Search results for "DRAINAGE"
showing 10 items of 381 documents
Assessing sediment connectivity in dendritic and parallel calanchi systems
2019
Abstract Calanchi, a type of Italian badlands created by a combination of water erosion processes and environmental constraints controlling their development, is a striking example of long-term landscape evolution. Sediment connectivity can be defined as the degree to which a system facilitates the fluxes of sediments through itself. The goal of this research is testing the use of simple morphometric variables for assessing sediment connectivity of calanchi landforms distinguishing between dendritic and parallel systems. For detecting the morphological characteristics controlling the sediment connectivity of calanchi basins, literature data (146 calanchi basins) and measurements carried out…
Uncertainty in environmental and hydrological mathematical modelling
2012
The current state of knowledge regarding uncertainties in urban drainage models is poor. This is in part due to the lack of clarity in the way model uncertainty analyses are conducted and how the results are presented and used. There is a need for a common terminology and a conceptual framework for describing and estimating uncertainties in urban drainage models. Practical tools for the assessment of model uncertainties for a range of urban drainage models are also required to be developed. This paper, produced by the International Working Group on Data and Models, which works under the IWA/IAHR Joint Committee on Urban Drainage, is a contribution to the development of a harmonised framewor…
Catchment size and contribution of the largest daily events to suspended sediment load on a continental scale
2013
Abstract The classic approach defines an extreme event as a rare event identified by magnitude–frequency analysis and quantified by its deviation from a central value. They are key to understand geomorphological dynamics, since they are responsible for a considerable amount of work and “time compression”. Time compression means that most of the geomorphic work (particularly sediment transport) is produced in very short temporal intervals (i.e. in few events). Moreover, it is well known from magnitude–frequency analyses that events not necessarily extreme by magnitude could be responsible for a large amount of geomorphic work. To analyse the time compression of geomorphological processes, a …
Long Term Efficiency Analysis of Infiltration Trenches Subjected to Clogging
2018
Abstract: In recent years, limitations linked to traditional urban drainage schemes have been pointed out and new approaches were developed introducing more natural methods for retaining and/or disposing of stormwater. Such practices include infiltration and storage tanks in order to reduce the peak flow and retain part of the polluting components. The impact of such practices on stormwater quantity and quality is not easily assessable because of the complexity of physical and chemical processes involved. In such cases, integrated urban drainage models may play a relevant role providing tools for long term analysis. In this study, the effect of the clogging phenomenon has been assessed by m…
Urban water quality modelling: a parsimonious holistic approach for a complex real case study
2010
In the past three decades, scientific research has focused on the preservation of water resources, and in particular, on the polluting impact of urban areas on natural water bodies. One approach to this research has involved the development of tools to describe the phenomena that take place on the urban catchment during both wet and dry periods. Research has demonstrated the importance of the integrated analysis of all the transformation phases that characterise the delivery and treatment of urban water pollutants from source to outfall. With this aim, numerous integrated urban drainage models have been developed to analyse the fate of pollution from urban catchments to the final receiving …
Suprachoroidal Bleeding After XEN Gel Implantation
2017
Purpose To report for the first time a clinical case of suprachoroidal bleeding after XEN45 gel implantation. Observations A 84-year old female patient with pseudoexfoliation glaucoma with intraocular pressure (IOP) (20 mm Hg) above target despite maximal IOP-lowering therapy was scheduled for XEN45 gel implantation. The XEN45 gel implantation went without complications and was properly placed in the anterior chamber and beneath the conjunctiva. On the first postoperative day, the patient presented with an IOP of 4 mm Hg, a functioning bleb and a deep anterior chamber. On the second day she developed suprachoroidal bleeding. A wait and see strategy was followed and the patient monitored ste…
Soil slope consolidation processes induced by drainage galleries with drainholes
2004
Identification of Potential Locations for Run-of-River Hydropower Plants Using a GIS-Based Procedure
2019
The increasing demand for renewable and sustainable energy sources has encouraged the development of small run-of-river plants. Preliminary studies are required to assess the technical and economic feasibility of such plants. In this context, the identification of optimal potential run-of-river sites has become a key issue. In this paper, an approach that is based on GIS tools coupled with a hydrological model has been applied to detect potential locations for a run-of-river plant. A great number of locations has been analyzed to identify those that could assure the achievement of different thresholds of potential power. The environmental and economic feasibility for small hydropower projec…
Large retroperitoneal abscess extended to the inferior right limb secondary to a perforated ileal Crohn’s disease: the importance of the multidiscipl…
2016
The typical complications of Crohn's disease concerns small and large bowel. The full thickness inflammation of the intestinal wall develops in strictures, fistulas and abdominal abscesses. Nowadays the most accepted therapeutic for intra-abdominal abscess option is antibiotic therapy and, in case of need, percutaneous drainage of the abscess. If the abscess passes through the pelvic foramen the abscess can involve the inferior limbs. We report a case a perforation of terminal ileum in Crohn's disease complicated by a large abscess of the right iliac fossa reaching the spaces between the anterior lateral muscles of the right thigh as far as the anterior lateral pre-tibial region. We discuss…
Exploring Beyond the River and Inside the Valleys: Settlement Development and Cultural Landscape of the Araxes River Basin Through Time
2020
Geographical landmarks, especially rivers, have always played an important role in forming or hampering interplay between societies. In some cases, they act as a “communication route” and in some o...