查询词典 backward difference operator

In order to obtain actual preferred principle of processing parameter about three-roller backward spinning of tube,nonlinear FEA software ANSYS/LS-DYNA is,carried on 3D dynamic simulation,stress analysis and strain analysis to three-roller backward spinning of tube under different processing parameter.

为了确定更为符合实际的筒形件三旋轮强力反旋工艺参数的选用原则，利用大型非线性有限元软件ANSYS/LS-DYNA对不同工艺参数下筒形件三旋轮强力反旋旋压过程进行了动态模拟和应力应变分析。

In this paper, based on nonlinear FEA software ANSYS/LS-DYNA, 3D dynamic simulation models of eighteen-type tubes for backward spinning was established. This paper not only obtained spinning force of tube backward spinning but also obtained the spinning force curves varying with the different reducer ratio, feeds, fillet radius for spinning roller, forming angle and diameter of spinning roller, and diameter blank inner.

以大型非线性有限元软件ANSYS/LS-DYNA为分析平台，通过对18种几何尺寸和参数不同的筒形件三旋轮强力反旋旋压过程的三维动态模拟，得到了它们的旋压力以及旋压力随不同减薄率，旋轮进给量，旋轮圆角半径，旋轮成形角，旋轮直径和毛坯内径的变化曲线。

The best research tool for the problem of option pricing is backward and forward-backward stochastic differential equation .

简要地介绍了倒向和正倒向随机微分方程在数学金融学的研究中所起的作用。

In this thesis, rat-tails were used as experiment objects, there are 40 slices including transverse and longitudinal, HE-dyed and undyed. Excited by femtosecond laser, the changes of backward SHG and TPEF versus sample preparation, excitation wavelength, excitation power, penetration depth and so on were observed by two-photon laser scanning confocal microscope, effect factors of backward SHG and TPEF and differences of both were discussed and compared, and related comments were also presented.

以鼠尾组织作为实验对象，共40个切片，分为横向和纵向、HE染色和未染色四组，采用飞秒激光器作为激发光，用双光于激光扫描共焦显微镜(two-photon laser scanning confocal microscope， TPLSCM)观察和分析了样品在不同的制备方式、激发波长、激发功率、扫描深度等条件下的背向SHG和TPEF的变化曲线，讨论和比较了生物组织的背向SHG和TPEF的影响因素以及二者之间的异同，并尝试对实验现象做出了一定的解释。

With the compressional stress increasing,the dip-slip motion in listric fault system could successively generate reverse-"fish-fork-shaped" structure,hanging wall interpenetration thrust,footwall shortcut thrust,"backward broken" footwall shortcut thrust imbricated fan,"backward broken interpenetration" thrust,.

随着压应力递增，铲式断层系统中的倾向滑动可渐次形成反转-&鱼叉&状构造、上盘交截冲断层、下盘捷径冲断层、&向后破裂&下盘捷径冲断层叠瓦扇、&向后破裂交截&冲断层、向前破裂后冲断层叠瓦扇、后冲断层与下盘捷径冲断层扇形构造和脊部塌陷&上突&构造等。

One defender of the policy is N. Vasudevan, chief official of the Kafkaesque vision of bureaucratic hell that is the Backward Classes, Most Backward Classes and Minorities Welfare Department in Chennai, where workers languish behind mountains of never-opened files.

这项政策的另一个拥护者是有着卡夫卡式古怪幻想的政务长官 N ·万瓦苏德万，他把金奈地区的落后阶层、最落后阶层以及少数民族福利局看作是官僚主义所造成的地狱，工人们在小山一样永不开封的文件后苟延残喘。

On the other formed, polynomial expressions of intersected point between solution curves of WuestII, reflected shock backward-facing sonic, reflected shock backward-strong/weak separating, Mechanical equilibrium are derived and computed results are marked on the (M0,q1) theoretical solution map of perfect triatomic gas steady Mach reflection.

最后吾人针对WuestII曲线、后向音速曲线、后向强弱曲线、机械平衡曲线，推导它们之间的交点解公式，并将计算的结果标示於平面上之解域图上。

In the research on the backward-wave oscillation suppression the startoscillation current which is derived from Two-wave theory approximately is given up. Four typical un-uniform slow wave structures start-oscillation current equations are derived by backward-wave amplifing gain expressions with the Two-wave theory. Then the start-oscillation current rates I〓/I〓 between ununiform circuit and uniform circuit of the four structures have been got.

在返波抑制问题的研究中，从二波理论出发，抛弃了二波理论中从起振条件出发来得到起振电流近似表达式的方法，而是利用二波理论的基本关系式分别推导出了四种典型实用的非均匀输出线路的返波增益表达式，采用计算返波增益的方法来得到四种非均匀输出线路的起振电流与均匀输出线路起振电流的比值I〓/I〓。

The study suggested:(1) The behavior changing process should increase self-efficacy, let the stage progressive change continue to form the progressive model.(2) The behavior changing initial period should remove the behavioral barrier factors, avoid the backward change to form the backward model.(3) If the behavior maintains the behind stage, should promote perceived benefits, let the stage detrained to form the retain model.

本研究建议行为改变过程应增加自我效能，让阶段前进改变被持续而形成前进模式，改变初期应排除行为障碍因素，避免阶段向后改变而形成后退模式，行为若维持在后面阶段，应提升知觉和说，让阶段被滞留而形成维持模式。

PDA(particle dynamics analyzer system) was used to measure the flow velocity of particles in the XFD-12 flotation cell, the results show that tangential mean velocity in the radial direction changes from positive to negative in the flotation cell, naught point emerge in the medium of the radial direction ,it is where backward fluid emerge ,shear stress of backward fluid induce the particle detachment from bubbles .

汁算数据与实际矿石筛析结果都表明，紊流强度增大，泡沫中粗粒级含量减小。 4。用PDA在XFD-12型8L浮选机中测定的速度值，进行混合区、分离区、泡沫区紊流运动功率谱计算，得紊流脉动频率，混合区小于20Hz，分离区在20-30Hz之间，泡沫区在25-35Hz之间，浮选槽内紊流脉动以低频为主，且紊流脉动动能是混合区大于分离区大于泡沫区。

We have something to do in the new stage.

在这段崭新的时期中，我们有一些要做的。

The difference between tourism decision-making under uncertainty and risky tourism decision-making is indistinctive.

其中不确定性旅游决策和风险旅游决策的界线比较模糊，两者的区分是相对的。