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Calculation of Activity Coefficient from Immiscible Binary Alloy Phase Diagram by Means of Modified Sub-regular Solution Model 被引量:3
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作者 张兆春 吴铸 +2 位作者 曾文明 陈念贻 彭瑞伍 《Rare Metals》 SCIE EI CAS CSCD 1998年第3期34-38,共5页
The modified sub regular solution model was used for a calculation of the activity coefficient of immiscible binary alloy systems. The parameters needed for the calculation are the interaction parameters, λ 1 a... The modified sub regular solution model was used for a calculation of the activity coefficient of immiscible binary alloy systems. The parameters needed for the calculation are the interaction parameters, λ 1 and λ 2, which are represented as a linear function of temperature, T . The molar excess Gibbs free energy, G m E, can be written in the form G m E= x A x B[( λ 11 + λ 12 T )+( λ 21 + λ 22 T ) x B ] The calculation is carried out numerically for three immiscible binary alloy systems, Al Pb, Cu Tl and In V. The agreement between the calculated and experimentally determined values of activity coefficient is excellent. 展开更多
关键词 Modified sub regular solution model Activity coefficient Immiscible binary alloy system
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Application of Bayesian regularized BP neural network model for analysis of aquatic ecological data—A case study of chlorophyll-a prediction in Nanzui water area of Dongting Lake 被引量:5
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作者 XU Min ZENG Guang-ming +3 位作者 XU Xin-yi HUANG Guo-he SUN Wei JIANG Xiao-yun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第6期946-952,共7页
Bayesian regularized BP neural network(BRBPNN) technique was applied in the chlorophyll-α prediction of Nanzui water area in Dongting Lake. Through BP network interpolation method, the input and output samples of t... Bayesian regularized BP neural network(BRBPNN) technique was applied in the chlorophyll-α prediction of Nanzui water area in Dongting Lake. Through BP network interpolation method, the input and output samples of the network were obtained. After the selection of input variables using stepwise/multiple linear regression method in SPSS i1.0 software, the BRBPNN model was established between chlorophyll-α and environmental parameters, biological parameters. The achieved optimal network structure was 3-11-1 with the correlation coefficients and the mean square errors for the training set and the test set as 0.999 and 0.000?8426, 0.981 and 0.0216 respectively. The sum of square weights between each input neuron and the hidden layer of optimal BRBPNN models of different structures indicated that the effect of individual input parameter on chlorophyll- α declined in the order of alga amount 〉 secchi disc depth(SD) 〉 electrical conductivity (EC). Additionally, it also demonstrated that the contributions of these three factors were the maximal for the change of chlorophyll-α concentration, total phosphorus(TP) and total nitrogen(TN) were the minimal. All the results showed that BRBPNN model was capable of automated regularization parameter selection and thus it may ensure the excellent generation ability and robustness. Thus, this study laid the foundation for the application of BRBPNN model in the analysis of aquatic ecological data(chlorophyll-α prediction) and the explanation about the effective eutrophication treatment measures for Nanzui water area in Dongting Lake. 展开更多
关键词 Dongting Lake CHLOROPHYLL-A Bayesian regularized BP neural network model sum of square weights
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Subspace Minimization Conjugate Gradient Method Based on Cubic Regularization Model for Unconstrained Optimization 被引量:1
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作者 Ting Zhao Hongwei Liu 《Journal of Harbin Institute of Technology(New Series)》 CAS 2021年第5期61-69,共9页
Many methods have been put forward to solve unconstrained optimization problems,among which conjugate gradient method(CG)is very important.With the increasing emergence of large⁃scale problems,the subspace technology ... Many methods have been put forward to solve unconstrained optimization problems,among which conjugate gradient method(CG)is very important.With the increasing emergence of large⁃scale problems,the subspace technology has become particularly important and widely used in the field of optimization.In this study,a new CG method was put forward,which combined subspace technology and a cubic regularization model.Besides,a special scaled norm in a cubic regularization model was analyzed.Under certain conditions,some significant characteristics of the search direction were given and the convergence of the algorithm was built.Numerical comparisons show that for the 145 test functions under the CUTEr library,the proposed method is better than two classical CG methods and two new subspaces conjugate gradient methods. 展开更多
关键词 cubic regularization model conjugate gradient method subspace technique unconstrained optimization
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Activity Calculation by Application of Sub-Regular Solution Model in Binary Oxide Systems 被引量:1
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作者 HOU Yan-qing XIE Gang +2 位作者 TAO Dong-ping LI Rong-xing YU Xiao-hua 《Journal of Iron and Steel Research International》 SCIE CAS CSCD 2012年第7期33-38,共6页
To confirm sub-regular solution model valid for predicting the activity of component in binary oxide systems, seven systems in the whole concentration and twelve systems presenting saturation concentration have been s... To confirm sub-regular solution model valid for predicting the activity of component in binary oxide systems, seven systems in the whole concentration and twelve systems presenting saturation concentration have been studied. The total average relative errors of component 1 and 2 are 3.2 % and 4.1% respectively by application of the sub-regular solution model into the systems within the whole concentration. However, the total average relative errors are 16 % and 1088 % in the systems presenting saturation concentration. The results show that sub-regular solu- tion model is not good for predicting the systems presenting saturation concentration, especially for the systems con- taining acidic or neutral oxide. The reason may be that the influence of the two types of oxide on the configuration is greater in binary oxide systems. These oxides can be present in the form of complex anion partly, Si-O, Al-O, Ti-O and so on, for example (SiO4)4-. That is contrary to sub-regular solution model which is supposed that the oxide systems consist of cation and O2-. But compared with regular solution model and quasi-regular solution model, sub- regular solution model is closer to the characteristics of actual solution and the calculated results are superior. 展开更多
关键词 sub-regular solution models binary oxide system activity
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Activity Calculation in Complex Metallurgical Molten Slag Systems Based on Regular Solution Model
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作者 HOU Yan-qing,XIE Gang,TAO Dong-ping,YU Xiao-hua,LI Rong-xing (Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,Yunnan,China) 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2012年第3期6-10,共5页
The activity of FetO is very important in ironmaking and steelmaking process. In order to predict the activ- ity of Fe, O and optimize the operation conditions in ironmaking and steelmaking process, by application of ... The activity of FetO is very important in ironmaking and steelmaking process. In order to predict the activ- ity of Fe, O and optimize the operation conditions in ironmaking and steelmaking process, by application of regular so lution model in molten slag systems, FeO-Fe2 O3-SIO2 ternary system, FeO-Fe2 O3-SiO2-CaO and FeO-Fe2 O3-SiO2-NiO quaternary systems have been studied by the chemical equilibrium between H2/H20 gas mixture and liquid slag con tained in solid iron. The values of interaction energy between cations concerning steelmaking slags have been deter- mined by application of ferric-ferrous iron equilibrium and iron-ferric iron equilibrium. And then the activity of Fe, O can be calculated. The results show that the relative error is 3.9% in FeO-Fe203-SiO2 system and 18% in FeO- Fe203-SiO2 CaO system. The prediction of activities of FetO in the systems are in good agreement with the measure- ments and the regular solution model is valid for predicting the activity of FetO in complex molten slags systems. The activity of Fe, O in FeO-Fe20a-NiO system have not been tested presently, and the calculated result can not be assessed. 展开更多
关键词 regular solution model metallurgical molten slag activity
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Occurrence Regularity and Prediction Model of Underground Pest Adults in Hangzhou District of China
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作者 Wang Daoze Hong Wenying +2 位作者 Wu Yanjun Wang Aijuan Wei Jiqian 《Plant Diseases and Pests》 CAS 2013年第1期1-6,27,共7页
To improve forecasting and sustained control level of underground pests, trapping quantity of underground pests (black cutworm,mole cricket and scar-ab) by lamps and their field dynamics in Hangzhou district from 20... To improve forecasting and sustained control level of underground pests, trapping quantity of underground pests (black cutworm,mole cricket and scar-ab) by lamps and their field dynamics in Hangzhou district from 2005 to 2011 were investigated in the paper. The results showed that different pests had obvious differences in population dynamic. The black cutworm (Agrotis ypsilon) had several damage peaks (late May, late June and late July) and the moth amount in early period was relatively high. The mole cricket ( Gryllotalpa africana) had two damage peaks (late May to early July, early September to mid and late October). The scarab (Anomala corpulenta) had one damage peak (late May to late June). There were periodic changes in total quantity of underground pests among years, and the peak period appeared in the year of 2005, 2007 to 2009 and 2011, respectively. On this basis, temperature, humidity, rainfall and light were used as forecas- ting factors, using the method of stepwise regression, 19 factors with significant correlation were screened out and prediction models for occurrence quantity and oc- currence period of the three pests were established. By using accuracy degree judge model for verification, the score values of prediction model for occurrence quan-tity and occurrence period of the three underground pests were more than 58 and 70, which indicated that the historical coincident rate and prediction accuracy of estabhshed prediction models were good. 展开更多
关键词 Hangzhou district Underground pests Population dynamic Occurrence regularity Prediction model
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Application of Modified Quasi-Regular Solution Model to Binary Metallurgical Molten Slag Systems
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作者 HOU Yan-qing XIE Gang TAO Dong-ping YU Xiao-hua 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2010年第10期13-17,22,共6页
Modified quasi-regular solution model has been available based on the sub-regular solution model and quasiregular solution model in this article. The three parameters of this model are set by the computer-aided analys... Modified quasi-regular solution model has been available based on the sub-regular solution model and quasiregular solution model in this article. The three parameters of this model are set by the computer-aided analysis based on the experimental data of activity at two different temperatures. Seven binary molten slag systems in the whole concentration are calculated by application of the model and the average relative error is within 10%. Ten binary molten slag systems presenting saturation concentration are also calculated, but the average relative error is bigger, especially for the systems containing acidic oxide and neutral oxide. The results show that the calculated results are superior to those calculated by application of regular solution model, sub-regular solution model and quasi-regular solution model. 展开更多
关键词 ACTIVITY binary molten slag modified model sub-regular solution
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Some Properties of a Recursive Procedure for High Dimensional Parameter Estimation in Linear Model with Regularization
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作者 Hong Son Hoang Remy Baraille 《Open Journal of Statistics》 2014年第11期921-932,共12页
Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed t... Theoretical results related to properties of a regularized recursive algorithm for estimation of a high dimensional vector of parameters are presented and proved. The recursive character of the procedure is proposed to overcome the difficulties with high dimension of the observation vector in computation of a statistical regularized estimator. As to deal with high dimension of the vector of unknown parameters, the regularization is introduced by specifying a priori non-negative covariance structure for the vector of estimated parameters. Numerical example with Monte-Carlo simulation for a low-dimensional system as well as the state/parameter estimation in a very high dimensional oceanic model is presented to demonstrate the efficiency of the proposed approach. 展开更多
关键词 Linear model regularIZATION RECURSIVE Algorithm Non-Negative COVARIANCE Structure EIGENVALUE Decomposition
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Investigation of the Tikhonov Regularization Method in Regional Gravity Field Modeling by Poisson Wavelets Radial Basis Functions 被引量:2
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作者 Yihao Wu Bo Zhong Zhicai Luo 《Journal of Earth Science》 SCIE CAS CSCD 2018年第6期1349-1358,共10页
The application of Tikhonov regularization method dealing with the ill-conditioned problems in the regional gravity field modeling by Poisson wavelets is studied. In particular, the choices of the regularization matri... The application of Tikhonov regularization method dealing with the ill-conditioned problems in the regional gravity field modeling by Poisson wavelets is studied. In particular, the choices of the regularization matrices as well as the approaches for estimating the regularization parameters are investigated in details. The numerical results show that the regularized solutions derived from the first-order regularization are better than the ones obtained from zero-order regularization. For cross validation, the optimal regularization parameters are estimated from L-curve, variance component estimation(VCE) and minimum standard deviation(MSTD) approach, respectively, and the results show that the derived regularization parameters from different methods are consistent with each other. Together with the firstorder Tikhonov regularization and VCE method, the optimal network of Poisson wavelets is derived, based on which the local gravimetric geoid is computed. The accuracy of the corresponding gravimetric geoid reaches 1.1 cm in Netherlands, which validates the reliability of using Tikhonov regularization method in tackling the ill-conditioned problem for regional gravity field modeling. 展开更多
关键词 regional gravity field modeling Poisson wavelets radial basis functions Tikhonov regularization method L-CURVE variance component estimation(VCE)
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Iterative regularization method for image denoising with adaptive scale parameter
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作者 李文书 骆建华 +2 位作者 刘且根 何芳芳 魏秀金 《Journal of Southeast University(English Edition)》 EI CAS 2010年第3期453-456,共4页
In order to decrease the sensitivity of the constant scale parameter, adaptively optimize the scale parameter in the iteration regularization model (IRM) and attain a desirable level of applicability for image denoi... In order to decrease the sensitivity of the constant scale parameter, adaptively optimize the scale parameter in the iteration regularization model (IRM) and attain a desirable level of applicability for image denoising, a novel IRM with the adaptive scale parameter is proposed. First, the classic regularization item is modified and the equation of the adaptive scale parameter is deduced. Then, the initial value of the varying scale parameter is obtained by the trend of the number of iterations and the scale parameter sequence vectors. Finally, the novel iterative regularization method is used for image denoising. Numerical experiments show that compared with the IRM with the constant scale parameter, the proposed method with the varying scale parameter can not only reduce the number of iterations when the scale parameter becomes smaller, but also efficiently remove noise when the scale parameter becomes bigger and well preserve the details of images. 展开更多
关键词 iterative regularization model (IRM) total variation varying scale parameter image denoising
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生态鱼礁对规则波在珊瑚岛礁上传播变形与增水的影响
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作者 陈佳莹 任兴月 +1 位作者 屈科 王超 《应用海洋学学报》 北大核心 2026年第1期72-80,共9页
珊瑚礁海岸特殊的地貌结构可以对波浪起到天然缓冲作用,从而有效降低波浪对海岸的破坏,保护后方人口密集地区的安全。然而,岛礁上日益增多的人类活动,如吹填珊瑚砂和基建工程等,不但对珊瑚岛礁脆弱的生态系统构成威胁,并且显著重塑了岛... 珊瑚礁海岸特殊的地貌结构可以对波浪起到天然缓冲作用,从而有效降低波浪对海岸的破坏,保护后方人口密集地区的安全。然而,岛礁上日益增多的人类活动,如吹填珊瑚砂和基建工程等,不但对珊瑚岛礁脆弱的生态系统构成威胁,并且显著重塑了岛礁的波浪水动力环境,影响岸礁对海岸的保护作用。目前,岛礁建设面临生态修复和改善防浪抗浪特性的双重需要。本研究基于物理模型实验,系统研究了生态鱼礁存在时对珊瑚岛礁上规则波水动力特性影响的变化规律,分析了不同入射波高、礁坪水深、波浪周期和礁体开孔率等4种因素的影响,试验结果表明:生态鱼礁的存在会对规则波在岛礁上传播的演变特性和增水产生显著影响。入射波浪与人工鱼礁之间产生复杂的相互作用,生态鱼礁的存在可以显著地减小礁缘及礁坪附近的局部波高,并降低礁坪上的波浪增水。此外,生态鱼礁内部复杂的涡流场会耗散更多的波浪能量,导致礁后斜坡上最大波浪爬高降低,实现防浪护岸的作用。 展开更多
关键词 生态鱼礁 生态护岸 规则波 水动力特性 物理模型试验
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基于嵌入特征和稀疏矩阵的实体对齐方法
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作者 冯超文 耿程晨 刘英莉 《浙江大学学报(工学版)》 北大核心 2026年第2期379-387,454,共10页
多语言知识融合的实体对齐面临特征建模粒度不足、结构信息利用受限的挑战,为此提出融合多层次嵌入特征与稀疏矩阵传播机制的实体对齐方法.结合字符特征、词向量特征与邻域关系特征,构建统一的多维实体表示,增强实体的局部语义表达和结... 多语言知识融合的实体对齐面临特征建模粒度不足、结构信息利用受限的挑战,为此提出融合多层次嵌入特征与稀疏矩阵传播机制的实体对齐方法.结合字符特征、词向量特征与邻域关系特征,构建统一的多维实体表示,增强实体的局部语义表达和结构关联建模能力.基于关系嵌入构建稀疏邻接矩阵,结合特征归一化传播机制,实现信息在知识图谱中的稳定扩展与有效传递.为了进一步提升实体匹配的全局一致性,引入Sinkhorn正则化优化相似度矩阵,采用Hungarian算法执行最优实体对齐.所提方法在多个跨语言知识图谱数据集上的命中率和平均倒数排名评价指标上均有稳定性能表现,比代表性方法(如SNGA、EAMI)的竞争性强.该结果有效验证了所提方法的准确性与鲁棒性. 展开更多
关键词 知识图谱 实体对齐 多层次特征建模 稀疏矩阵传播 Sinkhorn正则化
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THE BASIC CONSIDERATIONS OF SELF-SReM AND SELF-BoSS MODELS 被引量:1
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作者 G.C. Jiang K. Tang X.B. Zhang and K.D. Xu Shanghai Enhanced Laboratory of Ferrometallurgy, Shanghai University, 149 Yanchang Road, Shanghai 200072, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第4期988-994,共7页
Model Investigation is the only feasible way to solve the problem about the component activities in concentrated multicomponent alloys and molten slags at present. The basic characteristic of SELF-SReM model is brief... Model Investigation is the only feasible way to solve the problem about the component activities in concentrated multicomponent alloys and molten slags at present. The basic characteristic of SELF-SReM model is briefly introduced in this paper. It intends to give out the systematical value of component activities in the whole homogeneous region of a concentrated multicomponent melt, then to provide a reliable database for the description of the equilibrium conditions associated with metallurgy processes. For molten slags, the key issue is to distinguish the accuracy of thermodynamic properties in binary systems. The fundamental approach for this task is to link the microscopic bond structure and macroscopic activity based on both of the measurement of high tem- perature Raman spectroscopy and the corresponding computation simulation according to molecular dynamics and quantum chemistry. 展开更多
关键词 ACTIVITY sub-regular solution model structural model microscopic bond stucture
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Evaluation of Component Activities in C-Mn-Fe-Si with Model Self-SReM4 被引量:1
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作者 Zhang Xiaobing Jiang Guochang +1 位作者 Ding Weizhong Xu Kuangdi 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1998年第1期28-33,共6页
A sub-regular solution model SELFSReM4 used to evaluate activities of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Lab of Ferrometallurgy. This paper introduces... A sub-regular solution model SELFSReM4 used to evaluate activities of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Lab of Ferrometallurgy. This paper introduces the application of SELFSReM4 in evaluating activities of the components in C-Mn-Fe-Si system without SiC precipitation. 展开更多
关键词 sub-regular solution model component activity C-Mn-Si-Fe alloy
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Evaluation of Component Activity in Molten MnO-SiO_(2)-Al_(2)O_(3)-CaO System with Model SELF-SReM4 被引量:1
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作者 ZHANG Xiao-bing JIANG Guo-chang XU Kuang-di 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2000年第1期6-8,共3页
A sub-regular solution model SELF-SReM4 used to evaluate activity of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Laboratory of Ferrometallurgy.The application ... A sub-regular solution model SELF-SReM4 used to evaluate activity of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Laboratory of Ferrometallurgy.The application of SELF-SReM4 in C-Mn-Fe-Si system without the SiC formation has been introduced in previous paper.It’s application for molten slag of MnO-SiO2-Al2O3-CaO was introduced in this paper.They provide a basis for the prediction of the metal-slag equilibrium conditions. 展开更多
关键词 sub-regular solution model component activity m olten slag MnO-SiO2-Al2O3-CaO
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Two-dimensional regularized inversion of AMT data based on rotation invariant of Central impedance tensor 被引量:4
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作者 XiaoZhong Tong JianXin Liu AiYong Li 《Earth and Planetary Physics》 2018年第5期430-437,共8页
Considering the uncertainty of the electrical axis for two-dimensional audo-magnetotelluric(AMT) data processing, an AMT inversion method with the Central impedance tensor was presented. First, we present a calculatio... Considering the uncertainty of the electrical axis for two-dimensional audo-magnetotelluric(AMT) data processing, an AMT inversion method with the Central impedance tensor was presented. First, we present a calculation expression of the Central impedance tensor in AMT, which can be considered as the arithmetic mean of TE-polarization mode and TM-polarization mode in the twodimensional geo-electrical model. Second, a least-squares iterative inversion algorithm is established, based on a smoothnessconstrained model, and an improved L-curve method is adopted to determine the best regularization parameters. We then test the above inversion method with synthetic data and field data. The test results show that this two-dimensional AMT inversion scheme for the responses of Central impedance is effective and can reconstruct reasonable two-dimensional subsurface resistivity structures. We conclude that the Central impedance tensor is a useful tool for two-dimensional inversion of AMT data. 展开更多
关键词 audio-magnetotelluric/AMT impedance tensor rotation invariants two-dimensional geo-electrical model regularized inversion
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Inversion of dispersion coeffcient in water quality model using optimal perturbation algorithm 被引量:1
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作者 聂红涛 陶建华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第6期703-712,共10页
As a primary parameter in the water quality model for shallow bays, the dispersion coefficient is traditionally determined with a trial-and-error method, which is time-consuming and requires much experience. In this p... As a primary parameter in the water quality model for shallow bays, the dispersion coefficient is traditionally determined with a trial-and-error method, which is time-consuming and requires much experience. In this paper, based on the measured data of chemical oxygen demand (COD), the dispersion coefficient is calculated using an inversion method. In the process, the regularization method is applied to treat the ill-posedness, and an operator identity perturbation method is used to obtain the solu- tion. Using the model with an inverted dispersion coefficient, the distributions of COD, inorganic nitrogen (IN), and inorganic phosphorus (IP) in Bohai Bay are predicted and compared with the measured data. The results indicate that the method is feasible and the inverted dispersion coefficient can be used to predict other pollutant distribution. This method may also be further extended to the inversion of other parameters in the water quality model. 展开更多
关键词 water quality model dispersion coefficient INVERSION regularIZATION BohaiBay
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Composition Analysis and Identification of Ancient Glass Products Based on L1 Regularization Logistic Regression
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作者 Yuqiao Zhou Xinyang Xu Wenjing Ma 《Applied Mathematics》 2024年第1期51-64,共14页
In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluste... In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluster analysis, hyper-parameter test and other models, and SPSS, Python and other tools were used to obtain the classification rules of glass products under different fluxes, sub classification under different chemical compositions, hyper-parameter K value test and rationality analysis. Research can provide theoretical support for the protection and restoration of ancient glass relics. 展开更多
关键词 Glass Composition L1 regularization Logistic Regression model K-Means Clustering Analysis Elbow Rule Parameter Verification
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Epidemic Regularity and Control Effect of Huanglongbing (HLB) in Different Management Approaches
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作者 Yu Jihua Wang Enguo +2 位作者 Lu Lu Zhang Minrong Tao Jian 《Plant Diseases and Pests》 CAS 2016年第2期7-10,14,共5页
In order to reveal the epidemic regularity of Huanglongbing (HLB) in different management approaches, different citrus production areas were selected between 2002 and 2012 to compare epidemic regularity of different... In order to reveal the epidemic regularity of Huanglongbing (HLB) in different management approaches, different citrus production areas were selected between 2002 and 2012 to compare epidemic regularity of different types and control effects of different management approaches with plant incidence rate. All survey data in 11 years were used to build a mathematical model, and epidemic evolution and control effects were quantitatively analyzed. The results indicated that diffusion and prevalence of HLB generally increased linearly. In naturally growing citrus orchards without artificial control, the annual diseased plant rate was 11.11%, and the epidemic diffusion model was y1 = 12. 24x - 1.382 8 ( n =9, r =0. 976 9 * * ). Under general prevention and control conditions, the annual diseased plant rate was 4.69%, the epidemic diffusion model was Y2 = 5. 449 8x - 1.603 5 ( n = 11, r =0. 974 9 * * ), and the control effect was 43.93% (22.93% - 55.04% ). In citrus orchards with integrated prevention and control, the epidemic diffusion model was Y3 = 0. 366 3x - 0. 342 2 ( n = 11, r = 0. 989 8 * * ), the control effect was 96.15% (94.95% -97.40% ), and the annual diseased plant rate was 0.31%. Thus, HLB is preventable and controllable as long as integrated prevention and control work is implemented well. 展开更多
关键词 Huanglongbing (HLB) Management approach Epidemic regularity Diffusion model Control effect
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Liver Segmentation in CT Images Based on DRLSE Model
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作者 黄永锋 齐萌 严加勇 《Journal of Donghua University(English Edition)》 EI CAS 2012年第6期493-496,共4页
Liver segmentation in CT images is an important step for liver volumetry and vascular evaluation in liver pre-surgical planning. In this paper, a segmentation method based on distance regularized level set evolution(D... Liver segmentation in CT images is an important step for liver volumetry and vascular evaluation in liver pre-surgical planning. In this paper, a segmentation method based on distance regularized level set evolution(DRLSE) model was proposed, which incorporated a distance regularization term into the conventional Chan-Vese (C-V) model. In addition, the region growing method was utilized to generate the initial liver mask for each slice, which could decrease the computation time for level-set propagation. The experimental results show that the method can dramatically decrease the evolving time and keep the accuracy of segmentation. The new method is averagely 15 times faster than the method based on conventional C-V model in segmenting a slice. 展开更多
关键词 liver segmentation distance regularized level set evolution (DRLSE) model Chan-Vese (C-V) model region growing
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