共查询到18条相似文献,搜索用时 62 毫秒
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电梯交通模式识别问题是电梯群控系统优化调度的基础.在电梯交通模式识别研究中,支持向量机应用较为广泛且识别效果较好,但仍存在模型参数难以确定的问题.为此,提出一种结合遗传算法和支持向量机的电梯交通流模式识别方法:利用遗传算法对支持向量机的关键参数对——惩罚因子C和核函数参数σ自动全局寻优,将最佳参数组合(C,σ)代入原始... 相似文献
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针对山西旅游需求统计数据时间短,影响因素复杂的特点,利用统计学习理论建立支持向量机(Support Vector Machine,SVM)的时间序列预测模型对山西的旅游需求进行了预测和对策分析.实验表明,支持向量机模型在旅游需求预测中有很大的应用潜力. 相似文献
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新型电梯群控系统交通模式识别方法 总被引:7,自引:0,他引:7
电梯交通模式识别是电梯群控调度的一个关键问题.针对实时变化的电梯交通流数据,提出一种新型的电梯系统交通模式识别方法.在不增加数据采集量的基础上,首先对基本交通信息进行预处理,再采用多值分类的支持向量机算法,对电梯群控系统建立交通模式分类器.建立的分类器可以根据交通流数据的变化,自适应地识别出建筑物内的最大客流层及次大客流层(厅堂除外).仿真结果表明,这种交通模式识别方法能较准确地辨识出各种交通流模式,并且通过对比试验,证明该算法的识别准确率优于人工神经网络算法,体现出较好的泛化能力,实用性强. 相似文献
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研究物流需求问题,物流受多种因素的综合影响,需求具有趋势性、较大波动性和随机性等变化特点,传统单一预测方法难以对其进行准确预测,为提高物流需求预测准确率,将灰色理论(GM)和支持向量机(SVM)相结合建立一种物流需求预测模型(GM-SVM)。GM-SVM首先采用灰色GM(1,1)预测模型动态预测物流需求变化趋势,然后运用SVM对GM(1,1)预测结果进行修正,以提高物流需求预测精度。采用具体物流需求实例对GM-SVM性能进行测试,实验结果表明,GM-SVM利用SVM和GM(1,1)的优势,达到优势互补,提高了物流需求的预测精度,更能全面描述物流需求的复杂变化规律。 相似文献
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为了提高物流需求预测精度,针对物流需求的复杂变化特性,提出一种蚁群算法ACO)优化最小二乘支持向量机的(LSSVM)的物流需求预测模型(ACO-LSSVM).首先对物流需求数据进行重构,然后采用LSSVMY刻画物流需求的复杂非线性变化特性,并通过ACO算法优化选择LSSVM参数,采用物流需求预测实例对ACO-LSSVM性能进行测试.结果表明,ACO-LSSVM提高了物流需求预测精度,是一种有效的物流需求预测方法. 相似文献
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鉴于灰色预测方法和支持向量机各自的优点,将灰色预测方法与支持向量机相结合,建立灰色支持向量机模型,并以极差替代收益的标准差度量波动率,运用新模型对深圳基金波动率进行实例分析。通过与v支持向量机的预测结果对比,发现所提出的模型适合于基金波动率的中短期预测。 相似文献
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This article presents a new algorithm for forecasting demand for perishable farm products, based on the support vector machine (SVM) method. Since SVMs have greater generalisation performance and guarantee global minima for given training data, it is believed that support vector regression will perform well for forecasting demand for perishable farm products. In order to improve forecasting precision (FP), this article quantifies the factors affecting the sales forecast of perishable farm products based on the fuzzy theory, which is suitable for real situations. Numerical experiments show that forecasting systems with SVMs and fuzzy theory outperform the radial basis function neural network, based on the criteria of day absolute error, relative mean error and FP. Since there is no structured way to choose the free parameters of SVMs, the variational range of free parameters and the effects of the parameters on prediction performance are discussed in this article. Analysis of experimental results proves that it is advantageous to apply SVMs forecasting system in perishable farm products demand forecasting. 相似文献
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Abstract: The relevance vector machine (RVM) is a Bayesian version of the support vector machine, which with a sparse model representation has appeared to be a powerful tool for time-series forecasting. The RVM has demonstrated better performance over other methods such as neural networks or autoregressive integrated moving average based models. This study proposes a hybrid model that combines wavelet-based feature extractions with RVM models to forecast stock indices. The time series of explanatory variables are decomposed using some wavelet bases and the extracted time-scale features serve as inputs of an RVM to perform the non-parametric regression and forecasting. Compared with traditional forecasting models, our proposed method performs best. The root-mean-squared forecasting errors are significantly reduced. 相似文献
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城市小时级需水量的改进型引力搜索算法--最小二乘支持向量机模型预测 总被引:1,自引:0,他引:1
本文研究利用最小二乘支持向量机(least squares support vector machine,LS-SVM)算法建立城市小时级需水量预测模型.采取精英策略,自适应的速度更新权重系数,同时引入粒子历史最优信息对引力搜索算法(gravitational search algorithm,GSA)进行了改进.最后采用改进型引力搜索算法(ameliorated gravitational search algorithm,AGSA)优化LS-SVM水量预测模型的正规化参数和核参数来提高模型的预测精度及预测速度.理论测试与实例分析表明,基于AGSA比基于GSA,遗传算法(genetic algorithms,GA)和粒子群优化算法(particle swarm optimization,PSO)的LS-SVM水量预测模型具有更好的预测精度,从而验证了基于AGSA的LS-SVM算法适用于小时级需水量预测问题,AGSA适用于多领域的模型参数的优化过程. 相似文献
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In recent years, Gaussian process (GP) models have been popularly studied to solve hard machine learning problems. The models are important due to their flexible non-parametric modeling abilities using Mercer kernels and the Bayesian framework for probabilistic inference. In this paper, we propose a sparse GP regression (GPR) model for tourism demand forecasting in Hong Kong. The sparsification procedure of the GPR model not only decreases the computational complexity but also improves the generalization ability. We experiment the proposed model with monthly demand data that are relevant to Hong Kong’s tourism industry, and compare the performance of the sparse GPR model with those of various kernel-based models to show its effectiveness. The proposed sparse GPR model shows that its forecasting capability outperforms those of the ARMA model and the two state-of-the-art SVM models. 相似文献
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为了提高基于最小二乘支持向量机的交通流预测模型的精度,提出一种新的改进引力搜索算法(TCK-AGSA)对其进行参数寻优。首先,基于Tent映射改进Kbest函数,使算法具有跳出局部最优的机制;然后,引入全局最优引导策略,使粒子加速朝向最优解移动;接着,将进化度因子和聚合度因子引入速度更新权重系数,使算法具有较强的自适应能力。针对12个基准函数的仿真结果表明,TCK-AGSA的性能优于GSA及其改进算法。最后,建立基于TCK-AGSA寻优的最小二乘支持向量机模型,并选取2016年贵州省高速公路真实交通流数据进行预测实验,结果表明该模型具有更好的预测精度、鲁棒性和泛化能力。 相似文献