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121.
Extreme learning machine for the displacement prediction of landslide under rainfall and reservoir level 总被引:3,自引:1,他引:2
Cheng Lian Zhigang Zeng Wei Yao Huiming Tang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2014,28(8):1957-1972
Landslide prediction is always the emphasis of landslide research. Using global positioning system GPS technologies to monitor the superficial displacements of landslide is a very useful and direct method in landslide evolution analysis. In this paper, an EEMD–ELM model [ensemble empirical mode decomposition (EEMD) based extreme learning machine (ELM) ensemble learning paradigm] is proposed to analysis the monitoring data for landslide displacement prediction. The rainfall data and reservoir level fluctuation data are also integrated into the study. The rainfall series, reservoir level fluctuation series and landslide accumulative displacement series are all decomposed into the residual series and a limited number of intrinsic mode functions with different frequencies from high to low using EEMD technique. A novel neural network technique, ELM, is employed to study the interactions of these sub-series at different frequency affecting landslide occurrence. Each sub-series extracted from accumulative displacement of landslide is forecasted respectively by establishing appropriate ELM model. The final prediction result is obtained by summing up the calculated predictive displacement value of each sub. The EEMD–ELM model shows the best accuracy comparing with basic artificial neural network models through forecasting the displacement of Baishuihe landslide in the Three Gorges reservoir area of China. 相似文献
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汉诺坝大麻坪低εNd中性麻粒岩包体单颗粒锆石U-Pb年代学研究 总被引:6,自引:1,他引:5
利用 LA-ICPMS对采集自汉诺坝大麻坪玄武岩中的两个 143Nd/144Nd比值最低[εNd(0)=-26.8~-29.5]的中性麻粒岩包体的单颗粒锆石 U-Pb年代学进行了研究,获得了 2 444 Ma和 2 494 Ma的上交点年龄和 88 Ma的下交点年龄,反映它们是新太古代形成的受到中生代岩浆底侵-热变质作用影响的下地壳麻粒岩.这些包体与周坝玄武岩中~1.9 Ga的长英质麻粒岩包体共同确证了华北克拉通北缘目前的下地壳中仍然残留有前寒武纪下地壳岩石.结合区域构造演化历史和 DMP-70的层状堆晶特征,推断其原岩形成于~2.5 Ga岩浆底侵事件. 相似文献
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Destructions resulted from natural hazards like earthquake, landslide, or flood in the urban roads and lifelines introduce their negative effects including the psychological damage to citizens as well as decreased urban functions that usually last for a long time. Thus, a quick and efficient recovery of infrastructures, lifelines, and service-providing facilities along with reducing reconstruction costs and time are essential. This paper proposed an approach that consists of four models for forming an algorithm in order to quantitating and integrating of the criteria that have decisive influence in the recovery of urban roadways after a natural disaster. Meanwhile, to aggregate and conclude the data that are collected by means of presented functions and formulations, we applied fuzzy VIKOR technique as a compromise ranking method. The model outputs a priority list showing the revival of which urban paths stands in higher priority for recovery operation after a natural disaster. Results show that not only the model is able to precisely quantize the selected criteria and provide an action plan for post-event recovery prioritization, but also it offers an appropriate order of transportation roads priority for recovery operations. Finally, the results from the recovery model application to a roadway system in Tehran area are provided. 相似文献
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<正>Two Mesozoic intramontane basins are developed in the Dunhuang-Yumenguan-Jiuquan area of Gansu Province,China,i.e.,the Gongpoquan Basin(E97°30′-98°10′,N41°30′-41°45′)and the Yujingzi Basin(E98°15′-99°00′,N40°15'-40°40')(Fig.1).A large number of dinosaurs and other fossils have been discovered in these two basins,which are called dinosaur'tribes'by paleontologists. 相似文献
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<正>1 Dinosaur Eggs in Yiwu City,Zhejiang Province In February 2017,dinosaur egg fossils were discovered in Chian Town part of Yiwu City,Zhejiang Province.They were confirmed by dinosaur experts from the Zhejiang Museum of Natural History to be those of Mesozoic herbivorous dinosaurs(Fig.1).Not long before,Yiwu Museum staff had discovered dinosaur eggs close by this place. 相似文献
129.
A modified Hoek-Brown failure criterion considering the damage to reservoir bank slope rocks under water saturation-dehydration circulation 总被引:1,自引:0,他引:1
After water is impounded in a reservoir, rock mass in the hydro-fluctuation belt of the reservoir bank slope is subject to water saturationdehydration circulation (WSDC). To quantify the rate of change of rock mechanical properties, samples from the Longtan dam area were measured with uniaxial compression tests after different numbers (1, 5, 10, 15, and 20) of simulated WSDC cycles. Based on the curves derived from these tests, a modified Hoek- Brown failure criterion was proposed, in which a new parameter was introduced to model the cumulative damage to rocks after WSDC. A case of an engineering application was analyzed, and the results showed that the modified Hoek-Brown failure criterion is useful. Under similar WSDC-influenced engineering and geological conditions, rock mass strength parameters required for analysis and evaluation of rock slope stability can be estimated according to this modified Hoek-Brown failure criterion. 相似文献
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《雷州歌谣话初集》系清末民初黄景星著述之研究雷州民歌的一部珍贵的历史文献,其所选雷歌数量众多,体裁各异,题材广泛,原汁原味,注重音义注解的翔实性与可靠性,编辑体例具有较强的科学性。作者对每首雷歌字词句篇的鉴赏曲尽其致,对雷歌"赋"、"比"、"兴"之叙述方式与"双关"、"顶针"、"回环"等修辞方式独抒己见,将雷歌分为"口头歌"、"班本歌"、"出榜歌"、"姑娘歌"四类,考辨出雷歌"源于清之雍康间,而盛于乾嘉,衰于咸同以后"之历史事实,值得研究雷歌的学人一读。 相似文献