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1.
用准周期(PP)方法预测地震序列中早期强余震   总被引:1,自引:0,他引:1  
研究了地震序列的准周期性,提出了预测早期强余震发生时间的准周期方法及其定量预报指标,同时进行了回溯性预报检验,R值评分为0.45。表明该方法具有一定的预报效能。  相似文献   

2.
应用“九五”子专题“地下水物理参量异常识别标志体系及预报方法研究”的研究思路,预报方法和指标对河北省井网1983年以来的水位观测资料进行了全时程扫描,结果表明“群井群常年频次法”在河北及邻近地区中强地震前有较明显的异常显示,应用效果较好,对该方法进行了预报效能R值评分,评价结果表明漏报率低,虚报率高。  相似文献   

3.
应用“七五”、“八五”攻关确定的6种分析方法并运用2种新方法,对天山地区10个测点的定点为资料进行全时空扫描,归纳出天山地震带Ms≥5.0地震的异常特征,获得了各种方法地震三要素的异常识别指标,并对各项结果从物理意义和统计角度进行相关分析,应用R值、V值评分法对各种方法的预报效能进行了统一评价,最后总结出天山地区1年尺度的地震地形变前兆识别方法和指标体系。  相似文献   

4.
琼中地磁台以磁报震方法探索   总被引:1,自引:1,他引:0  
胡久常 《华南地震》1994,14(3):61-65
通过对海南低纬度地区地磁场垂直分量的特殊变化与海南岛及其邻近地区地震活动的对比分析,并结合实用化攻关成果,总结出一套利用琼中地磁台垂直分量11年变化周期、相关系数R值变化曲线和日变化“双低点”异常预报海南岛及其邻近地区地震活动的方法。  相似文献   

5.
于建军  罗兰格 《中国地震》2000,16(3):223-232
在对地震异常光信息量先前研究的基础上,进一步给出了描述各种地震异常前光信息量的普适性综合数学表达式,从大量震例资料入手,再次研究了地震异常延续有效性的问题,进而建立了地震异常持续有效的有效时间与有延续有效时间的数学关系式。收储整理了1980~1997年华北地区水化、形主为、地磁、应力、水位、地电等371个观测项目、上百万个前兆观测数据,对每一项观测项目逐一计算了它们的地震异常前光信息量,研究了华北地区近20年的地震异常前光信息场的演化特征及其与地震的关系,建立了华北地区Ms≥地震的中短期综合预报指标体系,经R值评分检验,表明该地震综合预报指标体系在中短期地震预测中具有一定效果。  相似文献   

6.
苏乃秦  王桂岭 《内陆地震》1995,9(2):132-136
应用吉尔吉斯斯坦地震研究所介绍的空区参数法,对新疆天山地区进行分时空扫描计算和R值评分检验,筛选出有一定预报效能的10个小区,确定了异常判据和预测规则。1993年10月,根据A1、A2小区出现的空区参数异常,对1993年12月1日疏附6.0级地震作出预报,预报三要互完全正确。  相似文献   

7.
在北天山地震带,利用区域台网Ms2.8—4.9级地震观测结果计算断层总面积∑(t)值,并根此预报附近地区的5级以上地震。结果表明,在16年研究时段内,共出现9次异常,它们分别与其后短期内发生的8组(共14次)5次以上地震相对应。统计评分R值为0.47,说明方法含有一定地震信息,具有中短期预报效能。  相似文献   

8.
应用“九五”子专题“水化学参量异常识别标志体系及预报方法研究”的研究思路、预报方法对河北省及邻区1983年以来的水氡观测资料进行了全时程扫描.在预报指标的使用过程中,根据本省的水氡资料特征作了适当调整.结果表明,“中期、短期异常预报跟踪方法”在河北及邻近地区中强地震前有较好的预报效果,预报效能R值评分结果表明,70%以上井孔的水氡资料通过R值检验,具有监测预报能力.  相似文献   

9.
郭德科  赵卫红 《内陆地震》2002,16(4):331-336
利用地震活动群集度指标 CV值对华北地区 1 6次中强地震前 CV值与地震活动的关系进行了分析和研究 ,发现在中强震前 1— 3年 CV 值显示高值异常。把 CV值的这种特征应用于河南及其邻区 ML≥ 5.0地震的预报研究中 ,再根据制定的预报规则 ,进行预测内符检验和预报评分。结果表明 ,该方法是一种有效的中期地震预报方法 ,具有推广应用价值。  相似文献   

10.
“诱发前震”预测效能评价   总被引:1,自引:0,他引:1  
“诱发前震”现象在区域地震活动中较普遍,据此提出A-F-B图象预报方法,以区域大震后短时间内发生的小震为预报因子,判断以后大震的位置并推测其震级与时间。为了检验该方法的实用性,统计了我国西南地区1970—1983年和华北地区1966—1984年的地震资料,对其预测效能做了统计评价。评分采用W值与R值。其中:W=1-(漏报率+虚报率);R=报对地震占有面积/应预报地震占有面积-预报区占有面积/研究区总面积。结果为W与R值都大于0.5,波动在0.5~0.8之间;并计算出各种不同预报参量的频数概率分布,给出了单次预报在取不同空间与时间范围的信度。  相似文献   

11.
The researches on the assessment of earthquake forecast are reviewed, then the R-value assessment is further developed theoretically in the paper. The results include the arithmetic of the R-values of earthquake occurrence under the condition that “anomaly“ occurred or no “anomaly“ occurred respectively, and the relation between the values. The distribution of Rvalue of a forecast method, corresponding to multi-status anomalies being independent each other, is also developed in the paper. The appropriate methods to estimate the R-values and extrapolate the occurrence probability of future earthquakes are also given in the paper.  相似文献   

12.
13.
BMA集合预报在淮河流域应用及参数规律初探   总被引:1,自引:1,他引:0  
以淮河流域吴家渡水文站作为试验站点,采用基于贝叶斯平均法(BMA)的集合预报模型处理来源于马斯京根法、一维水动力学方法、BPNN(Back Propagation Neural Network)的预报流量序列,通过分析BMA的参数以及其预报结果,对各方法在淮河典型站点流量预报中的适用性进行验证与分析.经2003—2016年19场洪水模拟检验可知,BMA模型能够有效避免模型选择带来的洪水预报误差放大效应,可以提供高精度、鲁棒性强的洪水预报结果.通过进一步比较各模型统计最优的频率与BMA权重值之间的相关性,发现权重值不适用于对单场洪水预报精度评定,而适用于描述多场洪水预报中,模型为最优的统计频率;基于大量先验信息,提前获取BMA的权重等参数,将是指导模型选择、降低洪水预报不确定性、改进洪水预报技术的有效手段.  相似文献   

14.
Effect of streamflow forecast uncertainty on real-time reservoir operation   总被引:1,自引:0,他引:1  
Various hydrological forecast products have been applied to real-time reservoir operation, including deterministic streamflow forecast (DSF), DSF-based probabilistic streamflow forecast (pseudo-PSF, pPSF), and ensemble or probabilistic streamflow forecast (denoted as real-PSF, rPSF). DSF represents forecast uncertainty in the form of deterministic forecast errors, pPSF a conditional distribution of forecast uncertainty for a given DSF, and rPSF a probabilistic uncertainty distribution. Compared to previous studies that treat the forecast products as ad hoc inputs for reservoir operation models, this paper attempts to model the dynamic evolution of uncertainties involved in the various forecast products and explores their effect on real-time reservoir operation decisions. Through a hypothetical example of a single-objective real-time reservoir operation model, the results illustrate that forecast uncertainty exerts significant effects. Reservoir operation efficiency, as measured by a utility function, decreases as the forecast uncertainty increases but the magnitude depends on the forecast products used. In general, the utility of the reservoir operation with rPSF is nearly as high as the utility obtained with a perfect forecast. Meanwhile, the utilities of DSF and pPSF are similar to each other but not as high as rPSF. Moreover, streamflow variability and reservoir capacity can change the magnitude of the effects of forecast uncertainty, but not the relative merit of DSF, pPSF, and rPSF.  相似文献   

15.
基于河南省豫北地区跨断层形变观测资料,在排除观测时段相关干扰的基础上,选取2002—2019年观测场地周边200 km范围内中等强度地震,依据震例对应规则,使用不同类别异常提取方法进行预报方法的检验和效能评估,并通过对比分析R值检验结果,总结适用于该地区跨断层形变观测的最佳预报方法。  相似文献   

16.
On the basis that hydrological users need to know the forecast uncertainty at the time that the forecast is issued, we computed distributions of radar rainfall forecast uncertainty as a function of forecast lead time, basin size, and forecasted rainfall intensity using data from the US 3-D National Mosaic of radar data. We document how exceptional forecasts such as those of heavy rainfall are generally biased. Since forecast uncertainty is also weather dependent, we tried to find good predictors to help either reduce the forecast uncertainty or better define it. These predictors were based either on characteristics of the current precipitation field or on the performance of the nowcast in the immediate past. The value of some predictors, especially those based on the properties of large-scale rainfall patterns, was significant though modest, the predictors being generally more skillful at characterizing forecast uncertainty than at improving forecast accuracy.  相似文献   

17.
IntroductionThemodelofspatialandtemporalsynthesizedgainforastrongearthquakeoccurrenceisdevelopedasthebasisofTheDynamicSoftwareSystemforMiddle-andLong-termEarthquakeForecast.Themodelisestablishedaccordingbothtothestatisticalprincipleandtotheobservatio...  相似文献   

18.
应用灰色系统理论对1989年大同-阳高6.1级地震序列两次强余震(系指M_L≥4.7)的发震时间进行了尝试性预测,其结果与事实比较吻合,表明该方法在震后短时间内,用仅有的部分序列资料来估计其发展趋势,具有一定的实际意义。  相似文献   

19.
Forecasts of seasonal snowmelt runoff volume provide indispensable information for rational decision making by water project operators, irrigation district managers, and farmers in the western United States. Bayesian statistical models and communication frames have been researched in order to enhance the forecast information disseminated to the users, and to characterize forecast skill from the decision maker's point of view. Four products are presented: (i) a Bayesian Processor of Forecasts, which provides a statistical filter for calibrating the forecasts, and a procedure for estimating the posterior probability distribution of the seasonal runoff; (ii) the Bayesian Correlation Score, a new measure of forecast skill, which is related monotonically to theex ante economic value of forecasts for decision making; (iii) a statistical predictor of monthly cumulative runoffs within the snowmelt season, conditional on the total seasonal runoff forecast; and (iv) a framing of the forecast message that conveys the uncertainty associated with the forecast estimates to the users. All analyses are illustrated with numerical examples of forecasts for six gauging stations from the period 1971–1988.  相似文献   

20.
在统计、收集山西师范大学各类建筑物资料的基础上,对其各类建筑物进行了震害预测和经济损失估计,给出了各类建筑物在不同烈度下的破坏结果和经济损失值,为地震灾害的综合防御提供了科学依据。  相似文献   

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