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Flash flood simulations for an Egyptian city - mitigation measures and impact of infiltration
Within this work, the impact of mitigation measures and infiltration on flash floods is investigated by using a 2D robust shallow water model including infiltration with the Green-Ampt model. The results show the combined effects of infiltration and mitigation measures as well as the effectiveness of bypass channels in addition to retention basins. Retention basins at appropriate locations could reduce the maximum water depth at critical locations by 23%, while the additional implementation of drainage channels lead to a reduction of 75%, considering also infiltration lead to a further reduction of 97%. If infiltration was considered without mitigation measures, the peak water depth was reduced by 67%. For an exceptional extreme event the measures lead to a reduction of 73% at some locations, while at other locations the overflow from retention basins due to overstraining generated even higher inundations with an increase of 58%
Additional Notes on Delphacidae, Tettigometridae and Cixidae [Auchenorrhyncha (Insecta: Hemiptera)] Fauna in East and Southeast Anatolia Region of Turkey
This study was carried out to contribute the Delphacidae, Tettigometridae and Cixiidae (Hemiptera) fauna in the East and Southeast Anatolia Region of Turkey. Specimens were collected from different locations of the study area, in 2007, 2008, 2014 and 2015, and prepared according to standard methods. 7 species belonging to 6 genera from 3 families were determined: Hyalesthes obsoletus, Pentastiridius leporinus, Laodelphax striatellus, Sogatella vibix, Toya propinqua, Tettigometra atra and Tettigometra macrocephala. Number of examined specimens, host plants and distribution of species in Turkey have been given. In these species; P. leporinus, L. striatellus T. atra, T. macrocephala were new records in these regions
Wave propagation speeds and source term influences in single and integral porosity shallow water equations
In urban flood modeling, so-called porosity shallow water equations (PSWEs), which conceptually account for unresolved structures, e.g., buildings, are a promising approach to addressing high CPU times associated with state-of-the-art explicit numerical methods. The PSWE can be formulated with a single porosity term, referred to as the single porosity shallow water model (SP model), which accounts for both the reduced storage in the cell and the reduced conveyance, or with two porosity terms: one accounting for the reduced storage in the cell and another accounting for the reduced conveyance. The latter form is referred to as an integral or anisotropic porosity shallow water model (AP model). The aim of this study was to analyze the differences in wave propagation speeds of the SP model and the AP model and the implications of numerical model results. First, augmented Roe-type solutions were used to assess the influence of the source terms appearing in both models. It is shown that different source terms have different influences on the stability of the models. Second, four computational test cases were presented and the numerical models were compared. It is observed in the eigenvalue-based analysis as well as in the computational test cases that the models converge if the conveyance porosity in the AP model is close to the storage porosity. If the porosity values differ significantly, the AP model yields different wave propagation speeds and numerical fluxes from those of the BP model. In this study, the ratio between the conveyance and storage porosities was determined to be the most significant parameter
Comparison of depth-averaged concentration and bed load flux sediment transport models of dam-break flow
This paper presents numerical simulations of dam-break flow over a movable bed. Two different mathematical models were compared: a fully coupled formulation of shallow water equations with erosion and deposition terms (a depth-averaged concentration flux model), and shallow water equations with a fully coupled Exner equation (a bed load flux model). Both models were discretized using the cell-centered finite volume method, and a second-order Godunov-type scheme was used to solve the equations. The numerical flux was calculated using a Harten, Lax, and van Leer approximate Riemann solver with the contact wave restored (HLLC). A novel slope source term treatment that considers the density change was introduced to the depth-averaged concentration flux model to obtain higher-order accuracy. A source term that accounts for the sediment flux was added to the bed load flux model to reflect the influence of sediment movement on the momentum of the water. In a one-dimensional test case, a sensitivity study on different model parameters was carried out. For the depth-averaged concentration flux model, Manning's coefficient and sediment porosity values showed an almost linear relationship with the bottom change, and for the bed load flux model, the sediment porosity was identified as the most sensitive parameter. The capabilities and limitations of both model concepts are demonstrated in a benchmark experimental test case dealing with dam-break flow over variable bed topography
The triticeous cartilage — redefining of morphology, prevalence and function
Background: Triticeous cartilage is a small cartilaginous component of the laryngeal skeleton. This cartilage, located in posterior end of the thyrohyoid ligament, presents in different shapes. Radiological studies indicate clinical and anatomical importance of the triticeous cartilage but these studies have limited information due to inadequate inspection method. Computed tomographic angiography is able to evaluate the triticeous cartilage with using three-dimensional images in more detail. The aim of this study is to describe prevalence and morphological properties of the triticeous cartilage.
Materials and methods: We examined computed tomographic angiography images of 746 patients (368 women, 378 men) retrospectively. Shapes, calcification degrees, volumes, lengths and wideness of the triticeous cartilage were evaluated by OsiriX-Lite software.
Results: According to our results, triticeous cartilage presents common in the examined population (68.1%). The prevalence of the triticeous cartilage was higher in men than in women. We also found that the degree of calcification was not related with age and gender.
Conclusions: Clinical importance of the triticeous cartilage is that it could be misdiagnosed with atherosclerosis in common carotid artery because the triticeous cartilage is located almost at same level as the bifurcation of the common carotid artery. Therefore, clinicians should be aware about the triticeous cartilage
Urban flood modeling using shallow water equations with depth-dependent anisotropic porosity
The shallow water model with anisotropic porosity conceptually takes into account the unresolved subgrid-scale features, e.g. microtopography or buildings. This enables computationally efficient simulations that can be run on coarser grids, whereas reasonable accuracy is maintained via the introduction of porosity. This article presents a novel numerical model for the depth-averaged equations with anisotropic porosity. The porosity is calculated using the probability mass function of the subgrid-scale features in each cell and updated in each time step. The model is tested in a one-dimensional theoretical benchmark before being evaluated against measurements and high-resolution predictions in three case studies: a dam-break over a triangular bottom sill, a dam-break through an idealized city and a rainfall-runoff event in an idealized urban catchment. The physical processes could be approximated relatively well with the anisotropic porosity shallow water model. The computational resolution influences the porosities calculated at the cell edges and therefore has a large influence on the quality of the solution. The computational time decreased significantly, on average three orders of magnitude, in comparison to the classical high-resolution shallow water model simulation.Chinese Scholarship Counci
Shallow water simulation of overland flows in idealised catchments
This paper investigates the relationship between the rainfall and runoff in idealised catchments, either with or without obstacle arrays, using an extensively-validated fullydynamic shallow water model. This two-dimensional hydrodynamic model allows a direct transformation of the spatially distributed rainfall into the flow hydrograph at the catchment outlet. The model was first verified by reproducing the analytical and experimental results in both one-dimensional and two-dimensional situations. Then, dimensional analyses were exploited in deriving the dimensionless S-curve, which is able to generically depict the relationship between the rainfall and runoff. For a frictionless plane catchment, with or without an obstacle array, the dimensionless Scurve seems to be insensitive to the rainfall intensity, catchment area and slope, especially in the early steep-rising section of the curve. Finally, the model was used to study the hydrological response of an idealised catchment covered with buildings, which were represented as an obstacle array. The influences of the building array size and layout on the catchment response were presented in terms of the dimensionless time at which the catchment outflow reaches 50% of the equilibrium value.Dr. Liang and Prof. Hinkelmann thank the Alexander von Humboldt Foundation for providing the opportunity for their collaboration. Dr. Liang thanks the financial support by the Royal Academy of Engineering (NRCP/1415/97 and ISS1516\8\34). Prof. Xiao and Dr. Chen thank the financial support by the National Natural Science Foundation of China (51450110079) and Chinese Academy of Engineering (2015-ZD-07-04-01).This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s12665-015-4744-
SERGHEI (SERGHEI-SWE) v1.0: a performance-portable high-performance parallel-computing shallow-water solver for hydrology and environmental hydraulics
The Simulation EnviRonment for Geomorphology, Hydrodynamics, and Ecohydrology in Integrated form (SERGHEI) is a multi-dimensional, multi-domain, and multi-physics model framework for environmental and landscape simulation, designed with an outlook towards Earth system modelling. At the core of SERGHEI's innovation is its performance-portable high-performance parallel-computing (HPC) implementation, built from scratch on the Kokkos portability layer, allowing SERGHEI to be deployed, in a performance-portable fashion, in graphics processing unit (GPU)-based heterogeneous systems. In this work, we explore combinations of MPI and Kokkos using OpenMP and CUDA backends. In this contribution, we introduce the SERGHEI model framework and present with detail its first operational module for solving shallow-water equations (SERGHEI-SWE) and its HPC implementation. This module is designed to be applicable to hydrological and environmental problems including flooding and runoff generation, with an outlook towards Earth system modelling. Its applicability is demonstrated by testing several well-known benchmarks and large-scale problems, for which SERGHEI-SWE achieves excellent results for the different types of shallow-water problems. Finally, SERGHEI-SWE scalability and performance portability is demonstrated and evaluated on several TOP500 HPC systems, with very good scaling in the range of over 20 000 CPUs and up to 256 state-of-the art GPUs
Heteroptera (hemiptera) species determined in pistachio orchards of Siirt province with a new record for fauna of Turkey: Yotvata nergal Linnavuori, 1993
This study was carried out
at pistachio orchards of Siirt province
(Merkez and Aydınlar) between 2008-2009.
The insect species obtained with this
study in pistachio orchards were;
Palomena mursili Linnavuori, 1984,
Stagonomus bipunctatus Linnaeus, 1758,
Macroscytus brunneus Fabricius, 1803,
Lethaeus cribratissimus Stål, 1858,
Stenodema turanica Reuter, 1904,
Pseudoloxops sangrudanus Linnavuori,
2006 , Psallus perrisi Mulsant and Rey,
1852 Macrolophus glaucescens Fieber,
1858, Acrorrhinium atricorne Linnavuori,
2006, Campylomma diversicornis Reuter,
1878, Nanopsallus carduellus Horváth,
1888, Camptocera glaberrima Walker,
1872, Anthocoris minki Dohrn, 1860,
Yotvata nergal, Alloeotomus cyprius
Wagner, 1953, Calocoris roseomaculatus
angularis De Geer, 1773, Horistus
orientalis Gmelin, 1790, Deraeocoris
serenus Douglas and Scott, 1868, Beosus
quadripunctatus Müller, 1766,
Megalonotus maximus Puton, 1895,
Nysius cymoides Spinola, 1837,
Cantacader quadricornis Lepeletier and
Serville, 1828 , Lethaeus picipes Herrich-
Schäffer, 1853, Acrorrhinium conspersus
Noualhier, 1895, Trigonotylus pulchellus
Hahn, 1834 and Alloeomimus kurdus
Hoberlandt, 1953. Yotvata nergal
Linnavuori, 1993 is a new record for
entomo-fauna of Turkey
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