正交性原理及其在维纳滤波中的应用

证明了L2空间中的正交性原理，得到正交性原理与线性最小均方误差估计与维纳滤波是等价的结论，并用正交性原理推导出连续型的维纳—霉夫方程及误差表达式。     

带衰退记忆的经典反应扩散方程的强全局吸引子*

当任意阶多项式增长的非线性项为耗散, 且外力项仅属于$L^2(\Omega)$时, 研究了带衰退记忆的经典反应扩散方程的解在强拓扑空间$H_0^1(\Omega)$$\times L_\mu^2(\mathbb R^+; D(A))$的长时间行为. 应用抽象函数理论、半群理论以及 新的估计技巧, 在拓扑空间$H_0^1(\Omega)\times L_\mu^2(\mathbb R^+; D(A))$上, 验证了强解半群的渐近紧性并且证明了强全局吸引子的存在性.     

实现CRC算法的三种工程方法

主要介绍几种实现CRC的工程算法——按比特实现法、块异或汇编实现法、查余式表实现法,并通过在zsp400的内核环境下运行和仿真这几种实现法,从而得出结论:查余式表实现法是一种较好的实现法。     

Enhancement of tribological properties in siliconized graphite via hierarchically hybrid SiC/C composite

This study aims to investigate tribological properties in a siliconized graphite(СГ-П-0.5) and hierarchically hybrid Si C/C composites at the load ranging from 10-40 N under dry air/water lubrication conditions. A feasible liquid silicon infiltration(LSI) was used to fabricate the Si C/C composites. Morphology and phase identification of two materials were characterized and analyzed by scanning electron microscope(SEM) and energy dispersive spectrometer(EDS). An image feature extraction was used to post-process the data of wear test, further to gain the wear properties of the samples. The results demonstrated that a lower coefficient of friction(COF) and wear rate can be achieved in the LSI Si C composites than that in the sample of СГ-П-0.5. Both COF decreased under waterlubricated conditions, compared with that under the dry air lubrication. The excellent tribological properties in two materials can be due mainly to the microstructure of the СГ-П-0.5 sample, showing much more graphite and Si dispersed on the matrix. The СГ-П-0.5 sample indicated the typical oxidative wear mechanism, whereas, the sample of LSI Si C demonstrated the combined oxidative and fatigue wear. This finding can provide a promising new siliconized graphite materials for ceramic rolling bearings.     

Optimal Replenishment Problem for Items with Polynomial Demand During Their Life Period

1.INTANDUCTIONThetraditionaleconomicorderquantity(EOQ)modelswereformulatedinastaticenvironmentwhereademandtobeconstantandinflexible.Inthelasttwodecades,considerableattentionshavebeengiventoEOQmodelswithtime-varyingdemand,suchasthereferences[2-7].Viewedfromthedemandpattern,thesemodelsmaybeclassifiedastwosorts.Onesortisonlyusableforincreasingdemand.Theotherisfitfordecreasingdemand.However,inarealisticproductlifecycle,thedemandisincreasingwithtimeduringtheinitialstageofthelifecycle.Afterr…     

3S技术在我国草地和农业生态系统中的应用进展

The grassland yield was an important index to estimate the prataeultural productivity, and it was also the basis to plan the productions of animal husbandry. It had an important meaning whether the dynamic grassland information in large areas could be timely grasped in order to     

Logistic模型的参数估计及其实证研究分析

本文首先对Logistic模型的理论基础和性质进行了推导和研究,然后利用极大似然估计法对模型的参数进行了估计,另外对Logistic模型在实证研究中存在的问题进行了分析和评估。     

无失效数据失效率的综合E-Bayes估计

对指数分布场合无失效数据的失效率进行估计.在先验分布为Gamma分布时,通过两种方式引进失效信息并在这两种方式下给出了失效率的综合E-Bayes估计,然后得出了产品可靠度的综合估计.     

河北沽源草地生态系统服务功能价值分析

利用遥感技术,采用改进的光能利用率模型反演植被净第一性生产力,并结合草地生态系统服务功能量化指标,利用碳税法、替代费用法等对河北省沽源县的草地生态服务功能具体指标价值进行测算。结果发现:研究区域草地生态系统服务功能总价值为63 500.57万元,其中,涵养水源价值较高,为36 304.84万元,占总价值的57.17%;其次为生产有机物,占21.75%;O₂释放量为10.79%;CO₂固定量为9.54%;营养物循环为0.75%。就各草地类型服务功能而言,温性草甸草原类生态系统服务价值在各项服务价值中均较高,合计达29 008.44万元,占总价值的45.68%。     

Poisson型密数在多项式加权空间的逼近特征

利用Ｐｏｌｙａ基函数构造一类Ｐｏｉｓｓｏｎ型密度函数，并研究Ｐｏｉｓｓｏｎ型密度函数在多项式加权空间的逼近特征．