查询词典 variation method

Based on the return map and the principle of closed vectors, a new method is proposed to extract unstable periodic orbits embedded in chaotic attractors. As examples, the UPOs embedded in chaotic attractors of Logistic, Hénon and Lorenz are extracted respectively by this method. And our results of Skewed Hénon map also be compared with Nusse's. These results suggest that this method is valid for unstable periodic orbits from period one to period infinite of arbitrary dimension chaotic system. The dynamic considerations of spiking and UPO coding for individual neuron and neural system under external periodic and chaotic exciting stimulus also be studied in this dissertation. A lot of spiking phenomena, such as synchronization, period, and chaos appear alternatively with the changing of the stimulus frequency. For the small stimulus frequency the neuron could completely convey the periodic signal in synchronous anti-phase into interspike intervals sequences. For the slow time–scale chaotic input, the output two ISI sequences are reciprocally related to input signals, and their oscillation wave shape in time course can be derived from that of the input signals variation, furthermore, the similar input sequence and order of UPOs, distribution of LES and value of KYD remain in attractors reconstructed from ISI sequences.

发现周期信号在单个神经元传递过程中，随着激励频率的改变，神经元输出的峰峰间期interspike interval时间序列呈现出周期、混沌和准周期的交错变化，特别当外加激励信号频率较低时，周期信号可以通过神经元ISI序列以反相同步的周期运动形式传递下去；同时无论是周期还是混沌激励信号，在神经系统中的传递均与其自身强度和神经元之间的耦合强度的大小密切相关；快变时间尺度的混沌激励信号在耦合的神经系统传递过程中，会造成大量基本信息的丢失；而慢变时间尺度的混沌激励信号在神经系统传递中，它的非线性特征信息，如混沌吸引子、不稳定周期轨道、Lyapunov指数谱和分形维数，会通过系统输出的ISI序列部分地重现出来，如与输入慢变时间尺度的混沌激励信号相比，神经系统输出的ISI序列具有：相似几何形状的混沌吸引子、相近的Lyapunov指数谱和分形维数、局部结构相同的不稳定周期轨道的排列方式。

In my theory of absolute velocity of matter, I will show that the variation within all these experimental results, not only IS NOT due to experimental error, but that the measure of the variation itself is of paramount importance to our understanding of physical laws, and indeed of the whole universe.

在我的物质绝对速度理论中，我会展示所有这些实验中的变化量，不仅不是实验的误差，而且这些数值变化所具有的重要性，除了体现在我们对物理定律的理解中，还体现在我们对整个宇宙的理解中。

Adamson reviews scholarship in sociolinguistics and second language acquisition, comparing theories of variation in first- and second-language speech, with special attention to the psychological underpinnings of variation theory.

在这本书中高清亚当森评语奖学金语言学和第二语言习得，比较，第一和第二语言的讲话变化的理论，并特别注意心理变异的理论基础。

The Frechet derivative of the cost function is determined via the solution of an adjoint partial differential equation, and the boundary shape is then modified in a direction of descent. This process is repeated until an optimum solution is approached. The advantage is that the cost function variation is independent of the flow field variation, with the result that the gradient of cost function with respect to arbitrary number of design variables can be determined without the need for additional flow-field evaluations. So each design cycle requires the numerical solution of both the flow and the adjoint equations leading to a computational cost roughly equal to the cost of two flow solutions.

虽然他们的研究成果大多数都可以在公开性文献上看到，但是其中一些具体的细节问题的处理方法却没有透露，比如：伴随方程如何离散求解才能减小最终梯度计算中的误差，使得设计过程有效地进行；伴随方程与流动方程的边界条件是不同的，如何合理地处理伴随方程的边界条件，才能推动设计过程朝着设计目标而发展；在减阻问题中目标函数如何定义，求解梯度的具体数学公式如何推导，如何通过数值方法来实现它们等。

The main results were as follows: 1.After being radiated with 60 Co-γ, seven types of mutated plants were obtained through morphologic observation on the aftergrowth of the regeneration plantlets. The mutation characters included the purple leaf vein and petiole, the spotted leaf, the strumae leaf, the acerose leaf, the tender stem, the leaf shape variation, and the leaf color variation.

通过60 Co-γ射线诱变处理后的再生植株试管苗阶段的形态学观察，共获包括紫色叶柄、斑叶、瘤状叶片、细长叶片、茎杆细小、叶型变异、叶色变异的7种不同类型的变异植株。

The oscillation of the base level results in their relative variation of accommodation space and sedimentary alimentation. The variation rates of them have also changed, then lead to the difference of facies sequence, the degree of stratigraphic preservation and stacking pattern at the same territory in different ages, or the difference of phase area at different territories at the same age.

由於基准面的升降变化引起了可容纳空间与沉积物供给量的相对变化，相对应的可容纳空间变化率和沉积物供给率同时也发生变化，因而导致了在不同时期同一地区的地层在相序、保存程度和叠加样式上的差异，以及在同一时期内不同地区在相域上的差别。

Population variation and differences in serum leptin independent of adiposity: a comparison of Ache Amerindian men of Paraguay and lean American male distance runners - Background: Serum leptin variation is commonly associated with fat percentage, body mass index, and activity.

人口变化和差异瘦素独立肥胖：比较酸痛精益美洲印第安人和巴拉圭男子中长跑男-背景：瘦素变化都与脂肪百分比，身体质量指数、活性。

Based on these data,AOT and Angstrom parameters were retrieved.Through analyzing the variation of AOT and Angstrom parameters,the reason which cause the variation was discussed.

利用这些数据，反演了气溶胶光学厚度和相应的Angstrom参数，分析了光学厚度和Angstrom参数的日变化和逐日变化，并讨论了这些变化的原因。

Based on the reanalysis of JEDAC datasets and the assimilation of SODA, the authors studied the variation of the heat status in the West Pacific Warm pool and discussed the ocean temperature variety in the heat content at different depths, the inherent relations between ocean temperatures at surface and subsurface, the eastward propagation of anomalous ocean temperature and the thermocline variation, and the influence of equatorial undercurrent on the eastward propagation.

中文摘要：应用 JEDAC 海温和SODA 再分析资料，分析研究了西太平洋暖池的热状况变化特征，探讨了WPWP 的热含量变化与不同深度海温变化，特别是与表层和次表层海温场之间的内在联系，分析研究了WPWP 异常海温东传过程中与温跃层变化之间的关系，最后讨论了赤道潜流在异常海温东传过程的作用。

Based on the former studies, this paper promotes an innovation about this topic using new satellite altimetry data and hydrographic data along with numerical experiments: Firstly, the temporal variation of the deformation of Kuroshio accompanied by the periodically shed anticyclonic eddies from the Kuroshio bend is discovered; Secondly, the major mechanism of the anticyclonic eddy separating from the Kuroshio bend, which is the frontal instability, is brought forward and then proved; Thirdly, the factors with important impact on the periodical variation of the Kuroshio bend and the eddy shedding, which are the strength of the Kuroshio transport and the circulation in the winter SCS, are determined.

本文在前人工作的基础上，利用了最新的卫星遥感资料和海洋调查资料，通过数值模式的数值实验，得到了以下前人没有得到的创新成果：发现在吕宋海峡处黑潮的形变随时间变化，并伴有反气旋涡周期性地从黑潮主体中脱落；提出并证明了吕宋海峡黑潮锋附近的锋面不稳定是反气旋涡从黑潮弯曲中脱落的主要机制；确定了对黑潮弯曲周期性变化以及反气旋涡脱落有重要影响的物理因素是黑潮流量的大小及冬季南海局地环流。

Don not attempt to do something which you can not to do.

不要企图做那些办不到的事情。

The expression of CTGF and TNF-αweredetected by immunochemistry and the number of Clara Cells was calculated.

光镜下观察肺组织的病理变化，采用免疫组化染色观察肺组织中结缔组织生长因子和肿瘤坏死因子-α的表达和Clara细胞的数量。