基于GM(1,1)水泥产量预测模型

运用灰色系统理论中的GM(1,1)灰色预测模型,以全国近7年来的水泥产量为例,对其未来几年的生产状况进行科学预测,为今后的生产提供科学依据.     

水泥强度的模糊预测模型研究

本文根据水泥强度的模糊性 ,运用模糊模式识别理论 ,建立了预测水泥强度的模糊贴近度模型 .通过对上海水泥厂提供的实测数据进行模糊计算 ,得到了令人满意的结果 ,为水泥强度的快速预测提供了一种新方法 ,有较好的实用价值 .     

水泥强度的模糊预测模型研究

本根据水泥强度的模糊性，运用模糊模式识别理论，建立了预测水泥强度的模糊贴近度模型。通过对上海水泥厂提供的实测数据进行模糊计算，得到了令人满意的结果，为水泥强度的快速预测提供了一种新方法，有较好的实用价值。     

基于非线性主成分神经网络水泥强度预测研究

研究非线性主成分分析法与神经网络算法的融合模型,并将非线性主成分神经网络融合模型应用于水泥强度的预测研究,得到的结果表明预测误差很小,可见研究结果可用于指导水泥生产实践.     

水泥回转窑的模糊控制模型

水泥回转窑由于其控制量的迟滞性及不敏感性难以用传统的方法进行控制 .本文讨论用模糊控制的方法来模拟水泥回转窑的人工控制     

水泥回转窑的模糊控制模型

水泥回转窑回由于其控制量的迟滞性及不敏感性难以用传统的方法进行控制，本讨论用模糊控制的方法来模拟水泥回转窑的人工控制。     

基于注意力机制的ADE-Bi-IndRNN模型的中国粮食产量预测

为更加准确地预测我国粮食总产量,基于自适应差分进化算法来智能地选择基于注意力机制的双向独立循环神经网络的超参数,并考虑了粮食作物单位产量、农业生产条件、科技因素、农业保险、市场及经济因素五大类影响因素,构建了基于注意力机制的ADE-Bi-IndRNN粮食产量预测模型。经过预测分析得出我国2020—2024的粮食产量分别为6.67亿吨、6.72亿吨、6.80亿吨、6.99亿吨、7.02亿吨,总体呈现震荡上涨趋势,平均年增长率为1.15%。同时,通过对多个变量进行的注意力权重的分析,发现现阶段对我国粮食总产量预测贡献最大的三个变量为：谷物单位面积产量,粮食作物总播种面积,耕地灌溉面积,且政府对农业保险的政策性补贴、粮食进口量、谷物生产价格指数、农业生产资料指数也有助于提升我国的粮食总产量,并据此对我国粮食行业发展提出了建议。     

组合模型在我国能源需求预测中的应用

文章首先比较了不同的能源需求预测方法的特点,并选择确定性加随机性时间序列组合模型对我国能源需求进行预测,然后详细介绍了建模的过程,并对模型预测精度和参数稳定性作了评价,结果表明本文采用的组合模型是一种比较有效的预测方法,最后用该模型对我国2004~2020能源需求进行了预测。     

基于灰色GM(1,1)模型的跨境电子商务发展前景预测分析

采用灰色模型对我国2013年至2016年跨境电子商务进行预测,对预测结果作了残差检验,并对我国发展跨境电子商务提出了建议,预测结果将对我国跨境电子商务的管理者和从业者起到参考作用,具有一定的应用价值.     

灰色组合模型及其应用

本建立了GM(1．1)与线性回归模型的组合模型，改进了单一模型的局限性，并用此模型预测了郑州市粮食总产量，得到了较为满意的结果。     

Interpolation solution in generalized stochastic exponential population growth model

In this paper, first we consider model of exponential population growth, then we assume that the growth rate at time t is not completely definite and it depends on some random environment effects. For this case the stochastic exponential population growth model is introduced. Also we assume that the growth rate at time t depends on many different random environment effect, for this case the generalized stochastic exponential population growth model is introduced. The expectations and variances of solutions are obtained. For a case study, we consider the population growth of Iran and obtain the output of models for this data and predict the population individuals in each year.     

A theoretical evaluation method for mechanical sealing integrity of cementing sheath

The sealing integrity of cement sheath directly affects the service life of oil and gas wells, and plays an important role in oil well operation and production. In this paper, the evaluation of sealing integrity of cement sheath was divided into two parts: the integrity of formation and cement sheath, and the integrity of cement sheath and casing. Based on the convergence-constraint theory, the effect of convergence stress generated by formation on cement slurry during the hardening process was considered. And the evaluation method for casing-cement-formation sealing integrity was established. In addition, a quantitative relationship between compressive strength of cement sheath and formation characteristic parameters was proposed to determine the cement-formation sealing integrity. Besides, the integrity evaluation method of casing-cement-formation combination was verified by tensile strength, compressive strength and plastic zone of cement. The field application analysis showed that this method is valid to predict the cement failure. During the cementing operation, the integrity of casing-cement-formation interface can be controlled by adjusting the properties of the cement sheath.     

基于灰色微分方程的传染病预测

本文归纳总结了传染病的几类预测方法,并通过一个例子,将灰色模型和微分方程模型结合,用于传染病的预测.     

Modelling and simulation of injecting acrylic bone cement into osteoporotic vertebral bones within percutaneous vertebroplasty

Percutaneous vertebroplasty is a common clinical procedure to treat vertebral compression fractures and osteoporotic vertebral bodies. However, this operation technique is accompanied by different complications due to lack of knowledge about the complicated behaviour of bone cement within the human body. To contribute to a better understanding of the processes that take place inside the body during a vertebroplasty, a detailed model of the thermomechanical behaviour of acrylic bone cement has been developed. All important effects are covered, that influence the behaviour of acrylic bone cement during the injection in a human vertebral body. Implemented in the opensource CFD-code OpenFOAM^®, first results show that this comprehensive simulation of the minimal invasive injection is capable to accurately predict the cement distribution and temperature field of acrylic bone cement inside the vertebral body. (© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

低密度和高密度水化硅酸钙的纳米压痕数值模拟

水化硅酸钙(C-S-H)是决定以硅酸盐水泥为主要组分的水泥基材料性能的关键组分,水化硅酸钙(C-S-H)是存在于水化产物中连续的固体物质,占水化水泥浆体体积的50%～60%,是水泥浆体中决定硬化水泥浆体物理结构和性能的主要成分,同时水化硅酸钙(C-S-H)也是混凝土结构宏观尺度的凝聚性和耐久性的重要影响因素．模型的建立对于预测水泥的体积性能如收缩、蠕变、渗透率和裂缝等方面越来越重要．通过将水化硅酸钙(C-S-H)分为低密度和高密度两种数值模型,并且将水化硅酸钙(C-S-H)视为在纳米尺度上具有实际微观粒子性能的离散颗粒的集合,运用分子动力学方法,通过控制水化硅酸钙(C-S-H)的紧密堆积体积分数和保持颗粒级别的其他材料属性不变来进行纳米压痕实验模拟,进而验证了压痕模量和硬度符合纳米压痕实验数据的规律．     

A RAPID APPROXIMATION FOR PREDICTING THE HYDROCARBON DISCOVERY RATE: PART 2. IMPROVING THE ACCURACY

In Part 1 of this paper, we noted the systematic errors in the estimates of means and standard deviations produced by a rapid approximation applied to a model of hydrocarbon discovery. In Part 2, we apply regression to predict the approximation errors, as functions of model parameters and approximation output. With the regression model, we can correct much of the error in the approximation, as we illustrate with data from the Nisku-Shelf play of western Canada.     

水泥生产的质量——成本控制与优化

对影响水泥的 8个质量指标的 5个因素进行对称一单纯形设计与试验 ,用混料规范多项式拟合响应曲面 ,建立质量一成本控制优化的数学模型 ,对理论最优解的利益区域进行极端顶点设计并按排小磨试验 ,确定质量较好成本较低的水泥生产方案 .     

我国工业研发存量对产出增长的影响及发展策略——基于后危机时代省际面板数据分析

在构建工业研发存量对产出增长影响的理论模型的基础上,通过面板数据模型实证分析后危机时代(2008年以来)我国工业研发存量对其产出增长的影响,研究发现:从全国来看,工业研发存量对产出增长的产出弹性为0.16%;从各地区的对比来看,中部地区的产出贡献度最大,产出弹性达到0.59%,西部地区次之,产出弹性为0.21%,东部地区产出贡献度最小,产出弹性仅为0.08%.在此基础上,提出进一步提高我国工业研发存量对产出增长贡献度的对策建议.