Results 41 to 50 of about 1,437,872 (201)
Shiyou jixie, 2014 自动液压动力卡瓦是井口机械自动化的重要一环。介绍了液压动力卡瓦的产品分类及特点，概述了液压动力卡瓦技术发展现状，尤其对当前NOV、B+V以及Weatherford公司的典型液压动力卡瓦的结构参数和性能特点进行了重点分析研究。最后指出了液压动力卡瓦的发展趋势：①向承载多样化，夹持多元化方向发展；②向高安全性、高可靠性方向发展；③向控制操作智能化、集成化方向发展。
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Dizhen xuebao, 2020 本文基于Biot动力固结理论和弹性动力学理论，考虑海床（土壤）的两相性、黏弹性人工边界及流（水）-固耦合作用，建立了隧道-土-流体相互作用的力学模型，讨论了P波作用下有无水的情况以及水深、水域隧道埋深、海床土性质和地震波入射角等因素对隧道及其周围海床应力的影响。结果表明：隧道周围海床土的孔隙水压力和隧道内应力随着水深的增加而增加；地震波特性和海床土特性对隧道的内应力和海床土的孔隙水压力均有较大的影响；海床土的渗透性和隧道埋深对隧道的内应力影响较小，而对隧道周围海床土的孔隙水压力影响较大 ...
Zhiyong Ouyang +4 more
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How Do I Measure up? Social Influence and L2 Motivation in the Algorithmic Age
International Journal of Applied Linguistics, EarlyView.ABSTRACT Comparative thinking is a fundamental human drive and a hallmark of contemporary life. For social action, such as the learning and use of additional languages, a target for appraisal (an L2 attribute) is evaluated in relation to a comparison standard (an appraiser's standpoint).
Alastair Henry, Meng Liu
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Synthesizing Empirical Research on Learner Metacognition in Second Language Writing
International Journal of Applied Linguistics, EarlyView.ABSTRACT Despite considerable research interest in learner metacognition in second language (L2) writing, there is not yet a review that synthesizes the existing empirical findings and discusses their implications. To fill the void, this systematic review synthesized 39 empirical studies on learner metacognition in L2 writing and examined their salient
Chen Li, Icy Lee, Zhicheng Mao
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Shuitu Baochi Xuebao, 1995 从水力学与泥沙运动力学观点，对初生态侵蚀性坡面薄层水流的基本动力特性，如流产；充态、临界水深、阻力系数等几个基本问题，作了半理论性探讨。
沙际德 蒋允静
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International Journal of Applied Linguistics, EarlyView.ABSTRACT With the increasing number of Chinese international students in Australian universities, intercultural competence has become a critical factor influencing their interactions with Australian tutors in university classroom settings. Existing research often examines students’ intercultural competence from a single‐method or single‐perspective ...
Jiangyu Han, Linda Tsung
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, 2017 基于Reynolds average Navier-Stockes（RANS）的三维Navier-Stokes流场控制方程耦合结构静力学方程时域分析方法,研究了带有发动机的民用飞机其动力效应对全机气动性能的影响。首先采用数值方法对发动机进排气边界条件进行了模拟,分析了带动力的涡扇发动机模型的流场,并将计算结果与实验进行比较,验证边界条件处理的准确性;以此为基础,考虑结构弹性变形,采用计算流体动力学/计算结构动力学（CFD/CSD）耦合的方法,分别对通气和带动力的翼吊发动机全机的气动性能进行了研究 ...
黄程德 +3 more
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Gaoya dianqi, 2004 对与真空断路器相配的弹簧操动机构而言,其输出力特性和开关负载特性的合理匹配取决于凸轮机构的合理设计。按全程输出力大于阻力的原则,采用分段多项式方法确定了凸轮轮廓线。凸轮机构的理论计算与试验结果比较吻合,表明该方法能够有效地实现凸轮机构的优化设计,在满足操动机构运动特性的前提下,可降低弹簧刚度和输出力。
闫静, 马志瀛, 金黎
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