a remote region, which has no access to the power grid. The use of seawater desalination technology integrated with the generated energy unit by renewable energy sources could help overcome this problem. In this study, we refer a seawater reverse osmosis desalination (SWROD) plant with a capacity of 1.5 m3/h used on Larak Island, Iran. Moreover, for producing fresh water and meet the load demand of the SWROD plant, three different stand‐alone hybrid renewable energy systems (SAHRES), namely wind turbine (WT)/photovoltaic (PV)/battery bank storage (BBS), PV/BBS, and WT/BBS are modeled and investigated. The optimization problem was coded in MATLAB software. Furthermore, the optimized results were obtained by the division algorithm (DA). The DA has been developed to solve the sizing problem of three SAHRES configurations by considering the object function's constraints. These results show that this improved algorithm has been simpler, more precise, faster, and more flexible than a genetic algorithm (GA) in solving problems. Moreover, the minimum total life cycle cost (TLCC = 243 763$), with minimum loss of power supply probability (LPSP = 0%) and maximum reliability, was related to the WT/PV/BBS configuration. WT/PV/BBS is also the best configuration to use less battery as a backup unit (69 units). The batteries in this configuration have a longer life cycle (maximum average of annual battery charge level) than two other configurations (93.86%). Moreover, the optimized results have shown that utilizing the configuration of WT/PV/BBS could lead to attaining a cost‐effective and green (without environmental pollution) SAHRES, with high reliability for remote areas, with appropriate potential of wind and solar irradiance.  相似文献   
63.
It is essential to develop an accurate model of proton exchange membrane fuel cell (PEMFC) for a reliable operation and analysis, in which unknown parameters usually need to be determined. The inherent nonlinear, strong coupling, and diversification of PEMFC model seriously hinder traditional methods to identify the parameters. For the sake of overcoming these thorny obstacles, Levenberg-Marquardt backpropagation (LMBP) algorithm based on artificial neural networks (ANNs) is proposed for PEMFC parameter identification. Furthermore, the performance of LMBP is thoroughly evaluated and compared with four typical meta-heuristic algorithms under three cases. Simulation results indicate that LMBP performs a higher accuracy and faster speed for parameter identification. In particular, accuracy and convergence speed can achieve as much as 99.8% and 95.9% growth via LMBP, respectively.  相似文献   
64.
摘要:轧制力预报一直是热连轧过程控制模型的核心,浅层神经网络对复杂函数的表示能力有限,而深度学习模型通过学习一种深层非线性网络结构,实现复杂函数逼近。利用深度学习框架TensorFlow,构建了一种深度前馈神经网络轧制力模型,采用BP算法计算网络损失函数的梯度,运用融入Mini batch策略的Adam优化算法进行参数寻优,采用Early stopping、参数惩罚和Dropout正则化策略提高模型的泛化能力。基于上述建模策略,针对宝钢1880热连轧精轧机组的大量轧制历史数据进行了建模实验,对比分析了4种不同结构的前馈网络预测精度。结果表明,相比于传统SIMS轧制力模型,深度神经网络可实现轧制力的高精度预测,针对所有机架的预测精度平均提升21.11%。  相似文献   
65.
In this paper, we present a new bilevel model for a biomedical supply chain network with capacity and budget constraint due to the protection and interdiction operations. The components considered in this model are biomedical devices, distribution centers (DCs), medical suppliers (MSs), and hospitals and patients as the demand points. On the other hand, two levels of decisions in the network planning is suggested: (1) the defender’s decision about protection operations of MSs and DCs, the assignment of clients to the DCs, and quantity of products shipped to DCs from MSs to minimize the demand-weighted traveling costs and transport costs and (2) the attacker’s decision about interdiction operations of MSs and DCs to maximize the capacity or service reduction and losses. Because of nondeterministic polynomial time (NP)-hardness of the problem under consideration, an efficient and fast approach based on a genetic algorithm and a fast branch and cut method (GA–FBC) was developed to solve the proposed model. Also, the efficiency via the comparison of results with the genetic algorithm based on CPLEX (GA-CPLEX) and decomposition method (DM) is investigated. In order to assess the performance of the presented GA–FBC, a set of 27 instances of the problem is used. Comprehensive analysis indicates that the proposed approach significantly solves the problem. In addition, the benefits and advantages of preference with running times and its accuracy is shown numerically. Simulation results clearly demonstrate that the defender’s objective effectively reduced and CPU time also within the large-sized instances of the problem in comparison with the GA-CPLEX and DM.  相似文献   
66.
This paper proposes a robust optimization approach for multiple damage identification of plate-like structures. Different from traditional particle swarm optimizations (PSOs), a combined PSO and niche technique (NPSO) is proposed to solve multimodal optimization problems, with the full consideration of subswarm creation, merging and absorbing mechanism. As a hypersensitive parameter to damage, the curvature mode shape is adopted to construct the objective function. Case studies are conducted to investigate the effectiveness and robustness of the algorithm on multi-damage identification. Simulation results show that the proposed algorithm exhibits robust search performance on identifying damage locations accurately with good convergence behavior. It is hoped that this study can provide guidance on robust damage detection, especially when the structure is subject to multiple damages and external disturbances.  相似文献   
67.
This paper attempted to show the application of particle swarm optimization in the prediction of the compressive strength of cement sandy soil from the curing period, porosity of sample and percentage of cement. The results of the study show that the unconfined compressive strength of the cement stabilized sandy soil increases with an increasing cement content curing time period. Moreover the compressive strength decreases with an increasing porosity. The compressive strength improvement due to cement treatment has a larger increase in samples with less porosity. In addition, particle swarm optimization algorithm is and accurate technique in estimation of compressive strength of cement stabilized sandy soil. In order to compare of existing correlations, a total number of 100 unconfined compressive tests and 15 scanning electron microscope tests have been conducted on cemented Babolsar sand. It can be concluded that compared to existing correlations models, particle swarm optimization algorithm models give more reliable prediction about compressive strength of cement satblized sandy soil. Moreover, the sensitivity analysis of the polynomial model shows that cement content and porosity have significant impact on predicting unconfined compressive strength.  相似文献   
68.
马尔可夫聚类算法(MCL)是在大规模生物网络中寻找模块的一个有效方法,能够挖掘网络结构和功能影响力较大的模块。算法涉及到大规模矩阵计算,因此复杂度可达立方阶次。针对复杂度高的问题,提出了基于消息传递接口(MPI)的并行化马尔可夫聚类算法以提高算法的计算性能。首先,生物网络转化成邻接矩阵;然后,根据算法的特性,按照矩阵的规模判断并重新生成新矩阵以处理非平方倍数矩阵的计算;其次,并行计算通过按块分配的方式能够有效地实现任意规模矩阵的运算;最后,循环并行计算直至收敛,得到网络聚类结果。通过模拟网络和真实生物网络数据集的实验结果表明,与全块集体式通信(FCC)并行方法相比,平均并行效率提升了10个百分点以上,因此可以将该优化算法应用在不同类型的大规模生物网络中。  相似文献   
69.
在过去几十年里,许多多目标进化算法被广泛应用于解决多目标优化问题,其中一种比较流行的多目标进化算法是基于分解的多目标进化算法(MOEA/D)。花朵授粉算法是一种启发式优化算法,但迄今为止,花朵授粉算法在基于分解的多目标进化算法领域的研究还非常少。本文在基于分解的多目标进化算法的框架下,将花朵授粉算法拓展至多目标优化领域,提出一种基于分解的多目标花朵授粉算法(MOFPA/D)。此外,为了保证非支配解的多样性,本文提出一种基于网格的目标空间分割法,该方法从找到的Pareto最优解集中筛选出一定数量且分布均匀的Pareto最优解。实验结果表明,基于分解的多目标花朵授粉算法在收敛性与多样性方面均优于基于分解的多目标进化算法。  相似文献   
70.
目的 近年来,随着我国遥感技术的快速发展,遥感数据呈现出大数据的特点,遥感数据的时效性增强,针对新环境下遥感算法编程语言众多,程序运行和部署环境需求多样,程序的集成和部署困难的问题,提出了一种遥感算法程序快速封装与Docker容器化系统集成架构。方法 该系统架构主要包括:1)遥感算法程序的镜像自动化封装制作;2)镜像的分发管理,达到算法程序镜像的共享;3)遥感信息产品生产流程的容器化编排服务,将相关联的算法程序镜像串联,以满足特定遥感信息产品的生产;4)容器的调度运行,调用镜像,实现特定遥感产品的容器化运行。本文在上述容器化系统集成架构下,以Landsat5数据的NDVI、NDWI信息产品的生产作为容器化生产实例,并同物理机、KVM (kernel-based virtual machine)虚拟机在运行时间、内存占用量、部署效率等性能进行了对比。结果 Docker容器虚拟化环境下的产品生产和物理机环境下在运行时间和内存占用量上几无差别,优于KVM虚拟机。Docker容器虚拟化环境和KVM虚拟机环境下在部署上能够节省大量时间,相比于物理机环境能够提高部署效率。结论 容器化的系统集成方式能够有效解决遥感算法程序集成和部署困难的问题,有利于遥感算法程序的复用和流程的共享,提高系统集成效率,具备较强的遥感数据实时快速处理能力。  相似文献   
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