地区电力需求预测研究

本文在分析影响预测准确原因的基础上．指出预测工作必须定量与定性相结合．针对地区电力消费需求的特点，提出了适宜于定性分析的四个预测模型．运用上述模型，实际预测结果令人满意。     

基于主成分分析的伊犁州直县(市)综合实力评价研究

主成分分析就是利用降维的思想,在损失很少信息的前提下把多个指标转化为几个综合指标的多元统计方法.通过对伊犁州直属10个县市的18项指标基于主成分分析进行了定量分析,得到了10个县市的综合实力排名,并指出了各县市经济发展不平衡的原因,给出了相应参考政策.     

应用激光全息干涉术及有限元法对2050热连轧机机座自振特性的三维分析

根据相似理论,进行了宝山钢铁总厂热轧厂2050热连轧精轧机机座自振特性的三维模拟研究,并应用全息干涉术进行了前三阶主振型分析.本文还进行了三维有限元数值分析与模拟值进行了映照.二者结果是吻合的.     

Sensitivity analysis of a greedy heuristic for knapsack problems

In this paper, we carry out parametric analysis as well as a tolerance limit based sensitivity analysis of a greedy heuristic for two knapsack problems—the 0–1 knapsack problem and the subset sum problem. We carry out the parametric analysis based on all problem parameters. In the tolerance limit based approach, we use a definition of the sensitivity analysis problem that is polynomial for polynomial heuristics. One of the interesting and counterintuitive results described in this paper is that the tolerance limits obtained from the heuristic sensitivity analysis cannot be used as bounds for the tolerance limits of the sensitivity analysis of optimal solutions in most cases.     

聚类分析在股票市场板块分析中的应用

本文将聚类分析应用于股票市场的研究,研究实例表明,聚类分析方法是股市板块分析中的一种有效、实用的方法     

Scalar Conservation Laws and Spatially Dependent Flux Functions

In this paper, we carry out a detailed analysis of the signaling and initial value problems associated with a general scalar conservation law that admits spatial variation in the flux function. The approach adopted here is to introduce a nonlinear phase variable directly into the problem and carry out the analysis in the space and phase variables rather than in space-time. This facilitates our efforts to create, through a bifurcation analysis, a clear picture of the process by which a smooth wave breaks to generate a propagating shock wave.     

A perturbation method applied to the buckling of a compressed elastica

We consider the problem of carrying out an asymptotic analysis for the phenomenon of bifurcation which occurs at critical values of an axial force applied to an elastic column. In the present setting a discontinuous coefficient precludes the possibility of carrying out the usual asymptotic analysis. The problem is overcome via a nonlinear change of independent variables.     

数值分析双语教学的探讨

首先指出了数值分析双语教学的目的和意义.其次,分析了数值分析双语教学中存在的问题.最后,给出了数值分析双语教学的一些措施.     

Singular perturbation analysis of bistable differential equation arising in the nerve pulse propagation

This paper deals with the numerical analysis of time dependent parabolic partial differential equation. The equation has bistable nonlinearity and models electrical activity in a neuron. A qualitative analysis of the model is performed by means of a singular perturbation theory. A small parameter is introduced in the highest order derivative term. This small parameter is known as singular perturbation parameter. Boundary layers occur in the solution of singularly perturbed problems when the singular perturbation parameter tend to zero. These boundary layers are located in neighbourhoods of the boundary of the domain, where the solution has a very steep gradient. Most of the conventional methods fails to capture this effect. A numerical scheme is constructed to overcome this discrepancy in literature. A rigorous analysis is carried out to obtain a-priori estimates on the solution of the problem and its derivatives. It is then proven that the numerical method is unconditionally stable. Convergence and stability analysis is carried out. A set of numerical experiment is carried out and it is observed that the scheme faithfully mimics the dynamics of the model.     

Theory and inference for regression models with missing responses and covariates

In this paper, we carry out an in-depth theoretical investigation for inference with missing response and covariate data for general regression models. We assume that the missing data are missing at random (MAR) or missing completely at random (MCAR) throughout. Previous theoretical investigations in the literature have focused only on missing covariates or missing responses, but not both. Here, we consider theoretical properties of the estimates under three different estimation settings: complete case (CC) analysis, a complete response (CR) analysis that involves an analysis of those subjects with only completely observed responses, and the all case (AC) analysis, which is an analysis based on all of the cases. Under each scenario, we derive general expressions for the likelihood and devise estimation schemes based on the EM algorithm. We carry out a theoretical investigation of the three estimation methods in the normal linear model and analytically characterize the loss of information for each method, as well as derive and compare the asymptotic variances for each method assuming the missing data are MAR or MCAR. In addition, a theoretical investigation of bias for the CC method is also carried out. A simulation study and real dataset are given to illustrate the methodology.     

随机需求下三度价格歧视重复博弈的研究

基于随机需求函数,讨论了相互竞争的两厂商实施三度价格歧视无限次重复博弈和不定次重复博弈的均衡分析,在三度价格歧视无限次重复博弈分析中,得出了两厂商在贴现因子影响下的子博弈完美纳什均衡.在三度价格歧视不定次重复博弈分析中,设计了不同的方案并进行了Matlab仿真,比较了不同贴现因子下不同仿真方案的厂商得益,并对仿真结果进行了系统分析,得到了统计意义下的均衡分析.     

数学分析教学中学到的和想到的

近代数学分析的教学有将传统的微积分,测度论,复分析和流形上的微积分统一起来讲的趋势;近代数学分析的教学有将数学及其应用,特别是数学在物理中的应用结合起来讲的趋势．     

上证A股指数的分形统计分析--一种新的分析范式

本文介绍了传统证券分析方法所面临的理论和实践的挑战,简明地介绍了分形分析方法的基本理论和应用范围及特点。并采用该方法对我国上海证券交易所A股指数进行了深入分析,指出了上证A股指数具有较强的持续性,不是一个独立的随机游走过程。同时还实证了上证A股指数是分形的。本文还发现了上证A股指数具有12个月、16个月、20个月、23个月、31个月的周期。     

Transient chaos and crisis phenomena in butterfly valves driven by solenoid actuators

Chilled water systems used in the industry and on board ships are critical for safe and reliable operation. It is hence important to understand the fundamental physics of these systems. This paper focuses in particular on a critical part of the automation system, namely, actuators and valves that are used in so-called “smart valve” systems. The system is strongly nonlinear, and necessitates a nonlinear dynamic analysis to be able to predict all critical phenomena that affect effective operation and efficient design. The derived mathematical model includes electromagnetics, fluid mechanics, and mechanical dynamics. Nondimensionalization has been carried out in order to reduce the large number of parameters to a few critical independent sets to help carry out a broad parametric analysis. The system stability analysis is then carried out with the aid of the tools from nonlinear dynamic analysis. This reveals that the system is unstable in a certain region of the parameter space. The system is also shown to exhibit crisis and transient chaotic responses; this is characterized using Lyapunov exponents and power spectra. Knowledge and avoidance of these dangerous regimes is necessary for successful and safe operation.     

A Case History of Nuclear Power Plant Site Selection

This paper discusses a multidisciplinary study conducted to select a site for a nuclear power plant. A series of screening steps was carried out to identify candidate sites for the plant, as well as candidate water sources. Multiobjective decision analysis methods were used to evaluate and rank these candidate sites and water sources; a risk analysis was carried out to determine the effects of major uncertainties. The evaluation concerns considered in the study are discussed, as well as the scales used to measure impacts with regard to these concerns.     

基于DEA模型的装备费用-效能分析

结合装备费用效能分析的特性,利用数据包络分析法(DEA)对装备费用效能决策方案进行评价.通过计算和处理,得到不同方案的有效程度并制定相应调整措施.数据包络析在对装备费用效能分析中具有很强的适用性,且具有广泛的应用价值.     

Dynamical properties of a stochastic predator-prey model with functional response

A stochastic prey-predator model with functional response is investigated in this paper. A complete threshold analysis of coexistence and extinction is obtained. Moreover, we point out that the stochastic predator-prey model undergoes a stochastic Hopf bifurcation from the viewpoint of numerical simulations. Some numerical simulations are carried out to support our results.     

两套种作物的农艺优化教学模型研究

本文是采用回归旋转设计方法，研究两套种作物农艺优化的数学模型．利用计算机模拟仿真，优化农艺方案．示范验证表明，这种试验方法可行，优化方案应用效果显著．     

高强度锚具可靠性分析及夹片曲线概率优化研究

本文用失效树分析法,对现有锚具进行失效分析,计算出失效概率.同时,对锚具主要零件夹片的夹口曲线进行概率优化,使优化后的曲线对在公差范围内合格钢筋的拟合概率最大,从而设计出新的锚具及夹片.夹口曲线的求法也为其它类型锚具夹片的设计提供了一种新的方法.     

Parametric vibration of TMD installed in tall building during seismic excitation

In this paper shaking-table tests of a model-scale building with TMD (tuned mass damper) are conducted. The main aim of the research is to show the influence of kinematical excitation on the dynamic response of the model of tall building with pendulum TMD. The special attention is focused on the functioning of pendulum, which is simultaneously excited by the vertical component of ground motion. There are two kinds of analysis carried out — numerical and experimental. The numerical analysis of the problem is performed with using COSMOS/M system (a FEM numerical model is defined), while experimental analysis is carried out on a physical model-scale building with TMD. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)