【摘 要】
:
In this paper, based on the non‐equidistance GM(1,1)Models mechanism, we obtain a conclusionthat the background value is very important to the accuracy of the gray theoretical modeling. Based onnumeri
【机 构】
:
Dept of Math,Wenhua College,Wuhan,Hubei,430074 Co
论文部分内容阅读
In this paper, based on the non‐equidistance GM(1,1)Models mechanism, we obtain a conclusionthat the background value is very important to the accuracy of the gray theoretical modeling. Based onnumerical integration principle, Simpson formula with changeable steps was deduced to optimizing thebackground value of GM(1,1)model. The example shows that the prediction accuracy of GM(1,1)model issignification improved by the using the optimized background formula.
其他文献
Metal-organic gels(MOGs) are intriguing porous materials for their special properties,such as gas storage,seperation,catalysis,sensing.1 Traditional MOGs are mostly constructed by the derivatives of p
含氧与含氮杂环化合物是一类重要的有机合成中间体并且在天然产物中广泛存在,而分子内的亲核取代反应是构筑这类化合物最直接、最经典的方法之一,但是分子内的亲核取代反应通常需要比较剧烈的反应条件而且官能团适应性不佳,因此,近二十年来,利用过渡金属催化进行环化反应合成含氧、含氮杂环化合物引起了越来越多有机化学家的关注,但过渡金属催化的反应具有一些普遍的缺点,如过渡金属催化剂的价格一般比较昂贵以及催化剂较难在
Direct C-H bond functionalization has attracted much attention due to high atom economy.Recently,reactions catalyzed by diselenide have been successfully applied in alkene functionalization such as am
3-amino allylic alcohols are versatile synthetic intermediates and could be conveniently converted to many useful organic compounds by known methods.Direct amination of carbon-hydrogen bonds is an ide
Carbon-carbon bond cleavage by means of transition metals has received considerable attentions,which provides new opportunities for the discovery of synthetically useful reactions that are otherwise d
In small molecule drug discovery,difluoromethylene group(CF2) is a popular functional group because it can functionalize as a bioisostere of a carbonyl group or an oxygen atom,and would have significa
Indolo[2,1-α isoquinoline is one of the most attractive frameworks with a wide range of biological and pharmacological activities(Figure 1).1 Herein,we described a visible-light induced formal [4+1] a
本文考虑分数阶累加GM(1,1)模型与GM(1,1)模型间的变换关系,论述分数阶累加GM(1,1)模型的两种形式(白化型FAGM(1,1,W)和内涵型FAGM(1,1,C)).分析两种形式模型的解,从理论上讨论了两个模型解间的相对误差.将两个模型解进行展开,得到时间项因子和常数项,发现两类模型解间的误差主要由时间项因子决定.通过建立时间项因子间相对误差与发展系数和序列长度间的函数关系,定量分析了相
偏好投票选举是由多人共同参与投票过程,制定决策(投票)规则,选用合适的方法集结决策信息(信息集结),选择群体满意方案。Cook和Kress[Management Science36(11)(1990)1302]提出了A data envelopment Model for aggregationpreference ranking(DEA Model).该模型是Borda投票模型的推广,但是它没有
为了全面提高复杂装备费用的合理使用度,构建了复杂装备费用测算的灰色自忆性组合模型,借助自忆性预测技术来提高其预测精度.该模型通过有机耦合自忆性原理与传统灰色模型,综合了两者各自的优势.系统的自忆性方程包含多个时次初始场而不仅是单个时次初始场,从而克服了传统灰色预测模型对初值比较敏感的弱点.对复杂装备费用测算的实例研究结果表明,所提出的灰色自忆性组合模型能够充分利用系统的多个历史资料,可以紧密捕捉系