查询词典 characteristic set

The characteristic approximation is used to handle the convection part along the direc-tion of fluid namely characteristic direction to ensure the high stability of the method in approximating the sharp fronts and reduce the numerical diffusion; The mixed finite element spatial approximation is employed to deal with diffusion part and approximate the scalar unknown and the adjoint vector function optimally and simultaneously; In order to preserve the integral conservation of the method, we introduce the modified characteristic method.

该方法对方程的对流部分沿流体流动的方向即特征方向离散以保证格式在流动的锋线前沿逼近的高稳定性，消除数值弥散现象；对方程的扩散部分采用最低次混合有限元方法离散、同时以高精度逼近未知函数及未知函数的梯度；为保证方法的整体守恒性，在格式中引入修正项。

Aiming at the signal processing problems that exist in online fault diagnosis for train running gear, based on discussing the principle of characteristic spectrum analysis, a method of full period and uniform angle sampling is applied, which transfers the vibration signal from time domain into angular domain. The angular domain signal is transferred into corresponding characteristic spectrum using FFT. Through spectrum estimation and analysis, fault characteristic spectrum values of running gear components are acquired to distinguish their faults.

在讨论特征分析方法原理的基础上，针对机车走行部故障在线监测过程中存在的信号分析与处理问题，运用整周期等角度采样方法将时域振动信号转换为角域信号，采用FFT变换将角域信号变换为对应的特征频谱，通过谱估计、谱图分析得到机车走行部各零部件的故障特征谱值，再根据该特征谱值识别机车走行部各零部件的故障。

A theoretical model is built to investigate the simulation of the infrared characteristic of the metal structure with the PCM false target.Structure parameters of the PCM false target that suit for the simulation are investigated numerically.According to the results,further request on the improvement of the thermal conductivity of PCM is presented.An experimental platform is built and the numerical model is validated experimentally.Three key thermal characteristic components of the false tank(barbette,wheel and front armor plate) are manufactured and tested,and good results are obtained.A method for the thermal conductivity enhancing of PCM by using aluminum fins is studied,the influence of the structure parameters of PCM plates to the simulation effects are investigated numerically,and the reasonable configuration parameters of the PCM plates used to simulate the steel plates of different thickness are obtained.In the study of the application of heat convection method in IR false target,a passive infrared simulation system is designed to simulate the infrared characteristic of metal constructions.The system is made up of pipe-plate,pump,receiver,and working fluid.

在相变材料应用于红外示假的研究中，通过数值模拟，研究确定了适用于制作假目标的相变材料各物性参数的范围，分析了相变材料制作假目标的可行性，并根据所得结果，选取石蜡为研究对象，建立了相变材料模拟金属构件红外特征的理论模型，研究了适用于模拟各金属构件红外特征的相变材料假目标的相关结构参数，得出了相变材料假目标模拟各金属构件红外特征的理论结果，并对相变材料的导热系数这一物性提出了进一步的改进要求；搭建了假目标实验平台，验证了所建理论模型的准确性；以坦克假目标为研究对象，制作了炮塔、负重轮和前上装甲板三个坦克假目标的关键红外热特征部件，并进行了野外实验，取得了较好的结果；以添加铝肋片作为改进相变材料导热能力的手段，理论研究了此类导热增强型相变材料的相关结构参数对模拟效果的影响，得出了模拟不同厚度钢板红外特征的导热增强型相变材料的结构参数及模拟效果。

According to the geology and well test data of Neopaleozoic tight reservoir in Tabamiao region, we begin with the conventional log response characteristic analysis and extract the classification ratio parameters to visual identify and evaluate reservoir characteristic. That is the lithologic, electric and physical ratio parameters and gas synthetical characteristic exponent.

依据塔巴庙区块上古生界致密储层各种地质、试井成果等的资料，从常规测井响应特征分析入手，提取建立了一套直观识别评价储层特征的分类比值参数，即"四性"测井特征参数：岩性比值参数、电性比值参数、物性比值参数和含气综合特征指数。

Firstly, this paper describes the history and state of the research to the minimal polynomial and the characteristic polynomial and then gives the main methods and its computational complexities for computing the characteristic polynomial and of a constant matrix, the characteristic polynomial of a polynomial matrix and the minimal polynomial of a polynomial.

本文先叙述了对最小多项式和特征多项式的国内外的研究历史和现状，然后给出了已有的计算常数矩阵特征多项式、多项式矩阵的特征多项式和常数矩阵最小多项式的主要算法及其复杂性。

The characteristic of electrohydraulic servo valve includes two respects of the stable state characteristic and dynamic characteristic.

电液伺服阀的特性包括静态特性和动态特性两方面。

Finally these characteristic point calculation a characteristic vector, person face characteristic in the database the vector proceeds to match.

最后把这些特征点计算成一组特征向量，同数据库中的人脸特征向量进行匹配。

In the fluvial deposit environment, the quartz superficial characteristic is primarily by the inferior circle, the conchoidal breakage fracture and the submarine hit pit, revealing the transformation of current to the quartz; In lake-deposit environment, quartz sand superficial characteristic is by primarily abraded edges and parallel cleavage, the quartz maintained the primitive characteristic, indicating the quartz received few transformation of fluent, different quartz grain has their different curve character.

在河流沉积环境，石英砂的表面特征以次圆、贝壳状断口和水下撞击坑为主，显示了水流对石英砂颗粒表面的改造；在湖泊沉积环境中，石英砂的表面特征以多棱角和平行解理面为主，石英砂颗粒保持了原始的特征，表明了石英砂颗粒受到水流的改造比较少。不同沉积环境中石英砂颗粒表面结构特征都具有自己的曲线特征。

New type of water chemistry for utility drum boiler and its principle and characteristic Two kinds of water chemistry's main principle and characteristic are detailedly analyzed. Against the problem of high eroding speed, high Fe content in feed water and boiler water, high scaling speed, short chemical cleaning interval, needing poisonous chemical deoxidant, etc for drum boiler's deoxidization water chemistry and difficulty of using oxidation water chemistry, a new type of water chemistry is put forward on the basis of analyzing the characteristic of whole power station's water steam cycle system, principle of two kinds of water chemistry and their practical effect in every cycle stage. Considering two water chemistry's merit, a new water chemistry called Limited Oxidation Water Chemistry is put forward, which is a local slight oxidization no-deoxidant water chemistry. And the proposed method's principle, control parameter, applying condition, start-lay up and emergency measures are initially calculated and analyzed.

三、新型汽包炉水化学工况的提出及其原理和特点详细分析了国内外现行两大类水化学工况处理的核心原理和特点，针对现行汽包炉还原性水化学工况处理所存在的系统腐蚀速度相对较大、给水和炉水铁浓度高、锅炉结垢速度快、机组酸洗间隔短、无法避免有毒化学除氧剂的使用以及氧化性水化学工况在汽包炉机组上应用的困难等问题，在详细分析电站整个水蒸汽循环系统的特点、两类水工况处理的原理和对循环中各段处理的实际效果等的基础上，综合两者的优点，提出了一种新型的局部轻微氧化性无除氧剂汽包炉水化学工况－"汽包炉有限氧化性水化学工况"处理原理，并初步计算、分析和确定了该种新型水化学工况的主要工艺控制参数、应用条件、启停与紧急情况处理等。

Based on modeling and simulation of the steady characteristic of five-phase hybrid stepping motor driver system with fixed-chopping frequency, constant total current driving and new pentagon winding connection pattern, the paper studies the dynamic characteristic of the system, especially single step response characteristic.

本文在建立绕组接法采用新五边形接法，驱动方式采用恒频斩波恒总流驱动时的五相混合式步进电动机系统的稳态仿真模型的基础上，分析研究了其动态特性，并重点对单步响应特性进行了研究与分析。

Liapunov—Schmidt method is one of the most important method in the bifurcation theory.

Liapunov—Schmidt方法是分叉理论的最重要方法之一。

Be courteous -- even when people are most discourteous to you .

要有礼貌──即使当別人对你最不礼貌的时候。