临界点

They've lost sight of the point at which the influence of social forces ends and the influence of the self-initiating individual begins.

他们已经失去了判断在社会影响力和个人主动影响力之间的&临界点&。

In Chapter 2, an existence theorem is obtained for periodic solutions of non-autonomous second order systems with even-typed potentials. We also investigate solutions of linear bounded positive self-conjugation operators equations in Hilbert Space by variation methods.

第二章主要利用临界点理论中的归药方法、极小作用原理研究具偶型位势的二阶非自治系统周期边值问题，得到了周期解的存在；利用变分方法证明了Hilbert空间中有界线性正自共轭算子方程解的存在性。

Chapter 4 is devoted to the existence and multiplicity of homoclinic for self-adjoint nonlinear second order difference equations by using "Mountain Pass " theorem and "Symmetry Mountain Pass "theorem in critical point theory.

第四章应用临界点理论中的山路引理与对称山路引理研究了一类自共轭非线性二阶差分方程的同宿轨的存在性与多重性。

At the same time, from two critical points-levying scale and selling prices, taking Xian as an example, this paper provides some references for the government on land levying scale based on the use of mathematical simulation and cost of land.

在此基础上，运用数学模拟和成本法从征地规模和土地出让价格的决策临界点两个方面，以西安市为例作了实证研究，为政府在确定合理征地规模方面的决策提供了参考。

In the process of building and using the mass concrete structures, because of the effect of out-side condition and themselves, some faults will form in the structure, these faults will effect the bearing capability and endurance Using nondestructive testing method to test the concrete"s quality and diagnose its healthy, which has the significant sense in assessing the safety stability and research of the administering diseasesThis dissertation mostly researched the testing methods in the mass concrete structure, discussed the principles, methods, features, sphere of application of the ultrasonic testing in the mass concrete structure with faults, used dynamic FEM to simulate the testing process, discussed when the concrete structure with cracks is under the effect of the pulse, how the elastic waves propagate and what are their changing feature, Researched the principles of the first-arriving waves" phase when the cracks" depths are not same, obtained the relation between the inversion point and the cracks" depth, which has the direction sense in the application of projects,The second part of this dissertation is CT , which used the ultrasonic wave running through the tested-substance to get arriving-time of the ultrasonic wave, then inverse the image This dissertation drawed one CT program which can well present the different little cells ultrasonic wave velocity profiles of the substance, thereby to diagnose the quality of the part of the tested-substance, CT has the better using foreground..

在混凝土结构的施工及使用过程中，由于受其自身及外界各种因素的影响，常常会产生一些缺陷，对结构物的承载能力和耐久性造成严重影响，采用无损检测技术进行质量检测和健康诊断，这对混凝土结构开展安全、稳定性评估以及病害隐患治理研究具有重要意义。本论文主要针对大体积混凝土结构缺陷的检测方法展开研究工作，重点讨论了超声波法检测混凝土结构裂缝的基本原理和方法及其特点、适用范围，运用动力有限元数值模拟其检测过程，探讨了有裂缝缺陷的混凝土结构在脉冲荷载作用下弹性波的传播及其变化特征，研究了不同裂缝深度下首波相位变化规律，得出了反转临界点与裂缝深度之间的关系，这对实际工程应用具有指导意义。声波CT是一种新的无损检测技术，它是利用声波穿透被检测体获取声波接收时间，来进行计算机反演成像的技术。本文利用直射线法编制了层析成像程序，能较好地呈现被检测物体各微小单元的声波速度分布图像，从而对检测体的质量状况作出诊断评估，具有较好的应用发展前景。

When a wing stalls the wing loses most of its downforce and drag.A single element wing will then stall, as the flow breaks up under the wing

但是当超过临界点，尾翼气流完全分离从而导致失速的时候，空阻会大幅减小，下压力也会戏剧性的降低。

The function of active view analysis on ARC/INFO is surveying land-form features of a selected fight line. The fight line is generated by critical points that the user selects.

ARC／INFO动态视点分析是动态观察分析地形图上某条路线的地形特点，该路线是以用户所选取的临界点为基础形成的。

We use eigenvalue analysis todetermine the instability of the target pattern under control condition,and find a four-mixing-wave mode,which has never been mentionedin previous works,serving as the eigenfunctions of the CGLE system.

从中我们首次发现了受控系统的不稳定模可以写成四波混合的形式，这种不稳定模的形式成功地描述了受控CGLE在临界点的失稳状态。

By Ricceri's three critical points theorem, the existence of solutions for a class of quasilinear elliptic systems with variational structure was proved and the location of the solutions was also determined.

通过运用Ricceri的一个三临界点定理，讨论了一类具变分结构的拟线性椭圆方程组，获得了多解的存在性，并且给出了解的位置。

Its are to attract everybody adequately to use as a result, after the breakthrough is bit more critical, information stores the volume will rise, accordingly, this kind of effective design can drive his to use growth ceaselessly .

其结果是充分吸引大家使用，在突破临界点后，信息存储量将增长，因此，这种有效的设计会不断推动其使用增长。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。