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基于相关向量机的电站锅炉NO_x燃烧优化 被引量:8
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作者 牛培峰 马云鹏 +4 位作者 张京 张鑫 李国强 陈贵林 张先臣 《计量学报》 CSCD 北大核心 2016年第2期191-196,共6页
为了降低电站锅炉NOx排放量,采用一种新的机器学习方法——相关向量机对某330 MW煤粉汽包锅炉的一、二次风速以及含氧量等26个输入参数和NOx输出结果进行建模,并用万有引力算法对模型的参数进行优化,获得最优模型。与粒子群算法、遗传... 为了降低电站锅炉NOx排放量,采用一种新的机器学习方法——相关向量机对某330 MW煤粉汽包锅炉的一、二次风速以及含氧量等26个输入参数和NOx输出结果进行建模,并用万有引力算法对模型的参数进行优化,获得最优模型。与粒子群算法、遗传算法优化相关向量机以及万有引力算法优化支持向量机等进行了比较,选择锅炉输入参数中的可调变量为优化变量,以NOx低排放量为目标进行优化,获得低NOx排放的输入参数。结果证明:万有引力优化相关向量机算法建立的模型精确度比其它几种算法高,对模型进行低NOx优化后,NOx输出值由最初的的906.65 mg/m3变为550.600 mg/m3,下降幅度约为38.9%,实现了NOx排放量大幅度降低。 展开更多
关键词 NOx预测 相关向 万有引力算法 电站锅炉 优化
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Short-term prediction of photovoltaic power generation based on LMD-EE-ESN with error correction
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作者 YU Xiangqian LI Zheng 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期360-368,共9页
Considering the instability of the output power of photovoltaic(PV)generation system,to improve the power regulation ability of PV power during grid-connected operation,based on the quantitative analysis of meteorolog... Considering the instability of the output power of photovoltaic(PV)generation system,to improve the power regulation ability of PV power during grid-connected operation,based on the quantitative analysis of meteorological conditions,a short-term prediction method of PV power based on LMD-EE-ESN with iterative error correction was proposed.Firstly,through the fuzzy clustering processing of meteorological conditions,taking the power curves of PV power generation in sunny,rainy or snowy,cloudy,and changeable weather as the reference,the local mean decomposition(LMD)was carried out respectively,and their energy entropy(EE)was taken as the meteorological characteristics.Then,the historical generation power series was decomposed by LMD algorithm,and the hierarchical prediction of the power curve was realized by echo state network(ESN)prediction algorithm combined with meteorological characteristics.Finally,the iterative error theory was applied to the correction of power prediction results.The analysis of the historical data in the PV power generation system shows that this method avoids the influence of meteorological conditions in the short-term prediction of PV output power,and improves the accuracy of power prediction on the condition of hierarchical prediction and iterative error correction. 展开更多
关键词 photovoltaic(PV)power generation system short-term forecast local mean decomposition(LMD) energy entropy(EE) echo state network(ESN)
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Grain Yield Prediction for Irrigation District Based on LS-SVM 被引量:5
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作者 宰松梅 贾艳辉 +1 位作者 温季 郭冬冬 《Agricultural Science & Technology》 CAS 2009年第6期1-3,6,共4页
Commonly used grain yield forecasting models were briefly reviewed, and a yield prediction model of irrigation district was established based on least squares support vector machines (LS-SVM). The grain yield in irr... Commonly used grain yield forecasting models were briefly reviewed, and a yield prediction model of irrigation district was established based on least squares support vector machines (LS-SVM). The grain yield in irrigation district was analog calculated. And the test samples were used to compare with gray prediction, and neural network model. The maximum predicted error of least squares SVM was 7.12%, with an average error of 4.81%. The results showed that LS-SVM model has high prediction accuracy and strong generalization ability. So it could be used as a new method for irrigation district yield prediction 展开更多
关键词 YIELD PREDICTION LS-SVM MODEL
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Support vector machines approach to mean particle size of rock fragmentation due to bench blasting prediction 被引量:21
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作者 史秀志 周健 +2 位作者 吴帮标 黄丹 魏威 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期432-441,共10页
Aiming at the problems of the traditional method of assessing distribution of particle size in bench blasting, a support vector machines (SVMs) regression methodology was used to predict the mean particle size (X50... Aiming at the problems of the traditional method of assessing distribution of particle size in bench blasting, a support vector machines (SVMs) regression methodology was used to predict the mean particle size (X50) resulting from rock blast fragmentation in various mines based on the statistical learning theory. The data base consisted of blast design parameters, explosive parameters, modulus of elasticity and in-situ block size. The seven input independent variables used for the SVMs model for the prediction of X50 of rock blast fragmentation were the ratio of bench height to drilled burden (H/B), ratio of spacing to burden (S/B), ratio of burden to hole diameter (B/D), ratio of stemming to burden (T/B), powder factor (Pf), modulus of elasticity (E) and in-situ block size (XB). After using the 90 sets of the measured data in various mines and rock formations in the world for training and testing, the model was applied to 12 another blast data for validation of the trained support vector regression (SVR) model. The prediction results of SVR were compared with those of artificial neural network (ANN), multivariate regression analysis (MVRA) models, conventional Kuznetsov method and the measured X50 values. The proposed method shows promising results and the prediction accuracy of SVMs model is acceptable. 展开更多
关键词 rock fragmentation BLASTING mean panicle size (X50) support vector machines (SVMs) PREDICTION
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三粒子任意自旋态的隐形传输
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作者 王保如 闫凤利 《河北师范大学学报(自然科学版)》 CAS 2004年第4期361-364,共4页
研究了三粒子任意自旋态的隐形传输方案.考虑了测量设备的作用,以"纯粹的量子语言"———"预测量"的概念来描述量子隐形传态,从而避免了使用"测量坍缩"假设.
关键词 隐形传输 纠缠态 三粒子自旋态 探针 “预测量” 子力学
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Quantitative prediction of channel sand bodies based on seismic peak attributes in the frequency domain and its application 被引量:2
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作者 孙鲁平 郑晓东 +2 位作者 首皓 李劲松 李艳东 《Applied Geophysics》 SCIE CSCD 2010年第1期10-17,98,共9页
The boundary identification and quantitative thickness prediction of channel sand bodies are always difficult in seismic exploration.We present a new method for boundary identification and quantitative thickness predi... The boundary identification and quantitative thickness prediction of channel sand bodies are always difficult in seismic exploration.We present a new method for boundary identification and quantitative thickness prediction of channel sand bodies based on seismic peak attributes in the frequency domain.Using seismic forward modeling of a typical thin channel sand body,a new seismic attribute-the ratio of peak frequency to amplitude was constructed.Theoretical study demonstrated that seismic peak frequency is sensitive to the thickness of the channel sand bodies,while the amplitude attribute is sensitive to the strata lithology.The ratio of the two attributes can highlight the boundaries of the channel sand body.Moreover,the thickness of the thin channel sand bodies can be determined using the relationship between seismic peak frequency and thin layer thickness.Practical applications have demonstrated that the seismic peak frequency attribute can depict the horizontal distribution characteristics of channels very well.The ratio of peak frequency to amplitude attribute can improve the identification ability of channel sand body boundaries.Quantitative prediction and boundary identification of channel sand bodies with seismic peak attributes in the frequency domain are feasible. 展开更多
关键词 channel sand bodies seismic peak frequency attribute seismic peak amplitude attribute boundary identification quantitative prediction
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Predicting pillar stability for underground mine using Fisher discriminant analysis and SVM methods 被引量:16
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作者 周健 李夕兵 +2 位作者 史秀志 魏威 吴帮标 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2734-2743,共10页
The purpose of this study is to apply some statistical and soft computing methods such as Fisher discriminant analysis (FDA) and support vector machines (SVMs) methodology to the determination of pillar stability ... The purpose of this study is to apply some statistical and soft computing methods such as Fisher discriminant analysis (FDA) and support vector machines (SVMs) methodology to the determination of pillar stability for underground mines selected from various coal and stone mines by using some index and mechanical properties, including the width, the height, the ratio of the pillar width to its height, the uniaxial compressive strength of the rock and pillar stress. The study includes four main stages: sampling, testing, modeling and assessment of the model performances. During the modeling stage, two pillar stability prediction models were investigated with FDA and SVMs methodology based on the statistical learning theory. After using 40 sets of measured data in various mines in the world for training and testing, the model was applied to other 6 data for validating the trained proposed models. The prediction results of SVMs were compared with those of FDA as well as the measured field values. The general performance of models developed in this study is close; however, the SVMs exhibit the best performance considering the performance index with the correct classification rate Prs by re-substitution method and Pcv by cross validation method. The results show that the SVMs approach has the potential to be a reliable and practical tool for determination of pillar stability for underground mines. 展开更多
关键词 underground mine pillar stability Fisher discriminant analysis (FDA) support vector machines (SVMs) PREDICTION
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STUDY ON ARTIFICIAL NEURAL NETWORK FORECASTING METHOD OF WATER CONSUMPTION PER HOUR 被引量:5
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作者 刘洪波 张宏伟 +1 位作者 田林 王新芳 《Transactions of Tianjin University》 EI CAS 2001年第4期233-237,共5页
An artificial neural network (ANN) short term forecasting model of consumption per hour was built based on seasonality,trend and randomness of a city period of time water consumption series.Different hidden layer no... An artificial neural network (ANN) short term forecasting model of consumption per hour was built based on seasonality,trend and randomness of a city period of time water consumption series.Different hidden layer nodes,same inputs and forecasting data were selected to train and forecast and then the relative errors were compared so as to confirm the NN structure.A model was set up and used to forecast concretely by Matlab.It is tested by examples and compared with the result of time series trigonometric function analytical method.The result indicates that the prediction errors of NN are small and the velocity of forecasting is fast.It can completely meet the actual needs of the control and run of the water supply system. 展开更多
关键词 artificial neural network consumption per hour FORECAST BP algorithm MATLAB
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SVM method for predicting the thickness of sandstone 被引量:4
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作者 乐友喜 王俊 《Applied Geophysics》 SCIE CSCD 2007年第4期276-281,共6页
The Support Vector Machine (SVM) method can be used to set up a nonlinear function prediction model. It is based on the small sample learning theory. The kernel function can be constructed automatically based on the... The Support Vector Machine (SVM) method can be used to set up a nonlinear function prediction model. It is based on the small sample learning theory. The kernel function can be constructed automatically based on the actual sample data by using the SVM method. As a result, the function not only gets a higher fit precision but is also better generalized. The frequency spectrum and seismic waveform are related by Fourier transform, so they are two different forms of the same physical phenomenon. The variety of waveform character reflects stratigraphic differences and frequency spectrum differences reflect the variation of lithology, fluid composition, and formation thickness. It directly predicts sandstone thickness using the seismic waveform. This not only fully utilizes the seismic information but also greatly increases the accuracy of the prediction. Model examples and actual applications show the applicability of this method. 展开更多
关键词 Reservoir prediction seismic waveform Support Vector Machine GENERALIZATION
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Application of support vector machine in trip chaining pattern recognition and analysis of explanatory variable effects 被引量:2
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作者 杨硕 邓卫 程龙 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期106-114,共9页
In order to improve the accuracy of travel demand forecast and considering the distribution of travel behaviors within time dimension, a trip chaining pattern recognition model was established based on activity purpos... In order to improve the accuracy of travel demand forecast and considering the distribution of travel behaviors within time dimension, a trip chaining pattern recognition model was established based on activity purposes by applying three methods: the support vector machine (SVM) model, the radial basis function neural network (RBFNN) model and the multinomial logit (MNL) model. The effect of explanatory factors on trip chaining behaviors and their contribution to model performace were investigated by sensitivity analysis. Results show that the SVM model has a better performance than the RBFNN model and the MNL model due to its higher overall and partial accuracy, indicating its recognition advantage under a smai sample size scenario. It is also proved that the SVM model is capable of estimating the effect of multi-category factors on trip chaining behaviors more accurately. The different contribution of explanatory, factors to trip chaining pattern recognition reflects the importance of refining trip chaining patterns ad exploring factors that are specific to each pattern. It is shown that the SVM technology in travel demand forecast modeling and analysis of explanatory variable effects is practical. 展开更多
关键词 trip chaining patterns support vector machine recognition performance sensitivity analysis
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Rock critical porosity inversion and S-wave velocity prediction 被引量:3
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作者 张佳佳 李宏兵 姚逢昌 《Applied Geophysics》 SCIE CSCD 2012年第1期57-64,116,共9页
A critical porosity model is often used to calculate the dry frame elastic modulus by the rock critical porosity value which is affected by many factors. In practice it is hard for us to obtain an accurate critical po... A critical porosity model is often used to calculate the dry frame elastic modulus by the rock critical porosity value which is affected by many factors. In practice it is hard for us to obtain an accurate critical porosity value and we can generally take only an empirical critical porosity value which often causes errors. In this paper, we propose a method to obtain the rock critical porosity value by inverting P-wave velocity and applying it to predict S-wave velocity. The applications of experiment and log data both show that the critical porosity inversion method can reduce the uncertainty resulting from using an empirical value in the past and provide the accurate critical porosity value for predicting S-wave velocity which significantly improves the prediction accuracy. 展开更多
关键词 Gassmann's equations dry frame critical porosity critical porosity model S-wave velocity prediction
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Expressway traffic flow prediction using chaos cloud particle swarm algorithm and PPPR model 被引量:2
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作者 赵泽辉 康海贵 李明伟 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期328-335,共8页
Aiming at the real-time fluctuation and nonlinear characteristics of the expressway short-term traffic flow forecasting the parameter projection pursuit regression PPPR model is applied to forecast the expressway traf... Aiming at the real-time fluctuation and nonlinear characteristics of the expressway short-term traffic flow forecasting the parameter projection pursuit regression PPPR model is applied to forecast the expressway traffic flow where the orthogonal Hermite polynomial is used to fit the ridge functions and the least square method is employed to determine the polynomial weight coefficient c.In order to efficiently optimize the projection direction a and the number M of ridge functions of the PPPR model the chaos cloud particle swarm optimization CCPSO algorithm is applied to optimize the parameters. The CCPSO-PPPR hybrid optimization model for expressway short-term traffic flow forecasting is established in which the CCPSO algorithm is used to optimize the optimal projection direction a in the inner layer while the number M of ridge functions is optimized in the outer layer.Traffic volume weather factors and travel date of the previous several time intervals of the road section are taken as the input influencing factors. Example forecasting and model comparison results indicate that the proposed model can obtain a better forecasting effect and its absolute error is controlled within [-6,6] which can meet the application requirements of expressway traffic flow forecasting. 展开更多
关键词 expressway traffic flow forecasting projectionpursuit regression particle swarm algorithm chaoticmapping cloud model
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STUDY ON OPTIMAL CONTROL OF MUNICIPAL WATER DISTRIBUTION NETWORK 被引量:1
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作者 张宏伟 杨芳 庄健 《Transactions of Tianjin University》 EI CAS 2001年第3期167-171,共5页
A systematic investigation is made on the problems which are related to the optimal control of the municipal water distribution network.A mathematical model of forecasting the water short term demand is proposed using... A systematic investigation is made on the problems which are related to the optimal control of the municipal water distribution network.A mathematical model of forecasting the water short term demand is proposed using the time series trigonometric function analysis method;the service discharge based macroscopic model of network performance is established using the network structuring method;a relatively satisfactory mathematical model for the optimal control of water distribution network is put forward in view of security and economy,and solved by the constrained mixed discrete variable complex arithmetic.The model is applied in many examples and the results are satisfactory. 展开更多
关键词 water distribution network water demand forecast macroscopic model optimal control
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Research on Damage Law of Asterococcus muratae Kuwana
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作者 李枷霖 秦帆 +2 位作者 谢亚可心 毛安元 蔡平 《Agricultural Science & Technology》 CAS 2014年第1期102-104,共3页
[Objective] The aim is to investigate the impact of different host plants, planting methods and directions on the damage law of Asterococcus muratae. [Method] The quantity of pests, size of female pests and quantity o... [Objective] The aim is to investigate the impact of different host plants, planting methods and directions on the damage law of Asterococcus muratae. [Method] The quantity of pests, size of female pests and quantity of ova of A. mu-ratae in Suzhou in different host plants under two planting methods and in four di-rections of a host plant were measured. [Result] A. muratae exhibits selectivity to host plants, and their quantity, female pest size and reproductive capacity are higher in Magnolia grandiflora(southern magnolia) than in other plants. The four directions of the host plant suffer to different extents, and the north part is usual y the most in-jured. Mass-planted southern magnolias are more seriously impacted than individual y-planted ones. Both size and weight of a female pest have significant linear relations with ovum quantity, and the weight of a female pest is more closely related to its ovum quantity. Based on the weight of a female pest, we can predict the exact ovum quantity according to the equation y=2E-05x+0.003 7. [Conclusion] The research re-sults provide reference for making an effective control plan for A. muratae. 展开更多
关键词 Asterococcus muratae Kuwana Damage law Ovum quantity prediction
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Assessing dynamic modulus properties for typical asphalt mixtures in Jiangsu
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作者 王昊鹏 杨军 +1 位作者 周文章 陈先华 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期99-105,共7页
To investigate the validity of two dynamic modulus predictive models( Witczak 1-37 A viscosity-based model and Witczak 1-40 D shear modulus-based model) in the context of Jiangsu, and evaluate the effect of differen... To investigate the validity of two dynamic modulus predictive models( Witczak 1-37 A viscosity-based model and Witczak 1-40 D shear modulus-based model) in the context of Jiangsu, and evaluate the effect of different mixture design variables( aggregate gradations, binder type, and volumetric properties) on dynamic modulus E*, asphalt mixtures commonly used in the local surface layer, including Sup-13 and AC-13, are prepared in the laboratory and their dynamic modulus E*values are predicted based on the above mentioned models. The corresponding asphalt tests, including viscosity and dynamic shear modulus tests, are also carried out to obtain the prediction model parameters. The test results showthat binder type and asphalt content have a significant impact on dynamic modulus.There is a good correlation between the E*values based on above two predictive models and the measured E*, while a relatively lower bias can be expected from Witczak 1-37 A model. The test results can be used for the calibration of dynamic modulus with higher accuracy. 展开更多
关键词 dynamic modulus prediction models asphalt pavement Witczak 1-37A Witczak 1-40D mechanistic empirical pavement design guide
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Study on the Yield Prediction Model of Processing Tomato Based on the Grey System Theory 被引量:1
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作者 袁莉 姜波 《Agricultural Science & Technology》 CAS 2011年第5期632-633,642,共3页
[Objective] The research aimed to study the yield prediction model of processing tomato based on the grey system theory.[Method] The variation trend of processing tomato yield was studied by using the grey system theo... [Objective] The research aimed to study the yield prediction model of processing tomato based on the grey system theory.[Method] The variation trend of processing tomato yield was studied by using the grey system theory,and GM(1,1)grey model of processing tomato yield prediction was established.The processing tomato yield in Xinjiang during 2001-2009 was as the example to carry out the instance analysis.[Result] The model had the high forecast accuracy and strong generalization ability,and was reliable for the prediction of recent processing tomato yield.[Conclusion] The research provided the reference for the macro-control of tomato industry,the processing and storage of tomato in Xinjiang. 展开更多
关键词 Grey system theory Grey prediction model Processing tomato yield
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Efficient fundamental frequency transformation for voice conversion
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作者 宋鹏 金赟 +2 位作者 包永强 赵力 邹采荣 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期140-144,共5页
In order to improve the performance of voice conversion, the fundamental frequency (F0) transformation methods are investigated, and an efficient F0 transformation algorithm is proposed. First, unlike the traditiona... In order to improve the performance of voice conversion, the fundamental frequency (F0) transformation methods are investigated, and an efficient F0 transformation algorithm is proposed. First, unlike the traditional linear transformation methods, the relationships between F0s and spectral parameters are explored. In each component of the Gaussian mixture model (GMM), the F0s are predicted from the converted spectral parameters using the support vector regression (SVR) method. Then, in order to reduce the over- smoothing caused by the statistical average of the GMM, a mixed transformation method combining SVR with the traditional mean-variance linear (MVL) conversion is presented. Meanwhile, the adaptive median filter, prevalent in image processing, is adopted to solve the discontinuity problem caused by the frame-wise transformation. Objective and subjective experiments are carried out to evaluate the performance of the proposed method. The results demonstrate that the proposed method outperforms the traditional F0 transformation methods in terms of the similarity and the quality. 展开更多
关键词 F0 prediction support vector regression meanvariance linear conversion adaptive median filter
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Tribological properties and wear prediction model of TiC particles reinforced Ni-base alloy composite coatings 被引量:4
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作者 谭业发 何龙 +2 位作者 王小龙 洪翔 王伟刚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第8期2566-2573,共8页
TiC particles reinforced Ni-based alloy composite coatings were prepared on 7005 aluminum alloy by plasma spray. The effects of load, speed and temperature on the tribological behavior and mechanisms of the composite ... TiC particles reinforced Ni-based alloy composite coatings were prepared on 7005 aluminum alloy by plasma spray. The effects of load, speed and temperature on the tribological behavior and mechanisms of the composite coatings under dry friction were researched. The wear prediction model of the composite coatings was established based on the least square support vector machine (LS-SVM). The results show that the composite coatings exhibit smaller friction coefficients and wear losses than the Ni-based alloy coatings under different friction conditions. The predicting time of the LS-SVM model is only 12.93%of that of the BP-ANN model, and the predicting accuracies on friction coefficients and wear losses of the former are increased by 58.74%and 41.87%compared with the latter. The LS-SVM model can effectively predict the tribological behavior of the TiCP/Ni-base alloy composite coatings under dry friction. 展开更多
关键词 TiC particles Ni-based alloy composite coating least square support vector machine(LS-SVM) wear prediction model
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Multivariable Fuzzy Predictive Control Based on the Modified CPN Model
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作者 郑怀林 陈维南 《Journal of Southeast University(English Edition)》 EI CAS 1998年第1期108-113,共6页
Through modifying the CPN model, a kind of multivariable fuzzy model is put forward, and the matching fuzzy multistep predictive control algorithm is deduced based on the model. The modified model works in a competiti... Through modifying the CPN model, a kind of multivariable fuzzy model is put forward, and the matching fuzzy multistep predictive control algorithm is deduced based on the model. The modified model works in a competitive output manner which results in its local representation property. While studying on line, only a few parameters need to be regulated. So the model has the merits of fast learning and on line self organizing modeling. The control algorithm is simple, adaptive and useful in multivariable and time delay systems. Applying the algorithm in a paper making system, simulation shows its good effect. 展开更多
关键词 modified CPN model fuzzy predictive control MULTIVARIABLE time delay systems
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Application of Climatic Productivity in the Analysis of Vegetable Yield
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作者 李强 李家启 +2 位作者 吉莉 汪志辉 冉静 《Agricultural Science & Technology》 CAS 2012年第12期2603-2606,共4页
[Objective] Climatic productivity was applied to forecast and analyse the vegetable yield. [Method] Climatic productivity model presented by Zhou and the long-range climate forecasting method were adopted to analyse c... [Objective] Climatic productivity was applied to forecast and analyse the vegetable yield. [Method] Climatic productivity model presented by Zhou and the long-range climate forecasting method were adopted to analyse characteristics of the change of climatic productivity potential at Beibei District in combination with the ac- tual vegetable yield. [Result] The change of climatic productivity at Beibei District was fluctuant in an stable overall trend. The difference of spatial distribution of cli- matic productivity was apparent, with high climatic productivity potential in the north- east; in the actual production, vegetable yield was declining and it was the same with the climate use efficiency; according to the prediction, the vegetable yield would increase slightly in the future 10 years. [Conclusion] This study provides bases for the reasonable plan and layout of vegetable plantation under the climatic condition at Beibei District, as well as the selection of vegetable cultivars. 展开更多
关键词 Climatic productivity Vegetable yield PREDICTION
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