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1.
针对多属性决策结果的多值型和模糊性,结合蒙特卡罗模拟方法、加权优序法、优先等级排序法,提出了一种解决O-O型决策问题的综合评价方法,该方法内生权重,然后分别基于离开流、进入流和净流对方案排序,并将各排序进行有机集成,得到最终评价结果。  相似文献   

2.
动态综合评价的二次加权法   总被引:10,自引:2,他引:10  
针对一类特殊的多指标决策问题一动态综合评价(或排序)问题,提出了一种基于二次加权平均的新的动态排序方法.这种方法具有原理简单、易懂、易操作、计算量小等特点.  相似文献   

3.
在广泛调查研究的基础上,提出了并购目标企业的遴选综合评价指标体系,利用主成分法建立了综合评价模型,并结合实际案例进行了分析,结果证明了评价指标体系和遴选评价模型的可行性,并通过建模计算,对多个并购目标进行排序,为我国正处发展期的企业并购活动提供了一种可行的、便于辅助买方企业决策的并购目标遴选综合评价方法。  相似文献   

4.
 为克服岩体质量分级中确定评价指标权重系数带有专家打分的主观偏向性,利用熵理论客观地确定岩体质量分级评价指标的熵权系数,结合属性识别理论,建立岩体质量分级判别的属性识别模型。模型选取岩石单轴抗压强度、RQD 值、结构面间距、结构面摩擦系数、岩体钻进速度和岩体声波速度6 个参数作为岩体质量分级综合评价指标,以三山岛金矿7 个采场为研究背景,建立岩体质量分级的属性识别模型,根据信息熵理论计算各评判指标的权重,计算各指标属性测度,利用置信度准则和评分准则,预测岩体质量排序和等级。研究结果表明,属性识别结果较RMR 法更准确,评价结果客观、可信。  相似文献   

5.
利用一种改进了的主成分分析综合评价法 ,通过Mathematica软件计算 ,对我国十二个湖泊富营养化污染状况作了评价排序 ,给出了排序结果 ,与常规方法的排序结果进行了比较。主成分分析法应用的关键在于确定各项指标的权重  相似文献   

6.
针对城市竞争力评价中存在的单一方法评价结果不一致的问题,对黑龙江省12个主要城市的11项指标,分别采用综合指数法、层次分析法、主成分分析法和因子分析法进行综合评价和排位;再以Spearman等级相关系数为检验标准,利用平均值法、Board法、Copealand法、模糊Board法对单一模型进行组合,反复迭代,得到黑龙江省各主要城市综合竞争力的综合评价和排序。  相似文献   

7.
提出了一种将TOPSIS法和AHP法进行融合的综合评价方法。即运用AHP法确定评价指标的权重 ;运用TOPSIS法进行评价指标值的规范化和排序计算。此方法将AHP法和TOPSIS法进行了有效的融和 ,使评价方法的应用领域更加广泛 ,同时提高了评价方法的易操作性和评价结果的客观性和准确性  相似文献   

8.
为了准确地对中巴公路沿线泥石流进行易发性评价,针对评价过程中存在随机性和模糊性的问题,文章建立了基于正态云的泥石流易发性评价模型。该模型首先根据勘察规范选取了14个评价指标,并基于易发性分级标准生成每个指标隶属于不同等级的数字特征,然后利用正向正态云发生器模拟实测样本值隶属于各等级的确定度,结合评价指标权重得到评价样本的综合确定度,最后按照最大确定度原则选择泥石流易发性等级。将中巴公路沿线泥石流易发性等级评价实例结果与采用其他评价方法所得结果进行对比,结果表明,该模型应用于泥石流易发性评价是合理可行的,且该模型概念清晰、计算简便,为类似不确定性问题的处理提供了一种新的参考。  相似文献   

9.
针对农业园区综合能源系统评价中采用单一评价法造成主观意识强,结果不全面的问题,提出了一种基于组合赋权T-M(TOPSIS-MEE)模型农业园区综合能源系统评价的方法。首先根据农业园区综合能源系统架构建立了包括经济性、技术性、环保性3个一级指标和14个二级指标的指标体系,并通过改进的AHP-CRITIC 组合法分别对主、客观性指标赋权,采用最小鉴别信息原理得到各指标综合权重,避免单一赋权的缺陷。其次,通过物元可拓模型(MEE)优化了优劣解距离法(TOPSIS),提升了方法的适用性,并对评价方案进行等级判定和排序。最后以某农业园区的3种规划方案为实例进行验证,结果表明3种方案特征值分别为3.1224、3.2436、3.4233,相较于未优化前的结果方案1、2有明显的等级区分,因此所提方法能够对农业园区综合能源系统科学有效的评价,评价结果符合实际,可信度高。  相似文献   

10.
公路隧道岩体质量分级的模糊层次分析法   总被引:5,自引:0,他引:5  
建立公路隧道岩体质量分级的模糊层次分析法(AHP),对影响公路隧道岩体质量分级的各因素进行分析和调整,建立层次关系,构造阶层结构;采用模糊理论建立正倒值矩阵,计算各因素权重,建立各因素评分准则,根据专家调查与力学试验等方式确定各因素得分,采用逻辑运算计算综合评分,进而评判隧道岩体级别;给出模糊层次分析法算法流程,应用于常德一张家界高速公路关口垭隧道(44个试验断面),将评判结果与传统的RMR岩体分级结果进行对比分析。研究结果表明,采用本方法进行岩体分级,43个断面与开挖实际情况吻合,而采用RMR方法仅36个断面接近实际情况;公路隧道岩体质量分级的模糊AHP法克服了传统方法固定评价因素和固定评分方式的缺陷,可以动态地选取评价因素,减少评分的主观性,评价结果更接近工程实际,为隧道、地下工程、边坡等的岩体质量分级研究提供了一种新的思路。  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.
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   

13.
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   

14.
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   

15.
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   

16.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

17.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

18.
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   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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