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11.
Great efforts have been made to resolve the serious environmental pollution and inevitable declining of energy resources. A review of Chinese fuel reserves and engine technology showed that compressed natural gas (CNG)/diesel dual fuel engine (DFE) was one of the best solutions for the above problems at present. In order to study and improve the emission performance of CNG/diesel DFE, an emission model for DFE based on radial basis function (RBF) neural network was developed which was a black-box input-output training data model not require priori knowledge. The RBF centers and the connected weights could be selected automatically according to the distribution of the training data in input-output space and the given approximating error. Studies showed that the predicted results accorded well with the experimental data over a large range of operating conditions from low load to high load. The developed emissions model based on the RBF neural network could be used to successfully predict and optimize the emissions performance of DFE. And the effect of the DFE main performance parameters, such as rotation speed, load, pilot quantity and injection timing, were also predicted by means of this model. In resume, an emission prediction model for CNG/diesel DFE based on RBF neural network was built for analyzing the effect of the main performance parameters on the CO, NOx emissions of DFE. The predicted results agreed quite well with the traditional emissions model, which indicated that the model had certain application value, although it still has some limitations, because of its high dependence on the quantity of the experimental sample data.  相似文献   
12.
The solid oxide fuel cell (SOFC) is a nonlinear system that is hard to model by conventional methods. So far,most existing models are based on conversion laws,which are too complicated to be applied to design a control system. To facilitate a valid control strategy design,this paper tries to avoid the internal complexities and presents a modelling study of SOFC per-formance by using a radial basis function (RBF) neural network based on a genetic algorithm (GA). During the process of mod-elling,the GA aims to optimize the parameters of RBF neural networks and the optimum values are regarded as the initial values of the RBF neural network parameters. The validity and accuracy of modelling are tested by simulations,whose results reveal that it is feasible to establish the model of SOFC stack by using RBF neural networks identification based on the GA. Furthermore,it is possible to design an online controller of a SOFC stack based on this GA-RBF neural network identification model.  相似文献   
13.
针对特征信号淹没于噪声信号的情况,采用Morlet小波分析实现了对原始电流特征信号的降噪.同时,采用基于RBF神经网络的最优化插值与具有频谱细化特性的CZT分析,提升了频谱分辨率,充分展现了发生故障时电流特征信号的频谱细节,为电机故障诊断系统提供了可靠的诊断依据.建立了基于改进型BP神经网络的电机故障模糊诊断系统,抽象出了偏心故障的诊断规则.实测结果表明,该系统能够可靠地诊断电机的偏心故障.  相似文献   
14.
在有限差分和径向基函数的基础上,分别利用无网格法中的Kansa方法和特解方法(MPS)来求解一类热传导方程,并对所求结果进行比较与分析.同时本文还给出了一个例子来说明这两种方法的运算情况,从而对这两种方法进行进一步的比较,以确定哪种方法的精确性更好.  相似文献   
15.
提出了一种基于RBF神经网络的CaO—CaF2-SiO2渣系ZGMn13堆焊焊条配方优化设计方法.利用实验采集的数据对网络进行训练,以加工硬化后的硬度为优化目标,得到最优的焊条配方.实验结果表明:优化后熔敷金属的动载加工硬化性能和静载加工硬化性能良好。  相似文献   
16.
利用RBF网络,引用美国教师评价指标,从教师的责任心、知识结构、管理能力、质疑批判能力、科研能力和合作沟通能力六个方面,建立了新的教师评价体系,结果表明较好地反映了教师的实际能力。  相似文献   
17.
[目的/意义] 采用企业专利大数据,构造高维云模型,预测企业成长性。[方法/过程] 选取中国股票市场创业板公司为研究对象,依据企业专利聚类结果,用逆向云模型多步式算法生成专利的云模型改造神经网络神经元,构造云模型;用因子分析计算企业的成长性并通过聚类分析分成4类;用云模型补充不平衡数据。[结果/结论] 研究表明,高维云神经网络能很好预测企业的成长性,准确性和稳定性得到提高,同时也表明企业专利对其成长性有重要作用。企业专利对成长性的影响是复杂的:专利同族数、发明专利占比、专利权利要求数对企业的成长性促进作用,而单纯专利数量有负面的影响。  相似文献   
18.
基于径向基神经网络的数字馆藏质量评价研究   总被引:1,自引:0,他引:1  
根据径向基神经网络的自组织、自学习和自适应等特性,提出了基于径向基神经网络的数字馆藏质量评价方法,建立了评价模型,运用该模型对山东省烟台和威海地区的5所高校图书馆的数字馆藏进行了质量评价.通过MATLAB仿真试验结果分析,证明了其可行性和有效性.  相似文献   
19.
根据互信息、RBF神经网络和关联规则原理,提出了一种抽取WEB文本分类规则的新方法。先根据互信息选择和各类相关程度大的若干词条,然后采用RBF神经网络方法对选择的特征进行进一步提取,得到维数较小的文本特征向量空间。之后再根据挖掘出的关联规则获取WEB文本分类规则,建立文本分类器,在保证了分类精度的前提下抽取出利于理解的文本分类规则。  相似文献   
20.
A closed-chain robot has several advantages over an open-chain robot, such as high mechanical rigidity, high payload, high precision. Accurate trajectory control of a robot is essential in practical use. This paper presents an adaptive proportional integral differential (PID) control algorithm based on radial basis function (RBF) neural network for trajectory tracking of a two-degree-of-freedom (2-DOF) closed-chain robot. In this scheme, an RBF neural network is used to approximate the unknown nonlinear dynamics of the robot, at the same time, the PID parameters can be adjusted online and the high precision can be obtained. Simulation results show that the control algorithm accurately tracks a 2-DOF closed-chain robot trajectories. The results also indicate that the system robustness and tracking performance are superior to the classic PID method.  相似文献   
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