中值

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。

In the studying of image segmentation, six crucial technologies havebeen developed successfully. 1 In one dimension histogram of original DRimage of luggage, there remain maximum-value wave crest havingapproximately stationary position, and the first minimum to the left of thewave crest performs excellently to be used to get rid of background of DRimage. 2 Open operation, one type of math morphology, is the right idea toerase luggage disturbance in DR image and at the same time, can be retaininteresting region appropriately. 3 After open operation, there are only a few minimums on image histogram, one of which can be to segment image furtherand achieves satisfying result. 4 Method of histogram analyzing and that oferosion performs well in the re-segmentation of conglutinative region in DRimage. 5 Method of image distance switch can ensure Luggage CT sectionautomatically obtained to have rich suspicious region information. 6 Todecompose structure element of math morphology is a way to save a great dealrunning time for automatically discerning interesting regions algorithm,apparently improving implementation efficiency.

在对图像可疑区域分割研究中，主要开发成功以下几项关键技术：1发现原始箱包DR图像的一维直方图中，均具有位置相对稳定的最大值波峰，以波峰左边第一个极小值为分割阈值，去除DR图像背景，效果非常好。2运用数学形态学中的开运算能够非常有效地去除箱子的干扰，同时能够比较好地保留可疑区域。3发现开运算后的DR图像直方图只有若干个极小值点的特点，其中用最大值波峰左边的第二个极小值点进一步分割DR图像，能够更有效地提取箱包中的可疑区域。4运用直方图分析法和腐蚀法，对粘连区域实行再分割，效果较好。5运用距离变换法，能确保自动设定的箱包CT截面包含丰富的可疑区域信息。6运用形态学结构元素分解技术，大幅度减少可疑区域的自动判别算法运行时间，提高算法软件执行效率。

Using nuclear DNA C-values for 539 angiosperms in China, we examined the variation of these values among growth forms and taxonomic groups and the relationship of these values with invasiveness. Mean DNA C-value of the 539 angiosperm species was 4.06 pg. Mean DNA C-value was(1) significantly lower for woody species (1.84 pg) than for herbaceous species(5.02 pg);(2) significantly lower for 360 dicots (2.20 pg) than for 179 monocots (7.80 pg);(3) significantly lower for annuals (2.78 pg) than for perennials(6.65 pg);(4) significantly lower for 134 weed species (1.93 pg) than for herbaceous non-weeds (6.75 pg) and for several families that have an unusually high proportion of weed species;(5) significantly lower for 47 exotic weed species (1.76 pg) than for 134 native weeds (1.93 pg), but significantly lower than that of "non-weedy" herbaceous species (6.75 pg);(6) lower for weeds than for "non-weedy" species in same genus or family; and (7) in herbaceous species, generally lower for weedy compared to "non-weedy" species, with some exceptions such as Avena fatua, whose DNA C-value is as high as 14.15 pg, contrarily, and some "non-weedy" herbaceous species in Cruciferae and Cucurbitaceae with very low values.

统计了中国境内有分布的539种被子植物的DNA C-值，分析了它们在不同分类群、生活型、倍性、生活史类型以及在杂草和非杂草类群中的分布情况，主要结果如下：(1)539种被子植物DNA C-值平均为4.06 pg，其中木本植物的DNA C-值平均为1.84 pg，低于草本植物的平均值(5.02 pg)；(2)双子叶植物(360种)的DNA C-值平均为2.20 pg，极明显地小于单子叶植物(179种)的平均值(7.80 pg)；(3)1年生植物的DNA C-值平均为2.78 pg，明显小于多年植物的平均DNA C-值(6.65 pg)；(4)134种杂草的DNA C-值平均为1.93 pg，明显小于非杂草草本植物的平均值(6.75 pg)，含杂草较多的科，平均DNA C-值相对较小；(5)统计的47种入侵杂草的DNA C-值平均为1.76 pg，略小于134种杂草的平均DNA C-值(1.93 pg)，极显著地小于非杂草性草本植物(6.75 pg)；(6)以科为单位，不同科的DNA C-值存在着极大的差异；(7)DNA C-值与染色体倍性的关系并不明显，但是，随着倍性的增加，基因组变小；(8)在同一科、属中，与非杂草相比，典型杂草的DNA C-值往往偏小；(9)总体上杂草或杂草性强的植物，它们的DNA C-值比非杂草性植物的要小。

Salix matsudana, Ulmus pumila, Quermus mongolica, Populus alba×P.beroliensis and Betula platyphlla are frontal 5 tree species with weight value 90.37, 90.12, 88.12, 87.55 and 86.2 respectively, were used for farmland protection forest; Acer negundo, Salix matsudana, Juniperus rigida, Fraxinus mandshurica and Ulmus pumila are frontal 5 tree species with weight value 78.14, 76.92, 75.96, 74.72 and 74.56 respectively, were used for urban protection forest; Ulmus pumila, Salix matsudana, Populus alba×P.beroliensis, Acer negundo and Larix gemelinii are frontal 5 arbor tree species with weight value 80.07, 79.07, 77.5, 72.42 and 71.67 respectively, were used for road protection forest; Salix matsudana, Populus alba×P.beroliensis, Ulmus pumila, Larixgemelinii and Betula platyphlla are frontal 5 tree species with weight value 92.37, 88.72, 86.62, 85.82 and 85.7 respectively, were used for river protection forest; Fraxinus mandshurica, Larix gemelinii, Populus alba*P.beroliensis, Ulmus pumila and Salix matsudana are frontal 5 tree species with weight value 89.61, 8.35, 87.12, 85.56 and 80.15 respectively, were used for wood forest; Cornus alba, Prunus tomentosa, Primus triloba, Syringa obalata and Sambucus williamsii are frontal 5 shrubs with weight value 82.93, 81.23, 80.85, 78.38 and 77.78 respectively, were used for landscape forest; and Acer negundo,Malus baccata, Sorbus pohuashanensis, Prunus maackii and Prunus padus are frontal 5 arbors with weight value 82, 81.52, 80.3, 79.62 and 78.9 respectively, were used for landscape forest; Prunus salicina, Prunu

根据哈尔滨地区不同林种的功能要求，给出了不同指标的期望值，通过查询系统可以得到旱柳、榆树、蒙古栎、银中杨、白桦为符合农田防护林的前五位的树种，权重值分别为90.37、90.12、88.12、87.55、86.2；糖槭、旱柳、杜松、水曲柳、榆树为符合城市防护林的前五位的树种，权重值分别为78.14、76.92、75.96、74.72、74.56；榆树、早柳、银中杨、糖槭、兴安落叶松为符合道路防护林的前五位的乔木树种，权重值分别为80.07、79.07、77.5、72.42、71.67；旱柳、银中杨、榆树、兴安落叶松、白桦为符合河岸防护林的前五位的树种，权重值分别为92.37、88.72、86.62、85.82、85.7：水曲柳、兴安落叶松、银中杨、榆树、旱柳为符合用材林的前五位的树种，权重值分别为89.61、88.35、87.12、85.56、80.15；红瑞木、毛樱桃、榆叶梅、紫丁香、接骨木为符合风景林前五位的灌木树种，权重值分别为82.93、81.23、80.85、78.38、77.78，糖槭、山丁子、花楸、山桃稠李、稠李为符合风景林前五位的乔木树种，权重值分别为82、81.52、80.3、79.62、78.9；李、杏、文冠果、山楂、野梨为符合经济林的前五位的树种，权重值分别为88.85、80.88、73.25、69.35、63.77。

Results The sensitivity,specificity,positive predictive value,negative predictive value,Youden index,accuracy ...

结果检测血清特异性IgG的灵敏度为100·0%，特异度为97·7%，阳性预测值为97·2%，阴性预测值为100·0%，约登指数为0·977，符合率为98·7%，试验的一致率为98·5%；检测血清中总的特异性Ig灵敏度为97·1%，特异度为95·3%，阳性预测值为94·4%，阴性预测值为97·6%，约登指数为0·925，符合率为96·2%，试验的一致率为97·8%；检测唾液中特异性sIgA的灵敏度为96·2%，特异度为94·5%，阳性预测值为89·3%，阴性预测值为98·1%，约登指数为0·907，符合率为95·1%，试验的一致率为97·5%；检测粪便标本中的特异性sIgA的灵敏度为92·0%，特异度为90·2%，阳性预测值为85·2%，阴性预测值为94·9%，约登指数为0·822，符合率为90·9%，试验的一致率为98·6%，CV值均小于15%。

By synthetically analyzing the variation characteristics of pre-earthquake anomaly before five moderate-strong earthquakes in East China since 1990,discussing the pre-earthquake anomalous shape of b value and so on we obtained the comprehensive criteria for medium and short-term earthquake anomaly before moderately strong earthquake in East China:high YH value anomaly—low b value anomaly—low C and YH value anomaly—low Ds and Dt and Σ value anomaly and high b value anomaly—earthquake.

通过对华东地区1990年以来5次中强以上地震震前异常变化的综合分析，探讨了b值，Ds，Dt，C值， YH值，Σ值震前异常形态，并归纳出华东地区中强地震发生前测震学中短期异常的综合判据：YH值高值异常(主要出现在震前3年前后)—b值低值异常(平均出现在震前2年前后)—C、YH值低值异常(大体出现在震前1～2年前后)—Ds，Dt值低值异常、Σ值低值异常、b值高值异常(主要出现在震前1年内或稍长)—发震的模式。

This paper introduces the proof and application of Cauchy mean-value theorem from many angles in every aspect.

本文介绍了柯西中值定理的多种证明方法及其应用。

In the space, along with increased distance from the main ore-controlling structures, the frequency of P type of pyrite and their thermoelectricity also decreased gradually. Within one lode, from the upper to the lower parts of an ore body, the vertical change of pyrite in thermoelectricity as the follows:① when the ore body is stable, that is when the ore body is uniformly and continuously mineralized, the Dp andαvalues keep increased from shallow to deeper parts;② when an ore body is discontinuously mineralized, the Dp andαvalues have a wavy increasing tendency from the shallow to the deeper;③ when the deeper part of an ore body contains abundant, Co and Ni high mafic dykes, the Dp andαvalues of pyrite decreased from the shallow to the deeper parts of an ore body, that is, an reversed zoning of pyrite thermoelectricity occurs for pyrite in this situation contain more Ni and Co and belongs to N type.④ For the deposits hosted in the Archean metamorphic rocks, because all of the pyrite in this case is N-type, the vertical change of pyrite is not featured by the transition of pyrite type, but by the increased values of Vnp and α from the shallow to deeper parts of an ore body.

在空间域上，水平分带规律为：随远离主干断裂，矿脉中P型的出现频率逐渐降低或热电系数值逐渐变小；在同一条矿脉中，这是由于矿化不均匀性及脉岩的影响，由矿体的上部到下部，它的垂向变化特征可以有如下几种变化形式：①由矿体的浅部到深部，黄铁矿的Dp值、或α值呈稳定升高的趋势时，矿体往往表现为矿化均匀，连续性好、延伸稳定；②由浅部到深部，黄铁矿的Dp值、α值呈波状变化，但总体又具有增大的趋势时，所在的矿体连续性差；③当矿脉的下部发育有大量的基性脉岩时，由于基性脉岩中常含有较高的Co、Ni，使其中黄铁矿的Co、Ni含量较高而呈N型导电，由矿体的上部到下部，黄铁矿的Dp值、α值呈减少的趋势，而造成黄铁矿热电性特征的逆向分带，④产于太古代变质岩中的中深脉状金矿，由于其中的黄铁矿均为N型导电，所以垂向变化规律并不表现为导型的改变，只是Vnp值或α值从矿体的上部到下部由小变大。

Because the proposed method integrates the advantages of the median-filter and PDE methods, it can restrain the salt-and-pepper noise for the noise density range from 10% to 95%, and at the same time effectively repair the edge and detail information in videos. Moreover proposes some speed-up design and optimization strategy which promotes the efficiency significantly.

研究高强度椒盐噪声的抑制算法，提出了逐次修复和邻域修复的概念，结合了中值滤波和PDE两类算法的优势，能够在抑制高强度椒盐噪声的同时，较好的修复图像的细节和边界信息。

Measures of central tendency include mean, median, and mode.

集中趋势的测量包括均值、中值和众数。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。