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Uncertainty Analysis of the Residual Strength of Non-Uniformly Loaded Casingsin Deep Wells
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作者 jingpeng wang Wei Zhang +8 位作者 Zhiwei Lin Lin Song Shiyuan Xie Qi Liu Wei wang Tao Yang Kai Xu Meng Li Yuqiang Xu 《Fluid Dynamics & Materials Processing》 EI 2023年第1期105-116,共12页
An uncertainty analysis method is proposed for the assessment of the residual strength of a casing subjected to wear and non-uniform load in a deep well.The influence of casing residual stress,out-of-roundness and non... An uncertainty analysis method is proposed for the assessment of the residual strength of a casing subjected to wear and non-uniform load in a deep well.The influence of casing residual stress,out-of-roundness and non-uniform load is considered.The distribution of multi-source parameters related to the residual anti extrusion strength and residual anti internal pressure strength of the casing after wear are determined using the probability theory.Considering the technical casing of X101 well in Xinjiang Oilfield as an example,it is shown that the randomness of casing wear depth,formation elastic modulus and formation Poisson’s ratio are the main factors that affect the uncertainty of residual strength.The wider the confidence interval is,the greater the uncertainty range is.Compared with the calculations resulting from the proposed uncertainty analysis method,the residual strength obtained by means of traditional single value calculation method is either larger or smaller,which leads to the conclusion that the residual strength should be considered in terms of a range of probabilities rather than a single value. 展开更多
关键词 Casing wear RANDOMNESS UNCERTAINTY non uniform load deep well
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Genome Alignment Spanning Major Poaceae Lineages Reveals Heterogeneous Evolutionary Rates and Alters Inferred Dates for KeyEvolutionary Events 被引量:23
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作者 Xiyin Wa ng jingpeng wang +4 位作者 Dianchuan Jin Hui Guo Tae-Ho Lee Tao Liu Andrew H. Paterson 《Molecular Plant》 SCIE CAS CSCD 2015年第6期885-898,共14页
Multiple comparisons among genomes can clarify their evolution, speciation, and functional innova- tions. To date, the genome sequences of eight grasses representing the most economically important Poaceae (grass) c... Multiple comparisons among genomes can clarify their evolution, speciation, and functional innova- tions. To date, the genome sequences of eight grasses representing the most economically important Poaceae (grass) clades have been published, and their genomic-level comparison is an essential foundation for evolutionary, functional, and translational research. Using a formal and conservative approach, we aligned these genomes. Direct comparison of paralogous gene pairs all duplicated simultaneously reveal striking variation in evolutionary rates among whole genomes, with nucleotide substitution slowest in rice and up to 48% faster in other grasses, adding a new dimension to the value of rice as a grass model. We reconstructed ancestral genome contents for major evolutionary nodes, potentially contributing to understanding the divergence and speciation of grasses. Recent fossil evidence suggests revisions of the estimated dates of key evolutionary events, implying that the pan-grass polyploidization occurred ~96 million years ago and could not be related to the Creta- ceous-Tertiary mass extinction as previously inferred. Adjusted dating to reflect both updated fossil evidence and lineage-specific evolutionary rates suggested that maize subgenome divergence and maize-sorghum divergence were virtually simultaneous, a coincidence that would be explained if poly- ploidization directly contributed to speciation. This work lays a solid foundation for Poaceae transla- tional genomics. 展开更多
关键词 grasses POLYPLOIDY genome alignment evolutionary rates whole-genome duplication
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