曲率轴

词组短语

axis of curvature

与曲率轴相关的网络例句 [注：此内容来源于网络，仅供参考]

Methods(1)4 cities were chosen randomly according to their economic status and geographical location.(2)An autorefractor was used to detect the diopter in the preschool children from 20 kindergartens randomly selected from each of the 4 cities.(3)1%atropine ointment was applied to the c onjunctival sac of the children with suspect myopia for 3 days and the refractio n of light in their retina was then examined by a barred beam skiascope.(4)The eye axis and corneal curvature of the myopic children were measured.(5)The diop ter,eye axis,and corneal curvature were examined every 6 months during 1-year f ollow-up after the diopter was properly rectified.

(1)依经济状况和地理位置按随机原则抽取4市县；(2)从4市县中各随机选择20间幼儿园，对所抽取的在园学龄前儿童用自动屈光仪进行屈光筛查；(3)可疑近视患者予以1%阿托品眼膏涂双眼3d，由专人用带状检影镜进行视网膜检影验光；(4)确诊为近视的患者自愿进行角膜曲率和眼轴测量；(5)近视患者经适当的屈光矫正后，按要求进行为期1年的前瞻性随访，每半年进行1次屈光状态、角膜曲率和眼轴的检测。

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。

The results show that structure curvature is negatively related to coalbed gas content,relative gas emission rate,outburst gas and coal amounts which reflect No15 coalbed of Ji is above the neutral plane of folds.That is,the No15 coalbed of Ji Group is compressed in incline and is tensed in anticline,and the higher structure curvature is,the higher stress is.

结果表明，构造曲率与瓦斯含量、瓦斯相对涌出量、突出瓦斯量、突出煤量呈负相关关系，反映研究区己15煤层位于褶皱中和面以上，即煤层在向斜轴部受挤压而背斜轴部受拉张，正曲率值反映煤层受到拉张应力作用，负曲率值反映煤层受到挤压应力作用，曲率绝对值越大，受力越大。

This article that focuses on the systematic and in-depth research in the current primal problem about abnormal burst pressure reservoir depress burst pressure has procured following main fruits:1 It forms the method which could obtain massive vertical static state mechanics parameters.2 In a foundation of acquisition of rock mechanics parameters,apply bent lamella that as mechanical model along with characteristic of actual geologic characteristics to analysis curvature for anticlinal strcture, get homologous tectonic stress value throug relation between the curvature and stress and different principal curvature in anticlinal structure,consequently set up laminational stress model for anticline reservoir. The block lamination for existed fracturing date has formed method of setting up mechanical model of lamination terrestrial stress by abtaining the block tectonic stress coefficients which are got by complex utilization test, laboratory test and fracturing date playback.3 Analysesing the main reason which lead to high burst pressure by considering the characteristic of reservoir geology,reservoir,and rock mechanics and reservoir damage,etc.Establishing burst pressure quantitative prediction model which provide gist for depressing construction risk and optimizing construction craft under the condition of open hole completion ,gun-perforated completion and damaged reservoir.4 Provding theoretical basis for interpreting acidification pretreatment which could depress busrt pressure by finding the relation between the influencing factors and rock machanics parameters and analysing the factors that have effect on rock mechanics parameters. Expounding the mechanism of reaction of mixed monomineral and acid from the angle of microcosmic element, evaluating quantitatively acid sensilility of different kinds of mineral effectively, and determing the first-order reaction dynamical equation of each mineral.5 Revealing rock mechanics property chage as a result of acid flooding in different condition by sandstone traumata experiment in different temperatures which combined with rock mechanics triaxial stress experiment.6 Associating damage mechanics with sandstone acidizing, established sandstone damage mechanics model in the foundation of the recognition on the rock mechanics parametric variation which is caused by acid-rock reaction in both macroscopic view and microscopic view ,also demonstrated those processes and quantitative estimated the acid busrt pressure to direct the site operation.

本文针对目前异常破裂压力储层降低破裂压力的主要问题展开较为系统和深入的研究，取得了以下主要成果：1形成了利用测井资料，结合室内岩芯测试结果，获取静动岩石力学参数的相关性特征，从而获得纵向上大量静态力学参数的方法。2在获取了岩石力学参数的此基础上，利用弯曲薄板作为力学模型，结合区块实际地质特征对背斜构造进行曲率分析，通过曲率与应力的关系，利用背斜构造不同部位的主曲率求得相应的构造应力值，从而建立起背斜储层的分层应力模型；对已有压裂资料的区块分层，形成了综合利用测试、室内实验、压裂资料反演获得该区块构造应力系数，建立起分层地应力的力学模型的方法。3综合考虑储层地质、油藏、岩石力学特性和储层伤害等因素，分析造成高破裂压力的主要原因，综合利用岩石力学、弹性力学等知识，建立了裸眼完井、射孔完井条件下以及储层受到伤害后的储层破裂压力定量预测模型，为降低施工风险和优化施工工艺提供了依据。4完成了物性、岩性影响岩石力学参数的因素分析，找出了各影响因素和岩石力学参数之间的关系，为从机理上解释酸化预处理降低破裂压力提供了理论基础；从微观元素的角度阐述了单矿物与酸反应的机理；并在此基础上，有效评价了各种矿物的酸敏感性，定量确定了岩石中各矿物的一级反应动力学方程。5完成了不同温度下的酸液类型、酸液浓度、注酸量等一系列砂岩损伤实验，结合岩石力学三轴应力实验，系统揭示了在不同条件下注酸而引起的岩石力学性质变化。6将损伤力学与砂岩酸化相结合，在宏观、微观两个方面认识酸岩反应引起岩石力学参数变化基础上，建立了砂岩损伤力学模型，并对其进行验证，在此基础上定量计算酸化后的破裂压力，有效指导现场施工

Distributions of corneal curvature With the formula 〓 Sin〓αwhich is about the curvatures of oblique meridians on toric surface, the theoretical values of anterior, posterior and total corneal radius of curvature of the oblique meridians were obtained.

3角膜曲率分布根据托力克面斜轴子午线曲率F'计算公式〓，确定角膜前、后表面斜轴子午线曲率及斜轴子午线总角膜曲率的理论值，并通过分析该理论值与实测值之间的一致性，明确角膜曲率分布特征。

Experimental Research on FBG Sensor for Large Curvature Detection;2. For large curvature arch, the neutral axis does not pass through the centroidal line of the cross-section, so the moment of inertia is not consistent with the second moment of area.

大曲率拱中，截面形心轴与中性轴不重合，其截面抗弯惯性矩与不考虑曲率影响的截面面积二阶矩有一定的差别；当截面尺寸相对拱弧长来说较大时，此时拱为深拱，剪切变形的影响不能忽略。

Diopter, corneal curvature, depth of anterior chamber and the axial length of the eyes were measured. We calculated the concordance of hyperopia, intrapair correlation coefficient and heritability index of monozygous and dizygous twins.

调查了同卵和异卵双生子的屈光度、角膜曲率半径、前房深度、眼轴长度，计算了远视的一致率，同卵和异卵双生子的组内相关系数及遗传指数等项目，证实远视眼是一种多因子遗传病，它的发生除了与多个遗传性状如角膜曲率半径、前房深度、眼轴长度等有关外，还与环境因素有关。

Objective: To determine a accurate method to measure ocular axial length,anterior chamber depth lens thickness and keratometry by calculating degrees of intraocular lens demand.

目的：通过对人眼球轴长、前房深度、晶体厚度和角膜曲率的测定，探讨它们之间的相关性，并把握如何精确测定眼球轴长、角膜曲率来保证人工晶体的正确计算。

Ip and Loftus 5 demonstrated the competency of an inclined end mill machining strategy on 3-axis machines in producing low curvature surfaces.

叶和洛夫特斯5展示一个斜立铣刀加工的战略能力 3，生产低曲率轴机床表面。

Methods Comparative study on preoperative and postoperative conditions of the eyesight, corneal curvature, axis oculi and reflection was conducted.

对63例水平斜视进行术前视力、角膜曲率、眼轴及眼的屈光度测量，进行术后1月、3月的视力、角膜曲率、眼轴及眼的屈光度测量，并进行对比分析。

与曲率轴相关的网络解释 [注：此内容来源于网络，仅供参考]

curvature ametropia：曲率性屈光不正

axial ametropia 轴性屈光不正 | curvature ametropia 曲率性屈光不正 | index ametropia 指数性屈光不正

axial ametropia：轴性屈光不正

ametropia, AM 屈光不正 | axial ametropia 轴性屈光不正 | curvature ametropia 曲率性屈光不正

double-curvature arch dam：双曲拱坝

变曲率轴颈:Curvature-changing claw | 双曲拱坝:double-curvature arch dam | 振型曲率比:mode shape curvature ratio

axis of curvature：曲率轴

axis of coordinate 坐标轴 | axis of curvature 曲率轴 | axis of ordinates 纵坐标轴

curvature hypermetropia：曲率性远视

axial hypermetropia 轴性远视 | curvature hypermetropia 曲率性远视 | index hypermetropia 指数性远视

curvature hypermetropia：曲率性近视

axial hypermetropia 轴性近视 | curvature hypermetropia 曲率性近视 | index hypermetropia 指数性近视

paraxial：近轴

这些包括放置一个"solve"于成像面的特殊曲率或厚度上,在(或至少接近)近轴(paraxial)成像的位置上时,或要求一个渴望的放大率(magnification)或焦距长(focal length)时.