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1.
基于多源信息融合理论,结合安全监测数据及滑坡变形破坏特征,构建完善的滑坡安全性评价体系,应用云模型生成各评价指标隶属度,采用引入权重系数的改进D-S证据理论进行数据融合分析,建立一种基于云模型和改进D-S证据理论的滑坡安全性多指标综合评价模型,以实现对滑坡安全性的综合评判。以雅砻江卡拉水电站周家滑坡安全评价分析为实例进行研究,按最大隶属度原则判定周家滑坡的安全状态,分析表明其整体处于基本稳定状态,B1区处于不稳定状态,与实际基本相符。  相似文献   

2.
利用模糊数学综合评判模型对涉铝企业环境风险中对环境污染事故有影响的因子建立评判模型.在该模型中,就涉铅企业环境风险固有风险性评判的评价指标选取,评价等级划分以及权重的确定等进行确定研究.  相似文献   

3.
利用云模型能够处理各种不确定性问题的特点,构建基于云模型的重金属健康风险评价模型.将评价标准分为六个风险等级,分别选取Fe、Mn、Cu、Cr、Cd、As和Pb作为评价因子,将构建好的风险评价模型应用于某饮用水源地原水的重金属评价.评价结果表明,该水源地的成人重金属风险值为Ⅳ级,存在一定风险;基于云模型的评价方法不仅能够确定风险等级,还能更全面地反映同级别重金属危害程度的高低;通过与基于区间数理论的评价结果对比发现,云模型通过确定度来确定最终风险等级,验证了该方法的适用性;另外该方法的可视性强,结合云图,可以较为直观地了解当前风险大小.  相似文献   

4.
膨胀土与石灰改良膨胀土胀缩性的云模型评价   总被引:1,自引:0,他引:1  
为解决胀缩性评价过程中模糊指标与随机指标统一处理及定性定量转化问题,探讨了基于云模型理论的胀缩性评价模型.首先基于胀缩性分类标准生成每个评价指标在不同等级的云数字特征,并应用正向正态云发生器模拟实测样本指标值隶属于各等级的确定度,然后结合指标权重获得综合确定度,以最大综合确定度值判定样本的胀缩性等级.最后基于合肥新桥国际机场膨胀土地基处理工程实例来验证该模型的可靠性,并与集对分析、可变模糊集方法和模糊数学方法的判别结果进行了对比分析.结果表明,基于云模型评价膨胀土和改良土胀缩性等级是有效可行的,且预测结果可充分反映现场实际情况.  相似文献   

5.
基于风险理论,利用模糊数学方法,建立堰塞湖风险等级评价模型.该模型考虑堰塞体物质组成、堰塞体高度、库容、已有蓄水量以及风险人口、国民经济等6项风险指标,能够直观、快速地确定单座堰塞湖的风险等级,特别是对未蓄满库的堰塞湖有较好的适用性.以徐家坝堰塞湖为例,通过构造隶属函数确定评判矩阵R,根据改进的层次分析法确定各评价指标的权重集A,再由A和R线性变换得到综合决策向量B,最后根据最大隶属度原则确定堰塞湖的风险等级.  相似文献   

6.
针对影响煤矿采掘工作面瓦斯突出因素的不确定性和复杂的非线性关系,在分析Dempster-Shafer(D-S)证据理论的基础上,提出瓦斯突出危险等级评判的多传感器数据融合方法;通过对传感器采集的待评判采掘面参数进行预处理,得出D-S证据理论各传感器对突出危险等级的信度函数分配,再利用D-S证据理论的合成规则得到融合后的信度函数分配,从而实现危险等级的评判。结果表明,该方法具有良好的适应性并能得到较高的精确度,在一定程度上提高了评判系统的性能。  相似文献   

7.
为研究车辆运行风险等级,通过模糊集理论和DS证据融合算法,研究不同因素在不同风险等级的概率隶属值,运用层次分析法计算不同因素对车辆运行风险系统的权重值,通过加权计算车辆运行综合因素发生不同等级风险的概率和综合风险值。通过对湖南省高速公路某一路段作为实例分析,研究表明:该路段整体车辆运行风险是中等等级风险。因此,模糊集-DS证据理论-AHP的方法对车辆运行风险评估是行之有效的。  相似文献   

8.
针对影响煤矿瓦斯突出因素的不确定性和复杂的非线性关系,不能够利用经典的数学理论建立精确的预测模型,将模糊神经网络和D-S证据理论有机结合,提出了基于模糊神经网络和D-S证据理论的煤矿瓦斯突出危险等级评判策略.首先对传感器采集的待评判采掘面参数进行预处理,使用模糊神经网络得出第一步的融合结果,并将其进行归一化处理,归一化函数作为基本概率赋值函数,然后将归一化之后的数值作为基本概率分配值,再用D-S证据理论进行第二次数据融合,作出最终评判.实验结果表明,该方法具有良好的适应性并能得到准确性较高的评判结果.  相似文献   

9.
文章针对军机研制过程中不确定性因素多、风险大的问题,根据"证据折扣"思想,提出了一种基于区间直觉模糊和改进D-S证据理论的风险评估方法。首先,构建了军机研制风险评估指标体系,提出了基于指标不确信度的Mass函数构建方法;然后,提出了基于区间直觉模糊熵的指标权重确定方法,将各要素的指标集关于评语集的评估证据进行修正与合成;最后,提出了融合冲突系数和Jousselme距离的证据冲突度计算方法并以此度量要素权重,将各要素关于评语集的评估证据进行修正与合成,确定了风险等级。算例结果验证了方法的可行性和有效性。  相似文献   

10.
在对路段安全状态和山区高速公路进行定义的前提下,提出了山区高速公路路段的定义及其安全状态评价指标及评价标准.通过在需要进行评价的路段以及路段的上游安装交通流信息采集设备来获取速度参数.以山区高速公路交通事故历史数据和实时的速度参数作为评价指标,参考提出的评价标准,建立了基于概率神经网络(PNN)的路段安全状态评价模型....  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 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   

13.
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   

14.
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   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
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   

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