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1.
Urban stormwater thermal gene expression models for protection of sensitive receiving streams 下载免费PDF全文
Thermal impact of typical high‐density residential, industrial, and commercial land uses is a major concern for the health of aquatic life in urban watersheds, especially in smaller, cold, and cool‐water streams. This is the first study of its kind that provides simple easy‐to‐use equations, developed using gene expression programming (GEP) that can guide the assessment and the design of urban stormwater management systems to protect thermally sensitive receiving streams. We developed 3 GEP models using data collected during 3 years (2009–2011) from 4 urban catchments; the first GEP model predicts event mean temperature at the inlet of the pond; the second model predicts the stormwater temperature at the outlet of the pond; and the third model predicts the temperature of the stormwater after flowing through a cooling trench and before discharging to the receiving stream. The new models have high correlation coefficients of 0.90–0.94 and low prediction uncertainty of less than 4% of the median value of the predicted runoff temperatures. Sensitivity analysis shows that climatic factors have the highest influence on the thermal enrichment followed by the catchment characteristics and the key design variables of the stormwater pond and the cooling trench. The general method presented here is easily transferable to other regions of the world (but not necessarily the exact equations developed here); also through sensitivity and parametric analysis, we gained insight on the key factors and their relative importance in modelling thermal enrichment of urban stromwater runoff. 相似文献
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M. A. F. M. Rashidul Hasan M. M. Keramat S. Shahid R. Yasmin M. Mohsenipour Golam Shabbir Sattar 《Geotechnical and Geological Engineering》2016,34(5):1395-1411
Barind Tract, located north western part of Bangladesh, is one of the most diversified physiographic units of the country. The surface water supply in this part is particularly limited, so the irrigation is almost entirely depends on groundwater. However, over exploitation indicates falling groundwater heads in this area. The objective of present study is to examine the nature of the aquifer system Barind Tract of Bangladesh in order to assess the sustainability of groundwater yield. Borehole lithology data were collected, processed and analyzed for this purpose. Representative panel diagram, 3-D stratigraphic and cross-sectional views were also prepared for necessary assessment of the variation of individual subsurface stratum in different locations. The study identified three subsurface geologic formations namely, a top clay layer, sand layer of different grain size and at the bottom an impermeable clay zone. Maps of formation thickness and index revealed that aquifer thickness is low in the north-western corner and in some places of middle of south-western corner. The thickness of sand formation in other places is recorded above 20 m. It is expect that the finding of the study will help groundwater resources development, planning and management in the area. 相似文献
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Nagpal Anushree Hassan Mohammad Siddiqui Masood Ahsan Tajdar Atiqua Hashim Mohammad Singh Abhra Gaur Suman 《GeoJournal》2021,86(2):649-661
GeoJournal - Sanitation is a multidimensional concept alluding primarily to provision of services for safe disposal of human excreta, provision of clean potable water as well as maintenance of... 相似文献
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Natural Hazards - The article was published with the citation “Worni et al. (2012)”. The author group of the article would like readers to know that this information should instead... 相似文献
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Jewgenij Torizin Michael Fuchs Adnan Alam Awan Ijaz Ahmad Sardar Saeed Akhtar Simon Sadiq Asif Razzak Daniel Weggenmann Faseeh Fawad Nimra Khalid Faisan Sabir Ahsan Jamal Khan 《Natural Hazards》2017,87(2):757-771
This paper presents laboratory experiments and numerical simulations of effects of submerged obstacles on tsunami-like solitary wave and its run-up. This study was carried out for the breaking and non-breaking solitary waves on 1:19.85 uniform slope which contains a submerged obstacle. New laboratory experiments are performed to describe the mitigation of tsunami amplitude and run-up under the effect of submerged obstacles. We are based on experimental results obtained to validate the numerical model. The numerical modeling using COULWAVE aims essentially to show the effect of the obstacle on the shape of solitary wave and the limit of this effect. Using a multiple nonlinear regression, we have determined a model to estimate height of run-up according to the amplitude of the wave and the obstacle peak depth. 相似文献
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The 8th October 2005 Kashmir Earthquake of magnitude 7.6 triggered a huge landslide 3.5 km upstream of Hattian Bala town in
the state of Azad Jammu Kashmir of Pakistan. The debris mass blocked two tributaries of the Karli branch of the Jhelum River
and was breached on 9th February 2010. This debris dam provided us with a rare opportunity to keep careful and continuous
eyes on its post-earthquake behavior especially as it was a serious threat to people living along the lower reaches of both
the Karli and Jhelum Rivers. This paper describes post-formation behaviors of the debris mass, breaching-inflicted changes
of not only the debris mass but also both upstream and downstream reaches based upon laser-scanned images of landforms and
Differential Global Positioning System survey results. 相似文献
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A transversely isotropic material in the sense of Green is considered. Using a series of potential functions proposed in [Eskandari-Ghadi M. A complete solution of the wave equations for transversely isotropic media. J Elasticity 2005; 81:1–19], the solutions of the transient wave equations within a half-space under surface load are obtained in the Laplace–Hankel domain for axisymmetric problems. The solutions are investigated in detail in the special case of a surface point force pulse varying with time as Heaviside function. Using Cagniard–De Hoop method, the inverse Laplace transform and inverse Hankel transform of the solutions are then obtained in the form of integrals with finite limits. For validity of the analytical results, the final formulations for surface waves are degenerated for an isotropic material and compared with the existing formulation obtained by Pekeris [The seismic surface pulse. Proc Natl Acad Sci USA 1955;41:469–80], to show that they are exactly the same. The numerical evaluations of the integrals for some transversely isotropic materials as well as an isotropic one are obtained. The present approach is then numerically verified by comparing a particular case of displacements for the surface of an isotropic half-space subjected to a point load of Heaviside function with the solutions obtained by Pekeris [The seismic surface pulse. Proc Natl Acad Sci USA 1955;41:469–80]. In addition, the wave equations for the mentioned medium are obtained on the vertical line directly under the applied surface load. The final formulations are degenerated for an isotropic material and compared with the existing formulation given in Graff [Wave motion in elastic solids. New York: Dover Publications Inc; 1975 [New Ed edition, November 1991]], to show that they are also exactly the same. Then equations are presented in graphical forms using an appropriate numerical evaluation. 相似文献
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Pamela L. Nagler Armando Barreto-Muñoz Sattar Chavoshi Borujeni Christopher J. Jarchow Martha M. Gómez-Sapiens Hamideh Nouri Stefanie M. Herrmann Kamel Didan 《水文研究》2020,34(25):4851-4883
Hydrological and bioclimatic processes that lead to drought may stress plants and wildlife, restructure plant community type and architecture, increase monotypic stands and bare soils, facilitate the invasion of non-native plant species and accelerate soil erosion. Our study focuses on the impact of a paucity of Colorado River surface flows from the United States (U.S.) to Mexico. We measured change in riparian plant greenness and water use over the past two decades using remotely sensed measurements of vegetation index (VI), evapotranspiration (ET) and a new annualized phenology assessment metric (PAM) for ET. We measure these long-term (2000–2019) metrics and their short-term (2014–2019) response to an environmental pulse flow in 2014, as prescribed under Minute 319 of the 1944 Water Treaty between the two nations. In subsequent years, small-directed flows were provided to restoration areas under Minute 323. We use 250 m MODIS and 30 m Landsat imagery to evaluate three vegetation indices (NDVI, EVI, EVI2). We select EVI2 to parameterize an optical-based ET algorithm and test the relationship between ET from Landsat and MODIS by regression approaches. Our analyses show significant decreases in VIs and ET for both the 20-year and post-pulse 5-year periods. Over the last 20 years, EVI Landsat declined 34% (30% by EVIMODIS) and ETLandsat-EVI declined 38% (27% by ETMODIS-EVI), overall ca. 1.61 mm/day or 476 mm/year drop in ET; using PAM ETLandsat-EVI the drop was from 1130 to 654 mm/year. Over the 5 years since the 2014 pulse flow, EVILandsat declined 20% (13% by EVIMODIS) and ETLandsat-EVI declined 23% (4% by ETMODIS-EVI) with a 0.77 mm/day or a 209 mm/year 5-year drop in ET; using PAM ETLandsat-EVI the drop was from 863 to 654 mm/year. Data and change maps show the pulse flow contributed enough water to slow the rate of loss, but only for the very short-term (1–2 years). These findings are critically important as they suggest further deterioration of biodiversity, wildlife habitat and key ecosystem services due to anthropogenic diversions of water in the U.S. and Mexico and from land clearing, fires and plant-related drought which affect hydrological processes. 相似文献
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The effect of Hall currents and collision with neutrals on the instability of a horizontal layer of a self-gravitating partially-ionized plasma of varying density have been studied. It is assumed that the plasma is permeated by a variable horizontal magnetic field stratified vertically. A variational principle is shown to characterize the problem. By making use of the existence of the variational principle, proper solutions have been obtained for a semi-infinite plasma in which density has a one-dimensional (exponential) vertical stratification. The dispersion relation has been derived and solved numerically. It is found that the collisions with neutrals have a stabilizing influence while Hall currents have a destabilizing influence. 相似文献