良好状态

This model can provide the good base of adaptive modulation and coding and automatic repeat request as well as dynamic resource allocation.

首先分析了正交频分复用技术频域信道统计特性，说明了Nakagami-m分布能更好地描述衰落信道；然后针对高速移动及OFDM信号传输的特点，采用状态持续时间相等法建立了OFDM频域信道有限状态马尔可夫模型，分别给出了计算持续时间、状态门限及状态数、转移概率、状态差错率的一般方法及m=0.5\1\2典型值的闭式解，该模型能为自适应模型控制、混合自动重传请求 HARQ、动态资源分配等技术提供良好的基础。

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 security of PKI system itself is especially emphasized during the system design and implementation process, which is in accordance with the pervasive characteristic of PKI. Second, the concept of a Trusted Key Management Center is introduced for the first time. This technology greatly strengthens key management practices and allows for smooth transition from PKI to Key Management Infrastructure. Third, certificate status mechanisms are investigated in depth, and a certificate revocation performance simulation system is devised. All these work will provide guides to practice and employment of PKI applications. Based on time constraints, a new taxonomy for authenticated dictionaries is proposed. Fourth, formal analysis ofOCSP protocol is carried out; then an efficient and scalable OCSP system is developed. Fifth, the special requirements caused by the working environments of Wireless PKI are analyzed. Based on communicative hashing and dynamic Merkle hash tree, an efficient certificate status validation method suitable for WPKI is presented. Sixth, one important kind of fair exchange protocols is studied, and a new CEMBS based on RSA cryptosystem is proposed. Afterwards, a novel fair exchange protocol totally based on RSA signature scheme is devised.

在系统设计和实现的过程中，考虑到PKI作为普适性安全基础平台的特点，特别强调PKI系统自身的安全性；第二，首次在PKI系统的设计中提出了"可信密钥管理中心"的概念，这一独特设计大大地强化了密钥管理功能的实施，为PKI向密钥管理基础设施的平滑过渡提供了良好的技术准备；第三，对证书状态验证机制进行了深入研究，设计了证书状态模拟系统，以指导PKI系统和应用的部署和实施；在此基础上，基于时间约束首次给出了认证字典的一种新的分类方法；第四，对OCSP协议进行了形式化分析，设计和实现了一种高效、可扩展的OCSP系统；第五，分析了WPKI工作环境对设计安全基础平台提出的特殊要求，结合无线移动设备的具体特点，基于可交换杂凑函数和动态Merkle杂凑树设计出了一种适用于WPKI环境的高效证书状态查询机制；第六，对一类公平交换协议进行了深入的研究，从设计公平交换协议的密码基础结构出发，提出了一种新型的基于RSA密码体制的高效CEMBS；在此工作的基础上，设计了一种基于RSA密码体制的最优化公平交换协议。

The security of PKI system itself is especially emphasized during the system design and implementation process, which is in accordance with the pervasive characteristic of PKI. Second, the concept of a Trusted Key Management Center is introduced for the first time. This technology greatly strengthens key management practices and allows for smooth transition from PKI to Key Management Infrastructure . Third, certificate status mechanisms are investigated in depth, and a certificate revocation performance simulation system is devised. All these work will provide guides to practice and employment of PKI applications. Based on time constraints, a new taxonomy for authenticated dictionaries is proposed. Fourth, formal analysis of OCSP protocol is carried out; then an efficient and scalable OCSP system is developed. Fifth, the special requirements caused by the working environments of Wireless PKI are analyzed. Based on communicative hashing and dynamic Merkle hash tree, an efficient certificate status validation method suitable for WPKI is presented. Sixth, one important kind of fair exchange protocols is studied, and a new CEMBS based on RSA cryptosystem is proposed. Afterwards, a novel fair exchange protocol totally based on RSA signature scheme is devised.

在系统设计和实现的过程中，考虑到PKI作为普适性安全基础平台的特点，特别强调PKI系统自身的安全性；第二，首次在PKI系统的设计中提出了"可信密钥管理中心"的概念，这一独特设计大大地强化了密钥管理功能的实施，为PKI向密钥管理基础设施的平滑过渡提供了良好的技术准备；第三，对证书状态验证机制进行了深入研究，设计了证书状态模拟系统，以指导PKI系统和应用的部署和实施；在此基础上，基于时间约束首次给出了认证字典的一种新的分类方法；第四，对OCSP协议进行了形式化分析，设计和实现了一种高效、可扩展的OCSP系统；第五，分析了WPKI工作环境对设计安全基础平台提出的特殊要求，结合无线移动设备的具体特点，基于可交换杂凑函数和动态Merkle杂凑树设计出了一种适用于WPKI环境的高效证书状态查询机制；第六，对一类公平交换协议进行了深入的研究，从设计公平交换协议的密码基础结构出发，提出了一种新型的基于RSA密码体制的高效CEMBS；在此工作的基础上，设计了一种基于RSA密码体制的最优化公平交换协议。

Through correlative analysis and path analysis, it finds that (1) the family environment and the colleges and universities environment have direct and indirect influence on self-identity development of students; and (2) the family environment and the colleges and universities environment exert the major effect on self-identity development of students through identity style as mediational variable, so identity style becomes the explanatory base of self-identity status. That is, the predictive effect of diffuse/avoidant identity style for identity diffusion, normative identity style for identity foreclosure, and information identity style for identity achievement respectively is most significant; and (3) family environment that is helpful, supportive, warm, expressive, and promote autonomy and independence possibly makes students form identity achievement or identity moratorium, family environment that is excessively cohesive and warm but lacking independence possibly promote students to form identity foreclosure, and family environment that lacks of supportive and warm possibly make students form identity diffusion; and (4) colleges and universities environments that have better relationship system, clear developmental purpose, and promote to pay attention to societal concerns, critical and explorative qualities, and provide healthy, expressive, democratic, open atmosphere facilitate identity development, in turn form advanced identity. Colleges and universities environments that only emphasize the receival of colleges and universities aims, order and instilments, and scarcely encourage critique, exploration, individuation possibly make students form identity foreclosure. However, the ones that is remote relationship system, and lacking support, and students don't cognize the aim of colleges and universities possibly make students form identity diffusion.

通过相关分析、路径分析发现：(1)家庭环境和学校环境对大学生自我同一性有直接和间接的影响；(2)家庭环境、学校环境对大学生自我同一性影响主要以同一性加工方式为中介变量，同一性加工方式成为自我同一性状态的解释基础，弥散—回避定向同一性风格对弥散型同一性预测力最大，信息定向同一性风格对成就型和延缓型同一性预测力最大，常规定向同一性风格对排他型同一性预测力最大；(3)相互支持、帮助、关心、自由表达和鼓励自主和独立的家庭环境促进大学生同一性的发展，形成成就型或延缓型同一性状态，过度亲密而缺乏独立性特征的家庭环境可能形成排他型同一性状态，而缺乏支持性，关系疏远的家庭环境可能形成弥散同一性状态；(4)良好的关系系统，明确的发展目标，鼓励学生对社会事务关注、倡导批判和探索精神，塑造良好、健康、可供自由表达、民主、开放的文化氛围的大学校园环境促进大学生同一性发展，形成高级、成熟的自我同一性，而一味强调学校目标的接受，强调秩序、灌输，缺乏对批判、探索、个性发展鼓励的学校环境有可能使学生形成排他型同一性状态，但若学校的关系系统疏远，缺乏支持性的民主的风格，目标不能被学生明确感知的学校环境则可能影响学生形成弥散型同一性。

If you've been both sleep-deprived and well-rested, it probably isn't a big surprise that consistent, good sleep beefs up your physiological ability to cope with stress.

如果你曾经有过睡眠剥夺状态也有过良好休息状态，那么就不会奇怪大概持续良好的睡眠会增强对付压力的生理能力。

In the vocal art education process, the teachershould pay attention to adjustingthe student's psychological diathesis.

具有良好的歌唱心理状态，对每个声乐学习者和歌唱者而言都很重要，良好的心理状态能够增强学习与表演者成功的信心。

Humans were once cognoscente of how to focus the energy flow for the maintenance of one's health and well being.(See " Synthesis Meditation " and " Elements Meditation " for more information.) The Grand Master humans with the large heads in particular that were seeded upon earth some 50,000 years ago from Sirius (200,000 human years) understood the energetic dynamics of their own fields.

人类曾经对如何聚焦能量流以维系健康与良好状态的过程很在行（更多信息请看合成冥想和元素冥想）。5万年（20万人类年）前从天狼星播种到地球上的大头颅人类大师，尤其懂得他们自身能量场的机制。

Wherever the form is not crystalline, such cells fail to do their fair share or job to sustain the overall well-being of the form.

不管哪里的身体不是晶态，这些细胞就无法做它们被分配的那份工作来维系身体整体的良好状态。

The change was due to the players' will to be protagonists on the pitch this year as well.

球员们在场上争相表现(才是球队有了这样的良好状态)。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。