查询词典 higher derivative

The permissiveness of American society is the soil to produce the multiplicity of American higher education. The superiority of American higher education is embodied in it's multiplicity and the American higher education is based on its cultural background. The multiplicity vitalizes American higher education, from which we can learn how to develop the multiplicity of higher education with Chinese characteristics under market economy.

美国高等教育多元化的产生有其社会文化背景，美国的宽容文化是美国高等教育文化产生的土壤，它决定了美国高等教育的多元化，而美国高等教育多元化的优越性也从中得以体现，多元化使美国高等教育生机勃勃，这值得我们深思，在市场经济体制下，我国高等教育应该怎样走&有中国特色&的多元化道路。

In the paper,the fresh,withered,rocked and fermented leaf fixed by microwave and steam were studied.The results showed that the content of pol yphenols of microwave samples was higher than those of steam samples;and the con tent of amino acids in steam samples was higher than those of microwave samples .There was a slight higher content of soluble sugars in microwave samples compa red with steam samples. The content of chlorophyll of microwave samples was hig her than steaming samples,and there was a small difference of caffeine content b etween microwave and steam samples.There was a little higher content of theafla vins in microwave samples than steam samples.The content of thearubigins in steam samples was higher than microwave samples,and there was no differe nt theabrown between microwave and steam samples.

摘 要：对鲜叶、萎凋叶、做青叶和发酵叶进行了微波和蒸青固样研究，结果表明：微波样的多酚类化合物保留量均高于蒸青样，氨基酸保留量则相反，可溶性糖的保留量微波样稍高于蒸青样，叶绿素的保留量微波样亦稍高于蒸青样，咖啡碱的保留量微波样与蒸青样间差异较小，发酵叶茶黄素的保留量微波样稍高于蒸青样，发酵叶茶红素的保留量微波样高于蒸青样，发酵叶茶褐的保留量二者间无差异。

Therefore, the EL spectra of (Znq_2)_4 is wider than that of Znq_2. 4._2 was synthesized. The analysis of molecular spatial structure and the characterization of material performance of_2 and Liq showed that two Liq molecules and two Naq molecules were connected by Na-O-Na bond bridges to form_2. Compared with Liq,_2 exhibits stronger rigidity in planar molecular structure, larger steric hindrance and intermolecular distance, and much smaller molecular polarity, thus resulting in much longer fluorescence lifetime, much higher fluorescence quantum efficiency, wider energy bandgap and better film formability. When used as light-emitting layer in OLED,_2 shows lower formation probability of excited dimmer and exciplex formation than Liq, thus emits bluer light with higher current efficiency than Liq. When_2 ultrathin film is used as electron injection layer in OLED, it exhibits higher current density, higher luminance, lower turn-on voltage and higher current efficiency than Liq ultrathin film for the existence of sodium ions in_2 ultrathin film. 5. The summarization the relationship between molecular spatial structure and material performance of Alq_3,(Znq_2) and Liq, lead the conclusion that the molecular spatial structure of Mq_n affects its material performance in such aspects as the rigidity of planar molecular structure, intermolecular interaction, molecule stacking mode and intermolecular distance.

制备了_2，通过对_2和Liq的分子空间结构与性能进行分析与讨论，发现_2是通过两个Na-O-Na键桥将两个Liq和两个Naq连接构成的，其分子平面结构的刚性程度强于Liq，空间位阻大于Liq，分子之间的距离大于Liq，分子极性远远小于Liq；_2的荧光寿命长于Liq，荧光量子效率高于Liq，成膜性优于Liq；_2的禁带宽度比Liq大，光致发光光谱中_2的最大发射峰较Liq发生蓝移；当_2在OLED中作为发光层时，激发二聚体与激基复合物的生成几率远远小于Liq，发的光比Liq更蓝，电流效率大于Liq；_2超薄膜中有Na离子的存在，与Liq超薄膜相比，当其在OLED中作为电子注入层时，具有更大的电流密度，更高的发光强度，更低的阈值电压和更高的电流效率 5、对上述Alq_3、Znq_2和Liq的分子空间结构与材料性能之间的关系进行了归纳总结，认为Mq_n的分子空间结构主要在分子平面结构的刚性程度，相邻分子之间的相互作用，分子堆叠的方式和分子之间的距离这四个方面影响其性能。

Pole-placement and Inner model tuning methods are discussed finally;(2) For the linear derivative action, several different tracker-differentiators are presented to improve the quality of the derivative signals;(3) A neural network tuning method is given for the nonlinear PID controller which includes the above tracker-differentiator;(4) For the linear integral action, a nonlinear pre-phase integrator is studied in order to decrease the phase delay problem; Simulation results show that the nonlinear PID controller including the pre-phase integrator posseses better performance in both fast and stable property, and strong ability of anti-disturbance;(5) A simple optimal criteria is introduced to optimize the parameters of the nonlinear PID controller based on the pre-phase integrator.

仿真研究表明，由此形成的非线性复合积分PID控制系统，具有快速而平稳的过渡过程和超强的干扰抑制能力；(5)采用物理意义简单明确的目标函数的优化设计方法，对上述非线性PID控制器进行参数整定，达到了满意控制典型工业过程的目的。通过对直线电机伺服系统的仿真研究，表明该种非线性控制器具有同时跟踪多个目标的优越性能。

Its primary coverage includes: Function and limit, derivative and differential, theorem of mean and derivative application, indefinite integral, definite integral and application, space analytic geometry and vector algebra, function of many variables differential method and application, multiple integral and curvilinear integral, infinite series, differential equation and so on.

其主要内容有：函数与极限，导数与微分，中值定理与导数应用，不定积分，定积分及其应用，空间解析几何与矢量代数，多元函数的微分法及其应用，重积分与曲线积分，无穷级数，微分方程等。

IV. The total synthesis of dehydrodiconiferyl alcohol and its dihydro-derivative The benzofuran skeleton was constructed by chemically oxidative couplingstarting from vanillin, then selective reduction with LiAI〓/〓 andhydrogenation in the presence of Pd-C followed reduction with LiAl〓respectively, to give dehydrodiconideryl alcohol and its dihydro-derivative, usefulin treating and preventing digestive system disorders, esp.

四、Dehydrodiconiferyl alcohol及其二氢衍生物的全合成以香草醛为起始原料，用化学氧化法一步建立氢化苯骈呋喃骨架，LiAlH〓／〓选择性还原以及催化加氢还原接着〓还原，分别合成了对预防和治疗消化系统疾病尤其是胃溃疡有显著效果的Dehydrodiconiferylalcohol及其二氢衍生物。

One UV absorber is a benzotriazole derivative, and the other UV absorber is a benzophenone derivative.

一种紫外吸收化合物是苯并三唑衍生物，另一种紫外吸收剂为二苯酮衍生物。

The chain rule is just how to take the derivative of chained functions — meaning, function x calls function g, and you want the derivative of xg

链式法则仅仅是如何对链式函数求导的意思，函数 x 引用函数 g ，你要求导 xg

Firstly, this paper investigated roundly the basic theory of the ambient vibration method, analyzed systematically the main methods of ambient vibration identification, and discussed their advantages and disadvantages. Then we established the finite element model of structural dynamics and test model and analyzed their mutual relation, improved MUSIC method and correlation function method in the harmonic identification, and gave the subspace method and correlation function method based on continuous model, which is multi-harmonic retrieve technique. And then, this paper also puts forward least-squares method to estimate directly structural physical and modal parameters; this approach replaced the derivative operator in the continuous time model with an equivalent approximation, and estimated the physical parameters of structures by the least-squares method. And then, we discussed the approximation methods of derivative and their convergence. Finally, this paper researched the modal parameters of a frame structure by the simulation and test. The results demonstrated that subspace method, correlation function method and the least-squares method are effective and stable respectively.

全面地研究环境振动识别方法的基本理论，系统地分析环境振动识别方法的主要方法，讨论它们的优点和不足；建立结(来源：6666AB44C论文网www.abclunwen.com)构动力学的有限元模型和试验模型，分析有限元模型与试验模型之间的相互关系；改进谐波识别中的MUSIC识别方法和相关函数识别方法，给出大型结构模态识别的连续型的子空间分解识别方法和相关函数识别方法，这个方法是多元谐波识别方法；提出直接识别结构的物理参数和模态参数的最小二乘方法，这个方法利用导数的近似值代替导数值，并运用最小二乘方法识别结构的物理参数，讨论导数近似值的选择方法，分析算法的收敛性；通过仿真计算和模型实验，研究高层框架结构的模态参数识别，验证子空间分解识别方法、相关函数识别方法和最小二乘识别方法的有效性，算法的稳定性；从理论和试验两个方面分析和研究噪声对识别精度的影响，影响识别精度的因素，以及部分模态成分的模态参数不能够被识别的原因。

The definitions of generalized directional derivative and generalized gradient of Lipschitz functions defined on Riemannian manifold are presented. Some properties of the directional derivative and gradient are proved by using tangent and cotangent mapping. The minimization necessary condition of nonsmooth Lipschitz functions is given. Moreover, Fritz John necessary optimality condition in mathematical programming is provided on Riemannian manifold.

在黎曼流形上给出了Lipschitz函数的广义方向导数和广义梯度的概念，利用黎曼流形局部上与欧氏空间开集微分同胚的性质以及切映射和余切映射导出了广义梯度的性质和运算法则，证明了定义在黎曼流形上的函数取得极小值的必要条件是广义梯度包含零元素，并利用这些性质给出了黎曼流形上数学规划问题的Fritz John型最优性条件。

You can do some assertiveness training.

你可以进行一些自信训练。

We were well on the path to making a rear-wheel-drive global platform," says Mays."

我们正致力于建立一个后轮驱动的平台，"Mays这样说道。"