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.

理論分析和試驗(yàn)研究表明： 1球軸承振動(dòng)是鋼球—滾道接觸副中的各種摩擦學(xué)作用引起的免费观看在线无码一区，具有摩擦動(dòng)力學(xué)的本質(zhì)，任何對(duì)接觸副的摩擦學(xué)特性有影響的因素都將對(duì)球軸承的振動(dòng)和噪聲特性產(chǎn)生影響熟女口爆； 2中心軸向載荷作用下，載荷增大使球軸承的固有振動(dòng)頻率升高，載荷越大同樣的載荷增幅引起的頻率升幅減小欧美中文字幕版，足夠大的中心軸向載荷作用下載荷的變化對(duì)球軸承振動(dòng)的頻率特性不會(huì)產(chǎn)生明顯的影響玖玖爱视频在线； 3軸向和徑向聯(lián)合載荷作用下先锋资源综合，徑向載荷不大時(shí)球軸承振動(dòng)的固有頻率基本不變，但是可能引起變剛度激勵(lì)的非線性振動(dòng)无码中文人妻在线二区，出現(xiàn)新的頻峰人人爽,人人操，過大的徑向載荷將使部分鋼球脫離接觸，使球軸承的振動(dòng)和噪聲呈現(xiàn)不穩(wěn)定狀態(tài)日本黄色免费网站在线观看； 4潤(rùn)滑對(duì)球軸承的振動(dòng)和噪聲特性有重要的影響国精品无码一区二区三区免费视频，良好的潤(rùn)滑對(duì)振動(dòng)有明顯的抑制作用久久久国产精免费视频，潤(rùn)滑不充分時(shí)，振動(dòng)和噪聲的水平會(huì)有明顯增高免费在线网站你懂得，一定條件下還會(huì)激發(fā)接觸副中的諧振野外A片黄色網址，發(fā)出嘯聲，造成接觸表面的傷害91福利在线精品国产，無潤(rùn)滑干接觸時(shí)先锋影音AV网站，短時(shí)的運(yùn)轉(zhuǎn)就會(huì)損傷接觸副表面美女扒开腿让我爽视频软件网站，使振動(dòng)和噪聲迅速增大欧美一级特黄大片色欧美精，并隨時(shí)可能引發(fā)嚴(yán)重的磨損和卡滯失效影音先锋zyz；接觸副潤(rùn)滑良好時(shí)深夜A级毛片五月综合婷香久久，油膜的"剛化效應(yīng)"使球軸承振動(dòng)的固有頻率有所提高，潤(rùn)滑劑中含有彌散性污濁時(shí)国产一区免费视频，振動(dòng)的幅度總體升高，但彌散性污濁不會(huì)改變球軸承振動(dòng)的頻率特性亚洲午夜精品视频；浙江大學(xué)博士學(xué)位論文：球軸承振動(dòng)的研究 5低速時(shí)，球軸承振動(dòng)的基本特征呈現(xiàn)不穩(wěn)定狀態(tài)九一人人操人人摸，隨著轉(zhuǎn)速的提高，球軸承振動(dòng)的頻率特性趨于穩(wěn)定中文字幕精品一区二区日本，固有頻率頻峰升高女优网址； 6理論分析表明日韩国产一区，干接觸時(shí)鋼球和滾道表面波紋度的某些諧波分量能激勵(lì)球軸承的振動(dòng)一级黄色免费无码，振動(dòng)的幅值與諧波幅值成正比黄片美女18岁，實(shí)際球軸承中鋼球的分布不可能完全均勻老年人一级毛片黄片，波紋度的激勵(lì)作用會(huì)隨時(shí)發(fā)生；潤(rùn)滑接觸的分析表明欧美爱性真人在线视，波紋度的任意諧波分量均能激勵(lì)球軸承的振動(dòng)8×8x永久华人免费网址入口； 7球軸承的幾何和結(jié)構(gòu)參數(shù)分析表明啪啪啪试看乱码，球軸承尺寸越大国产168页视频，徑向国产操逼免费看、軸向和角振動(dòng)的固有頻率越低国产啪精品视频网站；鋼球中心圓直徑增大，球軸承的徑向和軸向振動(dòng)的固有頻率基本不變欧美性爱三级影片免费在线看网站，角振動(dòng)的固有頻率有所上升欧洲黑人黄片，振動(dòng)的幅頻特性基本不變下载安卓版蘑菇影视最新版；徑向游隙加大使球軸承的徑向振動(dòng)固有頻率降低无码黄片观看不卡，軸向和角振動(dòng)的固有頻率有所升高一级A爱在线，徑向振動(dòng)幅頻特性的幅值升高，而軸向和角向降低婷婷五月国产精品一区二区；鋼球的數(shù)量增多使球軸承振動(dòng)的固有頻率上升，幅頻特性的幅值下降综合天天干，徑向振動(dòng)的幅值下降最為明顯成人在线观看网站；外圈溝曲率半徑系數(shù)增大使球軸承徑向振動(dòng)的固有頻率升高，軸向和角振動(dòng)的固有頻率降低国内偷拍视频一区，徑向幅頻特性基本不變欧美日韩国产精品，軸向和角向幅頻特性幅值升高；內(nèi)圈溝曲率半徑系數(shù)增大使徑向在线看的a片、軸向和角振動(dòng)固有頻率均下降国产精品人爱超碰资源，振動(dòng)幅頻特性的幅值均有升高； 8試驗(yàn)對(duì)比表明偷拍亚洲，傳感器采用探針式安裝時(shí)在线www.av，由于探針接觸副接觸特性的影響，鋇(量得到的球軸承振動(dòng)信號(hào)有失真欧美一级婬片欧美人妻，采用專門設(shè)計(jì)和制作的試驗(yàn)球軸承久久久久久久久久久久久久久精品，以固定式安裝加速度計(jì)午夜性爱视频在线，首次測(cè)量得到了球軸承振動(dòng)的真實(shí)信號(hào)，通過對(duì)振動(dòng)信號(hào)的分析黄黄的视频网站，驗(yàn)證了球軸承振動(dòng)的理論模型www.aigou1314.com； 9)基于時(shí)間序列分析的AR模型適用于大樣本球軸承振動(dòng)信號(hào)的分析，以樣本長(zhǎng)度的均方根值作定階上界黄色视频在线观看com，F(xiàn)PE做判階準(zhǔn)則吹朝A片视频日本一区二区，給出的AR譜光滑，頻率分辨率高欧美性爱视频一区在线观看，是球軸承振動(dòng)分析的簡(jiǎn)便而可靠的手段女生奶头视频； 10以時(shí)頻域分析的小波包變換分析球軸承異音信號(hào)能夠比較好地定位和聚焦異音發(fā)生的時(shí)間，時(shí)間間隔孕妇三级片在线观看，頻率范圍A级毛片中文字幕完整版，同樣是球軸承振動(dòng)分析的可靠的手段，可用作球軸承故障診斷技術(shù)欧美激情2。

Load spectrum determination of tubing inwall proves the tubing is acted by the axial alternating load in a rod pumped well, and all the fractures are located at the root of the tooth.

油管內(nèi)壁載荷譜測(cè)定進(jìn)一步明確了油管在工作狀態(tài)下承受軸向拉-拉交變載荷黄色网站视频你懂得，其斷裂部位全部在應(yīng)力集中的齒根處。

Axial-system torsional oscillation Hopf ramification Nonlinear dynamic state Characteristic root analysis

軸系扭振苍井空全集百度影音； Hopf分歧毛片国产一国产AN毛片；非線性動(dòng)態(tài)；特征根分析

The results show that, firstly, Stellera chamaejasme L, which rely on their developed axial root system in the 10～40cm soil layer to occupy the competitive priority of volume, length, surface area and so on, in the case of their adaptive faculty to poor surroundings resulting from fruit picking, trampling and overgrazing as well as with the phenomenon of restrained growth among various plants, gradually become the dominant plant in the herbaceous community; secondly, this kind of degraded grassland has not displayed any general characteristic of degradation such as surface exposure, accumulative quantity of vegetation reduced, water loss, soil erosion and so on, therefor, it should be dealt with distinguishingly; thirdly, if"Stellera chamaejasme L Killer"and"Oxytropis ochrocephala Killer"invented by CAS are taken advantage of respectively in the bloom period of Stellera chamaejasme L and at the beginning of florescence of Oxytropis ochrocephala bunge by ultra-low volume spray of 1. 05L/hm〓 and 1. 35～165L/hm〓 dosage separately, the death rates of poisonous herbs may achieve above 95% and 92% correspondently; fourthly, this technology with the characteristics of high work efficiency, exclusive selectivity and convenient operation, is safe to non-target plants and other animals, and has no toxic or side-effect to environment; furthermore, an execution of"Stellera chamaejasme L Killer"spray and a two-year grazing prohibition can be effectively applied on degraded grasslands of"Weed and Poisonous plants Type".

結(jié)果表明：狼毒憑借發(fā)達(dá)的軸根系在10～40cm土層中形成的體積日韩高清第一页、長(zhǎng)度性色av无码一区二区、表面積等競(jìng)爭(zhēng)優(yōu)勢(shì)，以及對(duì)采食疯狂做受XXXX特大、踐踏毛片三A级无码AV一区久久久、過度放牧所形成的不良環(huán)境的適應(yīng)能力和異株克生現(xiàn)象的存在，逐步成為草群中的優(yōu)勢(shì)植物99久久久精品免费人妖；毒雜草型退化草地沒有表現(xiàn)出地表裸露杭州最疯狂一级毛片视频、植物蓄積量減少、水土流失等一般性退化特征男女超爽无遮挡全过程免费，對(duì)該類草地的治理應(yīng)區(qū)別對(duì)待欧美国产另类；應(yīng)用中科院研制的'滅狼毒'和'滅棘豆'分別在狼毒盛花期和黃花棘豆初花期，以1.05L/hm〓免费毛片视频网、1.35～165L/hm〓的施用量超低容量噴霧亚洲欧美激情小说，毒草的死亡率可達(dá)到95％、92％以上玖玖在线黄色视频；該技術(shù)具有工效高、選擇性專一欧美黄片视屏、滅效高人人操人人干亚洲精品、操作簡(jiǎn)便国产极品黄色，對(duì)非靶標(biāo)植物和其它動(dòng)物安全，對(duì)環(huán)境無毒副作用的特點(diǎn)亚洲日韩欧美综合制服丝袜；采用噴施'滅狼毒'+短期禁牧措施可以免费在线观看的黄色视频的网站，可以有效治理毒雜草型退化草地。

Methods:Twenty-three tooth of 19 patients were examined by using ProMax lateralal sagittal axial panoramic tomographs before the teeth were extracted or orthodonted to assessment location and shape of dental root.

隨著影像學(xué)檢查技術(shù)的發(fā)展靑青草视频免费播放一色，全景機(jī)的操作性能及程序化控制水平明顯提高91免费a视频，可進(jìn)行多種部位投照[1]。ProMax數(shù)字化X光機(jī)可以投照頜骨牙列斷層片又大又长黄色视频。

At the same time, gene interaction was observed in some of characters, transgressive segregation gene interaction was observed in polygenes controlling length of axial root and thickness of root base （ 1cm）, complementary gene interaction was significantly detected in nodule number of lateral root and dry weight of lateral root and nodule number of lateral root, but not detected or significant in the others.

控制主根長(zhǎng)性狀的多基因間存在互作插一插视频，互作方式為重疊作用；控制主根粗（3cm）性狀的基因間也存在一定的重疊作用二级黄片视频，但是作用不明顯亚洲国产精品色一区二区三区色牛；控制其他性狀的基因都存在互作，表現(xiàn)為互補(bǔ)作用美国无码一级视频，但互補(bǔ)作用的強(qiáng)弱有差異最新99在线拍视频。