S-函数在锅炉动态模型仿真中的应用

本文介绍了Matlab软件包Simulink中的S-函数创建方法,针对锅炉动态模型仿真,通过构建S-函数读取实时数据修正模型系数,实现模型的动态功能,使仿真模型更接近于锅炉实际状态,更好的服务于仿真试验研究。     

Determination of Lateral Extension of Hydrocarbon Concentration Sealing Caprocks by AVO Analysis

The caprock is one of the key factors for a reservoir, especially for a gas reservoir. Whether the caprocks can block off the gas is of significance for the accumulation and preservation of the gas reservoir. In this paper, we use the Amplitude versus offset (AVO) seismic technique to determine the lateral extension of the hydrocarbon concentration sealing caprocks. The essence of this technique is to detect the variations of the reservoir bed physical properties by monitoring the variations of the reflection coefficient of seismic waves upon the interfaces between different lithologies.Generally it is used to indicate hydrocarbon directly. For the hydrocarbon concentration sealing caprocks, the change of hydrocarbon concentration may cause the change of physical properties of the caprocks. Therefore it is possible to evaluate the hydrocarbon concentration sealing ability of the caprocks by AVO. This paper presents a case study using AVO to determine the lateral extension of the hydrocarbon concentration sealing caprocks. The result shows that this method is helpful for the exploration of the region.     

航天产品多源可靠性信息的收集与整理--建立可靠性信息数据库

航天产品可靠性信息的来源多样，可靠性信息的时间性、随机性、有价性、时效性和可追溯性等特征，决定了可靠性数据收集应满足真实性、连续性、完整性等基本要求。同时，对多源信息的收集应遵循先进行需求分析，再确定数据收集点并制定数据收集表格的程度进行。给出了信息的适用性准则和信息分类的三维模型。最后结合具体型号航天产品的可靠性工作的要求，给出了可靠性信息数据库系统的整体方案设计。     

Study on Numerical Simulation of Mold Filling and Solidification Processes under Pressure Conditions

The mold filling and solidification simulation for the high pressure die casting (HPDC) and low pressure die casting (LPDC) processes were studied.A mathematical model considering the turbulent flow and heat transfer phenomenon during the HPDC process has been established and paralled computation technique was used for the mold filling simulation of the process.The laminar flow characteristics of the LPDC process were studied and a simplified model for the mold filling process of wheel castings has been developed.For the solidification simulation under pressure conditions,the cyclic characteristics and the complicated boundary conditions were considered and techniques to improve the computational efficiency are discussed.A new criterion for predicting shrinkage porosity of Al alloy under low pressure condition has been developed in the solidification simulation process.     

2007年纽伦堡国际玩具展

本刊讯:2007年2月1日,一年一度的纽伦堡国际玩具展开幕了。今年纽伦堡国际玩具展启用了新的展览馆,读者们最关心的模型类产品在7号馆。遗憾的是这次展会主办方提供的静态模型参展商图片很少,也许静态模型爱好者会抱怨,不过编辑部会尽力收集更多本届展会静     

基于实码加速遗传算法的土壤水分入渗参数拟合的试验研究

采用人工降雨的方法,通过在甘南县进行的原位降雨入渗实验,揭示黑龙江省西部半干旱区坡耕地的土壤水分入渗规律,并应用实码加速遗传算法完成对入渗模型的参数优化.     

《模型世界》2007年第8期读者调查表

老编:我看见朋友们使用食盐对模型进行旧化,感觉非常好,听说《模型世界》杂志中有过介绍,不知道是哪一期,杂志社还有那期杂志么?如果没有,就麻烦老编给我讲讲吧!成都:罗勇     

基本模糊控制器的研究

分析、研究了基本模糊控制器的模型及其算法，并对其改进型进行了讨论。     

多重线性多项式模型参数估计的A—最优设计

对于ｑ－单纯形利益区域上的ｎ阶多重线性多项式模型，本文讨论了证明了ｎ＝２时Ｓｃｈｅｆｆｅ单纯形一重心设计是Ａ－最优的。     

新滩滑坡非线性动态预测

文章介绍了新滩滑坡概况及其环境地质条件，包括土石性质及其力学指标。在此基础上，从协同学的宏观研究观点出发，以新滩滑坡的时间序列数据为基础，探讨了该滑坡的动态特征：相空间特征及其吸引子，建立了新滩滑坡的非线性动态演化发展模型，初步预测结果令人满意。／