Thematische Bibliographien / Runoff Measurement Mathematical models

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Auswahl der wissenschaftlichen Literatur zum Thema „Runoff Measurement Mathematical models“

Autor: Grafiati
Veröffentlicht am 4. Juni 2021
Zuletzt aktualisiert am 1. Februar 2022

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Zeitschriftenartikel zum Thema "Runoff Measurement Mathematical models"

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Taylor, K., J. A. D. Ranga Niroshan Appuhamy, J. Dijkstra und E. Kebreab. „Development of mathematical models to predict calcium, magnesium and selenium excretion from lactating Holstein cows“. Animal Production Science 58, Nr. 3 (2018): 489. http://dx.doi.org/10.1071/an16307.

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The aim of this study was to develop and evaluate mathematical models that predict mineral excretion, particularly calcium (Ca), magnesium (Mg) and selenium (Se), from lactating dairy cows. Mineral excretion can be affected by several dietary factors. A deficiency in Ca or Mg application to pasture, among other factors, can contribute to grass tetany or wheat pasture poisoning in cows, whereas an excess can cause runoff into water supplies. Manure application with high Se concentration can also result in runoff, causing the bioaccumulation of selenium in aquatic ecosystems, wetland habitats and estuaries, leading to toxic levels in fish. A database composed of studies relating to mineral utilisation in lactating dairy cows conducted after and including the year 2000 was compiled. A meta-analysis was conducted with the aim of creating multiple empirical equations to predict Ca, Mg and Se excretion from lactating dairy cows. Calcium intake, feed Ca content, milk yield, milk protein content and acid detergent fibre content in diet were positively and linearly related to Ca excretion. Dietary crude protein content and milk fat content were negatively related to Ca excretion. Magnesium intake, feed Mg content and milk yield were positively and linearly related to Mg excretion. Selenium content of diet and dry matter intake were linearly and positively related to Se excretion. Two sets of models were developed using or excluding the intake variable and both sets of models were evaluated with independent data originating from commercial herd or individual animals. In general, intake measurements improved prediction when evaluated with independent datasets (root mean square prediction error = 8% to 19% vs 14% to 26% of the average observed value). There were substantial mean biases, particularly those evaluated with data from a commercial farm, perhaps due to inaccurate feed intake measurements. Although there was generally good agreement between predicted and observed mineral excretion, model development and evaluation would benefit from an expanded database.
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Chen, Jiongfeng, und Wan-chang Zhang. „A new numerical model for simulating top surface soil moisture and runoff“. Engineering Computations 35, Nr. 3 (08.05.2018): 1344–63. http://dx.doi.org/10.1108/ec-01-2017-0031.

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PurposeThis paper aims to construct a simplified distributed hydrological model based on the surveyed watershed soil properties database.Design/methodology/approachThe new established model requires fewer parameters to be adjusted than needed by former hydrological models. However, the achieved stream-flow simulation results are similar and comparable to the classic hydrological models, such as the Xinanjiang model and the TOPMODEL.FindingsGood results show that the discharge and the top surface soil moisture can be simultaneously simulated, and that is the exclusive character of this new model. The stream-flow simulation results from two moderate hydrological watershed models show that the daily stream-flow simulation achieved the classic hydrological results shown in the TOPMODEL and Xinanjiang model. The soil moisture validation results show that the modeled watershed scale surface soil moisture has general agreement with the obtained measurements, with a root-mean-square error (RMSE) value of 0.04 (m3/m3) for one of the one-measurement sites and an averaged RMSE of 0.08 (m3/m3) over all measurements.Originality/valueIn this paper, a new simplified distributed hydrological model was constructed.
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Johst, M., S. Uhlenbrook, N. Tilch, B. Zillgens, J. Didszun und R. Kirnbauer. „An attempt of process-oriented rainfall-runoff modeling using multiple-response data in an alpine catchment, Loehnersbach, Austria“. Hydrology Research 39, Nr. 1 (01.02.2008): 1–16. http://dx.doi.org/10.2166/nh.2008.035.

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The development of process-oriented hydrological models, which are able to simulate hydrological processes distributed in space and time, is crucial for optimal management of water resources. The model TACD (tracer aided catchment model, distributed) was modified and applied to the mountainous Loehnersbach catchment (16 km2), Kitzbueheler Alps, Austria, with the aim of simulating the dominant hydrological processes in a distributed way. It can be seen as a further developed, fully distributed version of the HBV-model with a more process-based runoff generation routine, which uses a spatial delineation of hydrological response units (HRUs). Good overall runoff simulations could be obtained for the whole catchment. Additional data, i.e. discharge from sub-catchments, snow height measurements and dissolved silica concentrations, enabled to some extent the evalulation of the simulation of single processes. Certain periods, e.g. short-term runoff fluctuations during snow melt periods, could not be simulated well even when different model modifications were executed. This indicates model shortcomings because of incomplete process understanding and the necessity for further experimental research as well as for new concepts of model structure. In particular, the understanding and mathematical description of subsurface storm flows has to be improved. The impact of different HRU delineations on discharge simulations at the catchment outlet was relatively low, as long as the direct runoff producing units remained constant. However, the impact on runoff predictions at sub-catchment scale was significant. This indicates an ’averaging out’ effect for peculiarities and errors of runoff predictions at larger scales.
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Rosso, R., M. C. Rulli und D. Bocchiola. „Transient catchment hydrology after wildfires in a Mediterranean basin: runoff, sediment and woody debris“. Hydrology and Earth System Sciences 11, Nr. 1 (17.01.2007): 125–40. http://dx.doi.org/10.5194/hess-11-125-2007.

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Abstract. The transient effect of forest fires on runoff, erosion and yield of woody biomass has been investigated by combining the experimental approach with mathematical models of hydrological processes. The case study is the Branega creek in Liguria, Italy, where a forest fire in August 2003 caused substantial changes to soil and vegetation, and left a considerable amount of woody debris on the ground. Immediately after the fire, rainfall simulator experiments in adjacent burned and unburned plots showed the extent to which fire had increased runoff and erosion rates. A distributed hydrological model using the tube-flux approach, calibrated on experimental measurements, has been used to investigate hill slope and channel erosion in a small sub-catchment, 1.5 ha in area, nested in the Branega basin. Simulation runs show that the model accommodates the observed variability of runoff and erosion under disturbed and undisturbed conditions. A model component describing the delivery of wood from hill slopes to the channel in post-fire conditions, validated against local survey data, showed that the removal and transport of woody biomass can be reproduced using an integrated hydrological approach. Hence, transient complexity after wildfires can be addressed by such an approach with empirically determined physically-based parameters.
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Svetlitchnyi, А. A., und A. V. Piatkova. „Spatially distributed GIS-realized mathematical model of rainstorm erosion losses of soil“. Journal of Geology, Geography and Geoecology 28, Nr. 3 (10.10.2019): 562–71. http://dx.doi.org/10.15421/111953.

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In connection with the wide and ever increasing spread of erosion degradation of agricultural lands in Ukraine, the task of developing mathematical models and methods for calculating water erosion of soils corresponding to the current level of erosion study and the demands of soil protection practices is becoming increasingly important. The article is devoted to the development of a spatially distributed GIS-implemented mathematical model of rainstorm soil erosion, which accounts for most of the annual soil losses (in the Steppe zone, for example, about 90 %). The development of the model is based on the most theoretically and informationally grounded model for the Steppe and Forest-Steppe of Ukraine , “the logical-mathematical model of rainstorm soil outwash” developed by H. I. Shvebs (1974, 1981), as well as the results of theoretical and field studies and mathematical modeling of the slope runoff and water erosion of soil, carried out at the Department of Physical Geography and Environmental Management of Odessa I. I. Mechnikov National University in the 1990s - 2010s, and also the possibilities of modern geoinformation technologies. For the spatial implementation of the model, a raster model of spatial data and operators of the PCRaster GIS-package (University of Utrecht, the Netherlands) were used, integrated with the Basic programming language into a single system that provides an implementation of the computational algorithm. The developed physical-statistical model of soil erosion-sedimentation takes into account the peculiarities of the formation of slope runoff and soil outwash in conditions of excessive nonstationarity of heavy rainfall, as well as spatial heterogeneity of all major natural and economic factors of water erosion on a slope, including slope steepness, exposure, longitudinal and transverse forms of slopes, soil erodibility, structure of sown areas and anti-erosion measures. Checking the adequacy of the mathematical model was performed using observational data of four experimental catchments ; two runoff plots of the Moldavan water-balance station with total area of 0.08 ha, the Ploska catchment with area of 8.5 ha (Boguslav field experimental base of Ukrainian Hydrometeorological Institute) and the Sukha catchment with area of 63 ha (Veliko-Anadol water-balance station) with observation periods of 17-31 years. Comparison of the calculated average over the catchment area of mean annual values of rainstorm soil losses, with the corresponding values obtained from measurements on these catchments, made on the basis of Nash-Sutcliff efficiency criterion (NS), allowed us to evaluate the quality of the model as good (NS = 0.72).
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Djordjević, S., D. Prodanović, Č. Maksimović, M. Ivetić und D. Savić. „SIPSON – Simulation of Interaction between Pipe flow and Surface Overland flow in Networks“. Water Science and Technology 52, Nr. 5 (01.09.2005): 275–83. http://dx.doi.org/10.2166/wst.2005.0143.

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The new simulation model, named SIPSON, based on the Preissmann finite difference method and the conjugate gradient method, is presented in the paper. This model simulates conditions when the hydraulic capacity of a sewer system is exceeded, pipe flow is pressurized, the water flows out from the piped system to the streets, and the inlets cannot capture all the runoff. In the mathematical model, buried structures and pipelines, together with surface channels, make a horizontally and vertically looped network involving a complex interaction of flows. In this paper, special internal boundary conditions related to equivalent inlets are discussed. Procedures are described for the simulation of manhole cover loss, basement flooding, the representation of street geometry, and the distribution of runoff hydrographs between surface and underground networks. All these procedures are built into the simulation model. Relevant issues are illustrated on a set of examples, focusing on specific parameters and comparison with field measurements of flooding of the Motilal ki Chal catchment (Indore, India). Satisfactory agreement of observed and simulated hydrographs and maximum surface flooding levels is obtained. It is concluded that the presented approach is an improvement compared to the standard “virtual reservoir” approach commonly applied in most of the models.
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Ellis, Kathryn K., Timothy Callahan, Dianne I. Greenfield, Denise Sanger, Joshua Robinson und Martin Jones. „Measuring and Modeling Flow Rates in Tidal Creeks: A Case Study from the Central Coast of South Carolina“. Journal of South Carolina Water Resources, Nr. 4 (01.06.2017): 21–39. http://dx.doi.org/10.34068/jscwr.04.03.

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The purpose of this study was to collect site- and condition-specific hydrology data to better understand the water flow dynamics of tidal creeks and terrestrial runoff from surrounding watersheds. In this paper, we developed mathematical models of tidal creek flow (discharge) in relation to time during a tidal cycle and also estimated terrestrial runoff volume from design storms to compare to tidal creek volumes. Currently, limited data are available about how discharge in tidal creeks behaves as a function of stage or the time of tide (i.e., rising or falling tide) for estuaries in the southeastern United States, so this information fills an existing knowledge gap. Ultimately, findings from this study will be used to inform managers about numeric nutrient criteria (nitrogen-N and phosphorus-P) when it is combined with biological response (e.g., phytoplankton assemblages) data from a concurrent study. We studied four tidal creek sites, two in the Ashepoo-Combahee-Edisto (ACE) Basin and two in the Charleston Harbor system. We used ArcGIS to delineate two different watersheds for each study site, to classify the surrounding land cover using the NOAA Coastal Change Analysis Program (C-CAP) data, and to analyze the soils using the NRCS Soil Survey Geographic database (SSURGO). The size of the U.S. Geological Survey’s Elevation Derivatives for National Application (EDNA) watersheds varied from 778 to 2,582 ha; smaller geographic watersheds were delineated for all sites (except Wimbee) for stormwater modeling purposes. The two sites in Charleston Harbor were within the first-order Horlbeck Creek and the second-order Bulls Creek areas. The ACE Basin sites were within the third-order Big Bay Creek and the fourth-order Wimbee Creek areas. We measured the stage and discharge in each creek with an acoustic Doppler current profiler (ADCP) unit for multiple tide conditions over a 2-year period (2015–2016) with the goal of encompassing as large of a range of tide stage and discharge data measurements as possible. The Stormwater Runoff Modeling System (SWARM) was also used to estimate the potential water entering the creeks from the land surface; this volume was very small relative to the tide water volume except for the more-developed Bulls Creek watershed. The results show that the peak discharge occurred on the ebb tide and that the duration of the flood tide spanned a longer period of time; both of these observations are consistent with traits associated with an ebb-dominated tidal creek system. The tidal inflow and outflow (flood and ebb tides, respectively) showed an asymmetrical pattern with respect to stage and discharge; peak discharge during the flood (rising) tide occurred at a higher stage than for the peak discharge during the ebb (falling) tide. This is not an unexpected result, as the water on an ebb tide is moving down gradient funneled through the creek channel toward the coast. Furthermore, water moving with the rising flood tide must overcome frictional losses due to the marsh bank and vegetation; i.e., the peak discharge can only happen when the water has risen above these impediments. We infer from the flow dynamics data that faster water velocities during ebb tide imply that more erosive energy could transport a larger mass of suspended solids and associated nutrients (e.g., orthophosphate) from the estuary to the coastal ocean. However, the discharge and runoff modeling indicate that land-based flux was important in the developed Bulls Creek watershed, but not at the larger and less-developed Big Bay Creek watershed. At Big Bay Creek, the relatively large tidal discharge volume compared to the smaller potential runoff generated within the watershed indicates that the creek could potentially dilute terrestrial runoff contaminants. Smaller, more-urbanized tidal wetland systems may not benefit from such dilution effects and thus are vulnerable to increased runoff from adjacent developed landscapes.
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Mańko, Robert, und Norbert Laskowski. „Comparative analysis of the effectiveness of the conceptual rainfall-runoff hydrological models on the selected rivers in Odra and Vistula basins“. ITM Web of Conferences 23 (2018): 00025. http://dx.doi.org/10.1051/itmconf/20182300025.

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Identification of physical processes occurred in the watershed is one of the main tasks in hydrology. Currently the most efficient hydrological processes describing and forecasting tool are mathematical models. They can be defined as a mathematical description of relations between specified attributes of analysed object. It can be presented by: graphs, arrays, equations describing functioning of the object etc. With reference to watershed a mathematical model is commonly defined as a mathematical and logical relations, which evaluate quantitative dependencies between runoff characteristics and factors, which create it. Many rainfall-runoff linear reservoirs conceptual models have been developed over the years. The comparison of effectiveness of Single Linear Reservoir model, Nash model, Diskin model and Wackermann model is presented in this article.
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Ebrahimian, H., und A. Liaghat. „Field evaluation of various mathematical models for furrow and border irrigation systems“. Soil and Water Research 6, No. 2 (30.05.2011): 91–101. http://dx.doi.org/10.17221/34/2010-swr.

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In this study, three mathematical models in the SIRMOD package including the hydrodynamic (HD), zero inertia (ZI), and kinematic wave (KW) models were tested using the data from several field experiments for both border and furrow irrigation systems. Five data sets for borders and seven data sets for furrows were used in this assessment. The results indicated that the performance of all models was satisfactory for the prediction of the advance and recession times. There was no difference in the prediction of the advance and recession times and infiltrated and runoff volumes between the hydrodynamic and zero-inertia approaches of the SIRMOD software. The HD, ZI, and KW models predicted the recession times better than the advance times for both the experimental borders and furrows. The predicted advance and recession times were estimated by these models more accurately than the infiltrated and runoff volumes. Also the accuracy of these models for the prediction of the advance and recession times was better for the experimental furrows in comparison with the experimental borders.
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Stentsel, Y., O. Porkuian, K. Litvinov und T. Sotnikova. „Mathematical Models of Additional Measurement Errors of Control Means“. Metrology and instruments, Nr. 2 (03.05.2019): 43–51. http://dx.doi.org/10.33955/2307-2180(2)2019.43-51.

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Studies have shown that under industrial conditions there is rarely a correction of the current measurement result when the influencing parameter deviates from the normalized value. The existing method of determining the additional measurement error is that in order to obtain the real value of the measurement result, the correction is calculated, which leads to the current value of indexes of control means. The correction value is determined by dividing the degree of the influencing parameter deviation by the normalized value of the additional error. This method of determining the correction is not accurate enough, since it does not take into account the nonlinear dependence of the additional measurement error on the change in the influencing parameter, as well as on the current value of the output signal of control means. To determine the real value of the measured parameter and the additional error, the method of integral-type functional is proposed. The essence of the method is in determining the difference of planes under the nominal and current parts of the static characteristic, limited by the measurement range. It is shown that the planes difference depends on the current and real values of the output signal of control means, as well as on the influencing parameter deviation. The method allows calculating the real values of the measured parameter only by the output signal of control means and the current values of the influencing parameter. The dependencies between the real value of the measured parameter, the current value of the output signal of control means and the influencing parameter deviation are established.
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Dissertationen zum Thema "Runoff Measurement Mathematical models"

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Sorooshian, Soroosh, und Vijai Kumar Gupta. „Improving the Reliability of Compartmental Models: Case of Conceptual Hydrologic Rainfall-Runoff Models“. Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1986. http://hdl.handle.net/10150/614011.

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Hendrickson, Jene Diane, und Soroosh Sorooshian. „CALIBRATION OF RAINFALL-RUNOFF MODELS USING GRADIENT-BASED ALGORITHMS AND ANALYTIC DERIVATIVES“. Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1987. http://hdl.handle.net/10150/614186.

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In the past, derivative-based optimization algorithms have not frequently been used to calibrate conceptual rainfall -riff (CRR) models, partially due to difficulties associated with obtaining the required derivatives. This research applies a recently- developed technique of analytically computing derivatives of a CRR model to a complex, widely -used CRR model. The resulting least squares response surface was found to contain numerous discontinuities in the surface and derivatives. However, the surface and its derivatives were found to be everywhere finite, permitting the use of derivative -based optimization algorithms. Finite difference numeric derivatives were computed and found to be virtually identical to analytic derivatives. A comparison was made between gradient (Newton- Raphsoz) and direct (pattern search) optimization algorithms. The pattern search algorithm was found to be more robust. The lower robustness of the Newton-Raphsoi algorithm was thought to be due to discontinuities and a rough texture of the response surface.
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Price, Myra Ann. „Seasonal Variation in Runoff Curve Number“. Thesis, The University of Arizona, 1998. http://hdl.handle.net/10150/225411.

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The seasonal variation in rainfall - runoff response is investigated for about 300 small watersheds throughout the United States. Data from USDA research watersheds were used to define runoff Curve Number for ordered data sets by months. Three major patterns of cyclic variation are found and investigated: 1) distinct and well - defined seasonal variations as typified by forested watersheds in heavy rainfall zones; 2) mildly cyclic variation found typically in meadows and grasslands, and 3) non - cyclic or unidentifiable patterns, including those with insufficient seasonal data. The only pattern that may be present is the well-defined seasonal variation found so far only in forested watersheds. Regional characteristics were found for individual crop types. For the watersheds studied there seemed to be no difference in the variation between crops except for meadow during the summer. Some associated background factors are explored, including long-term and short-term antecedent rainfall.
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Kapangaziwiri, Evison. „Regional application of the Pitman monthly rainfall-runoff model in Southern Africa incorporating uncertainty“. Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1006178.

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Climate change and a growing demand for freshwater resources due to population increases and socio-economic changes will make water a limiting factor (in terms of both quantity and quality) in development. The need for reliable quantitative estimates of water availability cannot be over-emphasised. However, there is frequently a paucity of the data required for this quantification as many basins, especially in the developing world, are inadequately equipped with monitoring networks. Existing networks are also shrinking due mainly to shortages in human and financial resources. Over the past few decades mathematical models have been used to bridge the data gap by generating datasets for use in management and policy making. In southern Africa, the Pitman monthly rainfall-runoff model has enjoyed relatively popular use as a water resources estimation tool. However, it is acknowledged that models are abstractions of reality and the data used to drive them is imperfect, making the model outputs uncertain. While there is acknowledgement of the limitations of modelled data in the southern African region among water practitioners, there has been little effort to explicitly quantify and account for this uncertainty in water resources estimation tools and explore how it affects the decision making process. Uncertainty manifests itself in three major areas of the modelling chain; the input data used to force the model, the parameter estimation process and the model structural errors. A previous study concluded that the parameter estimation process for the Pitman model contributed more to the global uncertainty of the model than other sources. While the literature abounds with uncertainty estimation techniques, many of these are dependent on observations and are therefore unlikely to be easily applicable to the southern African region where there is an acute shortage of such data. This study focuses on two aspects of making hydrologic predictions in ungauged basins. Firstly, the study advocates the development of an a priori parameter estimation process for the Pitman model and secondly, uses indices of hydrological functional behaviour to condition and reduce predictive uncertainty in both gauged and ungauged basins. In this approach all the basins are treated as ungauged, while the historical records in the gauged basins are used to develop regional indices of expected hydrological behaviour and assess the applicability of these methods. Incorporating uncertainty into the hydrologic estimation tools used in southern Africa entails rethinking the way the uncertain results can be used in further analysis and how they will be interpreted by stakeholders. An uncertainty framework is proposed. The framework is made up of a number of components related to the estimation of the prior distribution of the parameters, used to generate output ensembles which are then assessed and constrained using regionalised indices of basin behavioural responses. This is premised on such indices being based on the best available knowledge covering different regions. This framework is flexible enough to be used with any model structure to ensure consistent and comparable results. While the aim is to eventually apply the uncertainty framework in the southern African region, this study reports on the preliminary work on the development and testing of the framework components based on South African basins. This is necessitated by the variations in the availability and quality of the data across the region. Uncertainty in the parameter estimation process was incorporated by assuming uncertainty in the physical and hydro-meteorological data used to directly quantify the parameter. This uncertainty was represented by the range of variability of these basin characteristics and probability distribution functions were developed to account for this uncertainty and propagate it through the estimation process to generate posterior distributions for the parameters. The results show that the framework has a great deal of potential but can still be improved. In general, the estimated uncertain parameters managed to produce hydrologically realistic model outputs capturing the expected regimes across the different hydro-climatic and geo-physical gradients examined. The regional relationships for the three indices developed and tested in this study were in general agreement with existing knowledge and managed to successfully provide a multi-criteria conditioning of the model output ensembles. The feedback loop included in the framework enabled a systematic re-examination of the estimation procedures for both the parameters and the indices when inconsistencies in the results were identified. This improved results. However, there is need to carefully examine the issues and problems that may arise within other basins outside South Africa and develop guidelines for the use of the framework.
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Pokhrel, Pranav. „The Study of Temporal and Spatial Variability of Degree Day Factor of Snowmelt in Colorado“. Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc849730/.

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Snowmelt is one of the major sources of surface water supply and ground-water recharge in high elevation areas and can also cause flooding in snow dominated watersheds. Direct estimation of daily snowmelt requires daily snow water equivalent (SWE) measurements that are not always available, especially in places without monitoring stations. There are two alternative approaches to modeling snowmelt without using direct measurements of SWE, temperature-based and energy-based models. Due to its simplicity, computational efficiency, and less input data requirement, the temperature-based method is commonly used than the energy-based method. In the temperature-index approach snowmelt is estimated as a linear function of average air temperature, and the slope of the linear function is called the degree-day factor (DDF). Hence, the DDF is an essential parameter for utilizing the temperature-based method to estimate snowmelt. Thereby, to analyze the spatial properties of DDF, 10 years DDF from the entire state of Colorado was calculated for this research. Likewise, to study the temporal properties, DDFs for 27 years from the White Yampa water basin and the Colorado Headwaters water basin were calculated. As a part of the spatial analysis, the calculated DDFs were correlated with spatial variables (slope, aspect, latitude and elevation) and a spatial correlation graph was created to observe the possibility of predicting DDF. Also a multivariate regression model was prepared using these spatial variables to predict the DDF using spatial variables. Further, the DDFs calculated from Colorado headwaters and the White Yampa water basins were correlated for annual temporal variation, daily variation, variation with peak snow water equivalent and variation with important temporal cycles like accumulation period and melting period of snowmelt. The result obtained from this study showed that the variability of DDF is more dependent upon temporal factors compared to the spatial factors. Also, the results showed that predicting DDF is a difficult process and requires complex methods than simple linear models or multivariate models.
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Galarraga, Sanchez Remigio Hernan. „Scale effects in determining snowmelt from mountainous basins using a distributed approach for snow water equivalence and radiation, and a point snowmelt model“. Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/191186.

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Rates of snowmelt distributed across Emerald Lake watershed, an alpine basin located in the Sierra Nevada, California, were estimated for water year 1987 using a point snowmelt model applied to regions that were classified based on distributed snow water equivalence and net solar radiation (NSR). A 5-m resolution digital elevation model (DEM) and a 5-m classified digital terrain model of snow water equivalence (SWE) were resampled to coarser resolutions (25-m, 30-m, 50-m, and 100-m) using the nearest neighbor approach. These images were used to define other snowmelt physical parameters and the initial state of the snowpack before melting. Topographic parameters calculated at 50-m and 100-m resolution exhibited significant differences in their histogram distribution as compared to the 5-m DEM. The most important were variations in slope, aspect, sky view factor, and terrain configuration factor, which influenced radiation calculations and the definition of distributed parameters for snowmelt calculations. Elevations, however, did not change significantly from one resolution to the other. The distribution of topographic parameters modeled at 25-m and 30-m, remained almost unchanged. Four, seven and ten classes of snow water equivalence and net solar radiation were combined using a band interleave process to determine the maximum number of combined classes. The point snowmelt model was then applied to these areas, which shared similar SWE and NSR characteristics, to obtain hourly melt rates. Modeled snowmelt rates were compared to the total daily discharge observed at the outlet of Emerald Lake watershed. There was good agreement for resolutions S-, 25-, 30-, and 50-m but not for the 100-m OEM, as modeled net solar radiation was too high and water was released from the basin too early. Model performance using three tests (Nash-Sutcliffe criteria, sum of squares of the deviations and the sum of the absolute differences between observed discharge and computed melting) showed that the 30-m resolution OEM with combined classes of 7 SWE and 7 NSR provided the best snowmelt performance for this distributed approach. Finally, fractional snow cover area at one month intervals were estimated, showing that this approach offers the potential to model spatially distributed snow covered area in alpine regions.
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Goodrich, David Charles. „Basin Scale and Runoff Model Complexity“. Department of Hydrology and Water Resources, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/614028.

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Distributed Rainfall-Runoff models are gaining widespread acceptance; yet, a fundamental issue that must be addressed by all users of these models is definition of an acceptable level of watershed discretization (geometric model complexity). The level of geometric model complexity is a function of basin and climatic scales as well as the availability of input and verification data. Equilibrium discharge storage is employed to develop a quantitative methodology to define a level of geometric model complexity commensurate with a specified level of model performance. Equilibrium storage ratios are used to define the transition from overland to channel -dominated flow response. The methodology is tested on four subcatchments in the USDA -ARS Walnut Gulch Experimental Watershed in Southeastern Arizona. The catchments cover a range of basins scales of over three orders of magnitude. This enabled a unique assessment of watershed response behavior as a function of basin scale. High quality, distributed, rainfall -runoff data was used to verify the model (KINEROSR). Excellent calibration and verification results provided confidence in subsequent model interpretations regarding watershed response behavior. An average elementary channel support area of roughly 15% of the total basin area is shown to provide a watershed discretization level that maintains model performance for basins ranging in size from 1.5 to 631 hectares. Detailed examination of infiltration, including the role and impacts of incorporating small scale infiltration variability in a distribution sense, into KINEROSR, over a range of soils and climatic scales was also addressed. The impacts of infiltration and channel losses on runoff response increase with increasing watershed scale as the relative influence of storms is diminished in a semiarid environment such as Walnut Gulch. In this semiarid environment, characterized by ephemeral streams, watershed runoff response does not become more linear with increasing watershed scale but appears to become more nonlinear.
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Kapangaziwiri, Evison. „Revised parameter estimation methods for the Pitman monthly rainfall-runoff model“. Thesis, Rhodes University, 2008. http://hdl.handle.net/10962/d1006172.

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In recent years, increased demands have been placed on hydrologists to find the most effective methods of making predictions of hydrologic variables in ungauged basins. A huge part of the southern African region is ungauged and, in gauged basins, the extent to which observed flows represent natural flows is unknown, given unquantified upstream activities. The need to exploit water resources for social and economic development, considered in the light of water scarcity forecasts for the region, makes the reliable quantification of water resources a priority. Contemporary approaches to the problem of hydrological prediction in ungauged basins in the region have relied heavily on calibration against a limited gauged streamflow database and somewhat subjective parameter regionalizations using areas of assumed hydrological similarity. The reliance of these approaches on limited historical records, often of dubious quality, introduces uncertainty in water resources decisions. Thus, it is necessary to develop methods of estimating model parameters that are less reliant on calibration. This thesis addresses the question of whether physical basin properties and the role they play in runoff generation processes can be used directly in the estimation of parameter values of the Pitman monthly rainfall-runoff model. A physically-based approach to estimating the soil moisture accounting and runoff parameters of a conceptual, monthly time-step rainfall-runoff model is proposed. The study investigates the physical meaning of the model parameters, establishes linkages between parameter values and basin physical properties and develops relationships and equations for estimating the parameters taking into account the spatial and temporal scales used in typical model applications. The estimationmethods are then tested in selected gauged basins in southern Africa and the results of model simulations evaluated against historical observed flows. The results of 71 basins chosen from the southern African region suggest that it is possible to directly estimate hydrologically relevant parameters for the Pitman model from physical basin attributes. For South Africa, the statistical and visual fit of the simulations using the revised parameters were at least as good as the current regional sets, albeit the parameter sets being different. In the other countries where no regionalized parameter sets currently exist, simulations were equally good. The availability, within the southern African region, of the appropriate physical basin data and the disparities in the spatial scales and the levels of detail of the data currently available were identified as potential sources of uncertainty. GIS and remote sensing technologies and a widespread use of this revised approach are expected to facilitate access to these data.
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Luckemeier, Richard Ewald 1948. „A rainfall-runoff model for an urban watershed in Tucson, Arizona“. Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277165.

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The U.S. Geological Survey and the City of Tucson, Arizona, have been collecting rainfall and runoff data on several watersheds in the Tucson area for several years. Among the purposes of this project is to use the data to test rainfall-runoff models in an effort to find one to successfully simulate flood flows in Tucson. One such model, the Distributed Routing Rainfall-Runoff Model (DR3M), was tested using data collected on Rob Wash in Tucson. It was found DR3M performs about as well as it does in other parts of the United States, although it tends to underestimate flood flows for large storms and overestimate flows for smaller storms. Unique features with regard to the hydrology of urban Tucson require special attention when using DR3M; these features are associated with the nature of dry washes and summer rainfall in Tucson. Experience indicates DR3M is not truly a deterministic model.
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Koterba, Michael T. „Differential influences of storm and watershed characteristics on runoff from ephemeral streams in southeastern Arizona“. Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/191126.

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Relationships between thunderstorm and watershed variables and runoff from or within semiarid watersheds at Walnut Gulch, Arizona were examined. Variables showing greater sensitivity to basin and storm size were better flow predictors. Stepwise regression with three increasingly nonlinear algebraic models showed mean storm depth was the best simple predictor of runoff. Predictions improved using storm volume, a product of storm depth and areal extent. Initial runoff to streams was best described as a highly nonlinear function of storm and watershed variables. Runoff from a basin was a more linearized function of similar variables. The above differences were ascribed to channel transmission losses, reductions in runoff moving down initially dry channels. For a given basin and small storms, loss to runoff ratios exceeded 10:1 and were highly variable. Ratios were similar and less than 0.5:1 for storms centrally located over a basin and generating sufficient initial runoff to minimize flow variation due to losses. Losses increased disproportionately with basin size. Antecedent rainfall and first summer flows also affected rainfall runoff relationships in a differential manner. Wet conditions enhanced runoff more from larger versus smaller storms. First summer flows were less than expected probably because of higher soil infiltration and channel losses at the onset of summer storms. Overall, as storm size decreased or basin area increased, initial runoff was more often a localized phenomenon and downstream flow more dependent on storm depth, extent, location, and seasonal timing and basin channel losses, but less dependent on antecedent rainfall. Consequently, storm depth accounted for only 60% to 70% of the variation in flows while storm volume, antecedent rainfall, channel losses, and first summer flows explained 80% to 90%. Finally, oversimplifying storm or watershed variables or analytical methods led to errors in assessing their affect on runoff. It was also determined that current arguments supporting a recommendation to delete smaller, frequent annual floods to better fit remaining data to flood frequency curves were oversimplified. Distributed rainfall - runoff models with channel losses and regional storm depth - area - frequency data may be the way to develope flood curves for semiarid basins with short runoff records.
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Bücher zum Thema "Runoff Measurement Mathematical models"

1

Croley, Thomas E. Modified Great Lakes hydrology modeling system for considering simple extreme climates. Ann Arbor, Mich: U.S. Dept. of Commerce, National Oceanic and Atmospheric Administration, Great Lakes Environmental Research Laboratory, 2006.

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Zarriello, Phillip J. A precipitation-runoff model for the analysis of the effects of water withdrawals and land-use change on streamflow in the Usquepaug-Queen River Basin, Rhode Island. Reston, Va: U.S. Dept. of the Interior, U.S. Geological Survey, 2004.

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Mazvimavi, Dominic. Estimation of flow characteristics of ungauged catchments: Case study in Zimbabwe. [Enschede]: ITC, 2003.

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Wong, Tommy S. W. Overland flow and surface runoff. Hauppauge, N.Y: Nova Science Publishers, 2011.

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Lanning-Rush, Jennifer. Regional equations for estimating mean annual and mean seasonal runoff for natural basins in Texas, base period 1961-90. Austin, Tex: U.S. Dept. of the Interior, U.S. Geological Survey, 2000.

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Lanning-Rush, Jennifer. Regional equations for estimating mean annual and mean seasonal runoff for natural basins in Texas, base period 1961-90. Austin, Tex: U.S. Dept. of the Interior, U.S. Geological Survey, 2000.

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Cary, Lawrence E. Techniques for estimating selected parameters of the U.S. Geological Survey's Precipitation-Runoff Modeling System in eastern Montana and northeastern Wyoming. Helena, Mont: U.S. Dept. of the Interior, U.S. Geological Survey, 1991.

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Heeswijk, Marijke van. Development of a precipitation-runoff model to simulate unregulated streamflow in the Salmon Creek Basin, Okanogan County, Washington. Reston, Va: U.S. Dept. of the Interior, U.S. Geological Survey, 2006.

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Huber, Wayne Charles. The USEPA SWMM4 Stormwater Management Model: Version 4 user's manual. Guelph, Ont: University of Guelph, School of Engineering, 1989.

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Ely, D. Matthew. Precipitation-runoff simulations of current and natural streamflow conditions in the Methow River basin, Washington. Tacoma, Wash: U.S. Dept. of the Interior, U.S. Geological Survey, 2003.

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Buchteile zum Thema "Runoff Measurement Mathematical models"

1

Lomba, Jaime Terceiro. „Formulation of Econometric Models with Measurement Errors“. In Lecture Notes in Economics and Mathematical Systems, 17–23. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-48810-8_3.

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Lomba, Jaime Terceiro. „Estimation of Econometric Models with Measurement Errors“. In Lecture Notes in Economics and Mathematical Systems, 24–48. Berlin, Heidelberg: Springer Berlin Heidelberg, 1990. http://dx.doi.org/10.1007/978-3-642-48810-8_4.

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Zeman, E., und J. Spatka. „Evaluation of Impacts of Control Measures, Applied in the Source Catchments, by Mathematical Models“. In Advances in Urban Stormwater and Agricultural Runoff Source Controls, 181–94. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-0532-6_16.

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Whitney, Hassler. „The Mathematics of Physical Quantities Part I: Mathematical Models for Measurement“. In Hassler Whitney Collected Papers, 530–83. Boston, MA: Birkhäuser Boston, 1992. http://dx.doi.org/10.1007/978-1-4612-2974-2_36.

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Elitzur, Avshalom C. „Time Anisotropy and Quantum Measurement: Clues for Transcending the Geometric Picture of Time“. In Modern Mathematical Models of Time and their Applications to Physics and Cosmology, 313–19. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-011-5628-8_26.

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Miroshnichenko, I. P., I. A. Parinov, E. V. Rozhkov und S. H. Chang. „Mathematical Models, Program Software, Technical and Technological Solutions for Measurement of Displacements of the Control Object Surfaces by Laser Interferometer“. In Springer Proceedings in Physics, 341–56. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-26324-3_24.

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Muirhead, P. M. P. „The Measurement and Assessment of some Critical Skills of Mariners on CGI Shiphandling Simulators. Can the Mathematical Models meet the Demand?“ In Maritime Simulation, 254–63. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-82560-6_23.

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„Preferences-Based Performance Measurement Models“. In Decision Control, Management, and Support in Adaptive and Complex Systems, 62–84. IGI Global, 2013. http://dx.doi.org/10.4018/978-1-4666-2967-7.ch003.

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It is shown that the human subjective expectations for the uncertainty events can be described mathematically with the terms of the probability theory and can be inserted into the mathematical theory of von Neumann and Morgenstern. Some examples of utility functions are shown.
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Zahran, El-Said Mamdouh Mahmoud. „A Mathematical Approach to Enhance the Performance of Air Pollution Models“. In Air Quality - Measurement and Modeling. InTech, 2016. http://dx.doi.org/10.5772/64758.

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„Drobot's Dimensional Space and a Classical Theory of Measurement“. In Dimensional Analysis in the Identification of Mathematical Models, 1–11. WORLD SCIENTIFIC, 1990. http://dx.doi.org/10.1142/9789814366427_0001.

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Konferenzberichte zum Thema "Runoff Measurement Mathematical models"

1

Fahim, Tahasin Ahmed, und Md Shamim Anower. „Mathematical Models for Fat Free Mass Measurement Based on Bioelectrical Impedance Analysis“. In 2019 1st International Conference on Advances in Science, Engineering and Robotics Technology (ICASERT). IEEE, 2019. http://dx.doi.org/10.1109/icasert.2019.8934477.

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Svaic, Srecko, und Igor Sundov. „Mathematical models for simulation of cooling processes using infrared surface-temperature measurement“. In SPIE's 1995 Symposium on OE/Aerospace Sensing and Dual Use Photonics, herausgegeben von Sharon A. Semanovich. SPIE, 1995. http://dx.doi.org/10.1117/12.204876.

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Radhika, T. S. L., und M. B. Srinivas. „Evaluation of mathematical models for estimation of arterial stiffness through pulse transit time measurement“. In 2014 Health Innovations and POCT. IEEE, 2014. http://dx.doi.org/10.1109/hic.2014.7038913.

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Khatun, Mst Farzana, Md Sohel Rana, Tahasin Ahmed Fahim und Syed Tauhid Zuhori. „Mathematical Models for Extracellular Fluid Measurement to Detect Hydration Level Based on Bioelectrical Impedance Analysis“. In 2019 IEEE Canadian Conference of Electrical and Computer Engineering (CCECE). IEEE, 2019. http://dx.doi.org/10.1109/ccece.2019.8861841.

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Grishko, Aleksey K., Nikolai V. Goryachev, Igor I. Kochegarov und Michail P. Kalaev. „Mathematical models of the system of measurement and analysis of temperature parameters of radio electronic modules“. In 2016 13th International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE). IEEE, 2016. http://dx.doi.org/10.1109/apeie.2016.7806424.

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Grishko, A. K., N. V. Goryachev, I. I. Kochegarov und M. P. Kalaev. „Mathematical models of the system of measurement and analysis of temperature parameters of radio electronic modules“. In 2016 13th International Scientific-Technical Conference on Actual Problems of Electronics Instrument Engineering (APEIE). IEEE, 2016. http://dx.doi.org/10.1109/apeie.2016.7806896.

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Crescencio, J. C., L. E. B. Martins, L. O. Murta, C. M. Antloga, R. T. Kozuki, M. D. B. Santos, J. A. Marin Neto, B. C. Maciel und L. Gallo. „Measurement of anaerobic threshold during dynamic exercise in healthy subjects: comparison among visual analysis and mathematical models“. In Computers in Cardiology, 2003. IEEE, 2003. http://dx.doi.org/10.1109/cic.2003.1291278.

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Ivankova, T. V., und V. A. Volosukhin. „CALCULATION OF THE PASSAGE OF FLOODS THROUGH THE WATERWORKS BALANOVSKY RESERVOIR“. In STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS. DSTU-PRINT, 2020. http://dx.doi.org/10.23947/interagro.2020.1.545-550.

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The characteristic of the Crimean rivers for which the flood regime is characteristic is given. In 1974, the Balanovskoye reservoir was built on the Zuya river to meet the needs of the district's agriculture. The data on the calculation of the passage of floods through the hydroelectric Balanovsky reservoir, belonging to the II class of danger. Calibration of the maximum rate, according to the SP and 0.1% of the EAP. The assessment and 0.01% of the EAP of the flood pass by the existing structures of the hydroelectric facility was carried out. It is recommended to organize continuous observations of all parameters on the network of automatic stations, which will most fully characterize the entire situation in the basin and in its various sections, as well as provide information to a set of mathematical models for hydrodynamic modeling of surface runoff and channel runoff to intermediate branches, to assess the risks of dangerous hydrological phenomena in various parts of the basin with sufficient advance.
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Pedro, José, João Gomes und Luís Nunes. „CONSISTENT MODELING OF DC AND AC CHARACTERISTICS OF GaN/AlGaN MICROWAVE POWER HEMTS“. In Mathematical modeling in materials science of electronic component. LLC MAKS Press, 2020. http://dx.doi.org/10.29003/m1533.mmmsec-2020/106-109.

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This work discusses the necessary modelling efforts needed to build nonlinear equivalent-circuit models that can produce consistent directcurrent (dc) and alternate-current (ac) characteristics of non-quasi-static devices such as GaN/AlGaN HEMTs, showing electro-thermal and/or trapping behavior. With this goal in mind, a measurement methodology addressing both pulsed dc I/V characteristics and pulsed S-parameters is presented and exemplifying results are shown.
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Ashihara, Masa-aki, Atsuhide Kitagawa, Masa-aki Ishikawa, Akihiro Nakashinchi, Yuichi Murai und Fujio Yamamoto. „Particle Tracking Velocimetry Measurement of Bubble-Bubble Interaction“. In ASME/JSME 2003 4th Joint Fluids Summer Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/fedsm2003-45208.

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Bubble-bubble interaction is a quite fundamental issue to understand multiphase flow dynamics and to improve mathematical models of dispersed multiphase flow for higher volume fraction of dispersion. In this study, the bubble-bubble interaction is measured using Particle Tracking Velocimetry (PTV) in various environments. First, bubbles sliding on a vertical wall are measured using 2-D PTV. Second, the free rising bubbles in an unbounded space are measured applying 3-D PTV. Third, the simultaneous measurement for gas and liquid phases in the layer of wall-sliding bubbles is carried out. The measurement data have shown that the average bubble-bubble interaction patterns in the wall-sliding bubbles and in the free rising bubbles were attractive in the vertical direction and repulsive in the horizontal direction. The relation between the carrier phase flow structure and the bubbles’ motion is detected to explain the mechanism of the bubble-bubble interaction.
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