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A GIS-based multi-criteria analysis model for earthquake vulnerability assessment using Choquet integral and game theory 总被引：1，自引：0，他引：1
Developing an accurate model for discharge estimation techniques of the ungauged river basin is a crucial challenge in water resource management especially in under-development regions. This article is a thorough review of the historical improvement stages of this topic to understand previous challenges that faced researchers, the shortfalls of methods and techniques, how researchers prevailed and what deficiencies still require solutions. This revision focuses on data-driven approaches and GIS-based methods that have improved the accuracy of estimation of hydrological variables, considering their advantages and disadvantages. Past studies used artificial intelligence and geo-statistical methods to forecast the runoff at ungauged river basins, and mapping the spatial distribution has been considered in this study. A recommendation for future research on the potential of a hybrid model utilizing both approaches is proposed and described. 相似文献
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Various methods are proposed to control scouring around bridge piers. In the present study application of riprap alone and combinations of riprap and collar were examined experimentally for scour control around cylindrical bridge piers. Tests were conducted with seven riprap sizes and with two different sizes of collars. Empirical equations were developed for stable riprap diameter for two cases of piers with and without collar protection. Extent of riprap layer is also presented for these two cases. The results showed that in the range of b/dR≤7.5 (where b is pier diameter and dR is riprap size) using a collar reduced the stable riprap size. It was also concluded that using collar reduced the riprap layer extension in front and sides of the pier. 相似文献
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Khodabakhshi Sureshjani Milad Amanipoor Hakimeh Battaleb-Looie Sedigheh 《Natural Resources Research》2020,29(6):3719-3741
Natural Resources Research - The physicochemical characteristics and concentrations of heavy metals from 14 groundwater and two wastewater samples were measured to evaluate the effects of various... 相似文献
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Evaluating sampling locations in river water quality monitoring networks: application of dynamic factor analysis and discrete entropy theory 总被引：1，自引：1，他引：0
In this paper, a methodology is proposed for evaluating sampling locations in an existing river water quality monitoring network. The dynamic factor analysis is utilized to extract the independent dynamic factors from time series of water quality variables. Then, the entropy theory is applied to the independent dynamic factors to construct transinformation–distance (T–D) curves. The computation time in the case of using dynamic factors is significantly less than when the raw data is used because the number of independent dynamic factors is usually much less than the number of monitored water quality variables. In this paper, it is also shown that by clustering the study area to some homogenous zones and developing T–D curves for each zone, the accuracy of the results is significantly increased. To evaluate the applicability and efficiency of the proposed methodology, it is applied to the Karoon River which is the most important river system in Iran. 相似文献
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In arid and semiarid areas, the only surface and groundwater recharge source is the runoff generated through flash floods. Lack of hydrological data in such areas makes runoff estimation extremely complicated. Flash floods are considered catastrophic phenomena posing a major hazardous threat to cities, villages, and their infrastructures. The objective of this study is to assess the flash flood hazard and runoff in Wadi Halyah and its sub-basins. Integration of morphometric parameters, geo-informatics, and hydrological models has been done to overcome the challenge of scarcity of data.Advanced Spaceborne Thermal Emission and Reflection (ASTER) data was used to prepare a digital elevation model (DEM) with 30-m resolution, and geographical information system (GIS) was used in the evaluation of network, geometry, texture, and relief features of the morphometric parameters. Thirty-eight morphometric parameters were estimated and have been linked together for producing nine effective parameters for evaluation of the flash flood hazard in the study basin.Flash flood hazard in Wadi Halyah and its sub-basins was identified and grouped into three classes depending on nine effective parameters directly influencing the flood prone areas. Calculated runoff volume of Wadi Halyah ranges from 26.7 × 106 to 111.4 × 106 m3 with an inundation area of 15 and 27 km2 at return periods of 5 and 100 years, respectively. Mathematical relationships among rainfall depth, runoff volume, infiltration losses, and rainfall excess demonstrate a strong directly proportional relationships with correlation coefficient of about 0.99. 相似文献
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Stochastic analyses of maximum daily rainfall series recorded at two stations across the Mediterranean Sea 总被引：1，自引：1，他引：0
Independence, stationarity, homogeneity, trend, and periodicity tests are applied on 48-year-long complete and 79-year-long incomplete maximum daily rainfall series recorded at Alexandria, Egypt, and on 61-year-long maximum daily rainfall series recorded at Antalya, Turkey, which are located at the southeastern and northeastern shores of the Mediterranean Sea. The results indicate no significant trend and no periodicity in mean, and both series are independent and homogeneous. Linear regression trend test applied to the 10 % highest part of the Alexandria series indicated a significant increasing trend. Next, frequency analysis is applied on each of these series by the probability distributions of Gumbel, general extreme-values, three-parameter log-normal, Pearson-3, log-Pearson-3, log-logistic, generalized Pareto, and Wakeby. The distributions, except for the generalized Pareto and Wakeby, pass the χ 2 and Kolmogorov–Smirnov goodness-of-fit tests at 90 % probability. By visual inspection of the plots of histograms together with the probability density functions, and by the results of the χ 2, Kolmogorov–Smirnov, and probability plot correlation coefficient tests, the general extreme-value distribution whose parameters are computed by the method of probability-weighted moments is deemed to be suitable for these two maximum daily rainfall series. 相似文献
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Marie Abboud-Abi Saab Jean-Claude Romano Nathaniel Bensoussan Milad Fakhri 《Comptes Rendus Geoscience》2004,336(15):1379-1390
Vertical temperature profiles were recorded from June 1999 to October 2002 (at least once a month) at two Mediterranean sites, in the eastern basin (Batroun, Lebanon; 0–100 m) and in the northwestern basin (Marseilles, France; 0–55 m). At the two sites, the thermal seasonal evolution and the thermocline time dynamics are quite identical. But in the Lebanese waters, at comparable water depths, temperatures are currently 4 to 5?°C higher than in the French waters, the thermocline is longer (more than 6 months), permanent and deeper (40–50 m) than in Marseilles (20–30 m). The latter frequently disappears in summer due to northwest winds inducing cold waters. This is principally due to differences in prevailing wind regimes at each site. Such evaluation, coupled with long-term observations of temporal evolution of coastal water at the regional level of the Mediterranean basins, will shed light on temperature regime fluctuations and their consequences in the context of global warming of the Mediterranean. To cite this article: M. Abboud-Abi Saab et al., C. R. Geoscience 336 (2004). 相似文献
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The problem of the through-soil coupling of structures has puzzled the researchers in the field for a long while, especially regarding the varied performance of identical, adjacent buildings in earthquakes. The phenomenon of structure-soil-structure interaction (SSSI) that has often been overlooked is recently being recognized: The possible effects in urban regions are yet to be thoroughly quantified. In this respect, the goal of this work was to rigorously investigate the interacting effects of adjacent buildings in a two-dimensional setting. Detailed finite element models of 5-, 15-, and 30-story structures, realistically designed, were used in forming building clusters on the viscoelastic half-space. Perfectly matched layers were used to properly define the half-space boundaries. The interaction of the structure and the soil medium because of the presence of spatially varying ground motion on the boundary of excavated region was considered. The effects of the foundation material and the distance between adjacent buildings on the structural behavior of the neighboring buildings were investigated using drift ratios and base shear quantities as the engineering demand parameters of interest. The effects of SSSI, first investigated in the frequency domain, was then quantified in the time domain using suites of appropriate ground motions in accordance with the soil conditions, and the results were compared with the counterpart SSI solution of a single building. The results showed that, for identical low-rise structures, the effects of SSSI were negligible. Yet, neglecting SSSI for neighboring closely spaced high-rise structures or building clusters with a large stiffness contrast was shown to lead to a considerable underestimation of the true seismic demands even compared with solutions obtained using the rigid base assumption. 相似文献