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1.
Contingency plans for hazards are based on scenarios at different scales. The most extreme scenarios reflect the idea of ‘think the unthinkable’. For large‐scale floods in the Netherlands, this idea has been given an upper limit called ‘worst credible floods’: an upper limit for floods that are still considered realistic or credible by experts. Considering the enormous impact of a worst credible flood in the Netherlands and the uncertainty of how a disaster might unfold, a realistic preparation for flood disasters should leave room for improvisation and should be based on relatively simple plans, and on public awareness. The huge consequences of worst credible floods show that the country's safety will continue to depend on pro‐active and preventive measures. 相似文献
2.
Vahid Nourani Mohammad T. Alami Mohammad H. Aminfar 《Engineering Applications of Artificial Intelligence》2009,22(3):466-472
Doubtlessly the first step in a river management is the precipitation modeling over the related watershed. However, considering high-stochastic property of the process, many models are being still developed in order to define such a complex phenomenon in the field of hydrologic engineering. Recently artificial neural network (ANN) as a non-linear inter-extrapolator is extensively used by hydrologists for rainfall modeling as well as other fields of hydrology.In the current research, the wavelet analysis was linked to the ANN concept for prediction of Ligvanchai watershed precipitation at Tabriz, Iran. For this purpose, the main time series was decomposed to some multi-frequently time series by wavelet theory, then these time series were imposed as input data to the ANN to predict the precipitation 1 month ahead. The obtained results show the proposed model can predict both short- and long-term precipitation events because of using multi-scale time series as the ANN input layer. 相似文献
3.
Yiming Wei Weixuan Xu Ying Fan Hsien-Tang Tasi 《Computers & Industrial Engineering》2002,42(2-4):383-390
Most of flood disaster predictions belong to ill-structured problems, while artificial neural network (ANN) has several characteristics that are suitable for solving them. In this paper, a neural network based predictive method for flood disaster problem is proposed in which the neural network model and its basic designing principles are described, and an example of flood disaster area in China from 1949 to 1994 is used for demonstration. 相似文献
4.
The analysis of the spatial extent and temporal pattern of flood inundation from remotely sensed imagery is of critical importance to flood mitigation. With a high frequency of global coverage, NOAA/AVHRR has the advantage of detecting flood dynamics during devastating floods. In this paper, we describe a systematic approach to flood monitoring using AVHRR data. Four critical issues for successful flood monitoring with AVHRR were identified: correct identification of water bodies, effective reduction of cloud contamination, accurate area estimation of flood extent, and dynamic monitoring of flood processes. In accordance with the spectral characteristics of water and land in AVHRR channels, a simple but effective water identification method was developed with the ability to reduce cloud influences. The area of flooded regions was calculated with the consideration of areal distortion due to map projection, and mixed pixels at water/land boundaries. Flood dynamics were analysed from flood distributions in both space and time. The maximum spatial extent of floods, generated by compiling the time series of flood maps, was informative about flood damages. We report a successful use of this approach to monitor the Huaihe river flood, a centennial devastating disaster occurred in the Huaihe river basin of China in the summer of 1991. 相似文献
5.
Snehashish Chakraverty Pallavi Gupta Sunita Sharma 《Neural computing & applications》2010,19(3):367-375
This article uses powerful technique of artificial neural network (ANN) models to simulate and estimate structural response
of two-storey shear building by training the model for a particular earthquake. The neural network is first trained for a
real earthquake data and the numerically generated responses of different floors of two-storey buildings as the training patterns.
Trained ANN architecture is then used to simulate and test the structural response of different floors for various intensity
earthquake data and it is found that the predicted responses given by ANN model are good for practical purposes. It is worth
mentioning that although the simulation is done with numerically generated response data for particular earthquake, the idea
may also be used for actual experimental (response) data. 相似文献
6.
Li‐Hua Feng 《Expert Systems》2013,30(5):398-402
Mappings of the stimuli effects and the input and output estimates of artificial neural networks (ANN) are obtained via combinations of nonlinear functions. This approach offers the advantages of self‐learning, self‐organization, self‐adaptation, and fault tolerance as well as the potential for use in flood forecasting applications. Furthermore, the ANN technology allows the use of multiple variables in both the input and output layers. This capability is very important for flood calculation because the stage, discharge, and other hydrological variables often are functions of many influential variables. Herein, we propose a flood forecasting system with related application, based on ANN. This method offers better performance and efficiency. 相似文献
7.
利用研究区获得的水文观测资料,采用模块开发和系统集成方式,研制了研究区流域降水预报系统。介绍了系统的体系结构、主要功能、运行情况及开发的关键技术。叙述了流域降水预报的各种预报方法,并建立了基于遗传算法的降水预报神经网络模型(GA-BP网络模型)。结果表明,GA-BP网络是一种精度较高的降水预报模型,提高预测精度,增长有效预见期。该系统能根据流域观测数据、高空数据、卫星云图、数值产品等数据,实现不同数据源的信息处理和不同时效的降水预报制作,为洪水预警预报和防洪决策服务。 相似文献
8.
《Engineering Applications of Artificial Intelligence》2006,19(6):681-691
An artificial neural network (ANN) model for predicting the failure rate of De Havilland Dash-8 airplane tires utilizing the two-layered feed-forward back-propagation algorithm as a learning rule is developed. The inputs to the neural network are independent variables and the output is the failure rate of the tires. Six years of data are used for model building and validation. Model validation, which reflects the suitability of the model for future prediction is performed by comparing the predictions of the model with that of Weibull regression model. The results show that the failure rate predicted by the ANN is closer in agreement with the actual data than the failure rate predicted by the Weibull model. 相似文献
9.
Raja Chakraborty Paolo Ferrazzoli Rachid Rahmoune 《International journal of remote sensing》2013,34(16):6310-6328
In this article, passive microwave observations in synergy with optical data are exploited to monitor floods and estimate vegetation submerging. The selected site is Sundarban Delta, at the borders between India and Bangladesh. The area is subject to severe monsoon in summer, producing heavy floods and vegetation submerging. Because of their high spatial resolution, Moderate Resolution Imaging Spectroradiometer (MODIS) signatures are used to evaluate the coverage fractions of bare soil, vegetated fields, and permanent water. Multifrequency Advanced Microwave Scanning Radiometer Earth Observing System (AMSR-E) signatures are used to monitor vegetation submerging during monsoon. Results are compared with ground measurements of water level and plant biomass in both agriculture areas and wetlands. Previous studies indicated that, during monsoon, there is a clear effect of brightness temperature decrease and polarization index increase in the C, X and Ka bands over the areas affected by floods. X band data prove to be particularly useful since the sensitivity to flood effects is appreciable and the spatial resolution is better than at C band. In this article, the vegetation submerging effect is estimated with the aid of a radiative transfer model. In the pre-monsoon season, the retrieved value of emerged biomass is close to that of the measured total biomass. During monsoon, it is estimated that up to 3 kg m?2 of vegetation biomass is submerged by flood. For both agricultural fields and wetlands, obtained results are consistent with ground measurements of water level. 相似文献
10.
As churn management is a major task for companies to retain valuable customers, the ability to predict customer churn is necessary. In literature, neural networks have shown their applicability to churn prediction. On the other hand, hybrid data mining techniques by combining two or more techniques have been proved to provide better performances than many single techniques over a number of different domain problems. This paper considers two hybrid models by combining two different neural network techniques for churn prediction, which are back-propagation artificial neural networks (ANN) and self-organizing maps (SOM). The hybrid models are ANN combined with ANN (ANN + ANN) and SOM combined with ANN (SOM + ANN). In particular, the first technique of the two hybrid models performs the data reduction task by filtering out unrepresentative training data. Then, the outputs as representative data are used to create the prediction model based on the second technique. To evaluate the performance of these models, three different kinds of testing sets are considered. They are the general testing set and two fuzzy testing sets based on the filtered out data by the first technique of the two hybrid models, i.e. ANN and SOM, respectively. The experimental results show that the two hybrid models outperform the single neural network baseline model in terms of prediction accuracy and Types I and II errors over the three kinds of testing sets. In addition, the ANN + ANN hybrid model significantly performs better than the SOM + ANN hybrid model and the ANN baseline model. 相似文献
11.
《Environmental Modelling & Software》2007,22(10):1409-1416
Rome's monumental centre has often been inundated by Tiber River. In the last decades of the 19th century, river walls were erected to protect Rome from floods so that the last significant flood, which occurred in 1937, caused only marginal damages. Although the probability of inundation of the city seems to be now substantially reduced, the evaluation of the residual risk is still worthwhile. With this aim, rainfall, rainfall–runoff, river flood propagation and street flooding processes are simulated in detail to produce the inundation scenarios analysed by the Monte Carlo method. The study shows that severe floods, having a return period greater than 180 years, overtop both the left and right river banks and inundate the northern outskirts of Rome, while extreme events, with 1000 years return period, submerge large parts of the monumental centre of Rome. 相似文献
12.
基于COSMOGSkyMed和SPOTG5的城镇洪水淹没信息快速提取研究 总被引:1,自引:0,他引:1
洪水是我国最为频繁的自然灾害之一,如何快速准确地获取洪水淹没范围在救灾减灾工作中具有重要意义.目前,卫星遥感技术已广泛应用于洪水信息提取的研究中.不同的遥感数据源在洪水信息提取中各有利弊,综合研究雷达影像和可见光影像的优缺点,建立了基于多源遥感数据的洪水淹没信息快速提取模型.首先,利用灾中第一时间获取的COSMOGSkyMed雷达影像,采用面向对象的方法提取出洪灾发生时的水域空间信息;其次,利用灾前SPOTG5高分辨率光学影像,采用多光谱影像波段运算和决策树分类的思想提取出常态下的水域空间信息;最后,对灾中雷达影像COSMOGSkyMed提取的水体和灾前光学影像SPOTG5提取的水体进行空间差值运算,得到洪水淹没范围信息,并利用洪水当天拍摄的无人机遥感影像对结果进行精度评价.将该模型应用于2013年浙江余姚水灾,监测结果表明:在洪水发生后,能够快速获取淹没范围空间信息,并且提取精度达到93.7%,为洪灾的防治以及抗洪抢险救灾工作提供强有力的技术支撑和基础数据信息. 相似文献
13.
Algal blooms are one of the most prevalent global problems. Studying the Chlorophyll-a (Chl-a) predicting model helps to control algal blooms. Predicting the behavior of algae is difficult because of the complex physical, chemical, and biological processes involved. Artificial neural network (ANN) models have been determined to be useful and efficient, especially for such problems for which the characteristics of the processes are difficult to describe using numerical models. An indoor simulated environment is designed for algal cultivation to analyze the temporal change in the algae biomass of Taihu Lake during summer. A Chl-a prediction model based on a nonlinear autoregressive neural network with exogenous inputs (NARX) that can detect and consider within the time dependency is proposed. The NARX model is compared to a static neural network and a dynamic neural network: feedforward neural network (FNN) and Elman recurrent neural network (ERNN). The performance of the proposed NARX model was examined with experimental data collected over 3 months in 2010. The results showed that the NARX model outperformed the other ANN models and significantly enhance the accuracy of Chl-a prediction. 相似文献
14.
E. W. M. Lee I. W. H. Fung V. W. Y. Tam M. Arashpour 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2014,18(10):1999-2014
Building cooling load prediction is critical to the success of energy-saving measures. While many of the computational models currently available in the industry have been developed for this purpose, most require extensive computer resources and involve lengthy computational processes. Artificial neural networks (ANNs) have recently been adopted for prediction, and pioneering works have confirmed the feasibility of this approach. However, users are required to predetermine an ANN model’s parameters. This hinders the applicability of the ANN approach in actual engineering problems, as most engineers may be unfamiliar with soft computing. This paper proposes a fully autonomous kernel-based neural network (AKNN) model for noisy data regression prediction. No part of the model’s mechanism requires human intervention; rather, it self-organises its structure according to the training samples presented. Unlike the other existing autonomous models, the AKNN model is an online learning model. It is particularly suitable for online steps-ahead prediction. In this paper, we benchmark the AKNN model’s performance according to other ANN models. It is also successfully applied to predicting the cooling load of a commercial building in Hong Kong. The occupancy areas and concentration of carbon dioxide inside the building are successfully adopted to mimic the building’s internal cooling load. Training data was adopted from actual measurements taken inside the building. Its results show reasonable agreement with actual cooling loads. 相似文献
15.
Mehmet Şahin 《International journal of remote sensing》2013,34(21):7508-7533
In this study, solar radiation (SR) is estimated at 61 locations with varying climatic conditions using the artificial neural network (ANN) and extreme learning machine (ELM). While the ANN and ELM methods are trained with data for the years 2002 and 2003, the accuracy of these methods was tested with data for 2004. The values for month, altitude, latitude, longitude, and land-surface temperature (LST) obtained from the data of the National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer (NOAA-AVHRR) satellite are chosen as input in developing the ANN and ELM models. SR is found to be the output in modelling of the methods. Results are then compared with meteorological values by statistical methods. Using ANN, the determination coefficient (R2), mean bias error (MBE), root mean square error (RMSE), and Willmott’s index (WI) values were calculated as 0.943, ?0.148 MJ m?2, 1.604 MJ m?2, and 0.996, respectively. While R2 was 0.961, MBE, RMSE, and WI were found to be in the order 0.045 MJ m?2, 0.672 MJ m?2, and 0.997 by ELM. As can be understood from the statistics, ELM is clearly more successful than ANN in SR estimation. 相似文献
16.
Timothy J. Haney 《突发事故与危机管理杂志》2019,27(3):224-236
Post‐disaster migration patterns have been thoroughly studied from a demographic standpoint, but affected community residents’ perceptions of ongoing risks and their willingness to remain in an affected community remain under‐researched. Using data generated by 407 surveys and 40 interviews with residents impacted by the 2013 Calgary flood, this study analyses the effects of flood experience on residents’ worry about future floods and their ensuing short‐term and medium‐term mobility plans. The results indicate that home flooding and evacuation orders are both predictive of worry about future floods. In turn, worry about future floods as well as age, homeownership, and place attachment are all predictive of post‐disaster mobility plans. Residents discuss how the flood either strengthened or weakened their place attachment. The paper concludes by discussing the implications for social science research and for public policy that aims to mitigate disaster risk. 相似文献
17.
《International journal of remote sensing》2012,33(8):3221-3242
ABSTRACTSea Surface Salinity (SSS) is a pre-eminent parameter in oceanology causing extreme climate and weather events such as floods and droughts. Therefore, knowledge discovery of SSS is increasingly becoming a fundamental problem in recent years. However, not only the inadequacy of in-situ SSS data in large ocean basins are hampering conduction of detailed analyses of patterning SSS variations but also conventional data-gathering techniques for SSS estimation are often too expensive and time-consuming to meet the amount of data required in SSS estimation studies. Conversely, the brand-new Soil Moisture Active-Passive (SMAP) mission could provide validated SSS data along with its main objective soil moisture retrieval. As a result, collecting a candidate data set of surface’s parameters as inputs to SSS with the aid of Pearson correlation and Boruta feature selection techniques, this paper aims to study the predictive skills of machine learning approaches to estimate SMAP radiometer SSS in the Persian Gulf region from April 2015 to April 2017. Thus, four machine learning methods including Support Vector Regression (SVR), artificial neural network (ANN), random forest (RF) and gradient boosting machine (GBM) were adopted to model the SSS. Two approaches of GBM and RF provided scarcely equivalent predictions for both the calibration and validation data sets that were distinguishably substantiated by experimental results and simulations, nonetheless, slightly superior results were attained with the GBM model by correlation coefficient (r) = 0.734, root mean squared error (RMSE) = 0.906 and mean absolute error (MAE) = 0.627. The findings demonstrate promising SSS estimation from SMAP, which could provide a baseline to perceive the large-scale changes in SSS. 相似文献
18.
Flooding causes more financial and physical destruction in the United States than any other natural hazard. To stem flood losses, local floodplain managers make decisions on how best to mitigate, prepare, and respond to flood hazards. Using quantitative and qualitative data gathered from interviews with 200 floodplain managers in the United States, this study explores the extent to which local communities are concerned about floods, perceptions of communities' ability to mitigate, prepare, and respond to floods, as well as the factors contributing to communities' perceptions of their ability to mitigate, prepare, and respond to floods. Findings indicate that floodplain managers generally perceived their communities to be very or somewhat concerned and prepared for floods. Floodplain managers also perceived their communities' ability to mitigate and respond to floods as being good. Lastly, the findings show that participation in the Federal Emergency Management Agency's Community Rating System was positively associated with floodplain managers' perceptions of their community's ability to mitigate, prepare, and respond to floods. 相似文献
19.
Forecasting of Software Reliability Using Neighborhood Fuzzy Particle Swarm Optimization Based Novel Neural Network
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Pratik Roy Ghanshaym Singha Mahapatra Kashi Nath Dey 《IEEE/CAA Journal of Automatica Sinica》2019,6(6):1365-1383
This paper proposes an artificial neural network (ANN) based software reliability model trained by novel particle swarm optimization (PSO) algorithm for enhanced forecasting of the reliability of software. The proposed ANN is developed considering the fault generation phenomenon during software testing with the fault complexity of different levels. We demonstrate the proposed model considering three types of faults residing in the software. We propose a neighborhood based fuzzy PSO algorithm for competent learning of the proposed ANN using software failure data. Fitting and prediction performances of the neighborhood fuzzy PSO based proposed neural network model are compared with the standard PSO based proposed neural network model and existing ANN based software reliability models in the literature through three real software failure data sets. We also compare the performance of the proposed PSO algorithm with the standard PSO algorithm through learning of the proposed ANN. Statistical analysis shows that the neighborhood fuzzy PSO based proposed neural network model has comparatively better fitting and predictive ability than the standard PSO based proposed neural network model and other ANN based software reliability models. Faster release of software is achievable by applying the proposed PSO based neural network model during the testing period. 相似文献
20.
《Computers & Structures》2006,84(26-27):1709-1718
An artificial neural network (ANN) based approach is presented for the assessment of damage in prestressed concrete beams from natural frequency measurements. The details of an experimental programme suitably designed and carried out to induce the desired extents of damages in the prestressed concrete beams and generate the training and test data for the ANN are presented. The analysis of the static and dynamic behavior of perfect and damaged prestressed concrete beams reveal that there exists a close relationship among the natural frequency, deflection, crack width, first crack load, ultimate load and degree of damage. Therefore, these parameters were mainly used as input data for training and testing the ANN. A feed forward ANN learning by back propagation algorithm implemented using MATLAB has been employed in this study. The main focus of this work has been to study the feasibility of using an ANN trained with only natural frequency data to assess the damage in prestressed concrete beams. This is explored by comparing the performance of an ANN trained only with natural frequency data with other ANNs trained with a mix of static and dynamic data. It has been demonstrated that an ANN trained only with dynamic data can assess the damage with less than 10% error, when the error is the difference between the actual damage in percent and predicted damage in percent. The shortcomings of this study have also been presented. 相似文献