查询词典 spectral analysis

The fracture analysis includes the macro-fractography and micro-fractography, the experimental analysis of the chemical components, the mechanical properties, and the metallography of drill pipes, and the stress conditions analysis of drill pipes in air drilling.

失效分析内容主要包括断口宏观分析和微观分析，钻杆材料化学成分、力学性能和金相组织试验分析，钻杆在空气钻井过程中受力条件分析等。

In this paper Ⅰ successfully applied these methods to fault diagnosis, and presenting some new innovative machinery fault diagnosis method; First Ⅰ present a new gear wornout fault diagnosis method, this method use the vibration signal's time-frequency attribute and instantaneous phase undulation to accurately detect gear's fault, and by comparing with the traditional frequency domain analysis method, this method reveals that many nonlinear and nonstationary characteristic exist in gear's vibration, this tell us that if we use frequency domain analysis method without pay attention to the signal's characteristic, we could get wrong diagnostic result; Then Ⅰ present a new bearing fault diagnosis method, this method use ATVFD and Hilbert transform to do envelop demodulation,Ⅰ analyze the envelop with time-frequency method and find out that this method is more accurate then traditional method.Ⅰ also explain that the modulation of the fault to the carrier wave may also be non-stationary and nonlinear; Finally Ⅰ present a cylinder pressure measurement method of diesel engine by means of vibration, cylinder pressure is an important parameter of diesel engine fault diagnosis, the pressure measuring is simplified a lot by this method,Ⅰ also use the ATVFD and time-frequency analysis to realize it.

本文中将上述理论方法成功地应用到故障诊断中去，提出了几点创新性的诊断方法；提出了一种齿轮磨损故障诊断的新方法，该方法利用振动信号能量的时频域分布特征与瞬时相位波动特征可以进行精确的齿轮故障诊断，并通过与传统的频域诊断方法的比较，揭示出齿轮振动中存在的明显的非线性与非平稳特征，说明了不加选择地利用频域分析方法进行齿轮故障诊断很可能会得到错误的诊断结果；提出了一种轴承故障诊断的新方法，该方法利用ATVFD分解与Hilbert变换进行包络解调，并对解调得到的包络信号进行时频域分析，可以实现更加准确轴承故障诊断，说明了故障对载波信号的调制往往也是非平稳与非线性的；提出了一种利用振动信号进行柴油机汽缸内压力检测的新方法，柴油机汽缸压力的变化是柴油机故障诊断的重要参数，利用振动方法可大大简化汽缸压力的检测过程，该方法也是综合利用ATVFD分解与时频域分析方法实现的。

Secondly, the paper has carried on the analysis to the millimeter wave blasting fuse near field target characteristic, and has produced a RCS measuring technique. The analysis is that non- atmosphere window triangle wave modulation millimeter wave blasting fuse slip frequency spectrum, which has completed under the triangle wave modulation slip frequency signal time domain and the frequency range analysis.

随后对毫米波引信近场目标特性进行了分析，并给出了一种RCS的测量方法，并系统分析了非大气窗口三角波调制毫米波引信的差频频谱，完成了三角波调制下的差频信号时域和频域分析。

Aiming at the problem of buckling stability capability of box section hoist boom of wheel crane, a complete section of hoist boom is taken as analysis object and buckling instability of the webs is analyzed and researched with the booms of different sectional shapes by applying finite element analysis method. Compared with crane design code (GB3811-83), one piece of plate is taken to calculate buckling stability, the method is easier and more accurate and calculation and analysis of complicated sectional shapes are easy to conduct.

针对轮式起重机箱型起重臂的抗屈曲失稳能力问题，采用有限元分析方法，取起重臂截面半波长段作为分析对象，对相同工况不同截面形状的起重臂的屈曲失稳情况进行分析研究，相对于起重机设计规范(GB3811-83)给出的取一块板进行屈曲计算要快捷、准确得多，而且也容易完成对复杂形状截面的计算分析。

First, this paper presents three girders model with double cable planes which main girder and side girder is connected by rigid arms, analyzes the dynamic characteristic of Yonghe cable-stayed bridge and obtains its natural vibration modes (i.e., frequency, damping values and the mode shapes ) by ANLSIS structural analysis program and uses these parameters as dynamic dactylogram of the intact case of cable-stayed bridge. Using the passage of random as the ambient vibration ,the dynamic properties of Yonghe Bridge is measured and the modal parameter of its 15 years after is identified and used as dynamic dactylogram of the damaged case. By the finite element analysis and locale vibration test, damaged and undamaged modal parameter is analyzed and curvature mode shape, which is sensitive to damage state, is introduced as possible candidate for identifying and locating damage in the cable-stayed bridge. Selecting the branch of part measured point from modal parameter, this paper deduces the damaged index which can detect the possible damaged location of the cable-stayed bridge deck and identifies the damaged region and degree for Yonghe Bridge. For the purpose of structural condition monitoring in in-situ , from another viewpoint, this paper introduces the method called the best optimization vector to detect damaged location and degree. The accuracy and reliability of the method presented in this paper are demonstrated by static analysis and test and the healthy state of Yonghe Bridge can be evaluated.

建立了双索面通过刚臂与主梁及边梁相连的三梁式力学模型，采用ANSYS结构分析程序对永和斜拉桥进行动力分析，对其振动模态参数进行识别，以此作为斜拉桥完好状态下的动力&指纹&；采用自由交通流作为环境振源，对永和斜拉桥动力特性进行测试，识别出永和斜拉桥使用15年后的模态参数，确立了破损状态下的动力&指纹&；利用有限元分析、现场振动测试，对破损前后的模态参数进行分析，提取对破损状况较敏感的模态曲率作为斜拉桥破损诊断的参数；并从模态参数中选取部分点的分量，导出可以指示斜拉桥桥面大概损伤位置的Index损伤指标，识别出斜拉桥发生破损的区段及破损程度；考虑大型斜拉桥在线监测要求识别破损的具体位置，从另一角度提出采用最优矢量法具体确定破损发生的位置及程度；为验证本文研究成果，对永和斜拉桥进行静力分析及静力测试，对其健康状况提出可靠的评价。

This article seeks to analyze the current situation summarizing the results of analysis of the characteristics of e-commerce on the basis of the importance of subjectivity, and a comprehensive analysis of the trends under the principle of the basic features of e-commerce, as well as from the market, the seller, the buyer, the whole four perspective on e-commerce features derived from an analysis of the induction, and a more comprehensive e-commerce into this new business model with features.

本文力求在归纳分析目前已有的电子商务特点分析成果的基础上，在重要性、主体性、趋势性和全面性分析原则下，对电子商务的基本特点以及从市场、卖方、买方、整体四个视角对电子商务的衍生特点进行了一个归纳分析，进而比较全面的归纳了电子商务这一全新商务模式具有的特点。

The biggest characteristics in this paper is using independent quantitative range analysis and variance analysis of orthogonal experiment to analyze die casting defects, base on these analysis, detect the weight of each process parameter to die casting defects, then synthetically think over the influence of whole casting quality by the weight of every die casting defect, to balance and choose the level of casting process parameter for seeking the whole quality optimization of casting.

本文最大的特点是将各压铸缺陷进行独立量化的正交实验极差分析和方差分析，通过这些分析可知各工艺参数对此铸造缺陷的影响权重，然后综合考虑各铸造缺陷对轮毂铸件整体质量的影响权重，权衡和舍取工艺参数的水平，以达到铸件整体质量的最优化。

This article uses the following methods: qualitative analysis and quantitative analysis of a combination of methods; literature analysis.

本文的研究方法主要是：定量分析与定性分析相结合的方法；文献分析法。

In this paper, a case analysis and the Combination of questionnaire analysis, analysis of China's B2C e-commerce online marketing strategy.

本文采用了案例分析法和调查问卷法相结合的分析方法，分析研究我国B2C电子商务的网上营销策略。

The feasibility analysis on the packer's function of sealing,anchoring and supporting has been launched,and the contact finite element analysis of the middle rubber with four different lengths has been finished,appropriate length of the middle rubber has been got,and a foundation has been laid for analysis of rubber combination.

开展了水平井酸化封隔器实现密封、支撑、锚定功能的可行性分析，完成了四种长度的中胶筒接触有限元分析，得到了合适的中胶筒长度，为组合胶筒地分析奠定了基础。

The witness also told the jury at the Royal Courts of Justice in London that he saw a paparazzo fighting with a member of the public who was trying to stop him taking pictures in the minutes before the emergency services arrived.

他还告诉在伦敦皇家法庭的陪审团，在急救服务到来之前，他当时看见一个狗仔队正和一群阻止他拍照的人打架。

The entire N／C program on a tape is made up of an accumulation of these successive data blocks.

纸带上的整个数控程序由这些连续数据单元连接而成。