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1.
灰色系统理论在水文地质工程地质中的应用   总被引:8,自引:1,他引:8  
GM(1,1)模型仅适用于服从指数规律的时间序列。在水文地质工程地质实践中形成的时间序列基本上不服从指数规律,因此不满足GM(1,1)模型应用的前提。  相似文献   

2.
灰色时序组合模型及其在矿井涌水量预测中的应用   总被引:6,自引:0,他引:6  
本文应用灰色系统GM(1,1)模型拟合数据序列的趋势项,时间序列分析ARMA(p,q)模型拟合数据序列的随机项,得到了一种新的组合模型。论述了这种模型的数学原理及建模步骤。应用组合模型建立了山东某矿井月涌水量动态模型,研究结果表明,该模型的预测精度高,适合于具有灰色特征的地质数据的模拟、控制和预测。  相似文献   

3.
斜坡蠕滑预报的相空间理论   总被引:3,自引:0,他引:3  
基于数据处理的组合方法(GMDH),由时间序列重构相空间,对相点进行数据组合处理,建立了斜坡蠕滑预报模型。实例分析表明,该模型具有较高地预报精度。  相似文献   

4.
祖厉河流域水沙时空分布及变化分析   总被引:2,自引:0,他引:2  
邓居礼 《水文》2001,21(2):47-50
应用水文站实测水沙资料序列,分区间分阶段统计分析了祖厉河流域的水沙时空分布特性及雨~水~沙关系,并对水沙量变化的影响因素进行了初步探讨,计算了各区间不同阶段的水沙变化量以及由于降雨影响和人类活动影响的水沙变化量所占的比重,对比分析了各区间水沙变化状况。结果表明,70年代后祖厉河流域年径流量、年输沙量明显衰减,主要是人类活动(水土保持和水利工程措施)影响造成的。  相似文献   

5.
祖厉河流域水砂时空分布及变化分析   总被引:2,自引:0,他引:2  
邓居礼 《水文》2001,21(2):47-50
应用水文站实测水沙资料序列,分区间分阶段统计分析了祖厅河流域的时空分布特性及雨-水-沙关系,并对水沙量变化的影响因素进行了初步探讨,计算了各区间不同阶段的水沙变化量以及由于降雨影响和人类活动影响的水沙变化量所占的比重,对比分析了各区间水沙变化状况,结果表明,70年代后祖厉河流域年径流量,年输沙量明显衰减,主要是人类活动(水土保持和水利工程措施)影响造成的。  相似文献   

6.
黄河中游区水沙时空分布及衰减分析   总被引:5,自引:1,他引:5  
陈小红  胡荣轩 《水文》1997,(1):19-23
对黄河中游区水沙序列进行了分阶段季节统计分析,对比研究了20多个流域的雨~水-沙关系,计算了各阶段水沙衰减量以及由于雨水衰减影响和水土保持工作影响的减沙量所占比重,对比分析了不同流域水沙变化状况,结果表明,80年代以来,绝大多数站年输沙量大幅度衰减,主要是水土保持(包括水利工程措施)发挥了作用。  相似文献   

7.
受气候系统影响的水文系统具有多时间尺度变化规律。由于平滩流量与水沙条件变化关系密切,也必然会呈现出多时间尺度演变规律。基于黄河下游主要测站1950~2007年平滩流量及水沙资料,利用小波分析原理分析了平滩流量、流量和含沙量序列的多时间尺度变化特征,以及不同时间尺度下水沙序列与平滩流量序列之间的相关关系。结果表明,黄河下游主要测站的平滩流量序列存在5~6年和19~20年的主要时间尺度,且水沙条件多尺度变化规律与平滩流量有密切关系。此外,对黄河上游和渭河支流主要测站的平滩流量与水沙条件的多时间尺度进行了分析,发现不同河段的平滩流量序列与含沙量序列存在不同的相位差,且相位差大小随含沙量增大而减少。揭示的黄河平滩流量与水沙条件的多时间尺度变化规律,可为研究河床演变的多时间尺度现象提供参考。  相似文献   

8.
地下水位,水质是受多种(水文、气象、地貌、地质、水文地质条件和人为活动)因素影响,其原始数据列表象复杂,离乱,但它必须蕴含某种内在规律性。关键是选择适当方法去发掘和利用它。一切灰色序列都能通过某种生成弱化其随机性,显现其规律。建立GM(1.1)模型采用均值生成和序列算子,对哈尔滨市江南地区地下水位,水质预测,结果较其它方法预测结果更接近实际,精度更高。  相似文献   

9.
崔建国  李文红 《地下水》1995,17(1):9-13,25
本文认为地下水多组分系统中各组分浓度的变化可用GM(1,1)模型描述,但其预测值必须满足溶液的电中性原理,因此,将溶液的电中性方程与GM(1,1)模型有机地结合起来建立了电中性条件下地下水水质灰色预测模型。  相似文献   

10.
杭州市城市垃圾量的灰色预测及其关联分析   总被引:2,自引:0,他引:2  
以杭州市历年生活垃圾排出量为参考序列,由人口变化、国民收入等因素组成5个比较数列,按灰色理论计算得关联系数、关联度和关联序,进而分析各因素之间随时间变化的动态关系及其特征。并以城市垃圾量的数据建立了GM(1,1)模型,预测杭州市垃圾排出量。结果表明,模型精度较高,预测值的验证性良好。我们认为环境水文地质方法可以在提高城市环境质量方面发挥良好的作用。  相似文献   

11.
Coastal margins, especially the river-influenced coastal areas, are considered as active interfaces between the continental and oceanic environments, which have huge dispersal of detrital materials and heavy metal input. It is well determined that the fine-grained sediments are important reservoir for the accumulation of heavy metals. In this study, we analyzed the radiocarbon age, texture, organic matter, carbonate content, and geochemical compositions of two sediment cores (GM42 and GM44) retrieved in front of the Coatzacoalcos River mouth basin, southwestern Gulf of Mexico (~864 and 845 m water depth, respectively). Our objective was to infer the sedimentation rate, intensity of weathering, provenance, and influence of anthropogenic activities on heavy metal contamination in sediments. The radiocarbon-age measurements of mixed planktonic foraminifera for core GM44 reveals an age of 21,289 ± 136 cal. years B.P., which fall within the Late Glacial Maximum (LGM; 21000 ± 2000 years B.P). The calculated sedimentation rate for core GM42 (~0.013 cm/year) is lower than in core GM44 (0.022 cm/year), which is probably due to the variations in detrital sediment input and/or seafloor topography. The weathering indices such as chemical index of alteration (CIA), chemical index of weathering (CIW), and plagioclase index of alteration (PIA) suggested that the source area experienced low to moderate intensity of chemical weathering under warm to humid climatic conditions. The SiO2/Al2O3, Al2O3/Na2O, and K2O/Al2O3 ratio values indicated moderate to high compositional maturity. The major and trace element concentrations suggested that the sediments were likely derived from intermediate source rocks. The heavy metal contents indicated that the sediments were not contaminated by the industrial waste disposals supplied by the Coatzacoalcos River. The redox proxy sensitive elements such as V, Cr, Cu, and Zn indicated an oxic depositional environment for the deep-sea sediment cores. The application of discrimination diagrams for the geochemistry data revealed a passive margin setting for the sediment cores. The compositional variations observed at the upper sections (<30 cm) between the two sediment cores revealed that the type of detrital sediments supplied by the Coatzacoalcos River to the deep sea area is not uniform, which is also revealed by the variation in sedimentation rate.  相似文献   

12.
多沙河流平面二维泥沙数学模型研究   总被引:3,自引:0,他引:3       下载免费PDF全文
针对冲积河流河床演变速度快、边界调整幅度大的特点,采用积分方法数值求解水流泥沙基本方程,建立了适合于多沙河流泥沙及河床演变规律的二维数学模型,在数值方法方面考虑了物质守恒性及对多变边界的适应性,采用了比较简单的动边界处理模式。通过工程实例的计算验证,证实了模型所采用的基本方法是合理的,模型有较强的河床边界适应能力,可用以解决有关多沙河流河床演变预测及浑水洪水预报的有关问题。  相似文献   

13.
黄河下游河槽萎缩与水沙条件关系初步分析   总被引:4,自引:0,他引:4  
陈界仁  夏爱平 《水文》2002,22(6):19-21,15
根据黄河下游实测资料分析河槽萎缩变化,采用断面过水面积、同流量(Q=3000m3/s)水位作为河槽萎缩指标,利用水沙系数(平均含沙量与平均流量比值)反映水沙条件变化,建立了河槽萎缩指标与水沙系数的关系,表明河槽萎缩指标与水沙系数有一定的变化规律。  相似文献   

14.
黄河头道拐水沙变化多元驱动因子贡献率分析   总被引:1,自引:0,他引:1       下载免费PDF全文
根据1950—2010年水沙实测资料,采用统计分析方法,通过构建非线性响应模型,辨识了水沙变化主导驱动因子,定量评估了多因子对黄河上游头道拐水沙变化的贡献率.结果表明:头道拐1950—2010年多年平均径流量减少速率为2.23亿m3/a,多年平均输沙量减少速率为0.027亿t/a,1987—2010年径流泥沙减少趋势更为明显,同期输沙量减幅明显大于径流量减幅;1969—2010年气候因子和下垫面因子对头道拐站年径流模数和年输沙模数变化的贡献率均约为2:8,下垫面因子明显占主导地位,其中宁蒙灌区年引水量对年径流模数变化的贡献率最大,达到42%,龙羊峡和刘家峡等水库运用对年输沙模数变化的贡献率最大,达到34%.预计今后兰州以上径流变化和兰州至头道拐区间主要支流来沙变化两大自然因素将是头道拐水沙变化的主导因子;灌区引水和支流水土保持综合治理减沙对头道拐水沙变化的贡献率将居主导地位.  相似文献   

15.
JAMES P. MAY 《Sedimentology》1973,20(2):203-211
A model to account for the occurrence of heavy mineral concentrations as discrete lamina on beaches is presented. The model is based on the shoreward variation in the distribution of bottom fluid velocities due to shoaling, progressive, gravity, water waves. This variation causes certain portions of the sediment population to be transported shoreward at a faster rate than other portions. On moderate energy shorelines composed of sand-sized sediment the selectively transported portion may include the relatively hard-to-move heavy mineral fraction. Wave tank experiments with artificially prepared sediment populations provide empirical support for the proposed model. Under certain wave conditions it was found that the heavy mineral fraction of the sediment population moved shoreward at a faster rate than did the light mineral fraction.  相似文献   

16.
A hydrologic regression sediment-yield model was established to determine the relationship between water discharge and suspended sediment discharge at the Blue Nile and the Atbara River outlet stations during the flood season. The model consisted of two main submodels: (1) a suspended sediment discharge model, which was used to determine suspended sediment discharge for each basin outlet; and (2) a sediment rating model, which related water discharge and suspended sediment discharge for each outlet station. Due to the absence of suspended sediment concentration measurements at or near the outlet stations, a minimum norm solution, which is based on the minimization of the unknowns rather than the residuals, was used to determine the suspended sediment discharges at the stations. In addition, the sediment rating submodel was regressed by using an observation equations procedure. Verification analyses on the model were carried out and the mean percentage errors were found to be +12.59 and –12.39, respectively, for the Blue Nile and Atbara. The hydrologic regression model was found to be most sensitive to the relative weight matrix, moderately sensitive to the mean water discharge ratio, and slightly sensitive to the concentration variation along the River Nile's course.  相似文献   

17.
王涛  刘雷 《陕西地质》2012,30(1):60-64
采用灰色系统理论中灰色动态模型GM(1,1),对一观测孔地下水位埋深进行灰色动态模拟。利用观测孔2011年实测地下水位埋深数据建立GM(1,1)预测模型,并对2012年地下水位埋深进行预测。经验证,模型预测精度较高,具有一定的实用价值。  相似文献   

18.
介绍了灰色GM (1,1)模型基本原理及建模程序,列举了该模型应用于金矿床深部定量成矿预测研究的3个具体实例,通过对预测结果的综合对比分析,认为矿体自身变化程度及模型本身单调性函数特征是影响预测精度的主要因素,提出了矿体变化程度及规律研究是有效应用GM (1,1)模型进行成功预测的前提和基础.  相似文献   

19.
Regulatory authorities require estimates of ambient background concentrations (ABCs) of potentially harmful elements (PHEs) in topsoil; such data are currently not available in many countries. High resolution soil geochemical data exist for only part of England and Wales, whilst stream sediment data cover the entire landscape. A novel methodology is presented for estimating soil equivalent ABCs for PHEs from high-resolution (HR) stream sediment geochemical data grouped by common parent materials (PM), using arsenic (As) as an example. Geometric mean (GM) values for local PM groups are used to investigate different approaches for transforming sediment to soil equivalent concentrations. Holdout validation is used to assess: (i) the optimum number of samples for calculating local GM values, and (ii) the optimum scale at which to group data when using linear regression analysis to estimate GM soil ABCs from local sediment geochemical values. Holdout validation showed that the smallest differences were generally observed when five observations were used to calculate the GM and that these should be grouped over the smallest possible area in order to encompass soils over PMs with elevated GM As concentrations. Geometric mean ABCs are estimated and mapped for As in mineral soil across all of England and Wales within delineations of PM polygons. Errors for the estimation of soil equivalent GM As ABCs based on sediment data for an independent validation set were of a similar magnitude to those from holdout validation applied to the original data suggesting the approach is robust. The estimates of soil equivalent ABCs suggest that As exceeds the regulatory threshold used in risk assessments for residential land use (20 mg kg−1) across 16% of the landscape of England and Wales. The applicability of the method for cognate landscapes, and potential refinements is discussed.  相似文献   

20.
白涛  慕鹏飞  张明 《水科学进展》1990,31(2):194-202
黄河是世界上含沙量最高的河流,其上游沙漠宽谷河段的冲沙输沙效应受来水来沙和地形条件变化等影响。为研究高含沙河流在低温条件下的输沙效应,通过引入水温因子,建立了黄河上游沙漠宽谷河段巴彦高勒站的输沙率模型。基于First Optimization平台的通用全局优化算法率定参数,验证了输沙率模型,量化了高含沙河流的低温输沙效应。结果表明:① 水温越低(1~7 ℃),河道输沙率越大,表明水温对河道输沙率的影响主要表现在低水温时期;② 任意一种工况下,水温1 ℃时河道输沙率约为25 ℃时的2.5倍;③ 低水温(5 ℃)较常温(16.6 ℃)下的河道输沙率提高了40.7%,在黄河上游开河低温期进行大流量冲沙输沙是水沙调控的最佳时机。研究成果以期为黄河上游沙漠宽谷河段低水温高效冲沙输沙和其他寒区高含沙河流的治理提供技术支撑。  相似文献   

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