解干扰力下平板动力响应的DQ半解析法

本文针对干扰力Ｆ（Ｔ，ｔ）－Ｑｓｉｎωｔ作用下圆形薄板的动力响应问题，提出了ＤＱ半解析法。该方法直接从控制秃分方程出发，在空间域采用ＤＱ法（Ｄｉｆｆｅｒｅｎｔｉａｌ Ｑｕａｄｒａｔｕｒｅ Ｍｅｔｈｏｄ），在时间域取级数，采用时域配点法得到求解位移场全部待定参数的线性方程组。解一次线性方程组即全域的动力响应位移场。     

Multiple-State Storage Capability of Stacked Chalcogenide Films （Si16Sb33Te51/Si4Sb45Te51/Si11Sb39Te50） for Phase Change Memory

The multiple-state storage capability of phase change memory （PCM） is confirmed by using stacked chalcogenide films as the storage medium. The current-voltage characteristics and the resistance-current characteristics of the PCM clearly indicate that four states can be stored in this stacked film structure. Qualitative analysis indicates that the multiple-state storage capability of this stacked film structure is due to successive crystallizations in different Si-Sb-Te layers triggered by different amplitude currents.     

Experimental Studies on Thermal and Electrical Properties of Platinum Nanofilms

We experimentally studied the in-plane thermal and electrical properties of a suspended platinum nanofilm in thickness of 15 nm. The measured results show that the in-plane thermal conductivity, the electrical conductivity and the resistance-temperature coefficient of the studied nanofilm are much less than those of the bulk material, while the Lorenz number is greater than the bulk value. Comparing with the results reported previously for the platinum nanofilm in thickness of 28 nm, we further find that the in-plane thermal conductivity, the electrical conductivity and the resistance-temperature coefficient decrease with the decreasing thickness of the nanotilm, while the Lorenz number increases with the decreasing thickness of the nanofilm. These results indicate that strong size effects exist on the in-plane thermal and electrical properties of platinum nanofilms.     

对称正则长波方程的一个守恒差分格式

本文考虑了具有齐次边界条件的对称正则长波方程的有限差分法．构造了一个两层守恒的有限差分格式,利用离散泛函分析方法分析了格式的收敛性和稳定性,从理论上得到了收敛阶为O(h~2 τ)．数值试验表明,我们的方法是可信的．     

多子阵子空间拟合波达方向估计

提出了考虑阵元互耦的子空间拟合波达方向估计方法。用一带状、对称Toeplitz矩阵对均匀线阵的互耦矩阵建模。根据互耦矩阵自由度,去除部分两边阵元,研究了子空间拟合算法中ESPRIT算法的理论性能。在大快拍的情况下,均匀线阵的MCLS-ESPRIT算法的角度估计误差是一个零均值的联合高斯分布,同时给出了分布的协方差表达式。由方差的数值计算可知,在阵元数和信源数确定的情况下,存在估计标准差最小的子阵;与不存在互耦的理想情况相比,除了估计标准差少许增加外,性能接近。本文的方法已应用于高分辨率测深侧扫声呐,获得了好结果。在声呐阵阵元数增加的条件下,用本文的方法,能抑制均匀线阵的互耦的影响。     

PROFILE MINIMIZATION PROBLEM FOR MATRICES AND GRAPHS

ＰＲＯＦＩＬＥＭＩＮＩＭＩＺＡＴＩＯＮＰＲＯＢＬＥＭＦＯＲＭＡＴＲＩＣＥＳＡＮＤＧＲＡＰＨＳＬＩＮＹＩＸＵＮ（林詒勋）；ＹＵＡＮＪＩＮＪＩＡＮＧ（原晋江）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＺｈｅｎｇｚｈｏｕＵｎｉｖｅｒｓｉｔｙ，Ｚｈｅ...     

BBO晶体拉曼光谱的高温特性研究

ＢＢＯ晶体拉曼光谱的高温特性研究李郁陈凯旋尤静林蒋国昌（上海大学上海２０１８００）洪慧聪路治平仲维卓（中科院上海硅酸盐研究所上海２０００５０）ＨｉｇｈＴｅｍｐｅｒａｔｕｒｅＲａｍａｎＳｔｕｄｙｏｆＢＢＯＣｒｙｓｔａｌＬｉＹｕ，ＣｈｅｎＫａｉｘｕａｎ...     

LIE ALGEBRA K(n,μj,m)OF CARTAN TYPE OF CHARACTERISTIC p=2.

Let K(n,μ_j,m),n=2r+1,denote the Lie algebra of characteristic p=2,which isdefined in [4].In the paper the restrietability of K(n,μ_j,m)is discussed and it is provedthat,when r≡1(mod 2)and r>1,1(ad.f)=n+1 if and only if 0≠f∈.Then theinvariance of some filtrations of K(n,μ_j,m)and the condition of isomorphism of K(n,μ_j,m)and K(n′,μ_j′,m′)are obtained.Besides,the generators and the derivation algebraof K(n,μ_l,m)are discussed.The results also hold,when r=0(mod 2)and r>0.