In this paper, we propose a multidimensional version of recurrent least squares support vector machines (MDRLS- SVM) to solve the problem about the prediction of chaotic system. To acquire better prediction performa...In this paper, we propose a multidimensional version of recurrent least squares support vector machines (MDRLS- SVM) to solve the problem about the prediction of chaotic system. To acquire better prediction performance, the high-dimensional space, which provides more information on the system than the scalar time series, is first reconstructed utilizing Takens's embedding theorem. Then the MDRLS-SVM instead of traditional RLS-SVM is used in the high- dimensional space, and the prediction performance can be improved from the point of view of reconstructed embedding phase space. In addition, the MDRLS-SVM algorithm is analysed in the context of noise, and we also find that the MDRLS-SVM has lower sensitivity to noise than the RLS-SVM.展开更多
Coal mines require various kinds of machinery. The fault diagnosis of this equipment has a great impact on mine production. The problem of incorrect classification of noisy data by traditional support vector machines ...Coal mines require various kinds of machinery. The fault diagnosis of this equipment has a great impact on mine production. The problem of incorrect classification of noisy data by traditional support vector machines is addressed by a proposed Probability Least Squares Support Vector Classification Machine (PLSSVCM). Samples that cannot be definitely determined as belonging to one class will be assigned to a class by the PLSSVCM based on a probability value. This gives the classification results both a qualitative explanation and a quantitative evaluation. Simulation results of a fault diagnosis show that the correct rate of the PLSSVCM is 100%. Even though samples are noisy, the PLSSVCM still can effectively realize multi-class fault diagnosis of a roller bearing. The generalization property of the PLSSVCM is better than that of a neural network and a LSSVCM.展开更多
Least squares support vector machine (LS-SVM) is applied in gas path fault diagnosis for aero engines. Firstly, the deviation data of engine cruise are analyzed. Then, model selection is conducted using pattern sear...Least squares support vector machine (LS-SVM) is applied in gas path fault diagnosis for aero engines. Firstly, the deviation data of engine cruise are analyzed. Then, model selection is conducted using pattern search method. Finally, by decoding aircraft communication addressing and reporting system (ACARS) report, a real-time cruise data set is acquired, and the diagnosis model is adopted to process data. In contrast to the radial basis function (RBF) neutral network, LS-SVM is more suitable for real-time diagnosis of gas turbine engine.展开更多
In order to improve the firing efficiency of projectiles,it is required to use the universal firing table for gun weapon system equipped with a variety of projectiles.Moreover,the foundation of sharing the universal f...In order to improve the firing efficiency of projectiles,it is required to use the universal firing table for gun weapon system equipped with a variety of projectiles.Moreover,the foundation of sharing the universal firing table is the ballistic matching for two types of projectiles.Therefore,a method is proposed in the process of designing new type of projectile.The least squares support vector machine is utilized to build the ballistic trajectory model of the original projectile,thus it is viable to compare the two trajectories.Then the particle swarm optimization is applied to find the combination of trajectory parameters which meet the criterion of ballistic matching best.Finally,examples show the proposed method is valid and feasible.展开更多
A simple and effective mechanism is proposed to realize the parsimoniousness of the online least squares support vector regression (LS-SVR), and the approach is called the OPLS-SVR for short. Hence, the response tim...A simple and effective mechanism is proposed to realize the parsimoniousness of the online least squares support vector regression (LS-SVR), and the approach is called the OPLS-SVR for short. Hence, the response time is curtailed. Besides, an OPLS-SVR based analytical redundancy technique is presented to cope with the sensor failure and drift problems to guarantee that the provided signals for the aeroengine controller are correct and acceptable. Experiments on the sensor failure and drift show the effectiveness and the validity of the proposed analytical redundancy.展开更多
A thrust estimator with high precision and excellent real-time performance is needed to mitigate perfor- mance deterioration for future aero-engines. A weight least squares support vector regression is proposed using ...A thrust estimator with high precision and excellent real-time performance is needed to mitigate perfor- mance deterioration for future aero-engines. A weight least squares support vector regression is proposed using a novel weighting strategy. Then a thrust estimator based on the proposed regression is designed for the perfor- mance deterioration. Compared with the existing weighting strategy, the novel one not only satisfies the require- ment of precision but also enhances the real-time performance. Finally, numerical experiments demonstrate the effectiveness and feasibility of the proposed weighted least squares support vector regression for thrust estimator. Key words : intelligent engine control; least squares ; support vector machine ; performance deterioration展开更多
In order to realize direct thrust control instead of conventional sensors-based control for aero-engine, a thrust estimator with high accuracy is designed by using the boosting technique to improve the performance of ...In order to realize direct thrust control instead of conventional sensors-based control for aero-engine, a thrust estimator with high accuracy is designed by using the boosting technique to improve the performance of least squares support vector regression (LSSVR). There exist two distinct features compared with the conven- tional boosting technique: (1) Sampling without replacement is used to avoid numerical instability for modeling LSSVR. (2) To realize the sparseness of LSSVR and reduce the computational complexity, only a subset of the training samples is used to construct LSSVR. Thus, this boosting method for LSSVR is called the boosting sparse LSSVR (BSLSSVR). Finally, simulation results show that BSLSSVR-based thrust estimator can satisfy the requirement of direct thrust control, i.e. , maximum absolute value of relative error of thrust estimation is not more than 5‰.展开更多
针对桥梁挠度监测中温度效应的分离问题,根据桥梁挠度的组分特性,利用最小二乘支持向量机(leastsquare support vector machines,LS-SVM)模型,提出桥梁挠度监测中精确分离温度效应的方法。温度和挠度温度效应具有确定的非线性关系。应用...针对桥梁挠度监测中温度效应的分离问题,根据桥梁挠度的组分特性,利用最小二乘支持向量机(leastsquare support vector machines,LS-SVM)模型,提出桥梁挠度监测中精确分离温度效应的方法。温度和挠度温度效应具有确定的非线性关系。应用LS-SVM的逼近能力,将温度作为输入、挠度温度效应作为输出,建立温度和挠度温度效应的精确定量关系,在已知温度变化的情况下获取挠度温度效应的变化值,从而实现挠度温度效应准确分离。计算及分析结果表明,该方法能有效分离挠度监测信号中的温度效应,结合滤波方法,亦可有效分离出长期挠度,为结构的损伤识别提供了有效的数学手段和依据。展开更多
在电池管理系统中为了使荷电状态量SOC(state of charge)估计精确,提出以遗传算法优化最小二乘支持向量机(LS-SVM)的方法对电池的SOC进行预测的模型。在电池变流情况下对SOC进行研究,以标准工况下的实验数据作为样本,以电池的电流、电...在电池管理系统中为了使荷电状态量SOC(state of charge)估计精确,提出以遗传算法优化最小二乘支持向量机(LS-SVM)的方法对电池的SOC进行预测的模型。在电池变流情况下对SOC进行研究,以标准工况下的实验数据作为样本,以电池的电流、电压及温度作为训练模型的输入,SOC作为输出建立模型,使之能很好地适用于混合动力汽车用电池在变电流状态下的实时SOC估计。研究结果表明:该预测模型预测精度高,其最大相对误差小于3%,平均相对误差小于2%,且与神经网络预测结果相比具有更强的实用性。展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 90207012).
文摘In this paper, we propose a multidimensional version of recurrent least squares support vector machines (MDRLS- SVM) to solve the problem about the prediction of chaotic system. To acquire better prediction performance, the high-dimensional space, which provides more information on the system than the scalar time series, is first reconstructed utilizing Takens's embedding theorem. Then the MDRLS-SVM instead of traditional RLS-SVM is used in the high- dimensional space, and the prediction performance can be improved from the point of view of reconstructed embedding phase space. In addition, the MDRLS-SVM algorithm is analysed in the context of noise, and we also find that the MDRLS-SVM has lower sensitivity to noise than the RLS-SVM.
基金supported by the Program for New Century Excellent Talents in University (NoNCET- 08-0836)the National Natural Science Foundation of China (Nos60804022, 60974050 and 61072094)+1 种基金the Fok Ying-Tung Education Foundation for Young Teachers (No121066)by the Natural Science Foundation of Jiangsu Province (No.BK2008126)
文摘Coal mines require various kinds of machinery. The fault diagnosis of this equipment has a great impact on mine production. The problem of incorrect classification of noisy data by traditional support vector machines is addressed by a proposed Probability Least Squares Support Vector Classification Machine (PLSSVCM). Samples that cannot be definitely determined as belonging to one class will be assigned to a class by the PLSSVCM based on a probability value. This gives the classification results both a qualitative explanation and a quantitative evaluation. Simulation results of a fault diagnosis show that the correct rate of the PLSSVCM is 100%. Even though samples are noisy, the PLSSVCM still can effectively realize multi-class fault diagnosis of a roller bearing. The generalization property of the PLSSVCM is better than that of a neural network and a LSSVCM.
基金The National High Technology Research and Development Program of China (No.2006AA12A108)
文摘Least squares support vector machine (LS-SVM) is applied in gas path fault diagnosis for aero engines. Firstly, the deviation data of engine cruise are analyzed. Then, model selection is conducted using pattern search method. Finally, by decoding aircraft communication addressing and reporting system (ACARS) report, a real-time cruise data set is acquired, and the diagnosis model is adopted to process data. In contrast to the radial basis function (RBF) neutral network, LS-SVM is more suitable for real-time diagnosis of gas turbine engine.
基金supported by the National Natural Science Foundation of China(No.51006052)
文摘In order to improve the firing efficiency of projectiles,it is required to use the universal firing table for gun weapon system equipped with a variety of projectiles.Moreover,the foundation of sharing the universal firing table is the ballistic matching for two types of projectiles.Therefore,a method is proposed in the process of designing new type of projectile.The least squares support vector machine is utilized to build the ballistic trajectory model of the original projectile,thus it is viable to compare the two trajectories.Then the particle swarm optimization is applied to find the combination of trajectory parameters which meet the criterion of ballistic matching best.Finally,examples show the proposed method is valid and feasible.
基金Supported by the National Natural Science Foundation of China(50576033)the Aeronautical ScienceFoundation of China(04C52019)~~
文摘A simple and effective mechanism is proposed to realize the parsimoniousness of the online least squares support vector regression (LS-SVR), and the approach is called the OPLS-SVR for short. Hence, the response time is curtailed. Besides, an OPLS-SVR based analytical redundancy technique is presented to cope with the sensor failure and drift problems to guarantee that the provided signals for the aeroengine controller are correct and acceptable. Experiments on the sensor failure and drift show the effectiveness and the validity of the proposed analytical redundancy.
基金Supported by the National Natural Science Foundation of China(51006052)the Nanjing University of Science and Technology Outstanding Scholar Supporting Program~~
文摘A thrust estimator with high precision and excellent real-time performance is needed to mitigate perfor- mance deterioration for future aero-engines. A weight least squares support vector regression is proposed using a novel weighting strategy. Then a thrust estimator based on the proposed regression is designed for the perfor- mance deterioration. Compared with the existing weighting strategy, the novel one not only satisfies the require- ment of precision but also enhances the real-time performance. Finally, numerical experiments demonstrate the effectiveness and feasibility of the proposed weighted least squares support vector regression for thrust estimator. Key words : intelligent engine control; least squares ; support vector machine ; performance deterioration
基金Supported by the National Natural Science Foundation of China(50576033)the Aeronautical Science Foundation of China(04C52019)~~
文摘In order to realize direct thrust control instead of conventional sensors-based control for aero-engine, a thrust estimator with high accuracy is designed by using the boosting technique to improve the performance of least squares support vector regression (LSSVR). There exist two distinct features compared with the conven- tional boosting technique: (1) Sampling without replacement is used to avoid numerical instability for modeling LSSVR. (2) To realize the sparseness of LSSVR and reduce the computational complexity, only a subset of the training samples is used to construct LSSVR. Thus, this boosting method for LSSVR is called the boosting sparse LSSVR (BSLSSVR). Finally, simulation results show that BSLSSVR-based thrust estimator can satisfy the requirement of direct thrust control, i.e. , maximum absolute value of relative error of thrust estimation is not more than 5‰.
文摘针对桥梁挠度监测中温度效应的分离问题,根据桥梁挠度的组分特性,利用最小二乘支持向量机(leastsquare support vector machines,LS-SVM)模型,提出桥梁挠度监测中精确分离温度效应的方法。温度和挠度温度效应具有确定的非线性关系。应用LS-SVM的逼近能力,将温度作为输入、挠度温度效应作为输出,建立温度和挠度温度效应的精确定量关系,在已知温度变化的情况下获取挠度温度效应的变化值,从而实现挠度温度效应准确分离。计算及分析结果表明,该方法能有效分离挠度监测信号中的温度效应,结合滤波方法,亦可有效分离出长期挠度,为结构的损伤识别提供了有效的数学手段和依据。
文摘在电池管理系统中为了使荷电状态量SOC(state of charge)估计精确,提出以遗传算法优化最小二乘支持向量机(LS-SVM)的方法对电池的SOC进行预测的模型。在电池变流情况下对SOC进行研究,以标准工况下的实验数据作为样本,以电池的电流、电压及温度作为训练模型的输入,SOC作为输出建立模型,使之能很好地适用于混合动力汽车用电池在变电流状态下的实时SOC估计。研究结果表明:该预测模型预测精度高,其最大相对误差小于3%,平均相对误差小于2%,且与神经网络预测结果相比具有更强的实用性。