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1.
针对水环境质量综合评价中指标权重确定方法的不足,利用学习向量量化(LVQ)神经网络具有的强大的非线性运算和相似特征聚类功能,提出一种基于学习向量量化(LVQ)神经网络的水质综合评价决策方法.将它应用于水质综合指标评价,为改进水质综合评价提供了一种简捷的分类评价方法.  相似文献   

2.
通过构建粗糙集BP神经网络模型,对影响房地产选址决策的指标进行约简,提取影响选址评价的主要指标因素用属性约简算法约简,将降维后的数据送入网络进行学习和训练,最后用训练好的的网络检验测试样本.模型使学习训练的速度和识别率提高了,为房地产企业在房地产选址决策中提供了一种更为有效和实用的新方法.  相似文献   

3.
基于BP神经网络的企业未来获利能力智能综合评价   总被引:3,自引:0,他引:3  
分析了相关分析——多指标综合评价法在确定企业未来获利能力方面的优点和不足 ;并在其基础上提出了基于 BP神经网络的多指标综合评价法 ;仿真试验证明了基于 BP神经网络的多指标综合评价法的有效性  相似文献   

4.
结合5种混凝土延性柱耗能器在低周期反复荷载作用下的试验数据研究,利用神经网络的工作原理,通过建立神经网络的输入层、隐含层、输出层,确定输入单元、输出单元和隐含层节点数,从而建立了BP神经网络的模型,并根据已有的部分试验数据数据.对网络进行训练,对各种混凝土延性柱耗能器骨架曲线进行了预测拟合,实现混凝土延性柱耗能器骨架曲线的数字化,使其成为具有分析和判断的拟合曲线功能,完整的描绘混凝土延性柱耗能器的骨架曲线,为后续混凝土延性柱耗能器性能研究的仿真模拟提供了可靠的数据模型.结果表明,这种方法是可行的.  相似文献   

5.
BP神经网络在企业经营绩效评价中的应用   总被引:4,自引:0,他引:4  
对企业经营绩效的评价主要采用线性和非线性两类评价模型,非线性评价模型能够更好地对经济现象进行仿真,评价结果客观、准确,更加具有实际参考价值。本文从考核投入产出效率的角度出发,选取基本财务指标构成评价体系,在此基础上,建立基于误差逆传播人工神经网络(BP神经网络)的高新技术企业绩效评价模型。以医药行业2003年度22家上市公司财务数据作为神经网络的训练和测试样本,将训练好的BP神经网络应用于企业绩效的当期评价和仿真预测,实证分析结果令人满意。  相似文献   

6.
针对人体健康评估所需参数多,专业性较强,家人对家庭卧床失能老人的健康状况难以准确判断等问题,与医院、养老机构和老年社区合作,提出一种基于遗传神经网络的家庭简单健康评估方法.首先挑选出家庭易测且能反映健康状况的5项生理参数作为特征向量,并对应设置3个健康等级,然后利用遗传神经网络建立生理参数与健康等级的映射关系,最后与一般神经网络进行对比.仿真结果表明,遗传神经网络模型预测误差更小,准确率更高,验证了方法在老人健康评估中的可行性.  相似文献   

7.
利用模糊数学和神经网络方法建立对运动员进行评价的模糊网络模型,采用NBA流行的各评价指标作为其输入,模糊综合评价结果作为输出。样本数据采用2003~2004赛季NBA各单项50强的常规赛数据,分别用BP网络和RBF网络,建立分析系统,比较结果证明RBF网络仿真效果最好,完全可以实用,该模型也可以用在其它综合评价系统中。  相似文献   

8.
根据军队知识管理的特点,构建了军队知识管理水平评价指标体系,指标体系从组织结构、人力、技术及知识系统4个一级指标和12个二级指标体系,运用四层模糊神经网络确定模糊综合评价中的权重值,同时采用改进的反向传播算法,用样本对网络进行训练,逐步修正网络的连接权值,使权重值更符合实际情况,最后用训练好的样本对六个单位的知识管理进行评估,结果表明,训练好的模糊神经网络可以对军队的知识管理进行评估,并得到很好的结果。  相似文献   

9.
本文提出了一种基于神经网络与群智能技术的多代理人决策模型.该决策模型以神经网络作为决策控制器,神经网络的输入层是代理人的历史行为策略,输出层决定了代理人的当前策略,神经网络的权重通过群智能优化技术进行训练.权重值的更新过程刻画了代理人行为策略的动态变化过程.仿真实验表明该决策模型具有自适应学习的能力,并能克服代理人之间的冲突取得Pareto最优.  相似文献   

10.
信用评价是选择武器装备承制商的重要手段.以国标为基础,结合承制商具体情况确定了信用评价指标体系.分析了传统信用评价方法的不足,对经典BP神经网络的误差函数进行优化,优化后的网络模型收敛速度更快,预测精度更高.构建BP神经网络武器装备承制商信用评价模型,仿真实验表明武器装备承制商信用评价可以选用BP神经网络模型.  相似文献   

11.
According to the characteristics of wood dyeing, we propose a predictive model of pigment formula for wood dyeing based on Radial Basis Function (RBF) neural network. In practical application, however, it is found that the number of neurons in the hidden layer of RBF neural network is difficult to determine. In general, we need to test several times according to experience and prior knowledge, which is lack of a strict design procedure on theoretical basis. And we also don’t know whether the RBF neural network is convergent. This paper proposes a peak density function to determine the number of neurons in the hidden layer. In contrast to existing approaches, the centers and the widths of the radial basis function are initialized by extracting the features of samples. So the uncertainty caused by random number when initializing the training parameters and the topology of RBF neural network is eliminated. The average relative error of the original RBF neural network is 1.55% in 158 epochs. However, the average relative error of the RBF neural network which is improved by peak density function is only 0.62% in 50 epochs. Therefore, the convergence rate and approximation precision of the RBF neural network are improved significantly.  相似文献   

12.
Selecting the optimal topology of a neural network for a particular application is a difficult task. In the case of recurrent neural networks, most methods only induce topologies in which their neurons are fully connected. In this paper, we present a genetic algorithm capable of obtaining not only the optimal topology of a recurrent neural network but also the least number of connections necessary. Finally, this genetic algorithm is applied to a problem of grammatical inference using neural networks, with very good results.  相似文献   

13.
§1Introduction Inrecentyearstherehasbeengrowinginterestintheproblemofneuralnetworkand relatedapproximation,manyimportantresultsareobtained.Becauseofitsabilityof parallelcomputationinlargescaleandofperfectself-adaptingandapproximation,the neuralnetworkhasbeenwidelyapplied.Theapproximationabilityoftheneuralnetwork dependsonitstopologicalstructure.LetRsbeans-dimensionalEuclidSpaceand(x)isa realfunctiondefinedonRs.When(x)isanexcitationfunctionandx∈Rsisaninput vector,thesimpleneuralnetwork…  相似文献   

14.
In this paper, we propose an unsupervised context-sensitive technique for change-detection in multitemporal remote sensing images. Here a modified self-organizing feature map neural network is used. Each spatial position of the input image corresponds to a neuron in the output layer and the number of neurons in the input layer is equal to the number of features of the input patterns. The network is updated depending on some threshold value and when the network converges, status of output neurons depict a change-detection map. To select a suitable threshold of the network, a correlation based and an energy based criteria are suggested. The proposed change-detection technique is unsupervised and distribution free. Experimental results, carried out on two multispectral and multitemporal remote sensing images, confirm the effectiveness of the proposed approach.  相似文献   

15.
The probabilistic neural network (PNN) is a neural network architecture that approximates the functionality of the Bayesian classifier, the optimal classifier. Designing the optimal Bayesian classifier is infeasible in practice, since the distributions of data belonging to each class are unknown. PNN is an approximation of the Bayesian classifier by approximating these distributions using the Parzen window approach. One of the criticisms of the PNN classifier is that, at times, it uses a lot of training data for its design. Furthermore, the PNN classifier requires that the user specifies certain network parameters, called the smoothing (spread) parameters, in order to approximate the distributions of the class data, which is not an easy task. A number of approaches have been reported in the literature for addressing both of these issues (i.e., reducing the number of training data needed for the building of the PNN model and producing good values for the smoothing parameters). In this effort, genetic algorithms are used to achieve both goals at once, and some promising results are reported.  相似文献   

16.
Data classification is an important area of data mining. Several well known techniques such as decision tree, neural network, etc. are available for this task. In this paper we propose a Kalman particle swarm optimized (KPSO) polynomial equation for classification for several well known data sets. Our proposed method is derived from some of the findings of the valuable information like number of terms, number and combination of features in each term, degree of the polynomial equation etc. of our earlier work on data classification using polynomial neural network. The KPSO optimizes these polynomial equations with a faster convergence speed unlike PSO. The polynomial equation that gives the best performance is considered as the model for classification. Our simulation result shows that the proposed approach is able to give competitive classification accuracy compared to PNN in many datasets.  相似文献   

17.
A finite impulse response neural network, with tap delay lines after each neuron in hidden layer, is used. Genetic algorithm with arithmetic decimal crossover and Roulette selection with normal probability mutation method with linear combination rule is used for optimization of FIR neural network. The method is applied for prediction of several important and benchmarks chaotic time series such as: geomagnetic activity index natural time series and famous Mackey–Glass time series. The results of simulations shows that applying dynamic neural models for modeling of highly nonlinear chaotic systems is more satisfactory with respect to feed forward neural networks. Likewise, global optimization method such as genetic algorithm is more efficient in comparison of nonlinear gradient based optimization methods like momentum term, conjugate gradient.  相似文献   

18.
机队作为航空公司运输能力的关键,其安全性与可靠性直接影响到航空公司的经济效益.根据航空公司机队可靠性统计和数据采集方式以及实际应用情况,建立了航空公司机队可靠性评价指标体系.鉴于机队可靠性受多种复杂因素影响及各指标体系非线性等特点,结合人工神经网络基本原理和特性,提出了BP神经网络机队可靠性评价模型.最后应用该模型对航空公司机队可靠性进行了实例分析,得出了评价等级.结果表明,基于BP神经网络机队可靠性评价模型是可行的,该方法能够实现动态的评价,对提高航空公司机队可靠性评价技术水平具有现实的意义.  相似文献   

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