漓江最高水位的分析及预测

通过对漓江水位的分布特征分析得出：漓江水位不仅与降水量、降水强度、降水时空分布有关系，还与前期早涝情况及蓄水程度有关；漓江水位的年际变化与桂林市雨量的年际变化一致，大致以10a为周期。然后采用双向差分建立了最高水位的预测模型，以预报量的前差和后差预报误差之和趋于最小时求出模型的参数，并对2002～2005年的最高水位进行了预报，结果表明该模型在最高水位预测中具有较好的应用价值。     

Forecasting annual precipitation to improve the operation of dams in the Comahue region,Argentina

ABSTRACT

This paper attempts to design statistical models to forecast annual precipitation in the Neuquen and Limay river basins in the Comahue region of Argentina. These forecasts are especially useful as they are used to better organize the operation of hydro-electric dams, the agriculture in irrigated valleys and the safety of the population. In this work, multiple linear regression statistical models are built to forecast mean annual rainfall over the two river basins. Since the maximum precipitation occurs in the winter (June–August), forecasting models have been developed for the beginning of March and for the beginning of June, just before the rainy season starts. The results show that the sea-surface temperatures of the Indian and Pacific oceans are good predictors for March models and explain 42.8% of the precipitation index variance. The efficiency of the models increases in June, adding more predictors related to the autumn circulation.     

基于改进遗传算法的Holt-Winters模型在采空沉陷预测中的应用

针对遗传算法存在的缺陷,提出了用小生境方法改进遗传算法。为了提高采空沉陷预测精度,借助Holt-Winters模型的预测功能,应用改进遗传算法求解和优化Holt-Winters模型组合参数,形成了改进遗传算法-Holt-Winters模型组合算法。将组合算法应用于长平高速公路采空区路段沉陷预测,计算表明：改进遗传算法弥补了传统遗传算法易早熟、局部寻优能力弱的缺陷;改进遗传算法-Holt-Winters模型组合算法克服了按梯度试算法搜索质量差和精度不高的缺点,输出稳定性好,预测结果相对误差在2%以内,预测精度显著提高;在采空沉陷中长期预测的相对误差小于0.79%,该算法可用于中长期采空沉陷预测。     

红外云顶亮温在西北太平洋热带气旋强度预报中的应用

应用GMS-5气象卫星红外云顶亮温(TBB)资料,分析西北太平洋的热带气旋(TC)TBB、TBB的对称和非对称分量与滞后0-48 h TC强度的相关关系.发现,TC眼墙附近东南侧的TBB、距TC中心半径0.8°-1.7°范围内TBB对称分量和1-10波振幅之和与0-48 h的TC强度有很好的负相关关系,与滞后24 h的TC强度相关极值分别达到-0.52,-0.59和-0.625.考虑气候持续因子、天气因子及TBB因子,针对1996-2002年西北太平洋远海区域(0°-50°N,120°-155°E)热带风暴(TS)等级以上样本,建立12,24 h和48 h强度预报方程并进行独立样本检验.结果表明,1.0°-1.5°环域平均的TBB对12 h强度预报的方差贡献位居第4,TC东南侧TBB的平均值和1.1°-1.5°范围TBB极大与极小值之差对24 h强度预报的方差贡献分列第3和第5位.考虑TBB因子的回归方程对TS和强热带风暴(STS)的强度预报能力有较大提高,对12 h内强度减弱15 m/s以上TC的12 h预报、强度稳定TC的24 h预报和强度48 h增强10 m/s 以上TC的48 h预报均有所改善.     

信息数字化在地震预测中的应用研究

鉴于地震是变化事件而展示信息变化的过程性,本工作对＂5.12＂汶川8.0级地震和2011年3月23日茂县4.0级地震相继按地热的变化信息和＂时序性＂变化信息进行了数字化分析。分析结果表明,应用此方法展示了地震前后信息变化的过程性（演变）的特征（差异性）,为改善地震预测或预防提供了一种方法,同时＂地热＂可以作为地震分析、...     

自适应过滤法及其在大坝监测中的应用

介绍了自适应过滤法原理及计算方法,利用自适应过滤法模型预测了大坝变形趋势。实际数据计算结果表明:自适应过滤模型预测精度优于传统的回归分析法,在大坝监测预报中是有效可行的。     

Instability of sand–silt mixtures

The instability of the sand–silt mixtures with different amount of fines contents were studied in this paper. It showed that the slope of the instability lines increases with the increasing relative densities, and it approaches the slope of the failure line (steady state line) at a high relative density. The relationship between the peak stress ratio and the intergranular void ratio can be described by a common curve for all the mixtures with fines contents less than the transitional fines content. There may also exist a unique curve for the relationship between the peak stress ratio and interfine void ratio for the mixtures with fines contents higher than the transitional fines content. If the yield strength ratio is used instead of the peak stress ratio, the relationships can be characterized in the same way.     

Predictable and Unpredictable Components of the Summer East Asia–Pacific Teleconnection Pattern

The East Asia–Pacific(EAP) teleconnection pattern is the dominant mode of circulation variability during boreal summer over the western North Pacific and East Asia, extending from the tropics to high latitudes. However, much of this pattern is absent in multi-model ensemble mean forecasts, characterized by very weak circulation anomalies in the mid and high latitudes. This study focuses on the absence of the EAP pattern in the extratropics, using state-of-the-art coupled seasonal forecast systems. The results indicate that the extratropical circulation is much less predictable, and lies in the large spread among different ensemble members, implying a large contribution from atmospheric internal variability. However,the tropical–mid-latitude teleconnections are also relatively weaker in models than observations, which also contributes to the failure of prediction of the extratropical circulation. Further results indicate that the extratropical EAP pattern varies closely with the anomalous surface temperatures in eastern Russia, which also show low predictability. This unpredictable circulation–surface temperature connection associated with the EAP pattern can also modulate the East Asian rainband.     

基于短时强降水概率预报的模糊检验试验

利用短时强降水概率预报模型生成短时强降水(≥20mm/h)概率预报产品,并对其进行“点对面”模糊检验试验。结果表明：短时强降水(≥20mm/h)概率预报和SWC_WARMS模式最大小时雨量(≥20mm/h)的“点对面”TS评分均明显高于相应的“点对点”评分,短时强降水(≥20mm/h)预报结果可在30～40km范围内进行调整;短时强降水(≥20mm/h)概率预报在概率为30%时TS评分达到最大,Bias接近为1,预报偏差最小;短时强降水(≥20mm/h)概率预报比SWC_WARMS模式最大小时雨量(≥20mm/h)预报更具有参考价值。     

浙江登陆台风的灰色灾变预测研究

根据热带气旋在浙江登陆的基本资料, 利用灰色灾变预测的原理和方法, 对台风登陆浙江的年份进行了预测研究。结果表明, 浙江未来第一、第二和第三个强台风登陆年将分别出现在2001、2004 和2008 年