验证试验
- 与 验证试验 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Using Latin square test, the effect of geometrical parameters on the characteristics of non-overload sewage pump was studied, and the effecting principle of geometrical parameters on efficiency, maximum brake horsepower and its location were researched, the major and minor factors affecting these performance were found out by way of variance analysis, the correction of equation on maximum brake horsepower and its location were also tested.
用正交试验法研究了各几何参数对无过载排污泵性能的影响,探索了各几何参数对效率、最大轴功率值及其位置的影响规律,并通过方差分析找到了影响这些性能的主要因素和次要因素,验证了无过载排污泵最大轴功率值及其位置公式的正确性,根据试验结果对模型泵提出了进一步设计方案,本试验结果对无过载排污泵水力设计有一定的参考价值。
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Seventhly, a series of experiments and projects were carried out for verifying the previous theory. First, the cable force control test of reticulated shell-string structure in 2.2m×4.6m was conducted using the arithmetic presented in the paper. Second, the numerical analysis during construction, the adjustment of cable forces and the changing of cable of the Beijing North Railway Station were conducted.
为了进一步验证本文前几章有关预应力空间钢结构索张拉计算方法的正确性,本文进行了一系列的试验研究,包括:用提出的基于索原长反分析法对一2.2m×4.6m的小型张弦网壳进行索张拉成形的试验研究;对北京北站进行了模型施工过程分析、模型索张拉力的调整、换索试验研究。
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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。
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The effect of tribology factors on bearing vibration is studied experimentally. AR model and WPT are used to processing the normal arid abnormal signals. The results are as follows:1. The vibration of ball bearings is caused by the tribology action of contact pairs of ball and ring races and has the essential of tribo-dynamics. Any factors affecting the tribology characteristics of contact pairs will affect vibration and noise of bearings consequently.2. Vibration characteristics of bearing keep almostly unchanged with the increasing of axial load expecting the increasing of nature frequencies. When radial load increasing with axial load unchanged, nature frequencies keep unchanged but some new vibration peaks appears in the spectrum.3. Vibration amplitudes are damped and nature frequency are enhanced with sufficient lubrication. Vibration and noise of bearings increase obviously and roar can happen and the contact surfaces scratch slightly under insufficient and unclean lubrication state. Bearing will be disabled in a few minutes without any lubrication.4. Bearing vibration is unstable under low speed. With the speed increasing, the vibration become stable and natural frequencies increase slightly but the amplitudes increase apparently.5. Bearing vibration can be excited only by some harmonics ofwaviness without lubrication and by all harmonics with lubrication based on the theoretical analysis.6. The nature frequencies of ball bearings decrease with the increasing sizes. When international clearance increasing, nature frequencies decrease in radial and increase in axial and angular and the amplitudes increase in radial and decrease in axial and angular. When the number of balls increasing, nature frequencies increase and amplitudes decrease. When the pitch diameter increasing, axial nature frequency increase and others nearly keep no change. When outer race groove curvature radius increasing, nature frequencies increase in radial and decrease in axial and angular and amplitudes keep no change in radial and increase in axial and angular. When inner race groove curvature radius increasing, nature frequencies decrease and amplitudes increase.7. The distortion in amplitude and frequency components of bearing vibration signals picked up by the present probe measurement method is founded and right conclusions cannot be achieved by the signals. When accelerometer is rigidly screwed with steel stud onto a flat outer surface of a ball bearing, vibration signal can be got without distortion and the reliability of research on bearing vibration is assured.8. AR model is suitable for large samples of bearing vibration signals, square root of length of samples can be used as the upper limitation of order determination and the FPE order selection criterion is effective. Many advantages of AR spectrum are founded over the classical based on FFT.9. Time-Frequency analysis is necessary for abnormal noise of ball bearings. WPT overcomes the principle shortcomings of STFT and proved to be a best tool to process the abnormal signals.
理论分析和试验研究表明: 1球轴承振动是钢球—滚道接触副中的各种摩擦学作用引起的,具有摩擦动力学的本质,任何对接触副的摩擦学特性有影响的因素都将对球轴承的振动和噪声特性产生影响; 2中心轴向载荷作用下,载荷增大使球轴承的固有振动频率升高,载荷越大同样的载荷增幅引起的频率升幅减小,足够大的中心轴向载荷作用下载荷的变化对球轴承振动的频率特性不会产生明显的影响; 3轴向和径向联合载荷作用下,径向载荷不大时球轴承振动的固有频率基本不变,但是可能引起变刚度激励的非线性振动,出现新的频峰,过大的径向载荷将使部分钢球脱离接触,使球轴承的振动和噪声呈现不稳定状态; 4润滑对球轴承的振动和噪声特性有重要的影响,良好的润滑对振动有明显的抑制作用,润滑不充分时,振动和噪声的水平会有明显增高,一定条件下还会激发接触副中的谐振,发出啸声,造成接触表面的伤害,无润滑干接触时,短时的运转就会损伤接触副表面,使振动和噪声迅速增大,并随时可能引发严重的磨损和卡滞失效;接触副润滑良好时,油膜的"刚化效应"使球轴承振动的固有频率有所提高,润滑剂中含有弥散性污浊时,振动的幅度总体升高,但弥散性污浊不会改变球轴承振动的频率特性;浙江大学博士学位论文:球轴承振动的研究 5低速时,球轴承振动的基本特征呈现不稳定状态,随着转速的提高,球轴承振动的频率特性趋于稳定,固有频率频峰升高; 6理论分析表明,干接触时钢球和滚道表面波纹度的某些谐波分量能激励球轴承的振动,振动的幅值与谐波幅值成正比,实际球轴承中钢球的分布不可能完全均匀,波纹度的激励作用会随时发生;润滑接触的分析表明,波纹度的任意谐波分量均能激励球轴承的振动; 7球轴承的几何和结构参数分析表明,球轴承尺寸越大,径向、轴向和角振动的固有频率越低;钢球中心圆直径增大,球轴承的径向和轴向振动的固有频率基本不变,角振动的固有频率有所上升,振动的幅频特性基本不变;径向游隙加大使球轴承的径向振动固有频率降低,轴向和角振动的固有频率有所升高,径向振动幅频特性的幅值升高,而轴向和角向降低;钢球的数量增多使球轴承振动的固有频率上升,幅频特性的幅值下降,径向振动的幅值下降最为明显;外圈沟曲率半径系数增大使球轴承径向振动的固有频率升高,轴向和角振动的固有频率降低,径向幅频特性基本不变,轴向和角向幅频特性幅值升高;内圈沟曲率半径系数增大使径向、轴向和角振动固有频率均下降,振动幅频特性的幅值均有升高; 8试验对比表明,传感器采用探针式安装时,由于探针接触副接触特性的影响,钡(量得到的球轴承振动信号有失真,采用专门设计和制作的试验球轴承,以固定式安装加速度计,首次测量得到了球轴承振动的真实信号,通过对振动信号的分析,验证了球轴承振动的理论模型; 9)基于时间序列分析的AR模型适用于大样本球轴承振动信号的分析,以样本长度的均方根值作定阶上界,FPE做判阶准则,给出的AR谱光滑,频率分辨率高,是球轴承振动分析的简便而可靠的手段; 10以时频域分析的小波包变换分析球轴承异音信号能够比较好地定位和聚焦异音发生的时间,时间间隔,频率范围,同样是球轴承振动分析的可靠的手段,可用作球轴承故障诊断技术。
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To accelerate the widespread of Synchronous Chip Seal and improve the operation quality of Synchronous Chipsealer, key techniques which influence the operation quality is studied detailedly, including the control of distributing quality, the dynamics characteristics of hydraulic system and the spray characteristics of asphalt nozzle of Synchronous Chipsealer.1 The factors which influence Synchronous Chip Seal quality are studied. Fiducial probability of simultaneous distribution density is advised to be used in evaluating the distribution bias and standard deviation of asphalt and aggregates simultaneously, which is more advanced than the single index evaluation method used before.2 The volume efficiency formula of asphalt pump is revised after analyzing the data of volume efficiency with mathematical statistics, which is helpful to match the asphalt spray system and control the flow out of asphalt pump accurately. With equation deduction and experiment, dynamic of hydraulic system used in Synchronous Chipsealer is studied, which lay the theory foundation on improving the stability and efficiency from design and controlling.4 Simulation on hydraulic system used in Synchronous Chipsealer is done with AMESim; the results indicate that multi-circle parallel connected hydraulic system with constant pressure power is better than that with load-sensing pressure power at present, because the latter will oscillate when the multi circles work at the same time. This conclusion has been proved during the debug of Synchronous Chipsealer.5 Asphalt nozzle characteristics, such as flat jet shape, flow distribution, are studied with experiment, the results indicate that cross quality of asphalt distributing is not increased linearly follow the increase of fan overlap level, the best point usually exists between two whole overlap level, asphalt distributing quality is better than±4% at the 2.5 overlap level, meets the superior specified in standard; The distribution quality of Synchronous Chipsealer can be increased by spray asphalt of different flow rang with nozzle of different diameter
为了加快同步碎石封层技术的推广,提高同步碎石封层设备的作业质量,本文对同步碎石封层设备作业质量的影响因素与控制方法、液压系统的动力学特性和沥青喷嘴的喷洒特性等关键技术进行了深入细致的研究:1研究了影响同步碎石封层作业质量的因素,提出了采用联合密度分布置信概率对同步碎石封层中沥青洒布量和碎石撒布量的系统偏差和标准差指标进行综合评价的方法,克服了传统评价方法只能对单一指标进行评价的缺陷;2采用数理统计的方法,研究了沥青泵的容积效率特性,修正了沥青泵容积效率公式,为沥青喷洒系统的匹配和沥青泵出口流量的精确控制提供了依据;采用数理方程推导与试验相结合的方法,研究了同步碎石封层设备液压系统的动力学特性,为从设计和控制的角度提高同步碎石封层设备液压系统的稳定性和效率奠定了理论基础;3运用AMESim软件对采用负载敏感控制和恒压控制的两种同步碎石封层设备液压系统进行仿真,结果表明:负载敏感控制的并联液压系统在多回路同时工作时,由于液压泵排量控制参考压力不稳定,容易引发液压系统振荡,恒压控制的并联液压系统是目前技术条件下比较理想的同步碎石封层设备工作装置驱动方案;该结论亦通过同步碎石封层设备装机试验得到了验证。4采用试验的方法对沥青喷嘴的喷洒特性进行了研究,结果表明:沥青洒布的横向精度并不是随着喷洒扇面重叠度的增加线性增加,其最高点通常出现在二个重叠度之间的"半重叠位置","2.5重叠"洒布时,沥青的横向洒布精度≤±4%,可以达到国家相关标准中的优级标准;同步碎石封层设备还可以根据不同洒布量情况下的流量需求,采用不同通径的喷嘴进行喷洒,提高沥青洒布精度。
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Results revealed that the large side insulation of the stator bar in slot is available for ultrasonic pulse-echo testing; Coupling transducer on the surface of a practical stator bar could minimize the influence on the measurements of velocity, contributing no destructivity of the ultrasonic testing for stator insulation; The simultaneity of same velocity and higher attenuation can be used to detect insulation delamination from conductors; Compared with the wide sides of the bars in slot, the short sides of the bars near the exit from slot and the end bars had a same velocity and a higher attenuation; The velocity might be exactly measured on the shot sides of the bars near the exit from slot and the end bars, while the attenuation might not, which were examined though filed tests; V min decreased greatly and V av decreased slightly with the service time of the bars.
在实验室对线棒多种结构处的主绝缘和不同运行年数(未老化、16、18 和23年)线棒的主绝缘进行了低频超声反射法检测试验,并进行了现场试验,发现(参见 Hao et al, IEEE DEI, to be published),槽部线棒的宽面绝缘不受换位绝缘的影响,比窄面绝缘更适合超声测量;线棒表面平滑的半导体层减小了耦合剂对超声测量的影响,实现了无损性;波速不变而声衰减减小可以检测线棒出现绝缘与导体脱壳缺陷;出槽口和端部线棒的窄面绝缘与槽部线棒的宽面绝缘相比,声衰减大而波速一致;现场试验验证了波速不受绝缘结构和现场测试条件的影响,而声衰减受以上因素影响很大(参见 Hao et al,中国电机工程学报, Vol.23 No.4); V min 随运行年数明显减小, V av 随运行年数慢慢越小。
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The modal tests of PCB and PCB assembly (free boundary condition and fixed boundary condition) were carried out. The equivalent elastic modulus and damping parameters of PCB can be gained, and the fixed boundary condition of finite element model was also determined. These will help to the following work.Second, drop impact tests of three different heights were carried out. Strains and acceleration responses of PCB were measured. Failed BGA packages of different test conditions were dyeing, and cross section analysis of failed solder joints was conducted.
针对JEDEC标准试件的局限性,提出了设计便于统计学研究焊点可靠性的试验试件的构想,利用有限元模态分析方法确定并验证了用圆形PCB组件替代JEDEC标准试件的可行性;通过一系列模态试验和有限元模态分析,确定了圆形PCB组件的相关试验参数,这不仅为跌落碰撞下PCB组件有限元模拟确定了较为合理准确的有限元模型,而且为正确地评价跌落碰撞下PCB组件的可靠性问题奠定了基础。2。
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The modal tests of PCB and PCB assembly (free boundary condition and fixed boundary condition) were carried out. The equivalent elastic modulus and damping parameters of PCB can be gained, and the fixed boundary condition of finite element model was also determined. These will help to the following work. Second, drop impact tests of three different heights were carried out. Strains and acceleration responses of PCB were measured. Failed BGA packages of different test conditions were dyeing, and cross section analysis of failed solder joints was conducted. It was found in our drop tests that the root cause of lead-free solder joints under drop impact was the combined effect of mechanical shock and PCB bending vibration.
针对JEDEC标准试件的局限性,提出了设计便于统计学研究焊点可靠性的试验试件的构想,利用有限元模态分析方法确定并验证了用圆形PCB组件替代JEDEC标准试件的可行性;通过一系列模态试验和有限元模态分析,确定了圆形PCB组件的相关试验参数,这不仅为跌落碰撞下PCB组件有限元模拟确定了较为合理准确的有限元模型,而且为正确地评价跌落碰撞下PCB组件的可靠性问题奠定了基础。
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At the same time combined with indoor maximum dry density test,this paper discusses the possibility that rock-filling construction quantity .Then data of densification quantity examination under the condition ofdifferent filling material.densification machinery.densification parameter and lay-down thickness are collected as the analytic object. On the basis of making a statistical analysis of experiment data ,supervisory standard and assessment method of settlement difference and settlement ratio that adopted to examine rock-filling embankment construction quantity are put forward systematically At last carrying on settlement observation tests of rock-filling embankment in different construction stage in different layer ,the dependability of assessment method is validated.
同时结合室内最大干密度试验,讨论了表面沉降法作为填石路基施工质量检测手段的可行性和可靠性;然后通过汇总不同填料、不同压实机械、不同压实参数和不同摊铺厚度条件下的压实质量检测数据作为分析对象,在对试验数据进行了统计分析的基础上,较为系统地提出了以沉降沉降差及沉降率作为填石路基施工质量检测指标的评定方法和相应的管理标准值;最后通过对填石路基试验段进行不同填筑时期不同层位的沉降观测试验,验证了评定方法的可靠性。
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The analytical method used in this paper is justified by comparing with country norm form formula results , the result of Franco et al and the result of Yuxiu Wei et al.
综合各因素的影响,应用最小二乘法进行曲线拟合,得到了斜向波和多向波作用于直立堤上的平均越浪量的计算公式、单波最大越浪量的计算公式、单波最大越浪量和平均越浪量的关系式、越波率计算公式以及单波越浪量的统计分布形式,并通过与按照我国规范中斜坡堤越浪量计算公式形式拟合得到的直立堤越浪量公式和俞聿修,魏德彬的试验结果、Franco C,Franco L试验结果的比较来验证本文所采用的分析方法的合理性、试验结果的可靠性,以便于理论研究和工程设计参考应用。
- 推荐网络例句
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The split between the two groups can hardly be papered over.
这两个团体间的分歧难以掩饰。
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This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.
这种做法不仅鼓励了更多的反应,而且减少跟风的可能性。
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The new PS20 solar power tower collected sunlight through mirrors known as "heliostats" to produce steam that is converted into electricity by a turbine in Sanlucar la Mayor, Spain, Wednesday.
聚光:照片上是建在西班牙桑路卡拉马尤城的一座新型PS20塔式太阳能电站。被称为&日光反射装置&的镜子将太阳光反射到主塔,然后用聚集的热量产生蒸汽进而通过涡轮机转化为电力