多芯片组件的互连与灵敏度分析

特性尺寸的减小、系统复杂性的增加和工作速度的提高已使互连成为影响电路性能的重要因素,因此如何快速而有效地进行互连分析是很重要的．在对传输线进行分析后发展了一种用ＡＷＥ对含耦合传输线的电路进行分析的方法．通过把矩阵指数函数展开可以方便地求出应用ＡＷＥ方法时需要求得的系数．该方法仅需进行矩阵的加法、乘法运算和一次ＬＵ分解,能快速而有效地求取含多根耦合传输线的互连网络的瞬态响应．在电路设计中灵敏度很有用,因为它是优化、统计分析、可靠性分析和面向性能设计的基础．将该方法推广应用于灵敏度分析得到了一种求取灵敏度的新方法．与传统的ＳＰＩＣＥ方法相比,该方法是高效的．     

可积函数的逼近性质的证明及其应用

考虑黎曼可积函数可用阶梯函数和连续函数逼近的问题,应用黎曼可积函数的充分必要条件定理,给出了可积函数的逼近结果的详细证明,并指出了这些逼近结果的一些应用,沟通了相关问题之间的联系和发展变化．     

The design of adaptive sigma-delta A/D converter

The signal to noise ratio （SNR） of conventional sigma delta analog to digital converter （∑△ADC） reduces with input signal strength. The existing concept of adaptive quantization is applied to the design of ∑△ADC to improve SNR with high dynamic range. An adaptive algorithm and its circuit implementation is proposed. Because of the error due to the circuit implementation, an error self-calibration circuit is also designed. Simulation results indicate that SNR can he nearly independent of the signal strength.     

喜马拉雅山亚东段蚂蚁群落研究

为了揭示喜马拉雅山蚂蚁多样性规律,采用样地调查法研究了喜马拉雅山亚东段蚂蚁群落。在北坡、山间谷地和南坡采集蚂蚁标本12 354头,隶属于2亚科8属12种。北坡和山间谷地蚂蚁群落的优势种均为光亮黑蚁(Formica candida Smith),而南坡的优势种为史密西红蚁(Myrmica smythiesii Forel)。亚东段不同海拔样地蚂蚁群落多样性指数中Fisherα指数为0~0.95,Shannon-Wiener指数为0~0.98,显示该地段物种多样性非常低。利用Estimate S 9.1.0程序对该地区蚂蚁物种丰富度进行估计并绘制物种累积曲线,结果表明蚂蚁物种实际观察值接近该地区蚂蚁丰富度估计值。南北坡蚂蚁物种丰富度随海拔升高先增加后降低,丰富度垂直分布格局符合"中域效应"假说。相似性系数分析表明,该地段蚂蚁群落组成和分布受植被类型和海拔影响。     

退火对硒镓银单晶中富Ga2Se3第二相脱溶物的影响

硒镓银单晶体在ＡｇＣａＳｅ２粉末包裹下进行退火，差热分析和红外透过率的测量结果表明，晶体中富Ｇａ２Ｓｅ３第二相脱溶物被消除，显著地改善了ＡｇＧａＳｅ２晶体的透明度。     

A constructive hypothesis test for the single-index models with two groups

Comparison of two-sample heteroscedastic single-index models, where both the scale and location functions are modeled as single-index models, is studied in this paper. We propose a test for checking the equality of single-index parameters when dimensions of covariates of the two samples are equal. Further, we propose two test statistics based on Kolmogorov–Smirnov and Cramér–von Mises type functionals. These statistics evaluate the difference of the empirical residual processes to test the equality of mean functions of two single-index models. Asymptotic distributions of estimators and test statistics are derived. The Kolmogorov–Smirnov and Cramér–von Mises test statistics can detect local alternatives that converge to the null hypothesis at a parametric convergence rate. To calculate the critical values of Kolmogorov–Smirnov and Cramér–von Mises test statistics, a bootstrap procedure is proposed. Simulation studies and an empirical study demonstrate the performance of the proposed procedures.     

Numerical simulation based on two-directional freeze and thaw algorithm for thermal diffusion model

Freeze-thaw processes significantly modulate hydraulic and thermal characteristics of soil. The changes in the frost and thaw fronts (FTFs) affect the water and energy cycles between the land surface and the atmosphere. Thus, the frozen soil comprising permafrost and seasonally frozen soil has important effects on the land surface hydrology in cold regions. In this study, a two-directional freeze and thaw algorithm is incorporated into a thermal diffusion equation for simulating FTFs. A local adaptive variable-grid method is used to discretize the model. Sensitivity tests demonstrate that the method is stable and FTFs can be tracked continuously. The FTFs and soil temperature at the Qinghai-Tibet Plateau D66 site are simulated hourly from September 1, 1997 to September 22, 1998. The results show that the incorporated model performs much better in the soil temperature simulation than the original thermal diffusion equation, showing potential applications of the method in land-surface process modeling.     

Mapgis在土地整理项目中的应用技巧研究

当前Mapgis软件的数字制图技术已广泛应用于土地开发整理规划中的图件编制工作．文章从Mapgis软件和土地整理的概念出发，主要就Mapgis软件的图层操作、报袁定义、整图变换及属性输出功能在土地整理项目绘图中的应用技巧作了深入研究．     

The Bergman Kernel on Some Hartogs Domains

We obtain new explicit formulas for the Bergman kernel function on two families of Hartogs domains. To do so, we first compute the Bergman kernels on the slices of these Hartogs domains with some coordinates fixed, evaluate these kernel functions at certain points off the diagonal, and then apply a first order differential operator to them. We find, for example, explicit formulas for the kernel function on

$$\begin{aligned} \left\{ (z_1,z_2,w)\in \mathbb {C}^3:e^{|w|^2}|z_1|^2+|z_2|^2<1\right\} \end{aligned}$$

and on

$$\begin{aligned} \left\{ (z_1,z_2,w)\in \mathbb {C}^3:|z_1|^2+|z_2|^2+|w|^2<1+|z_2w|^2\;\mathrm{and} \;|w|<1\right\} . \end{aligned}$$

We use our formulas to determine the boundary behavior of the kernel function of these domains on the diagonal.