一般回归模型中的U统计量

本文考虑一般回归模型中回归系数的方向的估计问题。一般回归模型的定义中,应变量y在自变量x给定之下的分布只依赖于x之分量的线性组合。这个线性组合的系数向量β就是回归系数向量。一般回归模型是通常线性模型的推广。本文中,我们构造了一个U统计量作为β之方向的估计。在适当的光滑性条件下,本文证明了该U统计量作为β的方向的估计具有相合性与渐近正态性。     

A New Method for the Analysis of Relative Permeability in Porous Media

By combining three-dimensional digital microtomography techniques with the lattice Boltzmann method,a new methodology is used to analyse the relative permeability of multiphase flow in porous media.The results indicate that the two coupling coefficients K12 and K21 have the same magnitude,therefore the Onsager reciprocity still holds,the results also agree well with the results of pipe flow numerical experiments.     

空气/水界面水分子的取向和运动

对四种不同的实验构型下空气／水界面自由O-H键在3700cm~(-1)的和频振动光谱的分析表明,水分子在空气／水界面的取向运动只可能是在平衡位置附近有限角度之内的受限转动。界面水分子的自由O-H键取向距界面法线约33°,而取向分布或运动的宽度不超过15°。这一图像显著地不同于Wei等人(Phys. Rev. Lett.86,4799(2001))只通过单一的SFG实验构型所得出结论,即：空气／水界面的水分子在超快的振动弛豫时间内在很大的角度范围内运动。     

A waveguide polarizer based on Si-coated Ti:LiNbO_3 planar structure

A novel design of a transverse magnetic (TM)-pass waveguide polarizer based on Si on an X-cut, Y-propagatiou Ti:LiNbO3 planar waveguide is presented. The eigenvalue functions of such structure have been obtained by using Wenzel-Kramers-Brillouin (WKB) method with modified Airy functions. The intervals of the silicon thickness have been found which result in transverse electric (TE) light suffering strong attenuation while TM wave propagating with fairly low loss. A planar waveguide polarizer is fabricated and its polarization-dependent measurements lead to the best polarization extinction ratio ~ 34 dB and the insertion loss < 0.4 dB.     

Fabrication of Dendrimer－like PAMAM Based on Silica Nanoparticles

A G 4.0 dendrimer-like poly (amido amine) (PAMAM) based on silica nanoparticles was fabricated via a divergent approach.It was built from γ-aminopropyi silica nanoparfides (APSN) core via repetitive addition of acrylate (MA) and hexylenediamine (HDA). FT-IR and EA were used to monitor the progress of dendrimer during each step. The amino group content of the resulting product increased from 0.49 to 3.72 mmol/g after the 4th generation. In addition, the percentage of grafting increased with increasing generation and reached to 65.9% after 4th generation. It was found that the resulting silica nanoparticles could be dispersed in methanol with a mean hydrodynamic particle diameter of 152.7 nm although the silica nanoparticles had agglomerated during the storage period.     

BIN PACKING中γm≤1.20的直接证明

ＢＩＮＰＡＣＫＩＮＧ中γ_ｍ≤１．２０的直接证明刘明堂，越民义（中国科学院应用数学研究所，北京１０００８０）ＡＤＩＲＥＣＴＰＲＯＯＦＯＦＴＨＥＩＮＥＱＵＡＬＩＴＹγ_ｍ≤１．２０ＩＮＭＵＬＴＩＰＲＯＣＥＳＳＯＲＳＣＨＥＤＵＬＩＮＧ￥ＬＩＵＭＩＮＧＴＡＮ...     

An Estimation for the Power-Law Distribution Parameter Based on Entropy

A new estimation based on the Shannon entropy for the power-law distribution parameter is presented, The maximum likelihood estimation （MLE） of the parameter is discussed and the relation between the MLE and the moment estimation of the parameter is given out. It is shown that the minimum Shannon entropy estimation is equivalent to the MLE giving the log expectation.     

尿样中核基质蛋白22的免疫电化学生物传感器研制

将(4,4',4',4')四羧基酞菁钴(CoTcPc)和HRP标记核基质蛋白22抗体(HRP-Ab-NMP22)一起固定在Au电极表面,构建了一种快速测定膀胱肿瘤患者尿液中NMP22抗原含量的安培免疫传感器(HRP-Ab-NMP22/Fe3O4/CoPc CME).实验表明:该传感器对NMP22抗原具有良好的电化学响应,HRP对H2O2电催化氧化电流I0降低,△I0与NMP22浓度在1.0～150ng·mL-1成线性关系,检测限则为0.5ng·mL-1.该传感器基于一次性竞争性免疫反应,较Elisa法提高了检测速度,有望用于膀胱肿瘤的迅速诊断.     

绝缘层上半导体多晶膜激光再结晶临界条件

从理论的角度分析了绝缘衬底对其上面半导体多晶膜激光熔化再结晶过程的影响, 发现低导热的绝缘层使产生固一液相变的临界激光功率有明显的降低.用喇曼光谱测量了激光再结晶SOI层中的应力. 应力的出现是多晶膜内曾经发生过固一液相的佐证.从这一思想出发, 对LPCVD方法制备的大量SOI 样品进行激光再结晶临界条件的研究, 证明了忽略绝缘层低热导影响的模型不能解释实验结果, 而经过修正的公式则可以较好地拟合实验结果, 关键词：     

手分为多节段的人体热调节模型研究

将人体热调节柱状模型和手的多节段模型结合起来,建立了更完整的人体热调节模型。利用有限元方法对人体热调节数学模型进行了数值求解,并设计试验证明了模型的正确性。结果表明: (1)当取合适的血流量时,实验值和计算值的变化趋势一致,且手部温度稳定时,血流量都在确定的范围内;(2)血液流量是手部温度场变化的主要因素,人体组织和动脉入口温度对手部温度影响较小。