特性

Students can learn how to draw single pipe characterization curve and parallel pipe characterization curve through the experiment, and analyze the effect of different valves opening on pipe characterization curve.

通过实验，学生能够掌握单支管路阻力特性曲线的绘制和并联管路阻力特性曲线的绘制方法；能够分析不同阀门开度对管路阻力特性曲线的影响。

Gasification reaction reflected by matter characteristic, real course, gasification equipment was given by the parameter group.

参数群可以很好的反映物料特性、运行特性、气化装置特性对气化反应的影响。

The outcome of the test of the sample's major metal components shows, the material type of 90 per cent of the sample carriers of China's remaining wire-recorded sound archive of traditional and folk music is 18/8 type Chromium-Nickel stainless steel, whose chemical properties have remained intact till today. The parametric test of the sample's major physical property of being magnetic shows, the carriers'physical property of being magnetic has stayed in complete conformity to the conditions of ferromagnetic materials serving as the material for audio signal recording and storage.

样本主要金属成份含量测试结果显示：本课题重点考察的我国钢丝录音遗存音乐音响档案载体品种中90%的材质类型为18/8铬镍不锈钢，它们的化学特性至今仍然保持完整；样本主要物理磁特性参量测试结果显示：这批音响档案载体的物理磁特性完全符合铁磁性材料作为音频信息记录及保存介质材料的基本条件。

To acquire the inherent topology properties and characteristics of the topology graph at AS-level, we introduce basic network model (Scale-free network and Small-world network) and evaluating parameters (such as cluster coefficient, average path length, degree distribution, Pearson correlation coefficient) in this thesis. Through thorough analysis of the topology of the generating topology at AS-level, we can see some apparent properties with the evaluating parameters and the inherent power-law distribution property of the derived topology. Besides, we discuss the perspective of the evolution of the networks topology based on these analyses.

为了研究Internet自治系统级拓扑的内在拓扑特性和规律，利用了复杂网络的基本网络模型(无标度网络和小世界网络)和度量参数(簇系数、平均路径长度、节点度分布、皮尔森系数等)，对生成的自治系统级拓扑进行了大量的分析，从中可以看出度量参数具有一些明显的特性，拓扑中具有一些幂律分布特性，并对网络拓扑的演化发展的趋势进行了探讨。

The character of the target noise is studied systematically, especially the spectrum character of target noise are deeply analyzed. On the basis of it, the power spectrum of two sorts of target noise is estimated with the method of average periodogram using the actual measured data of target noise.

系统地研究了目标声场特性，对目标噪声的产生及其频谱特性进行了深入分析，在此基础上，利用目标噪声实测数据，采用加窗平均周期图法，对两类目标噪声进行了功率谱估计，并对其频谱特性进行了深入分析和研究。

In this chapter, three kinds of target recognition methods are performed, which are:①Target recognition method based on the description of polarization parameter plane. The echo polarization states of target are projected onto the polarization state plane described by the ellipticity ε and the tilt angle τ of the polarization ellipse, the change of parameter following ferquency becomes the chart. According to the changing trait of the chart, the multidimensional polarization feature space of target has been contructed. Furthermore, a series of polarization feature parameters used in designing the structure of target recognition device are extracted, and they are insensible to the posture of target.②Target recognition method based on the description of Poincare polarization sphere. The echo polarization states of target expressed by Stokes vector are projected onto the Poincare polarization sphere. The conception of polarization ferquency stability, which is used in describing the dynamic distribution characteristics of the target echo polarization states on Poincare polarization sphere, has been defined. A group of polarization feature parameters used in designing the structure of target recognition device are extracted, and they are insensible to the posture of target.③Target recognition method based on the description of frequency sensitivity. In accordance with the conception of the polarization state distance defined on Poincare polarization sphere, the frequency sensibility of the physical structure property of target has been investigated, the frequency distribution feature curves in PSD domain are obtained, and targets'features are extracted by means of the curve-fitting method with Least Square Criterion.

这章具体研究了基于三种极化散射特性描述的相应的目标识别方法：①基于极化参数平面描述的目标识别方法，将目标回波极化状态投影到以极化椭圆参数，即椭圆率角ε和倾角τ表征的极化状态平面上，参数随观测频率的变化就形成了图，根据图的变化特点构造了目标的多维极化特征空间，并提取了不敏感目标姿态变化的极化特征参数组来设计目标的识别器结构；②基于Poincare极化球面描述的目标识别方法，采用Stokes矢量表征目标回波的极化状态，并将其投影到描述极化状态的Poincare极化球面上，定义了极化频率稳定度的概念用以刻画目标回波极化状态在Poincare极化球面上的动态分布信息，提取了准方位不变性的目标极化特征，最后设计了目标的识别器结构；③基于频率敏感性描述的目标识别方法，通过在Poincare极化球面上所定义的极化状态距离的概念，研究的是复杂目标物理结构特性对探测信号频率的敏感程度问题，获得了在极化状态距离下的频率分布特性曲线，采用最小二乘估计曲线拟合方法，它既用于极化特征的降维，同时又直接将拟合参数作为目标的分类特征。

The inention relates to a radio wave absorber which can achieve low cost, a small transportation volume, an excellent radio wave absorbing characteristic from a low frequency to a high frequency with a short length, a small or no difference in the characteristic of a polarization plane, and can be easily fabricated and worked.

本发明涉及一种电波吸收件、电波吸收体及其制造方法、以及电波暗室，用于实现下述的电波吸收体，其成本低、输送体积小、长度短、从低频到高频能获得良好的电波吸收特性，没有极化面特性差或该极化面特性差较小、重量轻、结构强度高、制造和施工容易。

Because the above surface breaks the point symmetry of spherical dome, the system may introduce dynamical aberrations depending on Regard of View and Field of View, which is characterized by large tilt and large eccentricity.

但是上述表面破坏了球形整流罩的点对称几何特性，使该系统具有大倾斜、大偏心光学特性，引入依赖于目标视场和瞬时视场的动态像差特性。

The study contains four sections:(1) growth-impact and toxic-symptom of single and compound pollution of Cd and Pb in soil of potherb mustard;(2) effects of different fertilizations on biochemical and psychotic response of potherb mustard;(3) effects of different fertilizations on photosynthetic characteristics of potherb mustard ;(4) effects of different fertilizations on biological effectiveness of heavy metals in soil.

本文主要研究内容包括四个方面：(1)不同水质污水灌溉对雪里蕻生长及其吸收重金属的影响；(2)不同调控措施对雪里蕻生理生化特性的影响；(3)不同调控措施对雪里蕻光和特性的特性的影响；(4)不同调控调控措施对土壤重金属生物有效性的影响。

Measurement of laser proximity fuze target reflective characteristic includes the measurement of target and background characteristic of space and time.

激光近炸引信目标特性测试包括目标与背景激光反射的空间特性和时间特性测试。

I will endeavour to find you some assistance.

我尽力帮你找人帮忙。

At first I only know bruck is the idol of American younglings, afterwards I returned back to Taiwan ,even in Beijing last year ,I saw her poster everywhere, I was so surprised at her charm.

起初我只晓得布鲁克雷德丝是美国少男少女崇拜的偶像，后来回台湾，甚至去年在北京，居然也四处看见她的海报，才惊讶她的魅力之大。