下界的
- 与 下界的 相关的网络例句 [注:此内容来源于网络,仅供参考]
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In the fourth chapter, firstly it introduces the Boolean functions algebraic expressions of the 2-value clock-controlled stop-and-go generator and Gunther generator. It reveals the balanced property of the two kinds of Boolean functions, and studies the Walsh cycle spectrum and the autocorrelation function. It also obtains the coincidence rate of their output sequences with affine sum of some bits of input sequences, and analyzes their ability of resisting the best affine approximation cryptanalysis and differential cryptanalysis. Secondly, we properly present a new definition of the Best Affine Approximation, namely BAA on the Boolean vector functions, followed by the spectral characteristic of such defined BAA attacks through using the decomposition formula of the union distribution for random variables. A lower bound of such BAA attacks is proposed. Finally, we also study the spectral characteristic of the second kind of nonlinearity of Boolean vector functions, followed by a higher bound of such nonlinearity. Furthermore, the limited relationship between the second kind of nonlinearity of Boolean vector functions and the linear structure of the linear combination of every component is analyzed.
在第四章中,首先给出了2值密钥流"停走生成器"和"衮特生成器"中实际存在的布尔函数的代数表示,揭示了这两类布尔函数的平衡性,随后研究了它们的Walsh循环谱和自相关函数等,得到了它们的输出序列与输入序列中的某些bit的仿射项的符合率,分析了它们抵抗最佳仿射逼近攻击和差分攻击的能力;其次,我们合理地给出了布尔向量函数最佳仿射逼近的新定义,利用布尔随机变量联合分布的分解式考察了相应的谱特征,并给出了布尔向量函数与其最佳仿射逼近的符合率的一个下界;最后,我们还考察了布尔向量函数第二类非线性度的谱特征,给出了布尔向量函数第二类非线性度的一个上界,并揭示了布尔向量函数第二类非线性度与其各个分量的线性和的线性结构之间存在的制约关系。
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The proposed method has the merit that the numerical characteristics of stochastic temperature field response can be obtained by analyzing the random temperature field just in one time.3. Perturbed numerical algorithm of nonprobabilistic convex set theoretical models on the temperature fieldThe uncertain parameters of physical parameters and initial boundary conditions of heat conduction are described by the convex model. The perturbation formulas of the upper and lower bounds of temperature field response with unknown-but-bounded parameters are given via the combination of matrix perturbation theory and the convex set theory model.4. Numerical analysis for transient temperature field with interval parametersConsidering the uncertainties of the transient heat transfer, the physical parameters and initial boundary conditions are regarded as interval variables.
该方法具有只进行一次随机温度场分析便可以获得其响应的数字特征的优点。3、温度场的非概率凸集合理论模型的摄动数值解法将结构导热的物理参数、温度场的初始和边界条件等不确定性参数以凸模型加以描述,基于矩阵摄动理论和处理不确定问题的凸集合理论模型的结合,导出有界不确定参数瞬态温度场响应所在集合的上、下界摄动计算公式。4、具有区间参数的瞬态温度场数值分析考虑结构瞬态热传导问题的不确定性,将结构各物理参数和温度的初、边值条件均视为区间变量。
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If all the flows getting into the system were constrained by the leaky-bucket parameters, the maximum cell delay and the buffer content bound were got when the capacity of the crosspoint was enough, and the maximum cell delay and the buffer capacity bound which can guarantee the maximum cell delay were also got when the content of the crosspoint was not enough.
在各数据流都由令牌桶参数约束的条件下,得到了交叉点缓存容量足够大情况下的最大信元时延和缓存临界容量大小,还得到了交叉点缓存容量不足够大情况下的最大信元时延以及保证信元具有时延上界的缓存临界容量大小。
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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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In chapter four,we give the proof of some results about the lower bound for the first eigenvalues with non-boundary condition.
第四章给出了不带边情形下的一些第一特征值下界估计的证明。
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The right subcostal margin corresponds to the lower limit of the liver, while the right nipple is about half an inch above the upper limit of this viscus.
右肋骨下缘是肝的下界,右乳头在这个器官的半寸上方。
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In this paper,the problem of the rate of uniform convergence in the normal approximations of the Von Mises Statistics will be considered.
本文讨论了Von Mises统计量向正态逼近的一致收敛速度问题,在核函数仅满足二阶矩条件下,给出了上述收敛速度的上、下界,所得结果改进了 [2 ]中相应结论
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This dissertation was focused on the research about the formation and evolution of NQB from the Late Triassic to the early middle Epoch of Jurassic Period, including integrated analyzing the characteristic of the key stratigraphic surfaces, the time of the key stratigraphy, regional rock straigraphy, biostratigraphy and chronostratigraphy, sedimentary system and depositional facies. On basis of these analysis, a tectonic evolution model have been established for NQB during from the Late Triassic to the early middle Epoch of Jurassic Period.1. After the systematic surface analysis about main stratigraphy units, we found that:(1) the bottom of Xiaochaka formation was comformity with the middle Triassic in the basin, and in the north margin it was deposited and overlapped on the different period stratigraphy before Triassic.(2) The top surface of Xiaochaka formation developed regionally karst and paleo-karst breccia, and was uncomformity with Nadigangri Formation, these things suggest that NQB in Xiaochaka depositing stage was developed from middle Triassic basin, and then an extensive regression occurred, the deposition was over and erosion come into being.(3) The lithologic assemblage, geochemistry, mixed fossils, and stratigraphy overlapping characteristic of Quemocuo Formation in early middle Jurassic indicted that the uncomformity surface was an extension-unconformity.2. Integrated analysis about stratigraphy division and correlation indicted that:(1) the paleontologic assemblage of Xiaochaka formation show its time was Carian -Norian stage of late Triassic. According to it was overlapped by late Triassic Nadigangri Formation, so Xiaochaka formation should be Carian - early Norian stage.(2) the SHRIMP Zircon U-Pb age of Nadigangri formation volcanic rocks wear vary form 216 to 205 Ma, so its time should be Norian, but maybe extended into Rhaetian Stage.(3) The age of its bottom volcanic rocks, the fossil assemblages of its middle and upper members and overlapped by lower Jurassic, indicted the age of Riganpeicuo Formation was Norian - Rhaetian stage. And the same time, the volcanic rocks geochemistry of Nadigangri and Riganpeicuo formation both reflected that they wear formed in rift tectonic settings. The lower lithologic and surface characteristic, fossil assemblages and its upper maybe was conformity with lower Jurassic, all reflected that the age of Tumengela Formation in Tumen area should be Norian - Rhaetian stage.
论文对晚三叠世—中侏罗世早期盆地的形成与演化开展了研究,包括关键地层界面特征分析、关键地层时代归属分析、区域岩石地层、生物地层和年代地层的综合对比分析、区域沉积体系与沉积相分析、岩相古地理分析,最终建立晚三叠世—中侏罗世早期羌塘盆沉积—构造动力演化模式。1、系统的对各地层单元的界面分析发现:(1)肖茶卡组底界在盆地内部与中三叠统整合关系,在盆地北缘为沉积超覆于不同时代的前三叠系之上:(2)肖茶卡组顶界面发育古岩溶角砾岩,与上覆那底岗日组为岩溶不整合接触,说明肖茶卡组沉积时期的羌塘盆地是在早中三叠世的盆地基础发展起来的,后期出现了广泛的海退事件,使盆地结束沉积并遭受风化剥蚀作用;(3)中侏罗统雀莫错组的岩性组合特征、岩石化学特征、古生物化石混积和地层的沉积超覆现象均表现出裂陷环境下形成的伸展不整合面的特征。2、综合地层划分与对比分析认为:(1)肖茶卡组古生物化石组合反映其时代为晚三叠世卡尼期—若利期,根据其上被上三叠统那底岗日组不整合覆盖,将其时代厘定为卡尼期—若利期早期;(2)那底岗日组火山岩SHRIMP锆石U-Pb年龄在216~205 Ma之间,其时代主要为若利期,可能包含有瑞替期:(3)日干配错组底部火山岩的年龄、中上部化石组合及其被下侏罗统整合覆盖,综合反映的时代为晚三叠世若利期—瑞替期,而且那底岗日组火山岩和日干配错组火山岩的地球化学成分分析反映两者均为引张构造背景下的产物;土门地区的土门各拉组的下部岩性及界面特征、化石组合和上部可能被下侏罗统整合覆盖,综合反映其时代为若利期—若利期。
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For 2p〓-periodic binary sequences, a new weight function, according to the above presented vector expression of the linear complexity, is defined. By analyzing the weight of the product of a special kind polynomial in finite field, the upper and lower bounds on minimum error, expressed by the here denned weight of the linear complexity, are given in different cases.
对于2p〓-周期二元序列,利用所给出的线性复杂度的向量表示定义了一种新的重量函数,通过研究有限域上一类特殊多项式乘积的重量,分情况给出了用线性复杂度的重量表示的最小错误minerror的上界和下界,这里的重量是由我们所定义的重量函数确定的。
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The distances between inferior margin of 12th rib and the 3 above-mentioned nerves were all measured. Results: The superior lumbar triangle was quadrilateral (55%), triangular (35%) or irregular (5%). If the 12th rib was too short, the upper border of the triangle would be the 11th rib (5%). Four grouping patterns of the 3 nerves were found in front of the triangle, and the average distance between inferior margin of 12th rib and the 3 nerves was (16.92±6.32)mm,(59.49±14.97)mm and (112.49±17.15)mm, respectively.
结果:腰上三角的形态可为四边形(55%)、三角形(35%)和不规则形(10%),该三角的上界可完全由第11肋(5%)构成;肋下神经、髂腹下神经和髂腹股沟神在腰上三角前方有4种不同的组合形式,三神经与第12肋下缘的平均距离分别为(16.92±6.32)mm、(59.49±14.97)mm、(112.49±17.15)mm。
- 推荐网络例句
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Do you know, i need you to come back
你知道吗,我需要你回来
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Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.
1〕 杨银书,王祥生,李德昌。安徽省首次发现嗜群血蜱。
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Chapter Three: Type classification of DE structure in Sino-Tibetan languages.
第三章汉藏语&的&字结构的类型划分。