辽宁装备制造业竞争力研究

运用离散系数加权法对国内31个省市自治区的装备制造业竞争力进行综合比较分析。研究发现,辽宁装备制造业综合竞争力较强,8个子行业中有4个在全国处于比较优势地位,另外4个竞争力也较强;各子行业在规模指标上竞争力均较强,8个子行业的资产总计和利税总额都在全国处于比较优势地位;各子行业的结构与效率指标在全国无明显优势。因此,只有优化装备制造业的结构与效率指标,才能促进辽宁装备制造业的进一步发展。     

中国碳排放预测与影响因素分析

中国经济的高速发展带来了碳排放的快速增加.总结目前国内外所使用的碳排放预测方法,讨论国内外碳排放的影响因素;应用离散二阶差分方程预测模型(DDEPM),预测中国2020年的碳排放量与GDP数值,结果表明中国未来10年碳排放增长速度依旧很快,单位GDP的碳排放降低潜力巨大;通过文献检索、专家咨询、问卷调查与头脑风暴相结合的方法,建立中国碳排放影响因素体系;运用应用结构解释模型(ISM)对其进行聚类分析,经过UCINET模拟,将影响因素体系划分为5个聚类;根据聚类中影响因素的相互关系,分析各个聚类中的关键影响因素,从而得出中国碳排放影响因素体系中的5个关键因素.     

历史上的连续性思想和离散性思想

本文从连续性和离散性这两个概念出发,对物理学史做了一个简单地梳理。连续性和离散性是物理学史上两个非常重要的概念,它们在不同的历史阶段有着各自的理论形态。研究这两种不同的思想传统为进一步理解20世纪的量子力学争论有所帮助。     

Estimating Mixing Densities in Exponential Family Models for Discrete Variables

This paper is concerned with estimating a mixing density g using a random sample from the mixture distribution f(x)=∫f x | θ)g(θ)dθ where f(· | θ) is a known discrete exponen tial family of density functions. Recently two techniques for estimating g have been proposed. The first uses Fourier analysis and the method of kernels and the second uses orthogonal polynomials. It is known that the first technique is capable of yielding estimators that achieve (or almost achieve) the minimax convergence rate. We show that this is true for the technique based on orthogonal polynomials as well. The practical implementation of these estimators is also addressed. Computer experiments indicate that the kernel estimators give somewhat disappoint ing finite sample results. However, the orthogonal polynomial estimators appear to do much better. To improve on the finite sample performance of the orthogonal polynomial estimators, a way of estimating the optimal truncation parameter is proposed. The resultant estimators retain the convergence rates of the previous estimators and a Monte Carlo finite sample study reveals that they perform well relative to the ones based on the optimal truncation parameter.     

Computation of exact confidence intervals from discrete data using studentized test statistics

A new area of research interest is the computation of exact confidence limits or intervals for a scalar parameter of interest from discrete data by inverting a hypothesis test based on a studentized test statistic. See, for example, Chan and Zhang (1999), Agresti and Min (2001) and Agresti (2003) who deal with a difference of binomial probabilities and Agresti and Min (2002) who deal with an odds ratio. However, neither (1) a detailed analysis of the computational issues involved nor (2) a reliable method of computation that deals effectively with these issues is currently available. In this paper we solve these two problems for a very broad class of discrete data models. We suppose that the distribution of the data is determined by (,) where is a nuisance parameter vector. We also consider six different studentized test statistics. Our contributions to (1) are as follows. We show that the P-value resulting from the hypothesis test, considered as a function of the null-hypothesized value of , has both jump and drop discontinuities. Numerical examples are used to demonstrate that these discontinuities lead to the failure of simple-minded approaches to the computation of the confidence limit or interval. We also provide a new method for efficiently computing the set of all possible locations of these discontinuities. Our contribution to (2) is to provide a new and reliable method of computing the confidence limit or interval, based on the knowledge of this set.     

自举式扫描电路的分析及改进

从自举式扫描电路的补偿状态、电路的改进措施和ε曲线簇三个方面全面分析了自举式扫描电路的基本原理,并为设计自举式扫描电路提供了理论依据。     

On The Method of Discrete Probability Distributions in Risk and Reliability Calculations–Application to Seismic Risk Assessment

If the point of view is adopted that in calculations of real-world phenomena we almost invariably have significant uncertainty in the numerical values of our parameters, then, in these calculations, numerical quantities should be replaced by probability distributions and mathematical operations between these quantities should be replaced by analogous operations between probability distributions. Also, practical calculations one way or another always require discretization or truncation. Combining these two thoughts leads to a numerical approach to probabilistic calculations having great simplicity, power, and elegance. The philosophy and technique of this approach is described, some pitfalls are pointed out, and an application to seismic risk assessment is outlined.     

渐变光波导的耦合模分析

从电磁场互易原理得到了本地耦合模方程,并用高斯定理证明了功率守恒式。首次得到了两相同渐变光波导耦合模方程的严格解析解,指出了已往近似结果的局限性。     

HFC网中的离散小波多音调制技术研究

针对HFC网上行信道窄带噪声的环境,研究了HFC网中的离散小波多音调制技术,并对离散小波多音调制技术和离散多音调制技术进行了比较。计算机仿真结果表明,离散小波多音调制子信道幅频响应特性远优于离散多音调制。离散小波多音调制通过精心设计子信道使其具有极佳的幅频响应特性曲线,具有比离散多音调制更强的抑制信道间干扰的能力。     

单模光纤中光的偏振

分析了单模光纤中光的偏振特性以及偏振光学在光纤中的应用