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1.
基于模糊综合评价法的公路路线方案比选   总被引:1,自引:1,他引:0  
为了综合比选公路路线设计方案,必须针对路线方案进行多目标多层次的决策分析。结合公路项目选线的特点与原则,利用改进的层次分析法和模糊综合评价法等系统分析方法,建立了完整可靠的公路路线综合评价指标体系,并利用建立的模糊综合评判模型对公路路线方案的优选进行了实证分析。结果表明,该模型具有较强的系统性、灵活性和实用性。  相似文献   

2.
为科学合理地安排公路建设项目实施序列,在构建公路建设项目排序参数体系的基础上,提出了基于TOPSIS的公路建设项目排序模型。该模型以影响参数为因素指标集,以公路建设项目为论域集,构建了公路建设项目实施序列矩阵,应用[0,1]线性变换将其标准化;充分考虑专家知识经验以及数据本身蕴涵的信息,采用AHP与熵值法综合确定影响参数的权重,并将标准化决策矩阵与参数权重相结合,构造了加权标准化决策矩阵;基于运筹学中的TOPSIS法,确定了公路建设项目的正负理想方案;通过计算公路建设项目与负理想方案的贴近度来确定公路建设项目的实施序列。最后以5条公路建设项目排序为例,验证了该模型的实用性与有效性。  相似文献   

3.
采用加权移动平均法、指数平滑法,结合国民经济发展情况综合利用弹性系数法,分析预测伊犁州直客运总量、公路客运量和分县市客运量.以预测出的客运量为基础,计算伊犁州直各市县的综合客运需求总量和适站量,并结合客运场站布局影响因素,针对市级、中心区级和片区级客运交通枢纽分别进行预测,布局规划伊犁州直客运场站.  相似文献   

4.
公路项目综合评价方法研究   总被引:1,自引:1,他引:1  
基于公路建设项目与社会、经济、环境协调发展的角度考虑,并结合中国国情,作者建立了公路建设项目各指标协调发展的三级评价指标体系即目标层指标、准则层指标和指标层指标.运用模糊数学理论,作者建立了NPV、Nd、IRR、BCR的隶属函数.运用集值统计方法对社会效益指标体系和环境效益指标体系中的七个指标进行了无量纲化处理,得到无量纲矩阵.通过对定量与定性指标的评判,得到单因素评价矩阵.运用AHP法,对若干备选方案作相对评价和综合评价,确定各因素的权重,排列出各方案的优劣次序.根据最大隶属原则,求得了公路项目各指标协  相似文献   

5.
将层次分析法和灰色关联分析的方法有机地结合起来,对招标的建设项目建立灰色多层次综合评判(AHP-GRAP)模型,利用层次分析法计算影响建设项目评标的各个因素的权重,构造各项因素的比较数列和参考数列,计算各个投标方案的关联度,以此来确定参与投标的建筑企业的排序,最后给出了这种模型的应用实例.  相似文献   

6.
为了准确评价公路边坡的稳定性,针对影响公路边坡稳定性因素的模糊性和随机性,选择影响公路边坡稳定性的10个主要因素,并分为两个层次.利用模糊数学综合评判方法,采用专家方法和经验公式法赋予影响因素的隶属函数和隶属值,建立公路边坡稳定性分析的二级综合评判模型,得到公路边坡稳定性的预测结果。将该模型应用于工程实际,结果证明了该方法的切实可行性和有效性。但对影响因素的选择还需要进一步完善和标准化。  相似文献   

7.
为了客观评价双车道公路机动车交通行为安全性,应用神经网络与模糊评判方法,结合空间向量理论,构建了安全评估模型.首先根据国内外机动车交通行为安全性的相关研究成果,选用超速指数、平均车头时距与安全超车视距分别作为自由流超速行为、跟驰行为与超车行为三类机动车交通行为安全性状态判别指标,并提出各指标安全性界定标准.然后利用3层神经网络模型建立了双车道公路运行环境下七个主要指标与机动车交通行为的关系模型,通过部分实测路段数据验证了模型的可靠性;以模糊评判方法为基础,建立了机动车交通行为安全性判别指标的隶属函数,基于评价结果对三类机动车交通行为安全性等级进行了划分;并结合空间向量理论提出综合评价向量以表征机动车交通行为综合安全性.理论分析和实例表明该评估模型可为双车道公路机动车交通行为安全性评估提供一种较为可行的方法.  相似文献   

8.
在对公路沥青路面使用性能及其影响因素充分分析的基础上,利用模糊综合评判数学原理建立了沥青路面使用性能的模糊综合评价模型,并利用该模型对进行了应用分析,实践分析表明,该模型具有较强的实用性。  相似文献   

9.
通过对建设项目合同的三种模式:固定价格合同、单价合同和成本加价合同的分析,建立了评价该模式指标体系,提出了模糊综合评判模型,为选择合适的建设项目合同模式提供一种可靠的分析方法。  相似文献   

10.
结合导致人才流失的组织因素,建立了对企业人才环境评判的指标体系,并运用模糊综合评判模型进行评判。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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