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Geochemical characteristics and genetic model of dolomite reservoirs in the eastern margin of the Pre-Caspian Basin 被引量:13
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作者 Wang Shuqin Zhao Lun +2 位作者 Cheng Xubin Fan Zifei He Ling 《Petroleum Science》 SCIE CAS CSCD 2012年第2期161-169,共9页
The widespread Carboniferous KT-I dolomite in the eastern margin of the Pre-Caspian Basin is an important hydrocarbon reservoir. The dolomite lithology is dominated by crystalline dolomite. The δ18O values range from... The widespread Carboniferous KT-I dolomite in the eastern margin of the Pre-Caspian Basin is an important hydrocarbon reservoir. The dolomite lithology is dominated by crystalline dolomite. The δ18O values range from -6.71‰ to 2.45‰, and average 0.063‰, obviously larger than -2.5‰, indicating low-temperature dolomite of evaporation origin. Stable strontium isotope ratios (87Sr/86Sr) range from 0.70829 to 0.70875 and average 0.708365, very consistent with 87Sr/86Sr ratios in Carboniferous seawater. Chemical analysis of Ca and Mg elements shows that the dolomite has 9.1 mole% excess Ca or even higher before stabilization. The degree of order of dolomite is medium–slightly poor, varying in a range of 0.336-0.504 and averaging 0.417. It suggests that the dolomite formed under near-surface conditions. There are two models for the origin of the Carboniferous KT-I dolomite reservoir. These are 1) the evaporation concentration – weathering crust model and 2) the shoal facies – seepage reflux model. The former is mainly developed in restricted platforms – evaporate platforms of restricted marine deposition environments with a representation of dolomite associated with gypsum and mudstone. The latter mainly formed in platform edge shoals and intra-platform shoals and is controlled by dolomitization due to high salinity sea water influx from adjacent restricted sea or evaporate platform. 展开更多
关键词 ISOTOPE DOLOMITE CARBONIFEROUS genetic model eastern margin of Pre-Caspian Basin
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Patterns and Dynamics of Rifting on Passive Continental Margin from Shelf to Slope of the Northern South China Sea:Evidence from 3D Analogue Modeling 被引量:14
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作者 孙珍 周蒂 +4 位作者 吴世敏 钟志洪 Myra Keep 姜建群 樊浩 《Journal of China University of Geosciences》 SCIE CSCD 2009年第1期136-146,共11页
Affected by thermal perturbation due to mantle uprising, the rheological structure of the lithosphere could be modified, which could lead to different rifting patterns from shelf to slope in a passive continental marg... Affected by thermal perturbation due to mantle uprising, the rheological structure of the lithosphere could be modified, which could lead to different rifting patterns from shelf to slope in a passive continental margin. From the observed deformation style on the northern South China Sea and analogue modeling experiments, we find that the rift zone located on the shelf is characterized by half grabens or simple grabens controlled mainly by long faults with large vertical offset, supposed to be formed with normal lithosphere extension. On the slope, where the lithosphere is very hot due to mantle upweUing and heating, composite grabens composed of symmetric grabens developed. The boundary and inner faults are all short with small vertical offset. Between the zones with very hot and normal lithosphere, composite half grabens composed of half grabens or asymmetric grabens formed, whose boundary faults are long with large vertical offset, while the inner faults are relatively short. Along with the thickness decrease of the brittle upper crust due to high temperature, the deformation becomes more sensitive to the shape of a pre-existing weakness zone and shows orientation variation along strike. When there was a bend in the pre-existing weakness zone, and the basal plate was pulled by a clockwise rotating stress, the strongest deformation always occurs along the middle segment and at the transition area from the middle to the eastern segments, which contributes to a hotter lithosphere in the middle segment, where the Baiyun (白云) sag formed. 展开更多
关键词 passive continental margin rifting pattern 3D analogue modeling South China Sea.
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Zero Truncated Bivariate Poisson Model: Marginal-Conditional Modeling Approach with an Application to Traffic Accident Data
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作者 Rafiqul I. Chowdhury M. Ataharul Islam 《Applied Mathematics》 2016年第14期1589-1598,共11页
A new covariate dependent zero-truncated bivariate Poisson model is proposed in this paper employing generalized linear model. A marginal-conditional approach is used to show the bivariate model. The proposed model wi... A new covariate dependent zero-truncated bivariate Poisson model is proposed in this paper employing generalized linear model. A marginal-conditional approach is used to show the bivariate model. The proposed model with estimation procedure and tests for goodness-of-fit and under (or over) dispersion are shown and applied to road safety data. Two correlated outcome variables considered in this study are number of cars involved in an accident and number of casualties for given number of cars. 展开更多
关键词 Bivariate Poisson Conditional model Generalized Linear model marginal model Road Safety Data Zero-Truncated
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Causal inference with marginal structural modeling for longitudinal data in laparoscopic surgery: A technical note
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作者 Zhongheng Zhang Peng Jin +7 位作者 Menglin Feng Jie Yang Jiajie Huang Lin Chen Ping Xu Jian Sun Caibao Hu Yucai Hong 《Laparoscopic, Endoscopic and Robotic Surgery》 2022年第4期146-152,共7页
Causal inference prevails in the field of laparoscopic surgery.Once the causality between an intervention and outcome is established,the intervention can be applied to a target population to improve clinical outcomes.... Causal inference prevails in the field of laparoscopic surgery.Once the causality between an intervention and outcome is established,the intervention can be applied to a target population to improve clinical outcomes.In many clinical scenarios,interventions are applied longitudinally in response to patients’conditions.Such longitudinal data comprise static variables,such as age,gender,and comorbidities;and dynamic variables,such as the treatment regime,laboratory variables,and vital signs.Some dynamic variables can act as both the confounder and mediator for the effect of an intervention on the outcome;in such cases,simple adjustment with a conventional regression model will bias the effect sizes.To address this,numerous statistical methods are being developed for causal inference;these include,but are not limited to,the structural marginal Cox regression model,dynamic treatment regime,and Cox regression model with time-varying covariates.This technical note provides a gentle introduction to such models and illustrates their use with an example in the field of laparoscopic surgery. 展开更多
关键词 Causal inference Laparoscopic surgery Machine learning marginal structural modeling
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Marginalized cubature Kalman filtering algorithm based on linear/nonlinear mixed-Gaussian model
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作者 Hu Yumei Hu Zhentao Jin Yong 《High Technology Letters》 EI CAS 2018年第4期362-368,共7页
Aiming at improving the estimation accuracy and real-time of nonlinear system with linear Gaussian sub-structure,a novel marginalized cubature Kalman filter is proposed in Bayesian estimation framework. Firstly,the ma... Aiming at improving the estimation accuracy and real-time of nonlinear system with linear Gaussian sub-structure,a novel marginalized cubature Kalman filter is proposed in Bayesian estimation framework. Firstly,the marginalized technique is adopted to model the target system dynamics with nonlinear state and linear state separately,and the two parts are estimated by cubature Kalman filter and standard Kalman filter respectively. Therefore,the linear part avoids the generation and propagation process of cubature points. Accordingly,the computational complexity is reduced.Meanwhile,the accuracy of state estimation is improved by taking the difference of nonlinear state estimation as the measurement of linear state. Furthermore,the computational complexity of marginalized cubature Kalman filter is discussed by calculating the number of floating-point operation. Finally,simulation experiments and analysis show that the proposed algorithm can improve the performance of filtering precision and real-time effectively in target tracking system. 展开更多
关键词 state estimation marginalized modeling mixed-Gaussian model CUBATURE KALMAN FILTER
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Numerical modeling of the development of southeastern Red Sea continental margin
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作者 Sunil Kumar Dwivedi Daigoro Hayashi 《Earthquake Science》 CSCD 2009年第3期239-249,共11页
The Red Sea continental margin (RSCM) corresponds to a wide hinge zone between Red Sea and Arabian plate. This margin has been studied through geological and geophysical observations primarily in regard to the evolu... The Red Sea continental margin (RSCM) corresponds to a wide hinge zone between Red Sea and Arabian plate. This margin has been studied through geological and geophysical observations primarily in regard to the evolution of Red Sea rift. This margin is characterized by occurrence of thin sediments, significant onshore uplift, tectonic subsidence of the offshore sedimentary basin, active faulting and seismicity. Studies indicate that sedimentary sequences of the margin are deformed by faults and folds resulting from at least two phases of extension and a phase of uplift. During the two phases of extension due to regional plate stress the sequence was cut by set of extensional faults. While during the phase of uplift the sequence was deformed by folding and faulting. The present paper aims to clear the structural development of RSCM during these tectonic episodes, taken as particular tectonic event, by two-dimensional finite element modeling on plane strain condition. Elastic theology is assumed for the oceanic, continental and transitional crust along with syntectonic deposits. Stress field, shear stress and fault distribution suggests that mantle plume weakened the crust following rifting due to regional stress and developed the margin. These results are well consistent with those from present seismicity, active faulting and neotectonic studies. 展开更多
关键词 Red Sea rift continental margin numerical modeling SEISMICITY NEOTECTONICS
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Stratigraphic Architecture and Computer Modelling of Carbonate Platform Margin,Late Ordovician Lianglitage Formation,Central Tarim Basin 被引量:2
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作者 李浩 林畅松 +3 位作者 张燕梅 张荣茜 芮志峰 黄理力 《Journal of Earth Science》 SCIE CAS CSCD 2012年第4期627-638,共12页
According to the different geometries and reflected characteristics in the seismic sections, the carbonate platform margin of the northern slope can be summarized as three basic depositional architectures in the Late ... According to the different geometries and reflected characteristics in the seismic sections, the carbonate platform margin of the northern slope can be summarized as three basic depositional architectures in the Late Ordovician Lianglitage (良里塔格) Formation of the Tazhong (塔中) uplift. The type one mainly located in the west of the carbonate platform margin, and it showed obvious imbricate progradation from the interior to the margin of the platform. The type two was in the middle of the carbonate platform margin, which showed retrogradational stacking pattern in the same transgres- sive systems tract period, and the slope strata of the platform margin showed progradational sequence in the highstand systems tract period. The type three located in the east of the carbonate platform margin, and it showed the parallel aggradational architecture. The crossing well section along the northern slope of the Tazhong carbonate platform showed that the depositional thickness became thinner from the east to the west. The thickest belt located in the east of the platform margin, and became thinner rapidly towards the basin and the platform interior. These indicated that the paleogeomorphology ofthe Tazhong uplift was probably high in the west and low in the east during the period of the Late Ordovician Lianglitage Formation. According to the interpretation of seismic profiles and the computer modelling result, the depositional architectures of sequence O31-2 showed aggradation, retrogradation and progradation from the east to the west of the carbonate platform margin during the transgression period. This meant that the accommodation became smaller gradually from the east to the west along the northern carbonate platform margin of the Tazhong uplift.The difference of the accommodation was probably caused by the difference of tectonic subsidence. Also, computer-aided modelling can be used to deeply understand the importance of various control parameters on the carbonate platform depositional architectures and processes. 展开更多
关键词 carbonate platform margin depositional architecture tectonic subsidence accommo-dation modelling.
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Modeling Water Quality Impacts of Growing Corn, Switchgrass, and <i>Miscanthus</i>on Marginal Soils 被引量:1
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作者 Mark A. Thomas Laurent M. Ahiablame +1 位作者 Bernard A. Engel Indrajeet Chaubey 《Journal of Water Resource and Protection》 2014年第14期1352-1368,共17页
The goal of the study was to model water quality impacts of growing perennial grasses on marginal soils. The GLEAMS-NAPRA and RUSLE models were used to simulate long-term surface runoff, percolation, erosion, total ph... The goal of the study was to model water quality impacts of growing perennial grasses on marginal soils. The GLEAMS-NAPRA and RUSLE models were used to simulate long-term surface runoff, percolation, erosion, total phosphorus (TP), and nitrate (NO3-N) losses associated with the production of corn-based bioenergy systems (i.e. conventional tillage corn and corn grain plus stover removal), switchgrass and Miscanthus on three marginal quality soils and one good quality soil in Indiana. Simulations showed that switchgrass and Miscanthus had no effect on annual runoff, but decreased percolation by at least 17%. Results also suggested a potential for reduction in erosion for Miscanthus across the soil types examined when compared to corn-based bioenergy production. The production of switchgrass and Miscanthus did not have significant effects on the simulated TP and NO3-N losses in runoff compared to corn production systems. Nitrates leached from fertilized Miscanthus production were approximately 90% lower than NO3-N leached from the production of fertilized switchgrass and corn systems. Additional studies are needed to better understand the hydrology, erosion and nutrient responses of Miscanthus and switchgrass production to meet bioenergy demands. 展开更多
关键词 Water Quality modelING Perennial Grass Runoff Biofuels marginAL Lands GLEAMS-NAPRA
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Marginal Conceptual Predictive Statistic for Mixed Model Selection
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作者 Cheng Wenren Junfeng Shang Juming Pan 《Open Journal of Statistics》 2016年第2期239-253,共15页
We focus on the development of model selection criteria in linear mixed models. In particular, we propose the model selection criteria following the Mallows’ Conceptual Predictive Statistic (Cp) [1] [2] in linear mix... We focus on the development of model selection criteria in linear mixed models. In particular, we propose the model selection criteria following the Mallows’ Conceptual Predictive Statistic (Cp) [1] [2] in linear mixed models. When correlation exists between the observations in data, the normal Gauss discrepancy in univariate case is not appropriate to measure the distance between the true model and a candidate model. Instead, we define a marginal Gauss discrepancy which takes the correlation into account in the mixed models. The model selection criterion, marginal Cp, called MCp, serves as an asymptotically unbiased estimator of the expected marginal Gauss discrepancy. An improvement of MCp, called IMCp, is then derived and proved to be a more accurate estimator of the expected marginal Gauss discrepancy than MCp. The performance of the proposed criteria is investigated in a simulation study. The simulation results show that in small samples, the proposed criteria outperform the Akaike Information Criteria (AIC) [3] [4] and Bayesian Information Criterion (BIC) [5] in selecting the correct model;in large samples, their performance is competitive. Further, the proposed criteria perform significantly better for highly correlated response data than for weakly correlated data. 展开更多
关键词 Mixed model Selection marginal Cp Improved marginal Cp marginal Gauss Discrepancy Linear Mixed model
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Gravity Modeling for the Rifted Crust at the Arabian Shield Margin – Further Insight into Red Sea Spreading
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作者 Saad Mogren Manoj Mukhopadhyay 《Open Journal of Geology》 2013年第2期28-33,共6页
A large variation in elevation and gravity anomaly prevails from the Red Sea coast to the interior of the Arabian Shield (AS) across the Asir Igneous Province (AIP);The Asir Mountain (AM) is developed on AIP. Here the... A large variation in elevation and gravity anomaly prevails from the Red Sea coast to the interior of the Arabian Shield (AS) across the Asir Igneous Province (AIP);The Asir Mountain (AM) is developed on AIP. Here the elevation varies from 45 - 2700 m, corresponding changes in F.A. are from –30 to + 220 mgal and B.A. from +22 to –175 mgal. Regression relationships between elevation and gravity anomalies demonstrate significant changes in trend at about 400 m threshold of elevation across the pediment west of AM, at about 45 km inland of the shoreline, flanking the Hizaz-Asir Escarpment (HAE). Gravity anomaly variation along a traverse taken across HAE and AIP is interpreted here in terms of anomalous masses in crust as well as due to deeper crustal configuration. 2D gravity interpretation is, in part, constrained by surface geology, available geologic cross-sections for crust, interpretations from the IRIS Deep-Seismic Refraction Line, and to a lesser extent by the available gross results from shear-wave splitting and receiver function analysis. The gravity model provides probable solutions for the first time on geometric configuration and geophysical identification: a) for the seaward margin of the mid-Tertiary Mafic Crust (TMC) below sediment cover of the Asir pediment that coincides with the 400 m threshold elevation. This signifies an anomalous uplift at the rifting phase. Moho below TMC extends from 10 - 22 km depth across HAE and west margin of AIP, b). Thinned continental crust below the Asir margin whose upper layer coincides with a seismic reflector is at about 22 km depth, c). Rift-margin characteristic detachment fault associated with basaltic flows on top surface of TMC at its inner margin, d). Two geologically mapped low-angle normal faults dipping to the east developed between the basic rocks intruding the AIP and e). felsic pluton farther east within AS. Large scale igneous activity followed by intense deformation affecting AIP clearly owes their origin to the rifting architecture of the AS at the Red Sea extensional margin. 展开更多
关键词 Shield-margin MAFIC CRUST Asir IGNEOUS Province Seismic MOHO 2D Gravity CRUSTAL model Red Sea Ex-tensional margin
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Margins模型及其在流行病学交互作用分析中的应用
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作者 殷国桓 董子钰 +2 位作者 阿木吉力特 叶泓 许群 《环境卫生学杂志》 2025年第9期786-791,共6页
边际效应(margins)模型作为一种基于回归的边际效应估计方法,近年来在环境健康研究中展现出独特的交互作用识别能力,尤其适用于揭示复杂暴露组合下多元交互结构的方向与强度。本文系统梳理了margins模型在环境流行病学领域的理论基础与... 边际效应(margins)模型作为一种基于回归的边际效应估计方法,近年来在环境健康研究中展现出独特的交互作用识别能力,尤其适用于揭示复杂暴露组合下多元交互结构的方向与强度。本文系统梳理了margins模型在环境流行病学领域的理论基础与实际应用,结合多种重金属混合暴露研究案例,探讨其在不同健康结局中的适用性、建模策略及解释优势。与传统交互项回归相比,margins模型可在控制协变量基础上定量刻画三元及以上交互结构,并提供明确的方向性判断;相较贝叶斯核机器回归、加权分位数和回归等非参数模型,其在高阶交互构建与亚群体分层解释方面具备良好扩展性。尽管该方法在非线性建模、高维变量选择与可视化表达方面仍存在一定局限,但其与贝叶斯方法、惩罚回归与机器学习技术的融合正在拓展其理论边界与应用前景。本文认为,margins模型有望在未来多暴露-多结局的研究框架中成为识别关键交互结构、支持因果推断与风险分层的核心工具。 展开更多
关键词 边际效应模型 多元交互作用 环境流行病学 混合暴露 流行病学
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An accurate analytical I-V model for sub-90-nm MOSFETs and its application to read static noise margin modeling
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作者 Behrouz AFZAL Behzad EBRAHIMI +1 位作者 Ali AFZALI-KUSHA Massoud PEDRAM 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2012年第1期58-70,共13页
We propose an accurate model to describe the I-V characteristics of a sub-90-nm metal-oxide-semiconductor field-effect transistor(MOSFET) in the linear and saturation regions for fast analytical calculation of the cur... We propose an accurate model to describe the I-V characteristics of a sub-90-nm metal-oxide-semiconductor field-effect transistor(MOSFET) in the linear and saturation regions for fast analytical calculation of the current.The model is based on the BSIM3v3 model.Instead of using constant threshold voltage and early voltage,as is assumed in the BSIM3v3 model,we define these voltages as functions of the gate-source voltage.The accuracy of the model is verified by comparison with HSPICE for the 90-,65-,45-,and 32-nm CMOS technologies.The model shows better accuracy than the nth-power and BSIM3v3 models.Then,we use the proposed I-V model to calculate the read static noise margin(SNM) of nano-scale conventional 6T static random-access memory(SRAM) cells with high accuracy.We calculate the read SNM by approximating the inverter transfer voltage characteristic of the cell in the regions where vertices of the maximum square of the butterfly curves are placed.The results for the SNM are also in excellent agreement with those of the HSPICE simulation for 90-,65-,45-,and 32-nm technologies.Verification in the presence of process variations and negative bias temperature instability(NBTI) shows that the model can accurately predict the minimum supply voltage required for a target yield. 展开更多
关键词 modelING NANO-SCALE Process variation Read static noise margin(SNM) SRAM
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基于改进TimeGAN数据增强的用户窃电识别研究
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作者 吴佐平 王宏岩 +1 位作者 张千福 谢青 《电气传动》 2026年第1期75-81,共7页
用户窃电是电网电能非技术损失的主要原因,对电力系统造成了巨大的经济损失和资源浪费。相较于大量用户正常用电样本,窃电用户属于少数类样本,而传统窃电分类方法在样本稀疏或失衡情况下表现不佳。由此,提出一种基于改进时间序列生成对... 用户窃电是电网电能非技术损失的主要原因,对电力系统造成了巨大的经济损失和资源浪费。相较于大量用户正常用电样本,窃电用户属于少数类样本,而传统窃电分类方法在样本稀疏或失衡情况下表现不佳。由此,提出一种基于改进时间序列生成对抗网络(TimeGAN)数据增强的用户窃电分类方法,使用TimeGAN对原始小样本窃电数据进行增强,生成与原始数据分布相似的增广样本,考虑到增广样本存在噪声或不可信等问题,利用马氏距离评估增广样本的质量,完成不可信样本剔除。通过卷积神经网络(CNN)对数据增强后的用电负荷数据进行特征提取,采用长短时记忆网络(LSTM)提取特征量的时序相关性并完成特征分类,进一步,利用麻雀搜索算法(SSA)对CNN-LSTM网络进行参数优化,提高模型检测精度。实验结果表明,所提方法可有效解决用户窃电行为识别中样本不平衡的二分类问题。 展开更多
关键词 TimeGAN模型 马氏距离 麻雀搜索算法(SSA) 窃电识别
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基于AGSCOA-Stacking特征加权的船用钢板焊接余量预测
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作者 谢久超 苌道方 《计算机工程》 北大核心 2026年第1期414-426,共13页
为了提升钢板焊接的精度,提高船体质量和建造效率,提出一种自适应黄金正弦螯虾优化算法(AGSCOA)-Stacking特征加权代理模型的方法,用于解决船用钢板焊接余量预测问题。首先,基于Stacking集成学习策略,根据所提出的PC指标,从多种机器学... 为了提升钢板焊接的精度,提高船体质量和建造效率,提出一种自适应黄金正弦螯虾优化算法(AGSCOA)-Stacking特征加权代理模型的方法,用于解决船用钢板焊接余量预测问题。首先,基于Stacking集成学习策略,根据所提出的PC指标,从多种机器学习模型中筛选出兼具高预测精度和差异性的基学习器。其次,提出一种特征加权方法,针对所筛选基学习器的预测性能进行自适应特征加权,从而提高模型的泛化能力。最后,对传统螯虾优化算法进行多方面改进,引入正交折射反向学习机制来改进种群初始化,确保初始种群质量;提出自适应Lévy飞行策略来优化探索阶段,避免陷入局部最优;引入黄金正弦算法改进开发阶段,平衡全局搜索与局部开发能力。利用改进后的AGSCOA对代理模型进行多参数优化,从而提升模型预测精度。实验结果表明,AGSCOA在优化性能和收敛速度上表现出色,所提出的代理模型相比线性加权集成学习代理模型、AGSCOA-SVR、AGSCOA-ET和AGSCOA-RF具有更高的预测精度,均方根误差(RMSE)分别降低了14.29%、35.78%、17.48%和22.31%。 展开更多
关键词 焊接余量预测 Stacking集成学习 代理模型 螯虾优化算法 折射反向学习机制 黄金正弦算法
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西藏冈底斯南缘新生代隆升剥露历史及地质意义
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作者 韩飞 李建江 +10 位作者 秦宇龙 赵海波 杨学俊 叶春林 李峥 贾小川 黄柏鑫 张彤 熊昌利 黄永高 罗改 《地学前缘》 北大核心 2026年第2期440-450,共11页
宏伟高大的青藏高原隆升形式和时限是地学界长期关注的课题。为了揭示其隆升机制及剥蚀过程,对西藏冈底斯南缘奴玛地区花岗岩进行低温热年代学研究,共获得7组磷灰石裂变径迹实验数据,裂变径迹年龄为30~22 Ma,皆晚于白垩世和始新世花岗... 宏伟高大的青藏高原隆升形式和时限是地学界长期关注的课题。为了揭示其隆升机制及剥蚀过程,对西藏冈底斯南缘奴玛地区花岗岩进行低温热年代学研究,共获得7组磷灰石裂变径迹实验数据,裂变径迹年龄为30~22 Ma,皆晚于白垩世和始新世花岗岩体的形成年龄,基本记录了晚渐新世—早中新世阶段冈底斯南缘隆升冷却历史。磷灰石平均径迹长度为(13.2±1.8)~(14.3±1.8)μm,均小于原始径迹长度(16±1)μm,表明磷灰石经历过较强的退火作用。磷灰石热史模拟显示,冈底斯南缘奴玛地区经历了一个持续隆升冷却过程,整体隆升幅度为6603~7443 m,隆升速率为0.27~0.31 mm/a。隆升冷却过程大致可分为3个阶段:40~20 Ma、20~10 Ma和10 Ma至今。3个阶段分别对应印度-欧亚大陆俯冲碰撞、冈底斯构造带大型逆冲推覆构造运动和南北向伸展运动3次重大地质事件。此次研究丰富了青藏高原渐新世隆升机制及模型,同时对早期形成的矿床能否得以保存具有重要的指示意义。 展开更多
关键词 冈底斯南缘 隆升 磷灰石 裂变径迹 热史模拟
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A Simple Shear Model for the Asymmetry in the Paleoproterozoic Fold Belt in Liaodong Peninsula 被引量:3
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作者 Cui Yingchun, Liu Junlai, Ma Lijie and Guan Huimei (Dept. Earth Sci., Jilin University, Changchun 130061 P.R. China) 《Global Geology》 2001年第1期26-33,共8页
Several aspects of the Liaodong Paleoproterozioc fold belt, including its components, tectonic, metamorphic and magmatic characteristics are discussed in the paper, with emphasis on the asymmetry of the fold belt and ... Several aspects of the Liaodong Paleoproterozioc fold belt, including its components, tectonic, metamorphic and magmatic characteristics are discussed in the paper, with emphasis on the asymmetry of the fold belt and differences between the northern lineal-fold belt and the southern dome-fold belt. It is suggested that the fold belt is one magmatic passive margin, instead of a rift zone or the classical passive continental margin. The formation and evolution of the fold belt is dis- cussed with a simple shear model, which may best explain the co-existence of contemporaneous tectonic facies with different characteristics, the volcanic and plutonic activities, sedimentary formations and their geological attributes etc. 展开更多
关键词 Liaodong differentiation MAGMATIC passive CONTINENTAL margin SIMPLE shear model
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Impacts of prior parameter distributions on Bayesian evaluation of groundwater model complexity 被引量:1
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作者 Saeideh Samani Ming Ye +4 位作者 Fan Zhang Yong-zhen Pei Guo-ping Tang Ahmed Elshall Asghar A.Moghaddam 《Water Science and Engineering》 EI CAS CSCD 2018年第2期89-100,共12页
This study used the marginal likelihood and Bayesian posterior model probability for evaluation of model complexity in order to avoid using over-complex models for numerical simulations. It focused on investigation of... This study used the marginal likelihood and Bayesian posterior model probability for evaluation of model complexity in order to avoid using over-complex models for numerical simulations. It focused on investigation of the impacts of prior parameter distributions(involved in calculating the marginal likelihood) on the evaluation of model complexity. We argue that prior parameter distributions should define the parameter space in which numerical simulations are made. New perspectives on the prior parameter distribution and posterior model probability were demonstrated in an example of groundwater solute transport modeling with four models, each simulating four column experiments. The models had different levels of complexity in terms of their model structures and numbers of calibrated parameters. The posterior model probability was evaluated for four cases with different prior parameter distributions. While the distributions substantially impacted model ranking, the model ranking in each case was reasonable for the specific circumstances in which numerical simulations were made. For evaluation of model complexity, it is thus necessary to determine the parameter spaces for modeling, which can be done by conducting numerical simulation and usineg engineering judgment based on understanding of the system being studied. 展开更多
关键词 marginAL LIKELIHOOD POSTERIOR model probability ADVECTION-DISPERSION equation Mobile-immobile model GROUNDWATER model
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Cenozoic tectono-sedimentary characteristics and extension model of the Northwest Sub-basin,South China Sea 被引量:8
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作者 Weiwei Ding Mingbi Li +2 位作者 Lihong Zhao Aiguo Ruan Zhenli Wu 《Geoscience Frontiers》 SCIE CAS 2011年第4期509-517,共9页
Based on the interpretations of three seismic profiles and one wide-angle seismic profile across the Northwest Sub-basin,South China Sea.stratigraphic sequences,deformation characteristics and an extension model for t... Based on the interpretations of three seismic profiles and one wide-angle seismic profile across the Northwest Sub-basin,South China Sea.stratigraphic sequences,deformation characteristics and an extension model for this sub-basin have been worked out.Three tectonic-stratigraphic units are determined.Detailed analyses of extension show that the event occurred mainly during the Paleogene and resulted in the formation of half-grabens or grabens distributed symmetrically around the spreading center.Sediments are characterized by chaotic and discontinuous reflectors,indicating clastic sediments. Farther to the southwest,the sub-basin features mainly continental rifting instead of sea-floor spreading. The rifting would have been controlled by the shape of the massif and developed just along the northern edge of the Zhongsha-Xisha Block,rather than joined the Xisha Trough.After 25 Ma.a southward ridge jump triggered the opening of the Southwest Sub-basin.The NW-directed stress caused by the sea-floor spreading of the Northwest Sub-basin may have prevented the continuous opening of the sub-basin.After that the Northwest Sub-basin experienced thermal cooling and exhibited broad subsidence.The deep crustal structure shown by the velocity model from a wide-angle seismic profile is also symmetrical around the spreading center,which indicates that the Northwest Sub-basin might have opened in a pure shear model. 展开更多
关键词 Continental rifting CENOZOIC Tectono-sedimentary characteristics Extension model Northwest Sub-basin marginal sea
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Chronology,Geochemistry and Tectonic Settings of the Hadamiao Granodiorite on the Northern Margin of the North China Platform 被引量:3
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作者 HAO Baiwu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第6期1500-1513,共14页
The Hadamiao granodiorite,located on the northern margin of the North China platform and acting as the country rock of gold deposits in the Hadamiao region,was formed in the same age and similar tectonic settings with... The Hadamiao granodiorite,located on the northern margin of the North China platform and acting as the country rock of gold deposits in the Hadamiao region,was formed in the same age and similar tectonic settings with the Hadamiao gold deposit and the large-scale Bilihe gold deposit in the same area.By using the LA-ICP-MS method,the U-Pb age obtained is 267±1.3 Ma,which represents the crystallized age of the granodiorite,and that of the xenolithic zircon is 442.8±5 Ma. Base on the main elements,it exhibits the features of calc-alkaline to high-potassium calc-alkaline series,low silicon,and quasi-aluminous I-type granites,and with high magnesium(Mg~#=0.45-0.57) and high sodium contents(Na_2O/K_2O=0.98-2.29).The SREE values(81.6-110.15 ppm) are relatively low,the fractionations between LREE and HREE are obvious,showing a right-inclined dispersion in the REE distribution diagram.Compared with the primitive mantle,the rock is relatively rich in LREE(La and Ce),LILE(K,Sr,and Th),and intensively depleted in HFSE(Ti,P,Nb and Ta).The ratios of Sr/Y and(La/Yb)_N and the contents of Rb,Nb and Y are relatively low,the Sr values are high (436.35-567.26 ppm),and the Yb contents of most samples are low(1.25-1.8),which indicate the features of typical continental margin arc and adakitic rocks.According to the values ofε_(Nd)(t)(-2.4 to +0.2) and I_(Sr)(0.7028-0.7083),and variations of the La/Sm ratios,the Hadamiao granodiorite was formed from mixing of the thickened molten lower crust and the mantle wedge substances.The rock was related to the southward subduction and accretion of the Paleo-Asia Ocean in the Late Paleozoic, being Late Paleozoic magma of the continental margin arc formed on the basement of the Early Paleozoic accretion complexes,and showing a trend of turning into adakitic rocks,which indicates their great metallogenic(Au) potential. 展开更多
关键词 Hadamiao granodiorite zircon LA-ICP-MS U-Pb dating GEOCHEMISTRY tectonic setting genetic model northern margin of the North China platform
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Asymmetry Index on Marginal Homogeneity for Square Contingency Tables with Ordered Categories
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作者 Kouji Tahata Kanau Kawasaki Sadao Tomizawa 《Open Journal of Statistics》 2012年第2期198-203,共6页
For square contingency tables with ordered categories, the present paper considers two kinds of weak marginal homogeneity and gives measures to represent the degree of departure from weak marginal homogeneity. The pro... For square contingency tables with ordered categories, the present paper considers two kinds of weak marginal homogeneity and gives measures to represent the degree of departure from weak marginal homogeneity. The proposed measures lie between –1 to 1. When the marginal cumulative logistic model or the extended marginal homogeneity model holds, the proposed measures represent the degree of departure from marginal homogeneity. Using these measures, three kinds of unaided distance vision data are analyzed. 展开更多
关键词 marginAL HOMOGENEITY marginAL CUMULATIVE Logistic model Measure SQUARE CONTINGENCY Table
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