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相依线性回归系统的压缩估计
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作者 李胜宏 周占功 《江苏科技大学学报(自然科学版)》 CAS 北大核心 2010年第2期197-200,共4页
对于相依线性回归系统(SUR,m=2),其设计阵为病态时,文中给出了βi(i=1,2)的压缩估计及相应的两步估计,证明了在θi(i=1,2,…,p1)满足一定条件时,此估计相对于协方差改进估计及两步协方差改进估计的优良性,同时给出了θi(i=1,2,…,p1)的... 对于相依线性回归系统(SUR,m=2),其设计阵为病态时,文中给出了βi(i=1,2)的压缩估计及相应的两步估计,证明了在θi(i=1,2,…,p1)满足一定条件时,此估计相对于协方差改进估计及两步协方差改进估计的优良性,同时给出了θi(i=1,2,…,p1)的确定方法. 展开更多
关键词 相依线性回归系统 压缩估计 协方差改进估计 两步估计
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较弱条件下线性回归系统回归系数协方差改进估计的弱相合性
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作者 杨智应 《广西民族大学学报(自然科学版)》 CAS 1994年第2期25-33,共9页
对于由m个相依的线性回归方程组成的线性回归系统:其中Yi为n×1观测向量,Xi为n×Pi列满秩矩阵,βi为Pi×1的未知回归系数,ei为n×1随机误差向量,且σij≠0.[1]的作者分别在已知及未知的... 对于由m个相依的线性回归方程组成的线性回归系统:其中Yi为n×1观测向量,Xi为n×Pi列满秩矩阵,βi为Pi×1的未知回归系数,ei为n×1随机误差向量,且σij≠0.[1]的作者分别在已知及未知的情况下给出了β1的协方差改进估计和两步改进估计β1,并在ε=(e1,…,em)的各行相互独立同分布的情况下讨论了β1的弱相合性.本文在较弱条件下讨论β1及B1的弱相合性,从而推广了[1]中相应的结果. 展开更多
关键词 线性回归系统 协方差改进估计 两步改进估计 弱相合 依概率收敛.
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相依线性回归系统回归系数协方差改进估计的收敛性及其计算机求解
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作者 杨智应 《现代计算机》 1998年第5期20-22,共3页
本文城较弱条件下给出βi的协方差改进估计βi及两步改进估计的收敛性质,
关键词 线性回归系统 回归系数 协方差估计 计算机
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降秩相依回归系统的泛岭改进估计
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作者 陈世基 廖东芳 《福建师范大学学报(自然科学版)》 CAS CSCD 1998年第3期1-8,共8页
对于二个相依回归系统yi=Xiβi+ei,E(ei)=0,Cov(ei,ej)=σijI(i,j=1,2),当设计阵Xi(i=1,2)为n×pi的列满秩阵时,其参数的估计已为许多学者所研究.在Xi(i=1,2)不... 对于二个相依回归系统yi=Xiβi+ei,E(ei)=0,Cov(ei,ej)=σijI(i,j=1,2),当设计阵Xi(i=1,2)为n×pi的列满秩阵时,其参数的估计已为许多学者所研究.在Xi(i=1,2)不是列满秩阵的情况,提出一种新的估计——降秩泛岭改进估计,并且探讨了这种估计及其相应的两步估计的各种性质. 展开更多
关键词 线性回归系统 估计 协方差 广义逆
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Performance of the geometric approach to fault detection and isolation in SISO,MISO,SIMO and MIMO systems 被引量:2
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作者 RAHIMI N. SADEGHI M. H. MAHJOOB M. J. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第9期1443-1451,共9页
In this paper, a geometric approach to fault detection and isolation (FDI) is applied to a Multiple-Input Multipie-Output (MIMO) model of a frame and the FDI results are compared to the ones obtained in the Single... In this paper, a geometric approach to fault detection and isolation (FDI) is applied to a Multiple-Input Multipie-Output (MIMO) model of a frame and the FDI results are compared to the ones obtained in the Single-Input Single-Output (SISO), Multiple-Input Single-Output (MISO), and Single-Input Multiple-Output (SIMO) cases. A proper distance function based on parameters obtained from parametric system identification method is used in the geometric approach. ARX (Auto Regressive with exogenous input) and VARX (Vector ARX) models with 12 parameters are used in all of the above-mentioned models. The obtained results reveal that by increasing the number of inputs, the classification errors reduce, even in the case of applying only one of the inputs in the computations. Furthermore, increasing the number of measured outputs in the FDI scheme results in decreasing classification errors. Also, it is shown that by using probabilistic space in the distance function, fault diagnosis scheme has better performance in comparison with the deterministic one. 展开更多
关键词 Fault detection and isolation (FDI) Multivariate systems Parametric system identification Linear regression Distance functions
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The Pre-test Principal Components Estimator in the Two Seemingly Unrelated Regression System
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作者 归庆明 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第4期57-61, ,共5页
For the two seemingly unrelated regression system, this paper proposed a new type of estimator called pre-test principal components estimator (PTPCE) and discussed some properties of PTPCE.
关键词 semmingly unrelated regression system pre-test principal components estimator
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Shoreline Change Prediction Model for Coastal Zone Management in Thailand 被引量:1
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作者 Siriluk Prukpitikul Varatip Buakaew Watchara Keshdet Apisit Kongprom Nuttom Kaewpoo 《Journal of Shipping and Ocean Engineering》 2012年第4期238-243,共6页
The prediction of shoreline erosion is vital for coastal management. This study aims to utilize geo-informatics technology to increase accuracy of a shoreline prediction model along two study sites in Samutprakarn pro... The prediction of shoreline erosion is vital for coastal management. This study aims to utilize geo-informatics technology to increase accuracy of a shoreline prediction model along two study sites in Samutprakarn province and in Prachuabkirikhan province. Predicting coastline change using remote sensing together with GIS (geographic information system) is a spat^o-temporal technology, which can continuously provide perspectives of coastal areas. Due to a long term of operational period of LANDSAT satellite, it is useful to enhance accuracy of prediction model. LANDSAT-5 TM images acquired during 1999-2009 were used to produce historical shoreline vectors. Physical data were modified to be input data of digital shoreline analysis system. The model was validated. Linear regressions were applied in order to derive equations of erosion magnitude. The result presents that averaged erosion and accretion rate along Samutprakarn province was 22.30 meters/year and 2.94 meters/year, respectively. On the other hand, the average rate of coastal erosion along Prachuabkirikhan province was much lower, being 2.48 meters/year while the accretion rate was approximately 4.11 meters/year. The predicted shoreline change at Samutprakarn province in 2019 is about -132.69 ~ 0.758 meters while at Prachuabkirikhan is 40.58 ~ 0.0012 meters. In conclusion, this prediction model focused the changing of shoreline in long term and accuracy of the model could be improved by increasing number of shorelines vectors, transect intervals and resolution of satellite images. Clearly, the model is flexible and can be applied in other particular areas for coastal zone management in Thailand. 展开更多
关键词 Shoreline change coastal prediction model geo-informatics technology.
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Application of Grey System GM (1,1) model and unary linear regression model in coal consumption of Jilin Province 被引量:1
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作者 TIAN Songlin LU Laijun 《Global Geology》 2015年第1期26-31,共6页
The data on the coal production and consumption in Jilin Province for the last ten years were collected,and the Grey System GM( 1,1) model and unary linear regression model were applied to predict the coal consumption... The data on the coal production and consumption in Jilin Province for the last ten years were collected,and the Grey System GM( 1,1) model and unary linear regression model were applied to predict the coal consumption of Jilin Production in 2014 and 2015. Through calculation,the predictive value on the coal consumption of Jilin Province was attained,namely consumption of 2014 is 114. 84 × 106 t and of 2015 is 117. 98 ×106t,respectively. Analysis of error data indicated that the predicted accuracy of Grey System GM( 1,1) model on the coal consumption in Jilin Province improved 0. 21% in comparison to unary linear regression model. 展开更多
关键词 Grey System GM 1 1 model unary linear regression model model test PREDICTION coal con-sumption Jilin Province
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Competitive Adsorption of Phenol and Lead from Synthetic Wastewater onto Granular Activated Carbon
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作者 A.H. Sulaymon D.W. Abbood A.H. Ali 《Journal of Environmental Science and Engineering》 2011年第11期1389-1399,共11页
The equilibrium uptake of phenol and lead(II) ions, both singly and in combination, by granular activated carbon was studied in a batch system. The initial pH, temperature, mixing speed and contact time were fixed a... The equilibrium uptake of phenol and lead(II) ions, both singly and in combination, by granular activated carbon was studied in a batch system. The initial pH, temperature, mixing speed and contact time were fixed at 4, 30 ℃, 250 rpm and 6 hrs respectively. Adsorption isotherms were developed for both the single and binary component systems and expressed by ten models for single and four models for binary systems and model parameters were estimated by the non-linear regression method using STATISTICA version-6 and EXCEEL-2007 software. The maximum loading capacity (qm) of the phenol was 66.8234, 60.4823 mg/g and 37.0370, 13.0988 mg/g for lead in single and binary systems respectively. Desorption experiments indicate that the desorption efficiency with 0.1 M NaOH, 0.1 M HCI solution reaches 97.35%, 98% for phenol and lead respectively. There was only 3.58%, 4.93% decrease in removal efficiency for phenol and lead respectively when used regenerated GAC for one cycle. 展开更多
关键词 ADSORPTION GAC PHENOL LEAD adsorption isotherms
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Do Satisfaction and Loyalty Have a Linear Relationship? Effect of the Education Level on Arts Participation
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作者 Javier Flores-Zamora Jesus Garcia-Madariaga 《Journal of Modern Accounting and Auditing》 2012年第4期529-536,共8页
This paper aims to explore the relationship between perceived satisfaction and loyalty of Spanish arts participants. Evidence suggests that customer satisfaction plays a key role in an organization's ability to maint... This paper aims to explore the relationship between perceived satisfaction and loyalty of Spanish arts participants. Evidence suggests that customer satisfaction plays a key role in an organization's ability to maintain a relationship with its customers. We examined the link between satisfaction and loyalty within a theoretical framework based on an empirical study in which data from more than 14,000 respondents were obtained. This data allowed us to evaluate the arts consumer from an attitudinal and behavioral perspective looking at their interests, satisfaction level, frequency of attendance, and compare it using the participant's education level. A descriptive statistical analysis using ANOVA (analysis of variance), correlation, partial correlation, and multiple regression provided evidence that, in the context of experiencing an arts show, satisfaction does not have any impact on loyalty but education level plays a significant role in people's interest and loyalty. 展开更多
关键词 SATISFACTION LOYALTY arts marketing LEISURE AUDIENCE ANOVA (analysis of variance)
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Evolution and Effects of the Social-ecological System in Karst Mountainous Regions:A Case Study of Guangxi,China 被引量:1
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作者 GONG Ni ZHAO Yuluan 《Journal of Resources and Ecology》 CSCD 2024年第4期991-1003,共13页
Karst regions are the typical areas of interaction between human society and natural ecosystems.Understanding the historical mechanisms of the evolution of social-ecological systems(SES)is crucial for the future susta... Karst regions are the typical areas of interaction between human society and natural ecosystems.Understanding the historical mechanisms of the evolution of social-ecological systems(SES)is crucial for the future sustainable management of karst regions.This study selected Guangxi,a typical karst mountainous region in Southwest China,as the study area,and used population,cropland area,and forest coverage as the SES elements.Based on the framework of SES research in the karst region,it adopted segmented linear regression to identify the stages of the interactions among these elements,to reveal the evolutionary stages of social development from the long-term perspective.In addition,the driving factor indicators were constructed from the aspects of natural environment,social development,government policy,and climate change,and then the feedback changes brought about by the evolution were investigated.The results show that the evolution of SES in Guangxi from 1363-2020 can be divided into seven stages.In the first,second,and early period of the third stages,the government of Guangxi mainly focused on agricultural activities,although the only way to meet the growing demand for food was by expanding the area of cropland,and the timber trade’s pursuit of economic development,resulting in an increase in rocky desertification.In the fourth stage,the ecological environment improved under the implementation of measures such as the control of rocky desertification and the compensation of forest ecological benefits.After the fifth stage,the effect of rocky desertification control has been remarkable.Although the implementation of relevant policies has alleviated the environmental problems to some extent,the continual changes in the structure and function of SES can challenge further progress towards sustainability in karst regions.This study aims to provide a reference for the long-term national spatial planning and the development of environmental policies in karst regions. 展开更多
关键词 EVOLUTION EFFECT Karst region piecewise linear regression social-ecological systems
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Nitrous Oxide Emissions from a Masson Pine Forest Soil in Subtropical Central China 被引量:3
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作者 CHEN Dan FU Xiao-Qing +6 位作者 WANG Cong LIU Xin-Liang LI Hang SHEN Jian-Lin WANG Yi LI Yong WU Jin-Shui 《Pedosphere》 SCIE CAS CSCD 2015年第2期263-274,共12页
The forest ecosystem plays a pivotal role in contributing greenhouse gases to the atmosphere.In order to characterize the temporal pattern of nitrous oxide(N_2O) emissions and identify the key factors affecting N_2O e... The forest ecosystem plays a pivotal role in contributing greenhouse gases to the atmosphere.In order to characterize the temporal pattern of nitrous oxide(N_2O) emissions and identify the key factors affecting N_2O emissions from a Masson pine forest in a hilly red-soil region in subtropical central China,we measured the N_2O emissions in Jinjing of Hunan Province using the static chambergas chromatographic method for 3 years(2010-2012) and analyzed the relationships between the N_2O fluxes and the environmental variables.Our results revealed that the N_2O fluxes over the 3 years varied from-36.0 to 296.7 μg N m^(-2) h^(-1),averaging 18.4±5.6 μg N m^(-2) h^(-1)(n=3).The average annual N_2O emissions were estimated to be 1.6±0.3 kg N ha^(-1) year^(-1).The N_2O fluxes exhibited clear intra-annual(seasonal) variations as they were higher in summers and lower in winters.Compared with other forest observations in the subtropics,N_2O emissions at our site were relatively high,possibly due to the high local dry/wet N deposition,and were mostly sensitive to variations in precipitation and soil ammonium N content.In this work,a multiple linear regression model was developed to determine the influence of environmental factors on N_2O emissions,in which a category predictor of "Season" was intentionally used to account for the seasonal variation of the N_2O fluxes.Such a model explained almost 40%of the total variation in daily N_2O emissions from the Masson pine forest soil studied(P<0.001). 展开更多
关键词 environmental factors multiple linear regression model N deposition SEASON subtropical forests
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Variability features of the width of the tropical belt from COSMIC radio occultation data
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作者 GAO Pan ZHANG XiaoHong XU XiaoHua 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第4期795-802,共8页
In this work, we analyzed time-series and trends of the tropical belt edges and widths with three methods based on the tropopause using new global positioning system radio occultation(GPS RO) data from the Constellati... In this work, we analyzed time-series and trends of the tropical belt edges and widths with three methods based on the tropopause using new global positioning system radio occultation(GPS RO) data from the Constellation Observing System for Meteorology, Ionosphere, and Climate(COSMIC) mission for September 2006–February 2014. The results from the three methods agreed well with previous studies and new features were found. To avoid the El Ni?o Southern Oscillation(ENSO) and Quasi-Biennial Oscillation(QBO) influence, we applied a simple multiple linear regression model to the monthly anomalies to obtain the tropical belt edges and width trends. During the study, we found equatorward movements of the tropical belt edges on both hemispheres. The narrowing of the tropical belt mainly occurred in the Pacific Ocean. We also found that the deseasonalized monthly anomalies of the tropical belt width were closely related with the ENSO and QBO. The tropical belt at a height of 15 km was mostly closely related with the ENSO. The correlations between the QBO and the tropical belt were consistent for the three methods. 展开更多
关键词 COSMIC GPS Radio Occultation Tropical belt width TROPOPAUSE
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Denitrification Rates and Their Controlling Factors in Streams of the Han River Basin with Different Land-Use Patterns 被引量:1
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作者 S.P.JUNG Y.J.KIM H.KANG 《Pedosphere》 SCIE CAS CSCD 2014年第4期516-528,共13页
Land-use patterns can affect various nutrient cycles in stream ecosystems, but little information is available about the effects of urban development on denitrification processes at the watershed scale. In the present... Land-use patterns can affect various nutrient cycles in stream ecosystems, but little information is available about the effects of urban development on denitrification processes at the watershed scale. In the presented study, we investigated the controlling factors of denitrification rates within the streams of the Han River Basin, Korea, with different land-use patterns, in order to enhance the effectiveness of water resource management strategies. Ten watersheds were classified into three land-use patterns (forest, agriculture and urban) using satellite images and geographic information system techniques, and in-situ denitrification rates were determined using an acetylene blocking method. Additionally, sediment samples were collected from each stream to analyze denitrifier communities and abundance using molecular approaches. In-situ denitrification rates were found to be in the order of agricultural streams (289.6 mg N20-N m-2 d-1) 〉 urban streams (157.0 mg N20-N m-2 d-1) 〉 forested streams (41.9 mg N20-N m-2 d-l). In contrast, the average quantity of denitrifying genes was the lowest in the urban streams. Genetic diversity of denitrifying genes was not affected by watershed land-use pattern, but exhibited stream-dependent pattern. More significance factors were involved in denitrification in the sites with higher denitrification rates. Multiple linear regression analysis revealed that clay, dissolved organic carbon and water contents were the main factors controlling denitrification rate in the agricultural streams, while dissolved organic carbon was the main controlling factor in the urban streams. In contrast, temperature appeared to be the main controlling factor in the forested streams. 展开更多
关键词 denitrifier communities denitrifying genes nutrient cycle stream ecosystem
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