空间高效硅太阳电池减反射膜设计与数值分析

结合AM0太阳光谱特性对空间硅太阳电池的减反射膜进行了设计分析,得到了最小反射时的最佳膜厚.分别讨论了单、双、三层减反射膜厚度变化对反射率的影响,并对有钝化层的Si O2 (94 nm) / Ti O2 (6 0 nm)双层减反射膜进行了优化设计,优化后硅太阳电池的短路电流和效率分别提高了2 .1%和1.4 % .     

五号桩—长堤地区沙河街组砂体储集性及控制因素研究

沙河街组是沾化凹陷东部五号桩-长堤地区重要的储油层系，主要目的层段为沙三段和沙二段。沙三段和沙二段主要发育有浊积扇、水下冲积扇和滩坝沉积体系，在浊积扇、水下冲积扇中发育辫状水道、扇中前缘、辫状水道间以及扇根、扇缘等沉积微相类型，其中辫状水道、扇中前缘砂体物性好，原生孔隙及次生孔隙均较发育，辫状水道间以及扇根砂体物性较差。其储集特征主要受岩性、沉积微相、成岩作用等因素控制，结合该地区实际情况，将沙二段、沙三段储集层划分为好、中、差3种类型。图4表1参7     

The stability robustness determination of state space models with real unstructured perturbations

This paper considers the robust stability of a linear time-invariant state space model subject to real parameter perturbations. The problem is to find the distance of a given stable matrix from the set of unstable matrices. A new method, based on the properties of the Kronecker sum and two other composite matrices, is developed to study this problem; this new method makes it possible to distinguish real perturbations from complex ones. Although a procedure to find the exact value of the distance is still not available, some explicit lower bounds on the distance are obtained. The bounds are applicable only for the case of real plant perturbations, and are easy to compute numerically; if the matrix is large in size, an iterative procedure is given to compute the bounds. Various examples including a 46th-order spacecraft system are given to illustrate the results obtained. The examples show that the new bounds obtained can have an arbitrary degree of improvement over previously reported ones. This work has been supported by the Natural Sciences and Engineering Research Council of Canada under Grant No. A4396.     

参数空间中鲁棒稳定性问题

本文研究了单输入多输出(SIMO)和多输入单输出(MISO)线性定常控制系统在对象 参数扰动下的鲁棒稳定性问题,并对一给定的控制器,系统在标称参数P°下闭环渐稳的情 况,提出了在参数空间中构造比中心位于P°的最大稳定超球还要大的稳定超球的方法,从而 改善了鲁棒稳定性判据.     

最大似然反褶积软件包的研制与应用

本文简明地介绍最大似然反褶积的基本原理、软件包的研制过程和应用效果。 最大似然反褶积是美国80年代研究出的一种地震资料处理新方法,它有效地解决了传统褶积模型中无法进行信噪分离的矛盾。经松辽盆地实践证明,它可以求出高分辨率和高信噪比的反射系数、最小相位化子波、合成记录、相对层速度和绝对层速度。与国外的VELOG和SEISLOG处理软件的处理结果相比,分辨率和信噪比均有很大的提高。 在软件包的研制过程中,我们主要解决了数学模型复杂和运算速度慢的问题,使最大似然反褶积在CYBER-855S计算机上成为可实用的数字处理技术。 该项技术在大庆油田朝阳沟地区进行了初步应用,结果表明,对薄层地震响应的分辨能力有明显的提高。与井岩性柱状图对比,6m以上的砂层都可以分辨出来,并且对应得比较准确。有些3m的薄层也可以找到。 该软件包的研制成功并在地震资料处理中得到应用,这在国内是首创。     

轴对称空间问题的塑性解法

本文从理想材料轴对称弹塑性问题的所有基本方程出发,研究了全塑性时轴对称空间问题的塑性应变分布规律和应力场,并推导了控制应力分布的定解方程,给出了全塑性轴对称问题的通用解法。     

基于蚁群算法的区域覆盖卫星星座优化设计

首先建立了以区域覆盖性能为目标的卫星星座参数优化模型,通过在连续域定义新的蚂蚁分类与转移策略改进了蚁群算法,使算法能够兼顾多目标优化时目标不兼容的情况,给出了基于该算法实现星座参数优化的框架。优化仿真实验验证了该算法的有效性,可为星座方案决策提供有力的支持。     

中国传统园林建筑审美意向的基本特征初探

本文以中国传统园林建筑为基点,结合艺术理论和具体的艺术形象,对传统园林建筑的基本元素、空间组织,整体形式和气氛表达进行了分析,并探讨其运用于当代设计条件的方式。     

STATIONARY AND NON-STATIONARY STATE SPACE MODELS

Abstract. The concepts of time invariance, stationarity, non-stationarity and immemorial time are considered for state space models (SSMs). Necessary and sufficient conditions for stationarity are given and connected with standard conditions. Expressions are given for the unconditional mean and covariance matrix of the state of a time-immemorial SSM. Application of the results is made to a variety of theoretical and empirical models and the initialization of the Kalman filter in the non-stationary case and for the ARIMA ( p, d, q ) model.     

Decomposition of Time Series Dynamic Linear Models

This paper derives the admissible decompositions for a time series dynamic linear model, assuming only that the model is observable. The decompositions depend on factorizations of the characteristic polynomial of the state evolution matrix G into relatively prime factors. This generalizes the method of West (1997 ) which considers one decomposition in the particular case where G is diagonalizable. Conditions are derived for a decomposition to be independent. These results show that no autoregressive process of order d has an independent decomposition for any integer d . Two illustrations of this procedure are discussed in detail.