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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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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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波流作用下半潜式养殖平台水动力特性物理模型试验
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作者 宋峥嵘 唐鸣夫 +4 位作者 胡性涛 刘俊斐 梅华东 郑振钧 杨传东 《渔业现代化》 北大核心 2025年第3期53-61,共9页
半潜式平台在无遮蔽海况下面临波流联合作用引发的系泊失效与运动失稳风险。针对可升降式养殖平台设计方案,通过物理模型试验校核其在维修、漂浮、坐底三类典型工况下的水动力性能。试验采用1∶75缩尺模型,测量平台6自由度运动响应及系... 半潜式平台在无遮蔽海况下面临波流联合作用引发的系泊失效与运动失稳风险。针对可升降式养殖平台设计方案,通过物理模型试验校核其在维修、漂浮、坐底三类典型工况下的水动力性能。试验采用1∶75缩尺模型,测量平台6自由度运动响应及系泊链张力动态特征。结果显示:维修和漂浮工况下,波流联合作用导致锚泊力达到最大,且不同荷载组合对平台运动的影响很小。波浪周期对锚泊力及纵摇影响显著,但对线位移影响较小。波流联合作用下,锚泊力和线位移随波周期增大而增加,而在纯浪作用下,这一趋势则相反。坐底工况下,平台具有富裕重力,抗滑和抗倾覆性能较强,运动量和锚泊力可忽略。对比了维修状态和漂浮状态的平台动力响应,在海流或波流联合作用下,增加吃水会增大锚泊力并加剧纵摇,同时限制线位移,而在纯浪作用下,增加吃水深度会减小运动响应和锚泊力。研究结果验证了6点系泊方案的稳定性和锚链强度均满足设计要求,为平台建设提供了依据。 展开更多
关键词 半潜式平台 规则波 物理模型试验 浪流联合作用
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甘肃李坝——金山矿集区成矿规律与找矿预测
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作者 李德东 王玉往 +5 位作者 罗建祥 王瑞 丘添伟 张会琼 解洪晶 陈昱 《矿产勘查》 2025年第5期1028-1042,共15页
西秦岭地区金矿床是中国重要金矿资源基地之一,李坝和金山金矿床是中川地区大型金矿床。本文在收集整理并分析以往资料基础上,对甘肃李坝—金山矿集区进行了野外实地调查研究,并对该地区的成矿规律进行了总结。认为该地区的控矿构造主... 西秦岭地区金矿床是中国重要金矿资源基地之一,李坝和金山金矿床是中川地区大型金矿床。本文在收集整理并分析以往资料基础上,对甘肃李坝—金山矿集区进行了野外实地调查研究,并对该地区的成矿规律进行了总结。认为该地区的控矿构造主要因素是中川杂岩体侵入构造作用叠加了区域褶皱+断裂复合构造系统,并从力学角度对中川杂岩体的侵位给2个矿区施加的应力进行分析,结合区域物化探信息构建了李坝—金山矿集区金矿床综合信息找矿预测地质模型,最后在李坝矿区圈定了3处找矿预测潜力区,在金山矿区圈定了2处找矿预测潜力区,以期供矿山企业深边部找矿预测提供参考。 展开更多
关键词 成矿规律 找矿预测 金矿床 李坝—金山 西秦岭
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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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基于社交文本的洪涝信息抽取与时空演变分析 被引量:1
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作者 侯华伟 慎利 +1 位作者 贾嘉楠 徐柱 《地理与地理信息科学》 北大核心 2025年第2期1-9,共9页
以2018年寿光市水灾为例,基于深度学习和规则匹配相结合方法从微博数据中抽取关键灾情信息,通过时间序列分析提取洪涝事件的关键时间节点,利用核密度估计探索灾情的空间分布特征,应用HDBSCAN算法分析核心受灾区域;通过LDA算法对待响应... 以2018年寿光市水灾为例,基于深度学习和规则匹配相结合方法从微博数据中抽取关键灾情信息,通过时间序列分析提取洪涝事件的关键时间节点,利用核密度估计探索灾情的空间分布特征,应用HDBSCAN算法分析核心受灾区域;通过LDA算法对待响应点的文本进行主题分析,提取不同受灾区域面临的问题与需求;基于抽取的水情相关信息和DEM数据,利用HAND模型绘制洪水淹没范围,识别核心受灾区。实验结果表明,该框架的灾情信息抽取总体准确率达83%,高于其他对比方法,可为应急响应提供定向援助与资源配置的决策依据。 展开更多
关键词 社交文本 深度学习 规则匹配 LDA模型 HAND模型
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基于二阶同步提取变换的厚度随机分布薄互层时频响应规律研究
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作者 李雪英 邢博 +2 位作者 文慧俭 王鑫 赵新竹 《地球物理学报》 北大核心 2025年第8期3235-3246,共12页
厚度随机分布薄互层体现地层原始沉积特点,更具一般性,是实际地层分布最广泛的薄互层类型,其时频特征及时变规律的准确刻画对于识别和解释该类薄互层具有重要意义.本文针对厚度随机分布薄互层尚缺少有效的地质建模方法和传统时频分析方... 厚度随机分布薄互层体现地层原始沉积特点,更具一般性,是实际地层分布最广泛的薄互层类型,其时频特征及时变规律的准确刻画对于识别和解释该类薄互层具有重要意义.本文针对厚度随机分布薄互层尚缺少有效的地质建模方法和传统时频分析方法无法定位、划分薄互层内部精细结构的技术难题,利用马尔科夫链建立厚度随机分布薄互层地质模型,采用波动方程正演模拟获取理论合成数据,通过二阶同步提取变换获取时频谱及二阶算子谱.在此基础上,系统总结时域波形、二阶瞬时频谱和二阶算子谱的时频特征及变化规律.研究表明:马尔科夫链是实现厚度随机分布及岩性转换的有效薄互层地质模型方法;二阶同步提取变换方法可高精度表征瞬时频率的变化规律,具有分层次定位及精细划分薄互层内部结构功能:时频谱上的主脊线表征薄互层宏观整体结构及主要能量分布;二阶算子谱中的上、下拱形结构指示次级复合结构突变层位置;高频“X”形结构表征超薄结构突变层产生精微信号.上述成果丰富薄互层地质认识,推进薄互层理论研究工作. 展开更多
关键词 厚度随机分布薄互层 马尔科夫链 二阶同步提取变换 地质建模 时频响应规律
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贵州凯里市硐下地区铅锌矿床地质特征及成矿模式
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作者 张锡贵 房斌 +1 位作者 何善立 代胜 《矿产与地质》 2025年第3期403-411,共9页
贵州凯里市硐下地区铅锌矿床位于区域性湖南(花垣)—铜仁(松桃)—凯里(挂丁)—都匀(三都)北东向深大断裂北西盘凯里东侧挂丁镇附近,湘西—黔东铅锌成矿带中上部,在该区柏松、硐下及龙井街一带寒武系清虚洞组地层上部和顶部发现两个铅锌... 贵州凯里市硐下地区铅锌矿床位于区域性湖南(花垣)—铜仁(松桃)—凯里(挂丁)—都匀(三都)北东向深大断裂北西盘凯里东侧挂丁镇附近,湘西—黔东铅锌成矿带中上部,在该区柏松、硐下及龙井街一带寒武系清虚洞组地层上部和顶部发现两个铅锌含矿层。近些年来,各地勘单位通过不断探索总结和采取有效的勘查手段,在该区累计查明铅+锌金属量大约35万吨,达到中型铅锌矿床规模,实现黔东铅锌成矿带中部的找矿突破。为此,文章根据近年来的找矿勘查成果所取得的认识,与湘西—黔东铅锌成矿带典型矿床进行对比研究,建立凯里地区硐下铅锌矿床的成矿模式,对该区铅锌矿后期找矿工作具有一定的指导意义。 展开更多
关键词 硐下铅锌矿 地质特征 成矿规律 控矿因素 成矿模式
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基于自适应稀疏宽度学习系统的软测量建模 被引量:1
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作者 杜康萍 隋璘 熊伟丽 《系统仿真学报》 北大核心 2025年第6期1449-1461,共13页
针对复杂工业过程具有非线性、变量多特征耦合的特性,导致模型复杂度增加及性能降低等问题,提出一种基于自适应稀疏宽度学习系统的软测量建模方法。在特征横向增强传递的基础上,采用迹LASSO(least absolute shrinkage and selection ope... 针对复杂工业过程具有非线性、变量多特征耦合的特性,导致模型复杂度增加及性能降低等问题,提出一种基于自适应稀疏宽度学习系统的软测量建模方法。在特征横向增强传递的基础上,采用迹LASSO(least absolute shrinkage and selection operator)对网络特征权重进行优化,根据不同变量间的相关性自适应调整惩罚强度,提高模型特征提取能力;在增强节点部分引入Dropout机制,利用LASSO求解输出权重,对模型整体进行稀疏优化,剔除过量节点,减少计算过程中的冗余数据。实验结果表明:该方法能有效简化模型结构,提高其预测性能。 展开更多
关键词 软测量 宽度学习系统 迹LASSO(least absolute shrinkage and selection operator) 正则化 稀疏模型
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电动机故障诊断联邦学习模型研究及技术应用
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作者 周奇才 黄至恺 +2 位作者 钟小勇 卢浩 邱彦杰 《起重运输机械》 2025年第1期78-84,共7页
文中提出了一种基于深度学习以及联邦学习的电动机故障诊断模型。使用Transformer模型对电动机的运行数据进行分析以及故障诊断分类,在此基础上使用FedProx联邦学习算法,在多个客户端上使用不同的数据训练模型,并将训练后的模型上传到... 文中提出了一种基于深度学习以及联邦学习的电动机故障诊断模型。使用Transformer模型对电动机的运行数据进行分析以及故障诊断分类,在此基础上使用FedProx联邦学习算法,在多个客户端上使用不同的数据训练模型,并将训练后的模型上传到中央服务器进行聚合,使用聚合后的模型对设备进行故障诊断。实验结果表明,所提出的模型具有良好的性能,对数据的故障分类准确率满足电动机故障诊断的要求,同时联邦学习的方法有助于模型获得更多的数据特征,使得模型可以更好地进行故障诊断,同时对保护数据隐私也有一定作用。 展开更多
关键词 电动机 故障诊断 Transformer模型 联邦学习 联邦正则算法
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兆瓦级波浪能装置能量俘获特性试验研究
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作者 陈敏 盛松伟 +1 位作者 张亚群 王振鹏 《太阳能学报》 北大核心 2025年第9期248-253,共6页
简要介绍一种大型兆瓦级波浪能装置的设计组成和工作原理,该装置由半潜式浮体、波浪能俘获系统、能量转换系统、锚泊系统组成,采用鹰式吸波浮体和液压能量转换系统将不稳定的波浪能转换为稳定的电能。为研究大型兆瓦级波浪能装置的能量... 简要介绍一种大型兆瓦级波浪能装置的设计组成和工作原理,该装置由半潜式浮体、波浪能俘获系统、能量转换系统、锚泊系统组成,采用鹰式吸波浮体和液压能量转换系统将不稳定的波浪能转换为稳定的电能。为研究大型兆瓦级波浪能装置的能量俘获特性,在拖曳水池开展物理模型试验研究,结果表明装置的能量俘获效率大多在30%~50%之间,最大效率达到56.17%,可实现振荡浮子式波浪能的高效俘获。与侧向吸波相比,鹰式吸波浮体的正面吸波效果更好,其能量俘获效率提高约1.6倍。实海况运行中应将装置同侧5个吸波浮体布置为强浪向,使其正面迎浪。 展开更多
关键词 波浪能装置 兆瓦级 模型 能量俘获效率 规则波 水池试验
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基于Inverted-B+树的海量三维地质块体模型高效索引方法 被引量:1
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作者 陈根深 刘刚 +3 位作者 董洋 范文遥 易强 姜子鑫 《计算机科学》 北大核心 2025年第8期146-153,共8页
三维地质块体模型中大量的零值或空值使得基于B+树的属性索引结构频繁分裂和调整,导致索引维护成本高;同时,B+树的单向链表结构加剧了大规模块体模型中数据顺序遍历和范围查询效率低下的问题。为此,提出了一种基于Inverted-B+树(IBT)的... 三维地质块体模型中大量的零值或空值使得基于B+树的属性索引结构频繁分裂和调整,导致索引维护成本高;同时,B+树的单向链表结构加剧了大规模块体模型中数据顺序遍历和范围查询效率低下的问题。为此,提出了一种基于Inverted-B+树(IBT)的索引方法。该方法通过构建IBT索引结构,在将重复键插入叶子节点时,为每个重复键创建倒排节点,从而有效减少了数据处理中的结构调整。通过在内部节点存储中间索引值来加速查询过程,并在叶子节点和倒排节点之间建立双向链表,实现了从任意叶子节点按顺序访问整个数据集从而进行高效的范围查询。利用三维地质结构模型经过体元剖分、插值和降维处理所得到的6个块体模型进行测试,结果表明:与传统B+树相比,IBT方法在索引构建时间、空间占用和查询性能方面均有显著提升,特别是在处理大规模数据集中,其索引构建效率提升了71%,空间占用减少了83%,查询效率得到了显著提升。 展开更多
关键词 Inverted-B+树 规则块体 三维地质模型 空间数据管理 空间索引
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带目标恢复的无人机长期自适应相关滤波跟踪算法
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作者 马浩然 黄鹤 +3 位作者 林国庆 高涛 王会峰 张科 《南京大学学报(自然科学版)》 北大核心 2025年第1期105-116,共12页
针对无人机跟踪地面运动目标过程中目标场景发生遮挡、光照变化等复杂情况下,相关滤波模型易退化进而导致跟踪精度降低等问题,提出了一种针对无人机对地面目标的稳定实时跟踪算法.首先,利用FHOG,CN和灰度等特征构建外观融合模型,提高对... 针对无人机跟踪地面运动目标过程中目标场景发生遮挡、光照变化等复杂情况下,相关滤波模型易退化进而导致跟踪精度降低等问题,提出了一种针对无人机对地面目标的稳定实时跟踪算法.首先,利用FHOG,CN和灰度等特征构建外观融合模型,提高对复杂场景的适应性;然后,在相关滤波跟踪的基础上,设计自适应局部时空正则化策略,在跟踪器中引入空间正则化来实现像素级的滤波器限制,同时设计时间正则化来优化滤波器的更新;其次,对滤波器进行通道可靠性融合,设计了自适应模型更新策略,防止滤波器退化,提高目标定位的精确度;最后,设计目标恢复模块来提高跟踪器强度,能更好地应对复杂环境.实验结果表明,提出的算法与同类文献算法相比,能更好地适应无人机对地面目标复杂场景的跟踪任务并满足实时性. 展开更多
关键词 目标跟踪 外观融合模型 正则化 通道可靠性 目标恢复
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