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Application of neural network model coupling with the partial least-squares method for forecasting watre yield of mine 被引量:2
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作者 陈南祥 曹连海 黄强 《Journal of Coal Science & Engineering(China)》 2005年第1期40-43,共4页
Scientific forecasting water yield of mine is of great significance to the safety production of mine and the colligated using of water resources. The paper established the forecasting model for water yield of mine, co... Scientific forecasting water yield of mine is of great significance to the safety production of mine and the colligated using of water resources. The paper established the forecasting model for water yield of mine, combining neural network with the partial least square method. Dealt with independent variables by the partial least square method, it can not only solve the relationship between independent variables but also reduce the input dimensions in neural network model, and then use the neural network which can solve the non-linear problem better. The result of an example shows that the prediction has higher precision in forecasting and fitting. 展开更多
关键词 water yield of mine partial least square method neural network forecasting model
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Penalized total least squares method for dealing with systematic errors in partial EIV model and its precision estimation 被引量:3
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作者 Leyang Wang Luyun Xiong Tao Chen 《Geodesy and Geodynamics》 CSCD 2021年第4期249-257,共9页
When the total least squares(TLS)solution is used to solve the parameters in the errors-in-variables(EIV)model,the obtained parameter estimations will be unreliable in the observations containing systematic errors.To ... When the total least squares(TLS)solution is used to solve the parameters in the errors-in-variables(EIV)model,the obtained parameter estimations will be unreliable in the observations containing systematic errors.To solve this problem,we propose to add the nonparametric part(systematic errors)to the partial EIV model,and build the partial EIV model to weaken the influence of systematic errors.Then,having rewritten the model as a nonlinear model,we derive the formula of parameter estimations based on the penalized total least squares criterion.Furthermore,based on the second-order approximation method of precision estimation,we derive the second-order bias and covariance of parameter estimations and calculate the mean square error(MSE).Aiming at the selection of the smoothing factor,we propose to use the U curve method.The experiments show that the proposed method can mitigate the influence of systematic errors to a certain extent compared with the traditional method and get more reliable parameter estimations and its precision information,which validates the feasibility and effectiveness of the proposed method. 展开更多
关键词 partial EIV model Systematic errors Nonlinear model Penalized total least squares criterion U curve method
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Partial Least Squares Structural Equation Path Modelling Determined Predictors of Students Reported Human Cadaver Dissection Activity
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作者 Ian G. Munabi William Buwembo 《Forensic Medicine and Anatomy Research》 2020年第2期18-37,共20页
Human cadaver dissection remains a core and preferred method of anatomical instruction at most low- and middle-income health professional training institutions. Dissection, which is both traumatic and stressful, sets ... Human cadaver dissection remains a core and preferred method of anatomical instruction at most low- and middle-income health professional training institutions. Dissection, which is both traumatic and stressful, sets the tone of the students’ responses to later and or similar stressful learning opportunities like the post-mortems or care for terminally ill patients. Partial least squares structural equation modelling was used to determine the effect of the students’: personality, perception of the learning environment, learning approach, and effect of the environment on the student, on undergraduate health professional student’s activity in the human cadaver dissection room. This was a secondary analysis of previously collected data from a cross sectional survey of undergraduate health professional students. We found that personality type and perception of the environment had a positive effect on dissection room activity. Approach to learning and being affected by the dissection room experience (impact), had a negative effect on dissection room activity. All the above effects on dissection room activity were not significant. This study showed that personality, perception of the learning environment, learning approach and effect of the environment on the student, had effects on undergraduate health professional student’s activity in the human cadaver dissection room. The modelled effects are opportunities for educational interventions aimed at increasing student activity in the dissection room. 展开更多
关键词 ANATOMY DISSECTION CADAVER partial least squares Structural Equation modeling
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A multivariate partial least squares approach to joint association analysis for multiple correlated traits 被引量:3
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作者 Yang Xu Wenming Hu +1 位作者 Zefeng Yang Chenwu Xu 《The Crop Journal》 SCIE CAS CSCD 2016年第1期21-29,共9页
Many complex traits are highly correlated rather than independent. By taking the correlation structure of multiple traits into account, joint association analyses can achieve both higher statistical power and more acc... Many complex traits are highly correlated rather than independent. By taking the correlation structure of multiple traits into account, joint association analyses can achieve both higher statistical power and more accurate estimation. To develop a statistical approach to joint association analysis that includes allele detection and genetic effect estimation, we combined multivariate partial least squares regression with variable selection strategies and selected the optimal model using the Bayesian Information Criterion(BIC). We then performed extensive simulations under varying heritabilities and sample sizes to compare the performance achieved using our method with those obtained by single-trait multilocus methods. Joint association analysis has measurable advantages over single-trait methods, as it exhibits superior gene detection power, especially for pleiotropic genes. Sample size, heritability,polymorphic information content(PIC), and magnitude of gene effects influence the statistical power, accuracy and precision of effect estimation by the joint association analysis. 展开更多
关键词 Association analysis MULTIPLE CORRELATED TRAITS Supersaturated model MULTILOCUS MULTIVARIATE partial least squares
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Factors influencing the internet banking adoption decision in North Cyprus: an evidence from the partial least square approach of the structural equation modeling 被引量:2
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作者 Hiba Alhassany Faisal Faisal 《Financial Innovation》 2018年第1期422-442,共21页
Purpose:This paper aims to examine how the adoption decision of the internet banking in North Cyprus would be affected based on the following dimensions;the technology features,the personal characteristics,the social ... Purpose:This paper aims to examine how the adoption decision of the internet banking in North Cyprus would be affected based on the following dimensions;the technology features,the personal characteristics,the social environment and the expected risk.Design/methodology/approach:A self-administered survey was conducted with 291 participants responded to it.The partial least square approach of the structural equation modeling(PLS-SEM)is employed to investigate the direct effects of the proposed factors on the adoption decision.Additionally,the mediation test is used to examine indirect effects.Findings:Results showed that even though the participants appreciated the benefits of the online banking as the perceived usefulness factor exerts the greatest direct effect,they would rather use clear and easy-to-use websites,adding to that their assessments of the usefulness of these services are significantly influenced by the surrounding people’s views and prior experience.This is demonstrated by the total effects of the perceived ease of use and the subjective norm factors,which are greater than the direct effect of the perceived usefulness factor since both of these factors have significant direct and indirect effects mediated by the perceived usefulness factor.The negative impact of the perceived risk factor is weak compared to the previous factors.While the personal innovativeness factor showed the weakest effect among the proposed factors. 展开更多
关键词 Behavioral theories Technology adoption TAM Subjective norm Personal innovativeness Perceived risk partial least square Structural equation modeling
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Chaotic time series multi-step direct prediction with partial least squares regression 被引量:2
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作者 Liu Zunxiong Liu Jianhui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期611-615,共5页
Considering chaotic time series multi-step prediction, multi-step direct prediction model based on partial least squares (PLS) is proposed in this article, where PLS, the method for predicting a set of dependent var... Considering chaotic time series multi-step prediction, multi-step direct prediction model based on partial least squares (PLS) is proposed in this article, where PLS, the method for predicting a set of dependent variables forming a large set of predictors, is used to model the dynamic evolution between the space points and the corresponding future points. The model can eliminate error accumulation with the common single-step local model algorithm~ and refrain from the high multi-collinearity problem in the reconstructed state space with the increase of embedding dimension. Simulation predictions are done on the Mackey-Glass chaotic time series with the model. The satisfying prediction accuracy is obtained and the model efficiency verified. In the experiments, the number of extracted components in PLS is set with cross-validation procedure. 展开更多
关键词 chaotic series prediction multi-step local model partial least squares.
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Modeling of forest soil and litter health using disturbance and landscape heterogeneity indicators in northern Iran 被引量:1
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作者 Malihe ERFANI Abdolrassoul SALMANMAHINY +1 位作者 Afshin DANEHKAR Vahid ETEMAD 《Journal of Mountain Science》 SCIE CSCD 2017年第9期1801-1813,共13页
This paper focuses on the indicators of soil and litter health, disturbance, and landscape heterogeneity as a tool for prediction of ecosystem sustainability in the northern forests of Iran. The study area was divided... This paper focuses on the indicators of soil and litter health, disturbance, and landscape heterogeneity as a tool for prediction of ecosystem sustainability in the northern forests of Iran. The study area was divided into spatial homogenous sites using slope, aspect, and soil humidity classes. Then a range of sites along the disturbance gradient was selected for sampling. Chemical and physical indicators of soil and litter health were measured at random points within these sites. Structural equation modeling(SEM) was applied to link six constructs of landscape heterogeneity, three constructs of disturbance(harvest, livestock, and human accessibility), and soil and litter health. The results showed that with decreasing accessibility, the total N and organic matter content of soil increased and effective bulk density decreased. Harvesting activities increased soil organic matter. Therefore, it is concluded that disturbances through harvesting and accessibility inversely affect the soil health. Unexpectedly, it was found that the litter total C and C:N ratio improved with an increase in the harvest and accessibility disturbances, whereas litter bulk density decreased. Investigation of tree composition revealed that in the climax communities, which are normally affected more by harvesting activities, some species like Fagus orientalis Lipsky with low decomposition rate are dominant. The research results showed that changes in disturbance intensity are reflected in litter and soil indicators, whereas the SEM indicated that landscape heterogeneity has a moderator effect on the disturbance to both litter and soil paths. 展开更多
关键词 Soil health forest litter Structural equation modeling(SEM) partial least squares(PLS) Ecosystem approach Northern Iran
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On the Decision Structures and Knowledge Discovery for ANP Modeling
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作者 Lawrence W. Lan Wei-Wen Wu Yu-Ting Lee 《International Journal of Intelligence Science》 2013年第1期15-23,共9页
This paper proposes an integrative framework for network-structured analytic network process (ANP) modeling. The underlying rationales include: 1) creating the measuring items for the complex decision problems;2) appl... This paper proposes an integrative framework for network-structured analytic network process (ANP) modeling. The underlying rationales include: 1) creating the measuring items for the complex decision problems;2) applying factor analysis to reduce the complex measuring items into fewer constructs;3) employing Bayesian network classifier technique to discover the causal directions among constructs;4) using partial least squares path modeling to test the causal relationships among the items-constructs. The proposed framework is implemented for knowledge discovery to a case of high-tech companies’ enterprise resource planning (ERP) benefits and satisfaction in Hsinchu Science Park,Taiwan. The results show that the proposed framework for ANP modeling can reach a satisfactory level of convergent reliability and validity. Based on the findings, pragmatic implications to the ERP venders are discussed. This study has shed new light on the long neglected, yet critical, issue on decision structures and knowledge discovery for ANP modeling. 展开更多
关键词 ANALYTIC NETWORK Process BAYESIAN NETWORK CLASSIFIER Enterprise RESOURCE Planning Knowledge Discovery partial least squares path modeling
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Evaluation model for freeway incident management system 被引量:2
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作者 何锭 倪富健 杨顺新 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期126-131,共6页
In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evalu... In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evaluation index. As a result, 81 indices and the hierarchical structures of the index such as the object layer, the sub-object layer, the criterion layer and the index layer are determined. Then, based on the fuzzy characteristics of each index layer, the analytical hierarchy process(AHP)and the fuzzy comprehensive evaluation are applied to generate the weight and the satisfaction of the index and the criterion layers. When analyzing the relationship between the sub-object layer and the object layer, it is easy to find that the number of sub-objects is too large and sub-objects are significantly redundant. The partial least square (PLS) is proposed to solve the problems. Finally, an application example, whose result has already been accepted and employed as the indication of a new project in improving incident management, is introduced and the result verifies the feasibility and efficiency of the model. 展开更多
关键词 freeway incident management system evaluation model analytical hierarchical process fuzzy comprehensive evaluations partial least square
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The Consistency of LSE Estimators in Partial Linear Regression Models under Mixing Random Errors
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作者 Yun Bao YAO Yu Tan LÜ +2 位作者 Chao LU Wei WANG Xue Jun WANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第5期1244-1272,共29页
In this paper,we consider the partial linear regression model y_(i)=x_(i)β^(*)+g(ti)+ε_(i),i=1,2,...,n,where(x_(i),ti)are known fixed design points,g(·)is an unknown function,andβ^(*)is an unknown parameter to... In this paper,we consider the partial linear regression model y_(i)=x_(i)β^(*)+g(ti)+ε_(i),i=1,2,...,n,where(x_(i),ti)are known fixed design points,g(·)is an unknown function,andβ^(*)is an unknown parameter to be estimated,random errorsε_(i)are(α,β)-mix_(i)ng random variables.The p-th(p>1)mean consistency,strong consistency and complete consistency for least squares estimators ofβ^(*)and g(·)are investigated under some mild conditions.In addition,a numerical simulation is carried out to study the finite sample performance of the theoretical results.Finally,a real data analysis is provided to further verify the effect of the model. 展开更多
关键词 β)-mixing random variables partial linear regression model least squares estimator CONSISTENCY
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Modeling of UAV path planning based on IMM under POMDP framework 被引量:4
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作者 YANG Qiming ZHANG Jiandong SHI Guoqing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第3期545-554,共10页
In order to enhance the capability of tracking targets autonomously of unmanned aerial vehicle (UAV), the partially observable Markov decision process (POMDP) model for UAV path planning is established based on the PO... In order to enhance the capability of tracking targets autonomously of unmanned aerial vehicle (UAV), the partially observable Markov decision process (POMDP) model for UAV path planning is established based on the POMDP framework. The elements of the POMDP model are analyzed and described. The state transfer law in the model can be described by the method of interactive multiple model (IMM) due to the diversity of the target motion law, which is used to switch the motion model to accommodate target maneuvers, and hence improving the tracking accuracy. The simulation results show that the model can achieve efficient planning for the UAV route, and effective tracking for the target. Furthermore, the path planned by this model is more reasonable and efficient than that by using the single state transition law. 展开更多
关键词 partialLY OBSERVABLE MARKOV decision process (POMDP) interactive multiple model (IMM) filtering path planning target tracking state transfer law
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MIMO Soft-sensor Model of Nutrient Content for Compound Fertil- izer Based on Hybrid Modeling Technique 被引量:6
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作者 傅永峰 苏宏业 褚健 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期554-559,共6页
In compound fertilizer production, several quality variables need to be monitored and controlled simultaneously. It is very diifficult to measure these variables on-line by existing instruments and sensors. So, soft-s... In compound fertilizer production, several quality variables need to be monitored and controlled simultaneously. It is very diifficult to measure these variables on-line by existing instruments and sensors. So, soft-sensor technique becomes an indispensable method to implement real-time quality control. In this article, a new model of multi-inputs multi-outputs (MIMO) soft-sensor, which is constructed based on hybrid modeling technique, is proposed for these interactional variables. Data-driven modeling method and simplified first principle modelingmethod are combined in this model. Data-driven modeling method based on limited memory partial least squares(LM-PLS) al.gorithm is used to build soft-senor models for some secondary variables.then, the simplified first principle model is used to compute three primary variables on line. The proposed model has been used in practicalprocess; the results indicate that the proposed model is precise and efficient, and it is possible to realize on line quality control for compound fertilizer process. 展开更多
关键词 multi-inputs multi-outputs soft-sensor limited memory partial least squares simplified first principle model nutrient content of compound fertilizer
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Comparative Study on Deformation Prediction Models of Wuqiangxi Concrete Gravity Dam Based on Monitoring Data 被引量:1
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作者 Songlin Yang Xingjin Han +3 位作者 Chufeng Kuang Weihua Fang Jianfei Zhang Tiantang Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第4期49-72,共24页
The deformation prediction models of Wuqiangxi concrete gravity dam are developed,including two statistical models and a deep learning model.In the statistical models,the reliable monitoring data are firstly determine... The deformation prediction models of Wuqiangxi concrete gravity dam are developed,including two statistical models and a deep learning model.In the statistical models,the reliable monitoring data are firstly determined with Lahitte criterion;then,the stepwise regression and partial least squares regression models for deformation prediction of concrete gravity dam are constructed in terms of the reliable monitoring data,and the factors of water pressure,temperature and time effect are considered in the models;finally,according to the monitoring data from 2006 to 2020 of five typical measuring points including J23(on dam section 24^(#)),J33(on dam section 4^(#)),J35(on dam section 8^(#)),J37(on dam section 12^(#)),and J39(on dam section 15^(#))located on the crest of Wuqiangxi concrete gravity dam,the settlement curves of the measuring points are obtained with the stepwise regression and partial least squares regression models.A deep learning model is developed based on long short-term memory(LSTM)recurrent neural network.In the LSTM model,two LSTMlayers are used,the rectified linear unit function is adopted as the activation function,the input sequence length is 20,and the random search is adopted.The monitoring data for the five typical measuring points from 2006 to 2017 are selected as the training set,and the monitoring data from 2018 to 2020 are taken as the test set.From the results of case study,we can find that(1)the good fitting results can be obtained with the two statistical models;(2)the partial least squares regression algorithm can solve the model with high correlation factors and reasonably explain the factors;(3)the prediction accuracy of the LSTM model increases with increasing the amount of training data.In the deformation prediction of concrete gravity dam,the LSTM model is suggested when there are sufficient training data,while the partial least squares regression method is suggested when the training data are insufficient. 展开更多
关键词 Wuqiangxi concrete gravity dam deformation prediction stepwise regression model partial least squares regression model LSTM model
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Selective ensemble modeling based on nonlinear frequency spectral feature extraction for predicting load parameter in ball mills 被引量:3
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作者 汤健 柴天佑 +1 位作者 刘卓 余文 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第12期2020-2028,共9页
Strong mechanical vibration and acoustical signals of grinding process contain useful information related to load parameters in ball mills. It is a challenge to extract latent features and construct soft sensor model ... Strong mechanical vibration and acoustical signals of grinding process contain useful information related to load parameters in ball mills. It is a challenge to extract latent features and construct soft sensor model with high dimensional frequency spectra of these signals. This paper aims to develop a selective ensemble modeling approach based on nonlinear latent frequency spectral feature extraction for accurate measurement of material to ball volume ratio. Latent features are first extracted from different vibrations and acoustic spectral segments by kernel partial least squares. Algorithms of bootstrap and least squares support vector machines are employed to produce candidate sub-models using these latent features as inputs. Ensemble sub-models are selected based on genetic algorithm optimization toolbox. Partial least squares regression is used to combine these sub-models to eliminate collinearity among their prediction outputs. Results indicate that the proposed modeling approach has better prediction performance than previous ones. 展开更多
关键词 Nonlinear latent feature extraction Kernel partial least squares Selective ensemble modeling least squares support vector machines Material to ball volume ratio
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Validation of general linear modeling for identifying factors associated with Quality of Life: A comparison with structural equation modeling
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作者 Naoko Kumagai Motonori Hatta +1 位作者 Yashiyasu Okuhara Hideki Origasa 《Health》 2013年第11期1884-1888,共5页
Purpose: General linear modeling (GLM) is usually applied to investigate factors associated with the domains of Quality of Life (QOL). A summation score in a specific sub-domain is regressed by a statistical model inc... Purpose: General linear modeling (GLM) is usually applied to investigate factors associated with the domains of Quality of Life (QOL). A summation score in a specific sub-domain is regressed by a statistical model including factors that are associated with the sub-domain. However, using the summation score ignores the influence of individual questions. Structural equation modeling (SEM) can account for the influence of each question’s score by compositing a latent variable from each question of a sub-domain. The objective of this study is to determine whether a conventional approach such as GLM, with its use of the summation score, is valid from the standpoint of the SEM approach. Method: We used the Japanese version of the Maugeri Foundation Respiratory Failure Questionnaire, a QOL measure, on 94 patients with heart failure. The daily activity sub-domain of the questionnaire was selected together with its four accompanying factors, namely, living together, occupation, gender, and the New York Heart Association’s cardiac function scale (NYHA). The association level between individual factors and the daily activity sub-domain was estimated using SEM?and GLM, respectively. The standard partial regression coefficients of GLM and standardized path coefficients of SEM were compared. If?these coefficients were similar (absolute value of the difference -0.06 and -0.07 for the GLM and SEM. Likewise, the estimates of occupation, gender, and NYHA were -0.18 and -0.20, -0.08 and -0.08, 0.51 and 0.54, respectively. The absolute values of the difference for each factor were 0.01, 0.02, 0.00, and 0.03, respectively. All differences were less than 0.05. This means that these two approaches lead to similar conclusions. Conclusion: GLM is a valid method for exploring association factors with a domain in QOL. 展开更多
关键词 General LINER modelING LATENT Variable Standardized path COEFFICIENT Standard partial Regression COEFFICIENT Structural Equation modelING
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Theoretical Research on Scattering Resonance States of Reaction I+HI(v=O)→IH(v'=0)+I: Partial Potential Energy Surface and One-dimensional Quantum Reactive Scattering Calculation
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作者 Hua-yang Wang Xiao-min Sun +1 位作者 Zheng-ting Cai Da-cheng Feng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第5期411-415,共5页
Based on the vibrational potential curves coupled with the minimum energy reaction path, the partial potential energy surface of the reaction I+HI→IH+I was constructed at the QCISD(T)//MP4SDQ level with pseudo po... Based on the vibrational potential curves coupled with the minimum energy reaction path, the partial potential energy surface of the reaction I+HI→IH+I was constructed at the QCISD(T)//MP4SDQ level with pseudo potential method. And the formation mechanism of the scattering resonance states of this reaction was well interpreted with the partial potential energy surface. The scattering resonance states of this reaction should belong to Feshbach resonance because of the coupling of the vibrational mode and the translational mode. With the one-dimensional square potential well model, the resonance width and lifetime of the I+HI(v=0)→IH(v'=0)+I state-to-state reaction were calculated, which preferably explained the high-resolved threshold photodetachment spectroscopy of the IHI- anion performed by Neumark et al.. 展开更多
关键词 partial potential energy surface Scattering resonance states Scattering resonance width and lifetime One-dimensional square potential well model
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发酵玉米芯多糖、还原糖含量近红外模型的建立
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作者 张燕 王园 +5 位作者 杜涓 李施垚 郑越 王春媛 齐景伟 安晓萍 《中国饲料》 北大核心 2024年第7期101-108,共8页
本实验旨在应用近红外光谱技术(NIRS)结合化学计量学法快速预测发酵玉米芯中多糖、还原糖含量,为定量检测发酵玉米芯多糖、还原糖含量提供理论依据以及为玉米芯深加工利用提供技术支持。以105份微生物发酵的玉米芯为供试材料,采用苯酚-... 本实验旨在应用近红外光谱技术(NIRS)结合化学计量学法快速预测发酵玉米芯中多糖、还原糖含量,为定量检测发酵玉米芯多糖、还原糖含量提供理论依据以及为玉米芯深加工利用提供技术支持。以105份微生物发酵的玉米芯为供试材料,采用苯酚-硫酸法和DNS法分别测定多糖和还原糖含量。利用偏最小二乘法(PLS),通过不同预处方式和不同波长建立发酵玉米芯多糖、还原糖含量的近红外分析模型。结果表明:多糖模型采用标准正态变量变换(SNV)+1阶导数的方法对全谱图进行预处理的效果较好,优化后的模型决定系数(R2)、校正均方根误差(RMSEC)、校准标准差(SEC)分别为0.82、9.28、9.34,其相对分析误差(PRD)为2.37;还原糖模型采用1阶导数+标准正态变量变换(SNV)+去趋势化(Detrend)的方法对全谱图进行预处理的效果较好,优化后的模型决定系数(R2)、校正均方根误差(RMSEC)、校准标准差(SEC)分别为0.84、4.03、4.04,其相对分析误差(PRD)为2.48;预测集决定系数分别为0.85、0.88。本研究构建的NIRS模型校正和交互验证决定系数均较大,相对分析误差均大于2,说明模型预测性能较好,建立的模型有助于发酵玉米芯多糖、还原糖含量活性成分的筛选。 展开更多
关键词 玉米芯 多糖 还原糖 近红外模型 偏最小二乘法
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公共管理硕士研究生知识转移影响因素分析
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作者 韦惠惠 《管理现代化》 北大核心 2024年第3期139-148,共10页
文章旨在探究公共管理硕士研究生知识转移的影响因素及作用机理。基于已有文献构建假设模型,借助问卷调查数据,采用偏最小二乘法结构方程建模方法(PLS-SEM)对假设模型进行验证。研究发现:转移动机对项目知识转移有显著正向影响,且在转... 文章旨在探究公共管理硕士研究生知识转移的影响因素及作用机理。基于已有文献构建假设模型,借助问卷调查数据,采用偏最小二乘法结构方程建模方法(PLS-SEM)对假设模型进行验证。研究发现:转移动机对项目知识转移有显著正向影响,且在转移过程中发挥中介作用;学习结果对项目知识转移有显著正向影响,学习结果、感知内容效度通过转移动机对项目知识转移产生间接影响;使用机会对项目知识转移有显著正向影响,主管支持分别经由转移动机、使用机会对项目知识转移产生间接影响。基于研究结果提出实践建议:激发公共管理硕士研究生的知识转移动机;优化公共管理硕士教育项目的内容和形式;加强公共部门主管支持,创造更多使用机会。 展开更多
关键词 公共管理硕士研究生 知识转移 偏最小二乘法结构方程模型
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城镇化对长江经济带农业碳排放的影响及其耦合关系研究
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作者 耿亮 彭灵通 +1 位作者 魏玻 安彧 《生态经济》 北大核心 2024年第3期128-138,共11页
基于区域一体化视角,使用长江经济带2000—2020年面板数据,多维度构建城镇化和农业碳排放指标体系,结合层次分析法和熵值法进行指标赋权,采用偏最小二乘法与耦合协调度模型定量分析二者的影响机制和耦合关系。结果表明:(1)城镇化主导类... 基于区域一体化视角,使用长江经济带2000—2020年面板数据,多维度构建城镇化和农业碳排放指标体系,结合层次分析法和熵值法进行指标赋权,采用偏最小二乘法与耦合协调度模型定量分析二者的影响机制和耦合关系。结果表明:(1)城镇化主导类型呈现人口城镇化→空间城镇化→生态环境城镇化→经济城镇化→社会城镇化发展趋势。(2)农业碳排放空间差异显著,等级演变明显,唯安徽省和上海市一直处于最高级和最低级。(3)人口、经济、社会、生态环境城镇化是影响农业碳排放的四个重要维度,人均国内生产总值、人均教育经费、万元GDP能耗等7项指标是极重要因素。(4)城镇化与农业碳排放耦合关系呈增长态势,耦合度从磨合转向高水平耦合,耦合协调度由勉强协调发展为良好协调,说明二者共振性良好,趋于协调发展。 展开更多
关键词 城镇化 农业碳排放 偏最小二乘法 耦合协调度模型 长江经济带
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近30年皖西大别山土壤侵蚀时空变化及其对景观格局的响应 被引量:1
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作者 田昌园 张红丽 +3 位作者 汪军红 李嘉宁 张艺 查同刚 《水土保持学报》 CSCD 北大核心 2024年第3期37-44,共8页
[目的]为明确安徽省内长江流域和淮河流域重要的生态过渡区皖西大别山区的景观格局与土壤侵蚀及其关系,为该区域的景观格局调控和水土流失治理提供参考。[方法]借助RULSE模型计算皖西大别山区近30年土壤侵蚀模数,借助景观指数对其景观... [目的]为明确安徽省内长江流域和淮河流域重要的生态过渡区皖西大别山区的景观格局与土壤侵蚀及其关系,为该区域的景观格局调控和水土流失治理提供参考。[方法]借助RULSE模型计算皖西大别山区近30年土壤侵蚀模数,借助景观指数对其景观格局的变化进行描述,并使用偏最小二乘回归(PLSR)探究该区域景观指数对土壤侵蚀的影响关系。[结果]近30年,土壤侵蚀模数呈先减少后增加趋势;土壤侵蚀较严重地区主要集中在中西部和南部山区;大部分地区土壤侵蚀强度主要为微度和轻度,且各类土地利用类型的侵蚀强度有明显差别,表现为草地>耕地>林地;土地利用类型及景观格局总体较稳定,景观格局变化主要表现为景观破碎化的降低、景观异质性和连接性的提高;香农多样性指数(SHDI)、边界密度指数(ED)、相似邻近百分比(PLADJ)、景观形状指数(LSI)对皖西大别山区具有显著解释意义,且表现为SHDI、ED、LSI对土壤侵蚀起显著正向作用,PLADJ对土壤侵蚀起显著负向作用。[结论]在皖西大别山区,景观破碎化的提高和景观连通度的降低显著促进土壤侵蚀。 展开更多
关键词 土壤侵蚀 景观格局 RULSE模型 偏最小二乘回归
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