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51.
从地质建模的流程入手,总结了建模过程中质量控制方法,主要从基础数据准备和质量控制,构造模型质量控制,相模型的质量控制,属性模型的质量控制,模型验证五个方面加以质量控制。在多个项目中的应用表明能够显著地提高地质模型的质量。 相似文献
52.
In this paper a recursive state-space model identification method is proposed for non-uniformly sampled systems in industrial applications. Two cases for measuring all states and only output(s) of such... 相似文献
53.
Sumit K. Kiran Vaughn M. Nace Maximilian A. Silvestri Keith A. Monk Jeremy Moloney Loreen Schmidt Edgar J. Acosta 《Journal of surfactants and detergents》2014,17(6):1193-1201
The partitioning of corrosion inhibitor (CI) products is a measure of their potential to protect oilfield pipelines. In this paper the hydrophilic–lipophilic deviation (HLD) model is first used to quantify their partitioning in terms of the characteristic curvature (C c,act) of a series of anionic (alkoxylated phosphate esters) and cationic (alkoxylated amines, aromatic amines, imidazoline acetates and quaternary amines) actives. This parameter is expressed over a range of pHs within which pipeline corrosion occurs. The HLD model is next used to predict the partitioning of each active from water into toluene at increased salinities. Linear mixing rules are lastly used to predict the characteristic curvature of Product A (C c,mix) as a function of the C c,act of a subset of actives. 相似文献
54.
Jorge C. Ramirez Perla J. Hernández-Belmares Jorge Herrera-Ordonez 《Journal of surfactants and detergents》2022,25(4):455-465
Association between poly(vinyl alcohol-co-vinyl acetate) copolymer (PVA) and sodium dodecyl sulfate (SDS) was studied experimentally and theoretically. It was found that, for the ethyl acetate-aqueous phase interface in which PVA was previously adsorbed, the interfacial tension (γ) increases abruptly to a maximum and then exhibits a relatively mild decay with the addition of SDS to the aqueous phase. The theoretical results indicate that vinyl acetate (VAc) segments determine γ. However, for relatively low concentrations of SDS (CSDS), this latter plays a major role because through its association with the VAc segments it modulates the extent to which PVA is adsorbed at the interface, indirectly determining the value of γ. As CSDS approaches to the CMC value for SDS, its influence on γ decreases because SDS tends to self-assembly rather than associates with VAc. These model predictions are consistent with experimental findings reported in the literature. 相似文献
55.
It is well known that the deformation and stress-resistant characteristics of fine-grained soils, especially soft clays, are significantly influenced by the soil softness. It is therefore very important to employ a model which can accurately simulate the effects of this phenomenon. A constitutive model must be able to create a balance among stress paths, the number of parameters, the process of parameter determination, and finally, the simplicity of the computational calculations.The current study investigates the performance of a two-yield surface (cone and cap yield surface) model for soft soils. The efficiency of the cap yield surface has been studied as well. The model has been calibrated by employing the data derived from previous researches for Bangkok clay. The incorporated data have been obtained from the results of CD triaxial, CU triaxial, and oedometer tests. The proposed method for the model calibration can accurately predict the triaxial test results and oedometer test stress path simultaneously. This method for predicting the soil behavior is based on the main soil characteristics taken from common soil mechanics tests. It can be widely employed for engineering practices, especially when complicated soil behavior is encountered. 相似文献
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姬连俊 《机电产品开发与创新》2008,21(2):22-23
飞机结构损伤的有效记录与控制.是飞机保持持续适航的关键。本文从基于飞机二维结构特征的观点提出了飞机损伤监控系统的新思路。该系统涵盖了损伤与修理的计算机特征描述。并采用直观的二维损伤索引定位图,方便飞机放行人员对放行飞机损伤类别的整体了解,达到时时监控。 相似文献
59.
论文调查了国内外基于数据挖掘技术的人口数据预测模型。根据预测目的不同对这些模型进行了分类比较,在此基础上综合各模型的优缺点,对今后的研究工作做了进一步展望。 相似文献
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