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Full-Text Articles in Environmental Sciences
A Harmonized Vocabulary For Water Quality, Simon J.D. Cox, Bruce A. Simons, Jonathan Yu
A Harmonized Vocabulary For Water Quality, Simon J.D. Cox, Bruce A. Simons, Jonathan Yu
International Conference on Hydroinformatics
Interoperability of water quality data depends on the use of common models, schemas and vocabularies. However, terms are usually collected during different activities and projects in isolation of one another, resulting in vocabularies that have the same scope being represented with different terms, using different formats and formalisms, and published in various access methods. Significantly, most water quality vocabularies conflate multiple concepts in a single term, e.g. quantity kind, units of measure, substance or taxon, medium and procedure. This bundles information associated with separate elements from the OGC Observations and Measurements (O&M) model into a single slot. We have developed …
Reliability Of Simulated Discharges For Different Gauge Locations In A Semi Distributed Rainfall Runoff Model, Johannes Bellinger, Stefan Achleitner, Johannes Schöber, Friedrich Schöberl
Reliability Of Simulated Discharges For Different Gauge Locations In A Semi Distributed Rainfall Runoff Model, Johannes Bellinger, Stefan Achleitner, Johannes Schöber, Friedrich Schöberl
International Conference on Hydroinformatics
In terms of flood forecasting in alpine environments, predictions at different gauges as well as sites with exposed infrastructure within the catchment are required. The used semi-distributed hydrological model HQsim combines runoff formation and surface runoff routines with an implemented channel routing for river reaches. This allows the estimation of discharges at selected channel segments. As a case study a large alpine catchment with a size of 890 km² is used. The uncertainty in the discharge prediction is investigated at three discharge gauges located along the main river. The basis of our experimental set-up are 15,000 samples describing the prior …
Investigating The Sources Of Fresh Water Affecting The Hydrological Balance Of Lakes Enriquillo And Azuei (Hispaniola) – Data Analysis, Daniel Comarazamy, Jorge Gonzalez, Fred Moshary, Michael Piasecki, Mahrokh Moknatian, John Ibsen
Investigating The Sources Of Fresh Water Affecting The Hydrological Balance Of Lakes Enriquillo And Azuei (Hispaniola) – Data Analysis, Daniel Comarazamy, Jorge Gonzalez, Fred Moshary, Michael Piasecki, Mahrokh Moknatian, John Ibsen
International Conference on Hydroinformatics
The Enriquillo and Azuei are saltwater lakes located in a closed water basin in the southwestern region of the island of La Hispaniola, these have been experiencing dramatic changes in total lake-surface area coverage during the period 1980-2012. The size of Lake Enriquillo presented a surface area of approximately 276 km2 in 1984, gradually decreasing to 172 km2 in 1996. The surface area of the lake reached its lowest point in the satellite observation record in 2004, at 165 km2. Then the recent growth of the lake began reaching its 1984 size by 2006. Based on surface area measurement for …
Direct Numerical Simulation Of Particle Saltation In Turbulent Channel Flow, Chunning Ji, Ante Munjiza, Eldad J. Avital, John J. R. Williams
Direct Numerical Simulation Of Particle Saltation In Turbulent Channel Flow, Chunning Ji, Ante Munjiza, Eldad J. Avital, John J. R. Williams
International Conference on Hydroinformatics
This paper numerically investigates particle saltation in a turbulent channel flow having a rough bed consisting of 2-3 layers of densely packed spheres. The Shield’s Function is 0.065 which is just above the sediment entrainment threshold to give a bed-load regime. The applied methodology is a combination of three technologies, i.e., the direct numerical simulation of turbulent flow, the combined finite-discrete element modelling of the deformation, movement and collision of the particles, and the immersed boundary method for the fluid-solid interaction. It is shown that the presence of entrained particles significantly modifies the flow profiles of velocity, turbulent intensities and …
Weather Generator Tool For The Assessment Of Water Resource Planning In Mediterranean Watersheds, María José Polo, Marta Egüen, Sergio Nieto, Javier Herrero, Asunción Baquerizo, Miguel A. Losada
Weather Generator Tool For The Assessment Of Water Resource Planning In Mediterranean Watersheds, María José Polo, Marta Egüen, Sergio Nieto, Javier Herrero, Asunción Baquerizo, Miguel A. Losada
International Conference on Hydroinformatics
Water resource planning requires the forecasting of precipitation at different time scales that are dependent on the planning horizon for decision making. In Mediterranean areas, the uncertainty associated to precipitation occurrence and amount is very much linked to alternate sequences of highly variable dry and wet pluriannual cycles, and the torrential character of some of the rainfall events within the wet season. Moreover, most of the precipitation is associated to cyclonic fronts passing over the region, and their interaction with the regional and local topography. This work presents a Weather Generator (WG) tool to simulate annual sequences of rainfall events …
Next Generation Hydro Software, Gennadii Donchyts, Fedor Baart, Arthur Van Dam, Erik De Goede, Joost Icke, Hans Van Putten
Next Generation Hydro Software, Gennadii Donchyts, Fedor Baart, Arthur Van Dam, Erik De Goede, Joost Icke, Hans Van Putten
International Conference on Hydroinformatics
A few years ago Deltares started a large multidisciplinary project named Next Generation Hydro Software. The main focus of the project is to improve, harmonize and integrate existing hydro software that has been developed throughout the years. Important technological innovations include development of the new computational core D-Flow Flexible Mesh, as well as the user-friendly, open modelling environment Delta Shell. The project involves more than 40 scientists and software engineers. The new integrated system will allow both water managers and modellers to do their work better and faster. The unique characteristic of the project is that it focuses on the …
Comparison Of Ensemble Kalman Filtering And Particle Filtering On Short-Term Streamflow Forecasting Using A Distributed Hydrologic Model, Seong Jin Noh
International Conference on Hydroinformatics
Floods are the most common and widespread disasters in the world and are responsible for a greater number of damaging events than any other type of natural event. However, due to various uncertainties that originate from simulation models, observations, and forcing data, it is still insufficient to obtain accurate flood forecasting results with the required lead times. Recently, ensemble forecasting techniques based on data assimilation (DA) have become increasingly popular, due to their potential ability to explicitly handle the various sources of uncertainty in operational hydrological models. Difficulty lies in DA for flood forecasting because nonlinearity increases sharply during flood …
Decision Support For Flood Control Operation Of A Multi-Purpose Reservoir Considering Operational One-Week Ensemble Forecast Of Precipitation, Yuya Nishioka, Daisuke Nohara, Tomoharu Hori, Yoshinobu Sato
Decision Support For Flood Control Operation Of A Multi-Purpose Reservoir Considering Operational One-Week Ensemble Forecast Of Precipitation, Yuya Nishioka, Daisuke Nohara, Tomoharu Hori, Yoshinobu Sato
International Conference on Hydroinformatics
atoMulti-purpose reservoirs, which are operated for both of flood control and water use purposes, play an important role in water resources management. Consideration of operational hydrological predictions can potentially provide an improvement in operations of a multi-purpose reservoir by allowing adaptive operation according to the predicted future condition of the reservoir and the target river basin. In this paper, a decision support tool for flood control operation of a multi-purpose reservoir considering middle-range operational ensemble prediction is proposed. One-week Ensemble Forecast of precipitation, which is provided by Japan Meteorological Agency with 51 ensemble members for the coming eight days, is …
Application Of Water Cycle Algorithm For Optimal Cost Design Of Water Distribution Systems, Ali Sadollah, Do Guen Yoo, Jafar Yazdi, Joong Hoon Kim, Younghwan Choi
Application Of Water Cycle Algorithm For Optimal Cost Design Of Water Distribution Systems, Ali Sadollah, Do Guen Yoo, Jafar Yazdi, Joong Hoon Kim, Younghwan Choi
International Conference on Hydroinformatics
Water distribution system (WDS) design is considered as a class of large combinatorial non-linear optimization problems having complex implicit constraints such as conservation of mass and energy equations. Due to the complexity and large feasible solution, traditional optimization techniques are not capable to tackle these kinds of problems. Recently, applications of metaheuristic algorithms, due to their efficiencies and performances, are increased dramatically. In this paper, water cycle algorithm (WCA), a recently developed population-based algorithm, coupled with hydraulic simulator, EPANET, are applied for finding the optimal cost design of WDS. The performance of the WCA is shown using well-known Balerma benchmark …
In-Situ Algae Control Using Water-Lifting Aerators In A Eutrophicated Source Water Reservoir, Xin Sun, Xue Wang, Tinglin Huang, Haibing Cong
In-Situ Algae Control Using Water-Lifting Aerators In A Eutrophicated Source Water Reservoir, Xin Sun, Xue Wang, Tinglin Huang, Haibing Cong
International Conference on Hydroinformatics
Algal pollution is a common water quality problem in many source water reservoirs worldwide and directly threatens the safety of drinking water. Water-lifting aeration has been recently developed to improve the source water quality and to control the excessive algae growth by transporting algae from the surface water to the bottom water of the reservoir. Taking the Shibianyu Reservoir supplying 20% source water to Xi’an, China, as a study case, the effect of in-situ algae control using water-lifting aerators was numerically investigated with Fluent. Two submerged water-lifting aerators with different circulation flow rates were installed with different local water depths …
Propagation Characteristics Of Density Currents And Implications To Pollutant Transport In A Stratified Reservoir, Xin Sun, Yan Xu, Tinglin Huang, Xiao Tang
Propagation Characteristics Of Density Currents And Implications To Pollutant Transport In A Stratified Reservoir, Xin Sun, Yan Xu, Tinglin Huang, Xiao Tang
International Conference on Hydroinformatics
With global warming, the frequency and intensity of extreme rainfall events were predicted to change more dramatically in the near future while the amount of total precipitation will change slightly. Large volume of turbid inflow will enter the source water reservoir after a heavy rainfall, and evolve in various types of density currents depending on the density difference between the inflow and background water. Density currents play an important role in the thermal structure and pollutant transport in the reservoir. Understanding the behaviors of density current is fundamental to study the changes of source water quality during the flooding season. …
A Probabilistic Tsunami Model For Chile, Vaclav Rara, Cristina Arango, Petr Puncochar, Goran Trendafiloski, Chris Ewing, Adam Podlaha, Deepak Vatvani, Maarten Van Ormondt
A Probabilistic Tsunami Model For Chile, Vaclav Rara, Cristina Arango, Petr Puncochar, Goran Trendafiloski, Chris Ewing, Adam Podlaha, Deepak Vatvani, Maarten Van Ormondt
International Conference on Hydroinformatics
In disaster-prone regions such as Chile, catastrophe models help (re)insurers to understand and quantify the risks facing their businesses. The 2010 (M8.8) Maule (Chile) earthquake highlighted the need for quantifying losses not only from primary perils (in this case earthquake) but also from secondary perils such as tsunamis, which contribute to the overall event losses but are not often modelled. This paper presents a new catastrophe model for Chile developed by Impact Forecasting (IF) in collaboration with Aon Benfield Research partners. The model has the capability to model losses due to earthquake (ground-shaking) and induced tsunamis along the Chilean coast …
An Architectural Overview Of Hydroshare, A Next-Generation Hydrologic Information System, Jefferson Heard, David G. Tarboton, Ray Idaszak, Jeffery S. Horsburgh, Dan Ames, Alex Bedig, Anthony M. Castronova, Alva Couch
An Architectural Overview Of Hydroshare, A Next-Generation Hydrologic Information System, Jefferson Heard, David G. Tarboton, Ray Idaszak, Jeffery S. Horsburgh, Dan Ames, Alex Bedig, Anthony M. Castronova, Alva Couch
International Conference on Hydroinformatics
HydroShare is an online, open-source, collaborative system being developed for sharing hydrologic data and models as part of the NSF’s Software Infrastructure for Sustained Innovation (SI2) program. The goal of HydroShare is to enable scientists to easily discover and access hydrologic data and models, retrieve them to their desktop, or perform analyses in a distributed computing environment that may include grid, cloud, or high performance computing. Scientists may also publish outcomes (data, results or models) into HydroShare, using the system as a collaboration platform for sharing data, models, and analyses. HydroShare involves a large distributed software development effort requiring collaboration …
Odm Tools Python: Open Source Software For Managing Continuous Sensor Data, Jeffery S. Horsburgh, Stephanie Reeder, Amber Spackman Jones
Odm Tools Python: Open Source Software For Managing Continuous Sensor Data, Jeffery S. Horsburgh, Stephanie Reeder, Amber Spackman Jones
International Conference on Hydroinformatics
Hydrologic and water quality data is being collected at high frequencies, for extended durations, and with spatial distributions that require infrastructure for data storage and management. The Observations Data Model (ODM), which is part of the Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI) Hydrologic Information System (HIS), was developed as a framework in which to organize, store, and describe point observations data. In this paper we describe ODM Tools Python, which is an open source software application that allows ODM users to query and export, visualize, and edit data stored in an ODM database. Previous versions …