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PARAMETER ESTIMATION OF MULTI-CONSTITUENT WATER QUALITY MODEL FOR THE LIANGXI RIVER BY MARQUARDT METHOD
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作者 Liu Shuxia(Institute of Geography, CAS, Beijing 100101People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1994年第Z1期110-118,共9页
A multi-constituent water quality model is presented,Which relates carbonaceous biochemical oxygen demand (CBOD),amonia (NH3-N), nitrite(NO2-N), nitrate(NO3-N) and dissolvedoxygen(DO). The parameters are solved by Mar... A multi-constituent water quality model is presented,Which relates carbonaceous biochemical oxygen demand (CBOD),amonia (NH3-N), nitrite(NO2-N), nitrate(NO3-N) and dissolvedoxygen(DO). The parameters are solved by Marquardt Method (i. e.,Dampled Least Square Method) while initial values inoptimization are produced by Monte-Carlo Method. The Potential ofthe method as a parameter estimation aid is demonstrated for theapplication to the Liangyi Rver, JiangSu Province of China and by aspecial comparison with Gauss Method. 展开更多
关键词 nitrogen pollution water quality model parameter estimation Marquardt Method Monte-Carlo Method
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ON THE ESTIMATION OF SURFACE ALBEDO USING SATELLITE DATE
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作者 Fang Xianjin(Dept. of Environmental Engineering, Tsinghua University, Beijing 100084People’s Republic of China)Zhang Ying(National Meteorological Center, Beijing 100081People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1995年第2期59-76,共18页
The method to determine the surface albedo using satellite date hasbeen developed and discussed. The relatons betwam the planetary albedo andsurfoce albedo in clear skies are derived with the help of the radiative ... The method to determine the surface albedo using satellite date hasbeen developed and discussed. The relatons betwam the planetary albedo andsurfoce albedo in clear skies are derived with the help of the radiative transfermodelling. To improve the accuracy of the denved surfoce albedo, theparameter X0, i.e., the ratio of the reflected to the total extinction radiation isintroduced into this model. The influences of the model paramenters on thesurfoce albedo have been analyzed. It is found that the error in the derivedsurfoce albedo due to the paramaters together is less than that caused by oulyone parameter because of the complementarity of the parameters. Test resultsin 22 stations over China have been given using the Geostationary SatelliteGMS. The results are generally agreeable except for the case of snow/ice cover. 展开更多
关键词 surface albedo satellite date model parameter estimation
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A new generic reaction for modeling fluid catalytic cracking risers
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作者 Yong Li Jizheng Chu Jiarui Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第10期1449-1460,共12页
A new generic reaction in the form of PC_i→PC_m+[i,m]→PC_m+λi,m coke+surplusage has been proposed for describing the catalytic cracking behavior of petroleum narrow cuts or pseudo-components(PCs),where the rate con... A new generic reaction in the form of PC_i→PC_m+[i,m]→PC_m+λi,m coke+surplusage has been proposed for describing the catalytic cracking behavior of petroleum narrow cuts or pseudo-components(PCs),where the rate constant formula is derived from the transition state theory and the coking amount is correlated to the properties of the intermediate substance [i,m].In composing the cracking reaction network for feedstock and product oils,only the product PC m of the proposed generic reaction is used,which together with a criterion for excluding exothermic reactions,distinctly reduces the number of reactions in the network.With the proposed cracking reaction scheme coupled with special pseudo-components,a predictive one-dimensional steady state model for fluid catalytic cracking risers is formulated in the sense that for a given riser and given catalyst,the model parameters are independent of stock oils,product schemes and other operational conditions.The great correlating and predicting capability of the resulted model is tested with production data in different scenarios of four commercial risers. 展开更多
关键词 Fluid catalytic cracking riser Kinetic modeling Pseudo-component Petroleum Steady state model parameter estimation
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ON THE STABILITY OF THE SOLUTION TO A GONORRHEA DISCRETE MATHEMATICAL MODEL
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作者 金均 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第6期545-550,共6页
In this paper, the author studies the stability of the solution to a three-dimension-al gonorrhea discrete mathematical model by Liapunoy method. The parameter es-timator of the slability domain is obtained and the ra... In this paper, the author studies the stability of the solution to a three-dimension-al gonorrhea discrete mathematical model by Liapunoy method. The parameter es-timator of the slability domain is obtained and the rationality of the model is ex-plained in a theoretic way. 展开更多
关键词 GONORRHEA discrete mathematical model. parameter estimator.stability domain
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Parameter Estimation of S-Shaped Growth Model:A Modified Particle Swarm Algorithm
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作者 XU Xing WEI Bo +2 位作者 WU Yu LIU Bingxiang LI Yuanxiang 《Wuhan University Journal of Natural Sciences》 CAS 2012年第2期137-143,共7页
Parameter estimation plays a critical role for the application and development of S-shaped growth model in the agricultural sciences and others.In this paper,a modified particle swarm optimization algorithm based on t... Parameter estimation plays a critical role for the application and development of S-shaped growth model in the agricultural sciences and others.In this paper,a modified particle swarm optimization algorithm based on the diffusion phenomenon(DPPSO) was employed to estimate the parameters for this model.Under the sense of least squares,the parameter estimation problem of S-shaped growth model,taking the Gompertz and Logistic models for example,is transformed into a multi-dimensional function optimization problem.The results show that the DPPSO algorithm can effectively estimate the parameters of the S-shaped growth model. 展开更多
关键词 particle swarm optimization diffusion phenomenon parameter estimation S-shaped growth model
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Combined forecast method of HMM and LS-SVM about electronic equipment state based on MAGA 被引量:1
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作者 Jianzhong Zhao Jianqiu Deng +1 位作者 Wen Ye Xiaofeng Lü 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第3期730-738,共9页
For the deficiency that the traditional single forecast methods could not forecast electronic equipment states, a combined forecast method based on the hidden Markov model(HMM) and least square support vector machin... For the deficiency that the traditional single forecast methods could not forecast electronic equipment states, a combined forecast method based on the hidden Markov model(HMM) and least square support vector machine(LS-SVM) is presented. The multi-agent genetic algorithm(MAGA) is used to estimate parameters of HMM to overcome the problem that the Baum-Welch algorithm is easy to fall into local optimal solution. The state condition probability is introduced into the HMM modeling process to reduce the effect of uncertain factors. MAGA is used to estimate parameters of LS-SVM. Moreover, pruning algorithms are used to estimate parameters to get the sparse approximation of LS-SVM so as to increase the ranging performance. On the basis of these, the combined forecast model of electronic equipment states is established. The example results show the superiority of the combined forecast model in terms of forecast precision,calculation speed and stability. 展开更多
关键词 parameter estimation hidden Markov model(HMM) least square support vector machine(LS-SVM) multi-agent genetic algorithm(MAGA) state forecast
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On the Analysis Method of the Triple Test Cross Design
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作者 Jin Yi(Northeast Agricultural University, Harbin 1 50030, P R C) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1995年第1期66-74,共9页
The analysis method of the triple test cross design has been discussed carefully from the two factor experiment design and the genetic models of additive dominant effect and of epistasis effect.Two points different f... The analysis method of the triple test cross design has been discussed carefully from the two factor experiment design and the genetic models of additive dominant effect and of epistasis effect.Two points different from the previous reports have been concluded: (1)both the degrees of freedom of the orthogonal terms C2 and C3 are m, (2)the denominator in the F test to C2 and C3 is the error mean of square between plots. 展开更多
关键词 Triple test cross design Additive-dominant model Epistasis model Genetic parameter estimate.
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Study on Ground Deformation during Shield Tunnel Construction
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作者 Zhongkun Zhang 《Journal of Construction Research》 2021年第2期19-26,共8页
Through the systematic analysis of the ground settlement generated by the process of shield tunneling,the relationships between ground deformation and construction parameters are studied in this paper.Based on the ass... Through the systematic analysis of the ground settlement generated by the process of shield tunneling,the relationships between ground deformation and construction parameters are studied in this paper.Based on the assumption of linear small deformation,a mathematical model of the relationship between ground deformation and construction parameters is set up.The principle and method of optimization for estimating ground deformation is studied.The actual measured data are compared with the results of theoretical analysis in a case.Considering different ground formations in different construction sites with different adverse effects on surface and underground structures,the ground surface deformations caused by shield tunneling is an aimed topic in this paper.The contributions and research implications are the revealed relationships between the ground deformation and the shield tunneling parameters during construction. 展开更多
关键词 Shield tunnel Ground settlement Construction parameters Mathematical model Maximum estimation Shield tunnel Ground settlement Construction parameters Mathematical model Maximum estimation
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Probabilistic Assessment of Constitutive Model Parameters:Insight from a Statistical Damage Constitutive Model and a Simple Critical State Hypoplastic Model
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作者 Yang Xue Fasheng Miao +3 位作者 Yiping Wu Linwei Li Daniel Dias Yang Tang 《Journal of Earth Science》 2025年第2期685-699,共15页
The constitutive model is essential for predicting the deformation and stability of rocksoil mass.The estimation of constitutive model parameters is a necessary and important task for the reliable characterization of ... The constitutive model is essential for predicting the deformation and stability of rocksoil mass.The estimation of constitutive model parameters is a necessary and important task for the reliable characterization of mechanical behaviors.However,constitutive model parameters cannot be evaluated accurately with a limited amount of test data,resulting in uncertainty in the prediction of stress-strain curves.This paper proposes a Bayesian analysis framework to address this issue.It combines the Bayesian updating with the structural reliability and adaptive conditional sampling methods to assess the equation parameter of constitutive models.Based on the triaxial and ring shear tests on shear zone soils from the Huangtupo landslide,a statistical damage constitutive model and a critical state hypoplastic constitutive model were used to demonstrate the effectiveness of the proposed framework.Moreover,the parameter uncertainty effects of the damage constitutive model on landslide stability were investigated.Results show that reasonable assessments of the constitutive model parameter can be well realized.The variability of stress-strain curves is strongly related to the model prediction performance.The estimation uncertainty of constitutive model parameters should not be ignored for the landslide stability calculation.Our study provides a reference for uncertainty analysis and parameter assessment of the constitutive model. 展开更多
关键词 probabilistic back analysis Bayesian approach model parameter estimation constitutive model landslide stability engineering geology
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