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鄱阳湖流域水土流失加剧了洪涝灾害。治理水土流失能增强山丘地涵养水源的能力,削洪减沙,减少库容损失,降低河床,具有明显的防洪效益。进行流域防洪规划时,应将防治水土流失与防洪治涝结合起来,因地制宣,综合治理。 相似文献
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年最大洪峰流量预测,受较多的复杂因素的影响,不确定性较强,用常规统计方法做出准确预报具有较大困难。从水文序列本身出发,提出将投影回归模型应用于年最大洪峰流量预测,为了更好获得投影寻踪模型参数和预测精度,提出了运用延迟相关系数法确定回归预测因子、群居蜘蛛算法优化投影寻踪模型最佳投影方向参数a、利用最小二乘法确定多项式的权系数c、岭函数个数M的群居蜘蛛优化投影寻踪年最大洪峰流量预测模型,结合长江宜昌站(1882年-2004年)的年最大洪峰流量资料进行实例预测,训练阶段平均绝对相对误差为8.61%,预测阶段平均绝对相对误差为10.51%,该模型预测效果较好,模型结果稳定,可有效应用于年最大洪峰流量预测。 相似文献
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Many modeled and observed data are in coarse resolution, which are required to be downscaled. This study develops a probabilistic method to downscale 3-hourly runoff to hourly resolution. Hourly data recorded at the Poldokhtar Stream gauge (Karkheh River basin, Iran) during flood events (2009–2019) are divided into two groups including calibration and validation. Statistical tests including Chi-Square and Kolmogorov–Smirnov test indicate that the Burr distribution is proper distribution functions for rising and falling limbs of the floods’ hydrograph in calibration (2009–2013). A conditional ascending/descending random sampling from the constructed distributions on rising/falling limb is applied to produce hourly runoff. The hourly-downscaled runoff is rescaled based on observation to adjust mean three-hourly data. To evaluate the efficiency of the developed method, statistical measures including root mean square error, Nash–Sutcliffe efficiency, Kolmogorov-Smirnov, and correlation are used to assess the performance of the downscaling method not only in calibration but also in validation (2014–2019). Results show that the hourly downscaled runoff is in close agreement with observations in both calibration and validation periods. In addition, cumulative distribution functions of the downscaled runoff closely follow the observed ones in rising and falling limb in two periods. Although the performance of many statistical downscaling methods decreases in extreme values, the developed model performs well at different quantiles (less and more frequent values). This developed method that can properly downscale other hydroclimatological variables at any time and location is useful to provide high-resolution inputs to drive other models. Furthermore, high-resolution data are required for valid and reliable analysis, risk assessment, and management plans. 相似文献
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World oil depletion, including natural gas liquids, was modelled in the past by many authors. Recently, Guseo and Dalla Valle have introduced and Guidolin has applied a new approach following perturbed life-cycle diffusion models. Here we examine joint effects of economic and strategic or technological interventions using a Generalized Bass Model (GBM). Statistical analysis takes into account three different hierarchical levels: natural diffusion, long memory interventions and stochastic components. The main results confirm the statistical significance of historical 1970s shocks and highlight a strong long memory effect due to an increase in oil production after World War II. The estimated peak-date, 2007, and the 90% depletion time, 2019, are determined under an equilibrium intervention hypothesis. 相似文献
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Evaluating flood risk management options in Scotland: A participant-led multi-criteria approach 总被引:1,自引:0,他引:1
Wendy Kenyon 《Ecological Economics》2007,64(1):70-81
The characteristics of flood risk management include complexity, large spatial scales, inter-temporal issues, plural values and conflicts of interests. It is argued that issues with such characteristics require public participation in the decision making process. This study builds on existing deliberative processes to develop a new participant-led multi-criteria method to evaluate flood risk management options in Scotland. The results show that participants preferred regeneration or planting of native woodland to other flood management options, and least preferred building flood walls and embankments. The design of the workshops allowed a rich dataset to reveal the thinking behind such results and provided a deeper understanding of why participants came to these conclusions. 相似文献
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通过对乡(镇)水管站的现状进行分析,总结了基层水利队伍建设存在的问题,提出了加强基层水利队伍建设的建议. 相似文献