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51.
The paper investigates the performance of various time stepping schemes for coupled displacement and pore pressure analysis.
A number of alternative forms of the automatic time stepping method proposed by Sloan and Abbo (1999a) are also presented.
These alternative schemes use different updates for the displacements and pore pressures and also adopt different starting
conditions for the iterations. The automatic schemes are compared with an implicit θ-method, as well as an explicit method,
through analysis of a variety of problems involving undrained loading, drained loading, and consolidation for Mohr-Coulomb
and critical state models. As expected, the numerical results confirm that the explicit scheme is neither accurate nor robust.
Although the implicit θ-method is accurate and fast, it fails to give a solution in a number of cases where the time step
is large. The automatic schemes are shown to be accurate, fast and generally robust. Two of the automatic schemes proposed
never fail to furnish a solution for the cases considered. In addition, all the automatic schemes are able to constrain the
time-stepping (temporal integration) error in the displacements and pore pressures to lie near a prescribed tolerance, provided
the iteration error tolerance is properly chosen. For complex soil models, it is important that the latter is set sufficiently
small in order for the schemes to be able to constrain the time-stepping error to lie within a prescribed tolerance.
Dedicated to the memory of Prof. Mike Crisfield, for his cheerfulness and cooperation as a colleague and friend over many
years. 相似文献
52.
严陆光 《电气电子教学学报》2003,25(5):1-4
结合自身的学习、工作经历,与研究生畅谈如何学会“做人、做事、做学问”。 相似文献
53.
54.
55.
Composite element model for discontinuous rock masses 总被引:2,自引:0,他引:2
56.
介绍了一个基于Windows操作系统的数据采集软件,该软件用于使用重心法确定的位置信息的位置灵敏探测器,具有方便的人机交互界面,使用专用驱动程序采集数据。 相似文献
57.
A type of CO2 sensor based on oxygen concentration cell was designed as following: Cell I: Pt | Au, O2,CO2|Na2CO3(Au)|NKBA(Au)|YSZ|O2, CO2|Pt or Cell Ⅱ: Pt|Au, O2, CO2|K2CO3(Au)|NKBA(Au)|YSZ|O2, CO2|Pt.(Na,K-β/β″-Al2O3 is named by NKBA). The sensor signal is consistent with the Nernstian slope within the region ofphase equilibrium for Na, K-β/β"-Al2O3 material. The relationship between CO2 sensor voltage response and phaseequilibrium of solid electrolyte Na, K-β/β-Al2O3 is discussed in this paper. 相似文献
58.
The molecular mechanisms underlying the clustering and localization of K+ channels in specific microdomains on the neuronal surface are largely unknown. The Shaker subclass of voltage-gated K+ channel alpha-subunits interact through their cytoplasmic C-terminus with a family of membrane-associated putative guanylate kinases, including PSD-95 and SAP97. We show here that heterologous coexpression of either sap97 or PSD-95 with various Shaker-type subunits results in the coclustering of these proteins with the K+ channels. Mutation of the C-terminal sequence (-ETDV) of the Shaker subunit Kv1.4 abolishes its binding to, and prevents its clustering with, SAP97 and PSD-95. Whereas PSD-95 induces plaque-like clusters of K+ channels at the cell surface; however, SAP97 coexpression results in the formation of large round intracellular aggregates into which both SAP97 and the K+ channel proteins are colocalized. The efficiency of surface clustering by PSD-95 varies with different Shaker subunits: striking Kv1.4 clustering occurs in > 60% of cotransfected cells, whereas Kv1.1 and Kv1.2 form convincing clusters with PSD-95 only in approximately 10% of cells. 相似文献
59.
对《基于GIS技术的安徽省重大农业气象灾害测评系统》的总体设计方法作了概要介绍。该系统的建立主要是采用GIS技术,综合气候分析、遥感监测、地理环境影响评判等方法,提高对安徽省干旱、洪涝、低温冻害等重大农业气象灾害实时监测、趋势预测,以及对农业生产影响的分析评价结果的准确性。 相似文献
60.