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1.
高速公路交通事故灰色Verhulst预测模型   总被引:4,自引:2,他引:2  
在分析我国高速公路交通事故历史数据的基础上,引入灰色Verhulst预测理论,建立了高速公路交通事故灰色Verhulst预测模型.通过对2000~2007年我国高速公路交通事故死亡人数进行实例分析,发现灰色Verhulst模型的预测精度高于GM(1,1)模型.结果表明,灰色Verhulst模型的预测结果较好的反映了高速公路交通事故的发展趋势,该模型用于高速公路交通事故预测是可行的.  相似文献   

2.
对灰色模型做了进一步的研究,拓广了灰色模型,建立了一个新的、预测精度较高的新灰色预测模型——"对数函数——幂函数变换"模型,并利用此模型对我国博士后研究人员增量做出精度较高的灰色预测.  相似文献   

3.
本文简介了邓聚龙教授在《灰色控制系统》一书中提出的灰色预测模型,并编写了相应的预测程序,对大庆石化总厂主要产品年统计量进行预测、得到了今人满意的结果。  相似文献   

4.
基于品牌手机未来销量预测   总被引:1,自引:0,他引:1  
本文是用灰色预测GM(1,1)模型,探讨了手机销售总数量动态变化,为手机生产提供参考。同时用灰色关联度,来计算总销售量对需要预测的品牌影响,以关联度作为权重,来预测目标品牌。结果表明,对手机销售数量的历史趋势拟合程度较高,所以用此预测模型预测,具有一定的参考价值。  相似文献   

5.
规划人口的动态灰色预测   总被引:2,自引:0,他引:2  
祝精美 《工科数学》1997,13(4):20-23
本运用灰色系统理论,提出了规划人口规模的灰色预测方法,并通过对某市人口的预测,验证了该方法的预测结果是较为符合实际的。  相似文献   

6.
本文运用灰色系统理论,提出了规划人口规模的灰色预测方法,并通过对某市人口的预测,验证了该方法的预测结果是较为符合实际的.  相似文献   

7.
邵民智 《运筹与管理》2001,10(4):102-109
尝试应用灰色系统理论的GM(1,N)和GM(1,1)建模方法,结合有关实际统计资料,研究上海城市居民消费恩格尔系数的主要影响因素和变化趋势,并进行灰色预测。  相似文献   

8.
基于灰色系统理论的城市火灾预测分析   总被引:9,自引:0,他引:9  
提出利用灰色系统理论对城市火灾进行预测的合理性 ,在一般灰色系统模型 GM(1 ,1 )的基础上 ,通过利用等维灰色递补动态预测模型为基础对原始数据预处理及变换后 ,结合对城市火灾按不同分时段进行预测比较 ,最后以某市近年来的火灾状况为例进行了预测 ,结果表明基于灰色系统理论进行分时段预测城市火灾发生时结果更精确 .  相似文献   

9.
在离散灰色预测DGM(1,1)模型的基础上,提出了新陈代谢离散灰色预测M DGM(1,1)模型,即:对原始数据序列采用新陈代谢的方式逐次建立相应的DGM(1,1)模型,并把该模型用于江西省旅游收入的中长期预测,最后进行了精度检验.结果表明:新陈代谢离散灰色预测M DGM(1,1)模型预测精度较高,可作为中长期预测的工具.  相似文献   

10.
本文运用灰色系统灾变预测理论,建立了武安市二代棉铃虫发生量预测模型.从而对武安市未来年份棉铃虫卵量进行预测.  相似文献   

11.
基于灰色马尔科夫模型的平顶山市空气污染物浓度预测   总被引:1,自引:0,他引:1  
选用平顶山市2005—2009年各空气污染物浓度作为原始数据序列,建立灰色马尔科夫预测模型,对未来10年的污染因子浓度进行预测.模型检验结果表明:均方差比值和小误差概率均为一级;运用灰色关联分析法计算各污染物原始数据序列与预测数据序列之间的关联度,定量描述灰色马尔科夫预测模型对于空气质量预测的精确度,平均精度达到99.9%,表明灰色马尔科夫预测模型对于空气质量预测有很高的实用性.  相似文献   

12.
以武汉市农村人均收入为样本,将灰色预测模型和马尔可夫链预测模型相结合,通过对比预测的数据信息与实际数据信息差距,对2011年和2012年武汉市农村人均收入进行了预测计算.根据相关模拟检验与残差修正,灰色马尔可夫链可视为农村人均收入预测的可行且有效的方法.结果显示,单纯地运用灰色模型,预测值与实际值的误差均值是0.687%;通过马尔可夫链模型的二次模拟得到的误差明显减小.  相似文献   

13.
The binary reflected Gray code function b is defined as follows: If m is a nonnegative integer, then b(m) is the integer obtained when initial zeros are omitted from the binary reflected Gray code of m.This paper examines this Gray code function and its inverse and gives simple algorithms to generate both. It also simplifies Conder's result that the jth letter of the kth word of the binary reflected Gray code of length n is
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14.
15.
Let be a collection of subsets of . In this paper we study numerical obstructions to the existence of orderings of for which the cardinalities of successive subsets satisfy congruence conditions. Gray code orders provide an example of such orderings. We say that an ordering of is a Gray code order if successive subsets differ by the adjunction or deletion of a single element of . The cardinalities of successive subsets in a Gray code order must alternate in parity. It follows that if is the difference between the number of elements of having even (resp. odd) cardinality, then is a lower bound for the cardinality of the complement of any subset of which can be listed in Gray code order. For , the collection of -blockfree subsets of is defined to be the set of all subsets of such that if and . We will construct a Gray code order for . In contrast, for we find the precise (positive) exponential growth rate of with as . This implies is far from being listable in Gray code order if is large. Analogous results for other kinds of orderings of subsets of are proved using generalizations of . However, we will show that for all , one can order so that successive elements differ by the adjunction and/or deletion of an integer from . We show that, over an -letter alphabet, the words of length which contain no block of consecutive letters cannot, in general, be listed so that successive words differ by a single letter. However, if and or if and , such a listing is always possible.

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16.
A binary Gray code G(n) of length n, is a list of all 2nn-bit codewords such that successive codewords differ in only one bit position. The sequence of bit positions where the single change occurs when going to the next codeword in G(n), denoted by S(n)?s1,s2,…,s2n-1, is called the transition sequence of the Gray code G(n). The graph GG(n) induced by a Gray code G(n) has vertex set {1,2,…,n} and edge set {{si,si+1}:1?i?2n-2}. If the first and the last codeword differ only in position s2n, the code is cyclic and we extend the graph by two more edges {s2n-1,s2n} and {s2n,s1}. We solve a problem of Wilmer and Ernst [Graphs induced by Gray codes, Discrete Math. 257 (2002) 585-598] about a construction of an n-bit Gray code inducing the complete graph Kn. The technique used to solve this problem is based on a Gray code construction due to Bakos [A. Ádám, Truth Functions and the Problem of their Realization by Two-Terminal Graphs, Akadémiai Kiadó, Budapest, 1968], and which is presented in D.E. Knuth [The Art of Computer Programming, vol. 4, Addison-Wesley as part of “fascicle” 2, USA, 2005].  相似文献   

17.
18.
IIntroductlonA.Galois ringLet GR(4”)be the Gajois ring of characteristic 4 with 4”elements.In GR(4”)thereexists a nonzero element ’of order 2”一1.Let T={0,1,,…,矿-‘};then any elementc e GR(4”)can be writt。unlqllely sc=a十 Zb,a。 E丁,whi山 is called 2-adic representation ofc.The elemem c can also be written unl叩ely sc=ac + al卜…+am矿‘,a;E凤,(0<6<。一 1),whi血is called the additive representation of c.It is。11协。n that GR(”)/切。见。,where (2 is the pr…  相似文献   

19.
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