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Sample records for swat model applied

  1. Transferability of SWAT Models between SWAT2009 and SWAT2012.

    Science.gov (United States)

    Seo, Mijin; Yen, Haw; Kim, Min-Kyeong; Jeong, Jaehak

    2014-05-01

    In recent years, the Soil and Water Assessment Tool (SWAT) has experienced upgrades with enhanced functionalities and modeling capacities as it gets to the current version, SWAT2012. Changes in the SWAT code on a specific process may result in propagating influences in the output of other related processes. In this study, the characteristic significance of the enhancements in SWAT code was investigated using the two recent versions, SWAT2009 and SWAT2012. Using a global optimization technique, each model was calibrated for flow, sediment, and nutrient and then tested for transferability of parameters between the models. Results indicate that flow and water quality output were well calibrated with both models. However, the calibrated parameters determined by SWAT2009 and SWAT2012 were noticeably different, due mostly to the enhancements made in SWAT2012. Our results indicate that only the stream flow result was reliable when the models were upgraded or downgraded between the two versions after calibration. Sediment prediction was marginally reliable. SWAT parameters were nontransferrable if nutrient was the main output. The differences are due to various reasons, such as disparities in algorithms at the process level and propagation of the resulting uncertainty into higher-order processes. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  2. Historical Streamflow Series Analysis Applied to Furnas HPP Reservoir Watershed Using the SWAT Model

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    Viviane de Souza Dias

    2018-04-01

    Full Text Available Over the last few years, the operation of the Furnas Hydropower Plant (HPP reservoir, located in the Grande River Basin, has been threatened due to a significant reduction in inflow. In the region, hydrological modelling tools are being used and tested to support decision making and water sustainability. In this study, the streamflow was modelled in the area of direct influence of the Furnas HPP reservoir, and the Soil and Water Assessment Tool (SWAT model performance was verified for studies in the region. Analyses of sensitivity and uncertainty were undertaken using the Sequential Uncertainty Fitting algorithm (SUFI-2 with a Calibration Uncertainty Program (SWAT-CUP. The hydrological modelling, at a monthly scale, presented good results in the calibration (NS 0.86, with a slight reduction of the coefficient in the validation period (NS 0.64. The results suggested that this tool could be applied in future hydrological studies in the region of study. With the consideration that special attention should be given to the historical series used in the calibration and validation of the models. It is important to note that this region has high demands for water resources, primarily for agricultural use. Water demands must also be taken into account in future hydrological simulations. The validation of this methodology led to important contributions to the management of water resources in regions with tropical climates, whose climatological and geological reality resembles the one studied here.

  3. Evaluation of non-point source pollution reduction by applying best management practices using a SWAT model and QuickBird high resolution satellite imagery.

    Science.gov (United States)

    Lee, MiSeon; Park, GeunAe; Park, MinJi; Park, JongYoon; Lee, JiWan; Kim, SeongJoon

    2010-01-01

    This study evaluated the reduction effect of non-point source pollution by applying best management practices (BMPs) to a 1.21 km2 small agricultural watershed using a SWAT (Soil and Water Assessment Tool) model. Two meter QuickBird land use data were prepared for the watershed. The SWAT was calibrated and validated using daily streamflow and monthly water quality (total phosphorus (TP), total nitrogen (TN), and suspended solids (SS)) records from 1999 to 2000 and from 2001 to 2002. The average Nash and Sutcliffe model efficiency was 0.63 for the streamflow and the coefficients of determination were 0.88, 0.72, and 0.68 for SS, TN, and TP, respectively. Four BMP scenarios viz. the application of vegetation filter strip and riparian buffer system, the regulation of Universal Soil Loss Equation P factor, and the fertilizing control amount for crops were applied and analyzed.

  4. SWAT-based streamflow and embayment modeling of Karst-affected Chapel branch watershed, South Carolina

    Science.gov (United States)

    Devendra Amatya; M. Jha; A.E. Edwards; T.M. Williams; D.R. Hitchcock

    2011-01-01

    SWAT is a GIS-based basin-scale model widely used for the characterization of hydrology and water quality of large, complex watersheds; however, SWAT has not been fully tested in watersheds with karst geomorphology and downstream reservoir-like embayment. In this study, SWAT was applied to test its ability to predict monthly streamflow dynamics for a 1,555 ha karst...

  5. Validation of SWAT+ at field level and comparison with previous SWAT models in simulating hydrologic quantity

    Science.gov (United States)

    GAO, J.; White, M. J.; Bieger, K.; Yen, H.; Arnold, J. G.

    2017-12-01

    Over the past 20 years, the Soil and Water Assessment Tool (SWAT) has been adopted by many researches to assess water quantity and quality in watersheds around the world. As the demand increases in facilitating model support, maintenance, and future development, the SWAT source code and data have undergone major modifications over the past few years. To make the model more flexible in terms of interactions of spatial units and processes occurring in watersheds, a completely revised version of SWAT (SWAT+) was developed to improve SWAT's ability in water resource modelling and management. There are only several applications of SWAT+ in large watersheds, however, no study pays attention to validate the new model at field level and assess its performance. To test the basic hydrologic function of SWAT+, it was implemented in five field cases across five states in the U.S. and compared the SWAT+ created results with that from the previous models at the same fields. Additionally, an automatic calibration tool was used to test which model is easier to be calibrated well in a limited number of parameter adjustments. The goal of the study was to evaluate the performance of SWAT+ in simulating stream flow on field level at different geographical locations. The results demonstrate that SWAT+ demonstrated similar performance with previous SWAT model, but the flexibility offered by SWAT+ via the connection of different spatial objects can result in a more accurate simulation of hydrological processes in spatial, especially for watershed with artificial facilities. Autocalibration shows that SWAT+ is much easier to obtain a satisfied result compared with the previous SWAT. Although many capabilities have already been enhanced in SWAT+, there exist inaccuracies in simulation. This insufficiency will be improved with advancements in scientific knowledge on hydrologic process in specific watersheds. Currently, SWAT+ is prerelease, and any errors are being addressed.

  6. Applications of the SWAT Model Special Section: Overview and Insights.

    Science.gov (United States)

    Gassman, Philip W; Sadeghi, Ali M; Srinivasan, Raghavan

    2014-01-01

    The Soil and Water Assessment Tool (SWAT) model has emerged as one of the most widely used water quality watershed- and river basin-scale models worldwide, applied extensively for a broad range of hydrologic and/or environmental problems. The international use of SWAT can be attributed to its flexibility in addressing water resource problems, extensive networking via dozens of training workshops and the several international conferences that have been held during the past decade, comprehensive online documentation and supporting software, and an open source code that can be adapted by model users for specific application needs. The catalyst for this special collection of papers was the 2011 International SWAT Conference & Workshops held in Toledo, Spain, which featured over 160 scientific presentations representing SWAT applications in 37 countries. This special collection presents 22 specific SWAT-related studies, most of which were presented at the 2011 SWAT Conference; it represents SWAT applications on five different continents, with the majority of studies being conducted in Europe and North America. The papers cover a variety of topics, including hydrologic testing at a wide range of watershed scales, transport of pollutants in northern European lowland watersheds, data input and routing method effects on sediment transport, development and testing of potential new model algorithms, and description and testing of supporting software. In this introduction to the special section, we provide a synthesis of these studies within four main categories: (i) hydrologic foundations, (ii) sediment transport and routing analyses, (iii) nutrient and pesticide transport, and (iv) scenario analyses. We conclude with a brief summary of key SWAT research and development needs. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  7. Grid based calibration of SWAT hydrological models

    Directory of Open Access Journals (Sweden)

    D. Gorgan

    2012-07-01

    Full Text Available The calibration and execution of large hydrological models, such as SWAT (soil and water assessment tool, developed for large areas, high resolution, and huge input data, need not only quite a long execution time but also high computation resources. SWAT hydrological model supports studies and predictions of the impact of land management practices on water, sediment, and agricultural chemical yields in complex watersheds. The paper presents the gSWAT application as a web practical solution for environmental specialists to calibrate extensive hydrological models and to run scenarios, by hiding the complex control of processes and heterogeneous resources across the grid based high computation infrastructure. The paper highlights the basic functionalities of the gSWAT platform, and the features of the graphical user interface. The presentation is concerned with the development of working sessions, interactive control of calibration, direct and basic editing of parameters, process monitoring, and graphical and interactive visualization of the results. The experiments performed on different SWAT models and the obtained results argue the benefits brought by the grid parallel and distributed environment as a solution for the processing platform. All the instances of SWAT models used in the reported experiments have been developed through the enviroGRIDS project, targeting the Black Sea catchment area.

  8. ESTIMATIVA DO BALANÇO SEDIMENTAR DA BACIA DO RIO TIJUCAS (SC-BRASIL A PARTIR DA APLICAÇÃO DO MODELO HIDROLÓGICO SWAT / ESTIMATE OF SEDIMENT BUDGET OF THE TIJUCAS RIVER BASIN APPLYING SWAT HYDROLOGIC MODEL

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    Jean Berná Paim

    2009-12-01

    Full Text Available Adopt a basin as a hydrological unit to understand the physical processes related to the water and sediment production is important because its characteristics (area, shape and topography can determine its use in a sustainable manner. This study is aim in the test of the applicability of hydrologic model SWAT (Soil and Water Assessment Tool in the Tijucas River Basin to quantify the water and sediment production along it sub-basins. Together, geoprocessing techniques were applied with the creation of a database of geographical information to describe the region. On this database is included the daily precipitation an temperature data of the gauges distributed on the watershed, soil data, a land use map and the digital elevation model (DEM to create the Hydrologic Response Units (HRU’s. A time series with flow values and sediment concentration measured are very important to calibrate and validate the model output parameters. After the calibration of the initial results, the Flow Gauge number 102 presented a Nash and Sutcliffe Coefficient - COE = 0.6 indicating a good adjust of the model. The results were used to create a sediment production map for Tijucas River Basin, when the 10 years average ranged between 0.5 ton/ha and 9.0 ton/ha in some sub-basins.

  9. A fully integrated SWAT-MODFLOW hydrologic model

    Science.gov (United States)

    The Soil and Water Assessment Tool (SWAT) and MODFLOW models are being used worldwide for managing surface and groundwater water resources. The SWAT models hydrological processes occurring at the surface including shallow aquifers, while MODFLOW simulate groundwater processes. However, neither SWAT ...

  10. A GUIDED SWAT MODEL APPLICATION ON SEDIMENT YIELD MODELING IN PANGANI RIVER BASIN: LESSONS LEARNT

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    Preksedis Marco Ndomba

    2008-12-01

    Full Text Available The overall objective of this paper is to report on the lessons learnt from applying Soil and Water Assessment Tool (SWAT in a well guided sediment yield modelling study. The study area is the upstream of Pangani River Basin (PRB, the Nyumba Ya Mungu (NYM reservoir catchment, located in the North Eastern part of Tanzania. It should be noted that, previous modeling exercises in the region applied SWAT with preassumption that inter-rill or sheet erosion was the dominant erosion type. In contrast, in this study SWAT model application was guided by results of analysis of high temporal resolution of sediment flow data and hydro-meteorological data. The runoff component of the SWAT model was calibrated from six-years (i.e. 1977–1982 of historical daily streamflow data. The sediment component of the model was calibrated using one-year (1977–1988 daily sediment loads estimated from one hydrological year sampling programme (between March and November, 2005 rating curve. A long-term period over 37 years (i.e. 1969–2005 simulation results of the SWAT model was validated to downstream NYM reservoir sediment accumulation information. The SWAT model captured 56 percent of the variance (CE and underestimated the observed daily sediment loads by 0.9 percent according to Total Mass Control (TMC performance indices during a normal wet hydrological year, i.e., between November 1, 1977 and October 31, 1978, as the calibration period. SWAT model predicted satisfactorily the long-term sediment catchment yield with a relative error of 2.6 percent. Also, the model has identified erosion sources spatially and has replicated some erosion processes as determined in other studies and field observations in the PRB. This result suggests that for catchments where sheet erosion is dominant SWAT model may substitute the sediment-rating curve. However, the SWAT model could not capture the dynamics of sediment load delivery in some seasons to the catchment outlet.

  11. A GUIDED SWAT MODEL APPLICATION ON SEDIMENT YIELD MODELING IN PANGANI RIVER BASIN: LESSONS LEARNT

    Directory of Open Access Journals (Sweden)

    Preksedis M. Ndomba

    2008-01-01

    Full Text Available The overall objective of this paper is to report on the lessons learnt from applying Soil and Water Assessment Tool (SWAT in a well guided sediment yield modelling study. The study area is the upstream of Pangani River Basin (PRB, the Nyumba Ya Mungu (NYM reservoir catchment, located in the North Eastern part of Tanzania. It should be noted that, previous modeling exercises in the region applied SWAT with preassumption that inter-rill or sheet erosion was the dominant erosion type. In contrast, in this study SWAT model application was guided by results of analysis of high temporal resolution of sediment flow data and hydro-meteorological data. The runoff component of the SWAT model was calibrated from six-years (i.e. 1977¿1982 of historical daily streamflow data. The sediment component of the model was calibrated using one-year (1977-1988 daily sediment loads estimated from one hydrological year sampling programme (between March and November, 2005 rating curve. A long-term period over 37 years (i.e. 1969-2005 simulation results of the SWAT model was validated to downstream NYM reservoir sediment accumulation information. The SWAT model captured 56 percent of the variance (CE and underestimated the observed daily sediment loads by 0.9 percent according to Total Mass Control (TMC performance indices during a normal wet hydrological year, i.e., between November 1, 1977 and October 31, 1978, as the calibration period. SWAT model predicted satisfactorily the long-term sediment catchment yield with a relative error of 2.6 percent. Also, the model has identified erosion sources spatially and has replicated some erosion processes as determined in other studies and field observations in the PRB. This result suggests that for catchments where sheet erosion is dominant SWAT model may substitute the sediment-rating curve. However, the SWAT model could not capture the dynamics of sediment load delivery in some seasons to the catchment outlet.

  12. SWAT Model Configuration, Calibration and Validation for Lake Champlain Basin

    Science.gov (United States)

    The Soil and Water Assessment Tool (SWAT) model was used to develop phosphorus loading estimates for sources in the Lake Champlain Basin. This document describes the model setup and parameterization, and presents calibration results.

  13. Pathogen Transport and Fate Modeling in the Upper Salem River Watershed Using SWAT Model

    Science.gov (United States)

    SWAT (Soil and Water Assessment Tool) is a dynamic watershed model that is applied to simulate the impact of land management practices on water quality over a continuous period. The Upper Salem River, located in Salem County New Jersey, is listed by the New Jersey Department of ...

  14. Hydrosedimentological modeling of watershed in southeast Brazil, using SWAT

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    Maria Lúcia Calijuri

    2010-08-01

    Full Text Available The quantitative evaluation of soil loss due to erosion, of water loss and of load sediments that reach water bodies is fundamental to the environmental planning of a watershed, contributing to the process of decision for best options for soil tillage and water quality maintenance. Estimates of these data have been accomplished throughout the world using empiric or conceptual models. Besides being economically viable in scenarios development, environmental models may contribute to the location of critical areas, leading to emergency contention operations caused by erosive processes. Among these models, we highlight the SWAT (Soil and Water Assessment Tool which was applied in São Bartolomeu watershed, located in the Zona da Mata, Minas Gerais state, southeastern Brazil, to identify areas of greater sensitivity to erosion considering the soil type and land use. To validate the model, 10 experimental plots were installed in the dominant crops of the watershed between 2006 and 2008, for monitoring the runoff and soil losses under natural rainfall. Field results and simulations showed the SWAT efficiency for sediment yield and soil losses estimations, as they are influenced by factors such as soil moisture, rainfall intensity, soil type and land use (dominated by Oxisols, Ultisols, Inceptisols and Entisols. These losses can be reduced significantly by improving crops management of. A simulation scenario replacing pastures cover by Eucalyptus was introduced, which significantly reduced soil loss in many parts of the watershed.

  15. Improving the spatial representation of basin hydrology and flow processes in the SWAT model

    OpenAIRE

    Rathjens, Hendrik

    2014-01-01

    This dissertation aims at improving the spatial representation of basin hydrology and flow processes in the SWAT model. Die vorliegende Dissertation stellt die methodischen Grundlage zur räumlich differenzierten Modellierung mit dem Modell SWAT dar.

  16. Analisis Laju Sedimen DAS Serayu Hulu dengan Menggunakan Model SWAT

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    Nugroho Christanto

    2018-03-01

    Full Text Available Wilayah DAS Serayu Hulu merupakan DAS prioritas yang memerlukan langkah pengelolaan yang komprehensif. Aplikasi model Soil and Water Assessment Tool (SWAT dapat digunakan sebagai media untuk  perencanaan konservasi ataupun evaluasi respon DAS (debit aliran permukaan, sedimen dan pencemaran sungai. Tujuan utama dari penelitian ini adalah menjalankan model SWAT di DAS Serayu Hulu untuk mengetahui laju sedimen di wilayah ini. Pemodelan SWAT membutuhkan sejumlah input parameter berupa relief, tanah, tutupan lahan dan pengelolaan lahan. Pedogeomorfologi digunakan sebagai batas satuan tanah karena tidak tersedianya peta tanah di wilayah penelitian. Hasil Penerapan model SWAT di DAS Serayu Hulu menghasilkan nilai yang cukup memuaskan, hal ini ditunjukkan nilai R2 mencapai 0,94. Hasil pemodelan SWAT dengan menggunakan data selama 10 tahun (2004-2013 menunjukkan bahwa DAS Serayu Hulu memiliki rerata hasil sedimen sebesar 1.926.900 ton/tahun. Sub DAS 8,9 11, 17, 18, dan 19 merupakan penghasil sedimen tertinggi di DAS Serayu Hulu dengan hasil sedimen 43.931– 121.434 ton/ha/tahun.

  17. Pesticide modelling for a small catchment using SWAT-2000.

    Science.gov (United States)

    Kannan, Narayanan; White, Sue M; Worrall, Fred; Whelan, Mick J

    2006-01-01

    Pesticides in stream flow from the 142 ha Colworth catchment in Bedfordshire, UK were monitored from October 1999 to December 2000. About 47% of the catchment is tile-drained and different pesticides and cropping patterns have recently been evaluated in terms of their effect on nutrient and pesticide losses to the stream. The data from Colworth were used to test soil and water assessment tool (SWAT) 2000 predictions of pesticide concentrations at the catchment outlet. A sound model set-up to carry out pesticide modelling was created by means of hydrological modelling with proper simulation of crop growth and evapotranspiration. The pesticides terbuthylazine, terbutryn, cyanazine and bentazone were modelled. There was close agreement between SWAT-predicted pesticide concentration values and observations. Scenario trials were conducted to explore management options for reducing pesticide loads arriving at the catchment outlet. The results obtained indicate that SWAT can be used as a tool to understand pesticide behavior at the catchment scale.

  18. Flow forecast by SWAT model and ANN in Pracana basin, Portugal

    NARCIS (Netherlands)

    Demirel, M.C.; Venancio, Anabela; Kahya, Ercan

    2009-01-01

    This study provides a unique opportunity to analyze the issue of flow forecast based on the soil and water assessment tool (SWAT) and artificial neural network (ANN) models. In last two decades, the ANNs have been extensively applied to various water resources system problems. In this study, the

  19. Introducing a new open source GIS user interface for the SWAT model

    Science.gov (United States)

    The Soil and Water Assessment Tool (SWAT) model is a robust watershed modelling tool. It typically uses the ArcSWAT interface to create its inputs. ArcSWAT is public domain software which works in the licensed ArcGIS environment. The aim of this paper was to develop an open source user interface ...

  20. Evaluation of alternative surface runoff accounting procedures using the SWAT model

    Science.gov (United States)

    For surface runoff estimation in the Soil and Water Assessment Tool (SWAT) model, the curve number (CN) procedure is commonly adopted to calculate surface runoff by utilizing antecedent soil moisture condition (SCSI) in field. In the recent version of SWAT (SWAT2005), an alternative approach is ava...

  1. Modeling riverine nitrate export from an East-Central Illinois watershed using SWAT.

    Science.gov (United States)

    Hu, X; McIsaac, G F; David, M B; Louwers, C A L

    2007-01-01

    Reliable water quality models are needed to forecast the water quality consequences of different agricultural nutrient management scenarios. In this study, the Soil and Water Assessment Tool (SWAT), version 2000, was applied to simulate streamflow, riverine nitrate (NO(3)) export, crop yield, and watershed nitrogen (N) budgets in the upper Embarras River (UER) watershed in east-central Illinois, which has extensive maize-soybean cultivation, large N fertilizer input, and extensive tile drainage. During the calibration (1994-2002) and validation (1985-1993) periods, SWAT simulated monthly and annual stream flows with Nash-Sutcliffe coefficients (E) ranging from 0.67 to 0.94 and R(2) from 0.75 to 0.95. For monthly and annual NO(3) loads, E ranged from -0.16 to 0.45 and R(2) from 0.36 to 0.74. Annual maize and soybean yields were simulated with relative errors ranging from -10 to 6%. The model was then used to predict the changes in NO(3) output with N fertilizer application rates 10 to 50% lower than original application rates in UER. The calibrated SWAT predicted a 10 to 43% decrease in NO(3) export from UER and a 6 to 38% reduction in maize yield in response to the reduction in N fertilizer. The SWAT model markedly overestimated NO(3) export during major wet periods. Moreover, SWAT estimated soybean N fixation rates considerably greater than literature values, and some simulated changes in the N cycle in response to fertilizer reduction seemed to be unrealistic. Improving these aspects of SWAT could lead to more reliable predictions in the water quality outcomes of nutrient management practices in tile-drained watersheds.

  2. Validating soil phosphorus routines in the SWAT model

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    Phosphorus transfer from agricultural soils to surface waters is an important environmental issue. Commonly used models like SWAT have not always been updated to reflect improved understanding of soil P transformations and transfer to runoff. Our objective was to validate the ability of the P routin...

  3. PEMODELAN DAERAH TANGKAPAN AIR WADUK KELILING DENGAN MODEL SWAT (Keliling Reservoir Catchment Area Modeling Using SWAT Model

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    Teuku Ferijal

    2015-05-01

    Full Text Available This study aimed to model watershed area of Keliling Reservoir using SWAT model. The reservoir is located in Aceh Besar District, Province of Aceh. The model was setup using 90m x 90m digital elevation model, land use data extracted from remote sensing data and soil characteristic obtained from laboratory analysis on soil samples. Model was calibrated using observed daily reservoir volume and the model performance was analyzed using RMSE-observations standard deviation ratio (RSR, Nash-Sutcliffe efficiency (NSE and percent bias (PBIAS. The model delineated the study area into 3,448 Ha having 13 subwatersheds and 76 land units (HRUs. The watershed is mostly covered by forest (53% and grassland (31%. The analysis revealed the 10 most sensitive parameters i.e. GW_DELAY, CN2, REVAPMN, ALPHA_BF, SOL_AWC, GW_REVAP, GWQMN, CH_K2 and ESCO. Model performances were categorized into very good for monthly reservoir volume with ENS 0.95, RSR 0.23, and PBIAS 2.97. The model performance decreased when it used to analyze daily reservoir inflow with ENS 0.55, RSR 0.67, and PBIAS 3.46. Keywords: Keliling Reservoir, SWAT, Watershed   ABSTRAK Penelitian ini bertujuan untuk untuk memodelkan daerah tangkapan air Waduk Keliling dengan menggunakan Model SWAT. Waduk Keliling terletak di Kabupaten Aceh Besar, Propinsi Aceh. Dalam penelitian ini Model SWAT dikembangkan berdasarkan data digital elevasi model resolusi 90 m x90 m, tata guna lahan yang diperoleh dari intepretasi citra satelit dan data soil dari hasil analisa sampel tanah yang diperoleh di daerah penelitian. Model dikalibrasi dengan data volume waduk dan kinerja model dianalisa menggunakan parameter rasio akar rata-rata kuadrat error dan standard deviasi observasi (RSR, efesiensi Nash-Sutcliffe (NSE dan persentase bias (PBIAS. Hasil deleniasi untuk daerah penelitian menghasilkan suatu DAS dengan luas 3,448 Ha dan memiliki 13 Sub DAS yang dikelompokkan menjadi 76 unit lahan. Sebagian besar wilayah study

  4. Advancing representation of hydrologic processes in the Soil and Water Assessment Tool (SWAT) through integration of the TOPographic MODEL (TOPMODEL) features

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    Chen, J.; Wu, Y.

    2012-01-01

    This paper presents a study of the integration of the Soil and Water Assessment Tool (SWAT) model and the TOPographic MODEL (TOPMODEL) features for enhancing the physical representation of hydrologic processes. In SWAT, four hydrologic processes, which are surface runoff, baseflow, groundwater re-evaporation and deep aquifer percolation, are modeled by using a group of empirical equations. The empirical equations usually constrain the simulation capability of relevant processes. To replace these equations and to model the influences of topography and water table variation on streamflow generation, the TOPMODEL features are integrated into SWAT, and a new model, the so-called SWAT-TOP, is developed. In the new model, the process of deep aquifer percolation is removed, the concept of groundwater re-evaporation is refined, and the processes of surface runoff and baseflow are remodeled. Consequently, three parameters in SWAT are discarded, and two new parameters to reflect the TOPMODEL features are introduced. SWAT-TOP and SWAT are applied to the East River basin in South China, and the results reveal that, compared with SWAT, the new model can provide a more reasonable simulation of the hydrologic processes of surface runoff, groundwater re-evaporation, and baseflow. This study evidences that an established hydrologic model can be further improved by integrating the features of another model, which is a possible way to enhance our understanding of the workings of catchments.

  5. Improvement and application of the PCPF-1@SWAT2012 model for predicting pesticide transport: A case study of the Sakura River watershed.

    Science.gov (United States)

    Tu, Le Hoang; Boulange, Julien; Iwafune, Takashi; Yadav, Ishwar Chandra; Watanabe, Hirozumi

    2018-04-15

    The PCPF-1@SWAT model was previously developed to simulate the fate and transport of rice pesticide in watersheds. However, the current model is deficient in characterize the rice paddy area and is incompatible with the ArcSWAT2012 program. In this study, we modified original PCPF1@SWAT model to develop new PCPF1@SWAT2012 model to address the deficiency of rice paddy area and utilizing the ArcSWAT2012 program. Next, the new model was applied in Sakura River watershed, Ibaraki, Japan in order to simulate the transport of four herbicides including mefenacet, pretilachlor, bensulfuron-methyl and imazosulfuron. The result showed that the simulated water flow rate by the PCPF1@SWAT2012 was well predicted with the observed data. The calculated NSE (0.73) and PBIAS (-20.38), suggested the satisfactory performance of the model. Besides, the concentrations of herbicides simulated by the PCPF-1@SWAT2012 model were in good agreement with the observed data. Statistical indices, NSE and RMSE estimated for mefenacet (0.69 and 0.18), pretilachlor (0.86 and 0.18), bensulfuronmethyl (0.46 and 0.21) and imazosulfuron (0.64 and 0.28) indicated satisfactory predictions, respectively. The PCPF-1@SWAT2012 model is capable of well simulating the water flow rate and transport of herbicides in given watershed, comprising different land use types, including rice paddy area. This article is protected by copyright. All rights reserved.

  6. Impacts of manure application on SWAT model outputs in the Xiangxi River watershed

    Science.gov (United States)

    Liu, Ruimin; Wang, Qingrui; Xu, Fei; Men, Cong; Guo, Lijia

    2017-12-01

    SWAT (Soil and Water Assessment Tool) model has been widely used to simulate agricultural non-point source (ANPS) pollution; however, the impacts of livestock manure application on SWAT model outputs have not been well studied. The objective of this study was to investigate the environmental effects of livestock manure application based on the SWAT model in the Xiangxi River watershed, which is one of the largest tributaries of the Three Gorges Reservoir in China. Three newly-built manure databases (NB) were created and applied to different subbasins based on the actual livestock manure discharging amount. The calibration and validation values of SWAT model outputs obtained from the NB manure application and the original mixed (OM) manure were compared. The study results are as follows: (1) The livestock industry of Xingshan County developed quickly between 2005 and 2015. The downstream of the Xiangxi River (Huangliang, Shuiyuesi and Xiakou) had the largest livestock amount, and largely accounted for manure, total nitrogen (TN) and total phosphorus (TP) production (>50%). (2) The NB manure application resulted in less phosphorus pollution (1686.35 kg for ORGP and 31.70 kg for MINP) than the OM manure application. Compared with the upstream, the downstream was influenced more by the manure application. (3) The SWAT results obtained from the NB manure had a better calibration and validation values than those from the OM manure. For ORGP, R2 and NSE values were 0.77 and 0.65 for the NB manure calibration; and the same values for the OM manure were 0.72 and 0.61, respectively. For MINP, R2 values were 0.65 and 0.62 for the NB manure and the OM manure, and the NSE values were 0.60 and 0.58, respectively. The results indicated that the built-in fertilizer database in SWAT has its limitation because it is set up for the simulation in the USA. Thus, when livestock manure is considered in a SWAT simulation, a newly built fertilizer database needs to be set up to represent

  7. Prediction of phosphorus loads in an artificially drained lowland catchment using a modified SWAT model

    Science.gov (United States)

    Bauwe, Andreas; Eckhardt, Kai-Uwe; Lennartz, Bernd

    2017-04-01

    Eutrophication is still one of the main environmental problems in the Baltic Sea. Currently, agricultural diffuse sources constitute the major portion of phosphorus (P) fluxes to the Baltic Sea and have to be reduced to achieve the HELCOM targets and improve the ecological status. Eco-hydrological models are suitable tools to identify sources of nutrients and possible measures aiming at reducing nutrient loads into surface waters. In this study, the Soil and Water Assessment Tool (SWAT) was applied to the Warnow river basin (3300 km2), the second largest watershed in Germany discharging into the Baltic Sea. The Warnow river basin is located in northeastern Germany and characterized by lowlands with a high proportion of artificially drained areas. The aim of this study were (i) to estimate P loadings for individual flow fractions (point sources, surface runoff, tile flow, groundwater flow), spatially distributed on sub-basin scale. Since the official version of SWAT does not allow for the modeling of P in tile drains, we tested (ii) two different approaches of simulating P in tile drains by changing the SWAT source code. The SWAT source code was modified so that (i) the soluble P concentration of the groundwater was transferred to the tile water and (ii) the soluble P in the soil was transferred to the tiles. The SWAT model was first calibrated (2002-2011) and validated (1992-2001) for stream flow at 7 headwater catchments at a daily time scale. Based on this, the stream flow at the outlet of the Warnow river basin was simulated. Performance statistics indicated at least satisfactory model results for each sub-basin. Breaking down the discharge into flow constituents, it becomes visible that stream flow is mainly governed by groundwater and tile flow. Due to the topographic situation with gentle slopes, surface runoff played only a minor role. Results further indicate that the prediction of soluble P loads was improved by the modified SWAT versions. Major sources of

  8. Slope effects on SWAT modeling in a mountainous basin

    OpenAIRE

    Yacoub López, Cristina; Pérez Foguet, Agustí

    2013-01-01

    The soil and water assessment tool (SWAT) is a distributed basin model that includes the option of defining spatial discretization in terms of terrain slope. Influence of terrain slope in runoff results from mountain basins is a determining factor in its simulation results; however, its use as a criterion for basin discretization and for the parameter calibration has not yet been analyzed. In this study, this influence is analyzed for calibrations using two different cases. Ten discretization...

  9. A simple rule based model for scheduling farm management operations in SWAT

    Science.gov (United States)

    Schürz, Christoph; Mehdi, Bano; Schulz, Karsten

    2016-04-01

    For many interdisciplinary questions at the watershed scale, the Soil and Water Assessment Tool (SWAT; Arnold et al., 1998) has become an accepted and widely used tool. Despite its flexibility, the model is highly demanding when it comes to input data. At SWAT's core the water balance and the modeled nutrient cycles are plant growth driven (implemented with the EPIC crop growth model). Therefore, land use and crop data with high spatial and thematic resolution, as well as detailed information on cultivation and farm management practices are required. For many applications of the model however, these data are unavailable. In order to meet these requirements, SWAT offers the option to trigger scheduled farm management operations by applying the Potential Heat Unit (PHU) concept. The PHU concept solely takes into account the accumulation of daily mean temperature for management scheduling. Hence, it contradicts several farming strategies that take place in reality; such as: i) Planting and harvesting dates are set much too early or too late, as the PHU concept is strongly sensitivity to inter-annual temperature fluctuations; ii) The timing of fertilizer application, in SWAT this often occurs simultaneously on the same date in in each field; iii) and can also coincide with precipitation events. Particularly, the latter two can lead to strong peaks in modeled nutrient loads. To cope with these shortcomings we propose a simple rule based model (RBM) to schedule management operations according to realistic farmer management practices in SWAT. The RBM involves simple strategies requiring only data that are input into the SWAT model initially, such as temperature and precipitation data. The user provides boundaries of time periods for operation schedules to take place for all crops in the model. These data are readily available from the literature or from crop variety trials. The RBM applies the dates by complying with the following rules: i) Operations scheduled in the

  10. Multivariate Bias Correction Procedures for Improving Water Quality Predictions from the SWAT Model

    Science.gov (United States)

    Arumugam, S.; Libera, D.

    2017-12-01

    Water quality observations are usually not available on a continuous basis for longer than 1-2 years at a time over a decadal period given the labor requirements making calibrating and validating mechanistic models difficult. Further, any physical model predictions inherently have bias (i.e., under/over estimation) and require post-simulation techniques to preserve the long-term mean monthly attributes. This study suggests a multivariate bias-correction technique and compares to a common technique in improving the performance of the SWAT model in predicting daily streamflow and TN loads across the southeast based on split-sample validation. The approach is a dimension reduction technique, canonical correlation analysis (CCA) that regresses the observed multivariate attributes with the SWAT model simulated values. The common approach is a regression based technique that uses an ordinary least squares regression to adjust model values. The observed cross-correlation between loadings and streamflow is better preserved when using canonical correlation while simultaneously reducing individual biases. Additionally, canonical correlation analysis does a better job in preserving the observed joint likelihood of observed streamflow and loadings. These procedures were applied to 3 watersheds chosen from the Water Quality Network in the Southeast Region; specifically, watersheds with sufficiently large drainage areas and number of observed data points. The performance of these two approaches are compared for the observed period and over a multi-decadal period using loading estimates from the USGS LOADEST model. Lastly, the CCA technique is applied in a forecasting sense by using 1-month ahead forecasts of P & T from ECHAM4.5 as forcings in the SWAT model. Skill in using the SWAT model for forecasting loadings and streamflow at the monthly and seasonal timescale is also discussed.

  11. Application of the SWAT model to the Xiangjiang river watershed in subtropical central China.

    Science.gov (United States)

    Luo, Qiao; Li, Yong; Wang, Kelin; Wu, Jinshui

    2013-01-01

    The Soil and Water Assessment Tool (SWAT) model was applied to simulate the water balance in the Xiangjiang river watershed for current and planning scenarios of land uses. The model was first calibrated for the period from 1998 to 2002 and then validated for the period from 2003 to 2007 using the observed stream flow data from four monitoring gages within the watershed. The determination coefficient of linear regression of the observed and simulated monthly stream flows (R(2)) and their Nash-Sutcliffe Index (NSI) was used to evaluate model performance. All values of R(2) and NSI were above 0.8 and ranged from 0.82 to 0.92, which indicates that the SWAT model was capable of simulating the stream flow in the Xiangjiang river watershed. The calibrated and validated SWAT model was then applied to study the hydrological response of three land use change scenarios. Runoff was reduced by increasing the areas of forest and grassland while simultaneously decreasing the areas of agricultural and urban land. In the recent and future land use planning for the Xiangjiang river watershed, the hydrological effect should be considered in regional water management and erosion control.

  12. SWAT Modeling for Depression-Dominated Areas: How Do Depressions Manipulate Hydrologic Modeling?

    Directory of Open Access Journals (Sweden)

    Mohsen Tahmasebi Nasab

    2017-01-01

    Full Text Available Modeling hydrologic processes for depression-dominated areas such as the North American Prairie Pothole Region is complex and reliant on a clear understanding of dynamic filling-spilling-merging-splitting processes of numerous depressions over the surface. Puddles are spatially distributed over a watershed and their sizes, storages, and interactions vary over time. However, most hydrologic models fail to account for these dynamic processes. Like other traditional methods, depressions are filled as a required preprocessing step in the Soil and Water Assessment Tool (SWAT. The objective of this study was to facilitate hydrologic modeling for depression-dominated areas by coupling SWAT with a Puddle Delineation (PD algorithm. In the coupled PD-SWAT model, the PD algorithm was utilized to quantify topographic details, including the characteristics, distribution, and hierarchical relationships of depressions, which were incorporated into SWAT at the hydrologic response unit (HRU scale. The new PD-SWAT model was tested for a large watershed in North Dakota under real precipitation events. In addition, hydrologic modeling of a small watershed was conducted under two extreme high and low synthetic precipitation conditions. In particular, the PD-SWAT was compared against the regular SWAT based on depressionless DEMs. The impact of depressions on the hydrologic modeling of the large and small watersheds was evaluated. The simulation results for the large watershed indicated that SWAT systematically overestimated the outlet discharge, which can be attributed to the failure to account for the hydrologic effects of depressions. It was found from the PD-SWAT modeling results that at the HRU scale surface runoff initiation was significantly delayed due to the threshold control of depressions. Under the high precipitation scenario, depressions increased the surface runoff peak. However, the low precipitation scenario could not fully fill depressions to reach

  13. Evaluation of best management practices under intensive irrigation using SWAT model

    OpenAIRE

    Dechmi, Farida; Skhiri, Ahmed

    2013-01-01

    Land management practices such as conservation tillage and optimum irrigation are routinely used to reduce non-point source pollution and improve water quality. The calibrated and validated SWAT-IRRIG model is the first modified SWAT version that reproduces well the irrigation return flows (IRF) when the irrigation source is outside of the watershed. The application of this SWAT version in intensive irrigated systems permits to better evaluate the best management practices (BMPs) in such syst...

  14. Management-oriented sensitivity analysis for pesticide transport in watershed-scale water quality modeling using SWAT

    International Nuclear Information System (INIS)

    Luo Yuzhou; Zhang Minghua

    2009-01-01

    The Soil and Water Assessment Tool (SWAT) was calibrated for hydrology conditions in an agricultural watershed of Orestimba Creek, California, and applied to simulate fate and transport of two organophosphate pesticides chlorpyrifos and diazinon. The model showed capability in evaluating pesticide fate and transport processes in agricultural fields and instream network. Management-oriented sensitivity analysis was conducted by applied stochastic SWAT simulations for pesticide distribution. Results of sensitivity analysis identified the governing processes in pesticide outputs as surface runoff, soil erosion, and sedimentation in the study area. By incorporating sensitive parameters in pesticide transport simulation, effects of structural best management practices (BMPs) in improving surface water quality were demonstrated by SWAT modeling. This study also recommends conservation practices designed to reduce field yield and in-stream transport capacity of sediment, such as filter strip, grassed waterway, crop residue management, and tailwater pond to be implemented in the Orestimba Creek watershed. - Selected structural BMPs are recommended for reducing loads of OP pesticides.

  15. Management-oriented sensitivity analysis for pesticide transport in watershed-scale water quality modeling using SWAT

    Energy Technology Data Exchange (ETDEWEB)

    Luo Yuzhou [University of California, Davis, CA 95616 (United States); Wenzhou Medical College, Wenzhou 325035 (China); Zhang Minghua, E-mail: mhzhang@ucdavis.ed [University of California, Davis, CA 95616 (United States); Wenzhou Medical College, Wenzhou 325035 (China)

    2009-12-15

    The Soil and Water Assessment Tool (SWAT) was calibrated for hydrology conditions in an agricultural watershed of Orestimba Creek, California, and applied to simulate fate and transport of two organophosphate pesticides chlorpyrifos and diazinon. The model showed capability in evaluating pesticide fate and transport processes in agricultural fields and instream network. Management-oriented sensitivity analysis was conducted by applied stochastic SWAT simulations for pesticide distribution. Results of sensitivity analysis identified the governing processes in pesticide outputs as surface runoff, soil erosion, and sedimentation in the study area. By incorporating sensitive parameters in pesticide transport simulation, effects of structural best management practices (BMPs) in improving surface water quality were demonstrated by SWAT modeling. This study also recommends conservation practices designed to reduce field yield and in-stream transport capacity of sediment, such as filter strip, grassed waterway, crop residue management, and tailwater pond to be implemented in the Orestimba Creek watershed. - Selected structural BMPs are recommended for reducing loads of OP pesticides.

  16. Management-oriented sensitivity analysis for pesticide transport in watershed-scale water quality modeling using SWAT.

    Science.gov (United States)

    Luo, Yuzhou; Zhang, Minghua

    2009-12-01

    The Soil and Water Assessment Tool (SWAT) was calibrated for hydrology conditions in an agricultural watershed of Orestimba Creek, California, and applied to simulate fate and transport of two organophosphate pesticides chlorpyrifos and diazinon. The model showed capability in evaluating pesticide fate and transport processes in agricultural fields and instream network. Management-oriented sensitivity analysis was conducted by applied stochastic SWAT simulations for pesticide distribution. Results of sensitivity analysis identified the governing processes in pesticide outputs as surface runoff, soil erosion, and sedimentation in the study area. By incorporating sensitive parameters in pesticide transport simulation, effects of structural best management practices (BMPs) in improving surface water quality were demonstrated by SWAT modeling. This study also recommends conservation practices designed to reduce field yield and in-stream transport capacity of sediment, such as filter strip, grassed waterway, crop residue management, and tailwater pond to be implemented in the Orestimba Creek watershed.

  17. Using StorAge Selection Functions to Improve Simulation of Groundwater Nitrate Lag Times in the SWAT Modeling Framework.

    Science.gov (United States)

    Wilusz, D. C.; Fuka, D.; Cho, C.; Ball, W. P.; Easton, Z. M.; Harman, C. J.

    2017-12-01

    Intensive agriculture and atmospheric deposition have dramatically increased the input of reactive nitrogen into many watersheds worldwide. Reactive nitrogen can leach as nitrate into groundwater, which is stored and eventually released over years to decades into surface waters, potentially degrading water quality. To simulate the fate and transport of groundwater nitrate, many researchers and practitioners use the Soil and Water Assessment Tool (SWAT) or an enhanced version of SWAT that accounts for topographically-driven variable source areas (TopoSWAT). Both SWAT and TopoSWAT effectively assume that nitrate in the groundwater reservoir is well-mixed, which is known to be a poor assumption at many sites. In this study, we describe modifications to TopoSWAT that (1) relax the assumption of groundwater well-mixedness, (2) more flexibly parameterize groundwater transport as a time-varying distribution of travel times using the recently developed theory of rank StorAge Selection (rSAS) functions, and (3) allow for groundwater age to be represented by position on the hillslope or hydrological distance from the stream. The approach conceptualizes the groundwater aquifer as a population of water parcels entering as recharge with a particular nitrate concentration, aging as they move through storage, and eventually exiting as baseflow. The rSAS function selects the distribution of parcel ages that exit as baseflow based on a parameterized probability distribution; this distribution can be adjusted to preferentially select different distributions of young and old parcels in storage so as to reproduce (in principle) any form of transport. The modified TopoSWAT model (TopoSWAT+rSAS) is tested at a small agricultural catchment in the Eastern Shore, MD with an extensive hydrologic and hydrochemical data record for calibration and evaluation. The results examine (1) the sensitivity of TopoSWAT+rSAS modeling of nitrate transport to assumptions about the distribution of travel

  18. A multi-objective approach to improve SWAT model calibration in alpine catchments

    Science.gov (United States)

    Tuo, Ye; Marcolini, Giorgia; Disse, Markus; Chiogna, Gabriele

    2018-04-01

    Multi-objective hydrological model calibration can represent a valuable solution to reduce model equifinality and parameter uncertainty. The Soil and Water Assessment Tool (SWAT) model is widely applied to investigate water quality and water management issues in alpine catchments. However, the model calibration is generally based on discharge records only, and most of the previous studies have defined a unique set of snow parameters for an entire basin. Only a few studies have considered snow observations to validate model results or have taken into account the possible variability of snow parameters for different subbasins. This work presents and compares three possible calibration approaches. The first two procedures are single-objective calibration procedures, for which all parameters of the SWAT model were calibrated according to river discharge alone. Procedures I and II differ from each other by the assumption used to define snow parameters: The first approach assigned a unique set of snow parameters to the entire basin, whereas the second approach assigned different subbasin-specific sets of snow parameters to each subbasin. The third procedure is a multi-objective calibration, in which we considered snow water equivalent (SWE) information at two different spatial scales (i.e. subbasin and elevation band), in addition to discharge measurements. We tested these approaches in the Upper Adige river basin where a dense network of snow depth measurement stations is available. Only the set of parameters obtained with this multi-objective procedure provided an acceptable prediction of both river discharge and SWE. These findings offer the large community of SWAT users a strategy to improve SWAT modeling in alpine catchments.

  19. Regionalization of SWAT Model Parameters for Use in Ungauged Watersheds

    Directory of Open Access Journals (Sweden)

    Indrajeet Chaubey

    2010-11-01

    Full Text Available There has been a steady shift towards modeling and model-based approaches as primary methods of assessing watershed response to hydrologic inputs and land management, and of quantifying watershed-wide best management practice (BMP effectiveness. Watershed models often require some degree of calibration and validation to achieve adequate watershed and therefore BMP representation. This is, however, only possible for gauged watersheds. There are many watersheds for which there are very little or no monitoring data available, thus the question as to whether it would be possible to extend and/or generalize model parameters obtained through calibration of gauged watersheds to ungauged watersheds within the same region. This study explored the possibility of developing regionalized model parameter sets for use in ungauged watersheds. The study evaluated two regionalization methods: global averaging, and regression-based parameters, on the SWAT model using data from priority watersheds in Arkansas. Resulting parameters were tested and model performance determined on three gauged watersheds. Nash-Sutcliffe efficiencies (NS for stream flow obtained using regression-based parameters (0.53–0.83 compared well with corresponding values obtained through model calibration (0.45–0.90. Model performance obtained using global averaged parameter values was also generally acceptable (0.4 ≤ NS ≤ 0.75. Results from this study indicate that regionalized parameter sets for the SWAT model can be obtained and used for making satisfactory hydrologic response predictions in ungauged watersheds.

  20. Modeling of discharge and sediment transport through the SWAT model in the basin of Harraza (Northwest of Algeria

    Directory of Open Access Journals (Sweden)

    Faiza Hallouz

    2018-04-01

    Full Text Available The objective of this study is to model discharge and solid erosion quantification through a small agricultural watershed by applying the SWAT model (Soil and Water Assessment Tools on the Wadi Harraza’s basin of which is part of Wadi Cheliff’s basin, with an average altitude of 500 m, drains an area of 568 sq km. Soil and Water Assessment Tool (SWAT, version 2009 model integrated with Geographic Information System (ArcGIS, version 10.0 were used to simulate the discharge and sediment concentration of Wadi Harraza’s basin for the period from 2004 to 2009. Model calibration and validation were performed for monthly time periods using Sequential Uncertainty Fitting 2 (SUFI-2, version 2 within SWAT-CUP. Our calibration and validation outputs for monthly simulation showed a good model performance for discharges. Thus the evolution of the average total annual sediment in the Wadi Harraza’s basin which will be deposited in the Wadi Cheliff, is estimated at 54.24 t ha−1. Keywords: SWAT model, Basin, Wadi Harraza, SUFI-2, Discharges, Sediment

  1. Modeling the impact of nitrogen fertilizer application and tile drain configuration on nitrate leaching using SWAT

    Science.gov (United States)

    Recently, the Soil and Water Assessment Tool (SWAT) was revised to improve the partitioning of runoff and tile drainage in poorly drained soils by modifying the algorithm for computing the soil moisture retention parameter. In this study, the revised SWAT model was used to evaluate the sensitivity a...

  2. Using expert knowledge of the hydrological system to constrain multi-objective calibration of SWAT models

    Science.gov (United States)

    The SWAT model is a helpful tool to predict hydrological processes in a study catchment and their impact on the river discharge at the catchment outlet. For reliable discharge predictions, a precise simulation of hydrological processes is required. Therefore, SWAT has to be calibrated accurately to ...

  3. Streamflow data assimilation in SWAT model using Extended Kalman Filter

    Science.gov (United States)

    Sun, Leqiang; Nistor, Ioan; Seidou, Ousmane

    2015-12-01

    The Extended Kalman Filter (EKF) is coupled with the Soil and Water Assessment Tools (SWAT) model in the streamflow assimilation of the upstream Senegal River in West Africa. Given the large number of distributed variables in SWAT, only the average watershed scale variables are included in the state vector and the Hydrological Response Unit (HRU) scale variables are updated with the a posteriori/a priori ratio of their watershed scale counterparts. The Jacobian matrix is calculated numerically by perturbing the state variables. Both the soil moisture and CN2 are significantly updated in the wet season, yet they have opposite update patterns. A case study for a large flood forecast shows that for up to seven days, the streamflow forecast is moderately improved using the EKF-subsequent open loop scheme but significantly improved with a newly designed quasi-error update scheme. The former has better performances in the flood rising period while the latter has better performances in the recession period. For both schemes, the streamflow forecast is improved more significantly when the lead time is shorter.

  4. Temporal diagnostic analysis of the SWAT model to detect dominant periods of poor model performance

    Science.gov (United States)

    Guse, Björn; Reusser, Dominik E.; Fohrer, Nicola

    2013-04-01

    Hydrological models generally include thresholds and non-linearities, such as snow-rain-temperature thresholds, non-linear reservoirs, infiltration thresholds and the like. When relating observed variables to modelling results, formal methods often calculate performance metrics over long periods, reporting model performance with only few numbers. Such approaches are not well suited to compare dominating processes between reality and model and to better understand when thresholds and non-linearities are driving model results. We present a combination of two temporally resolved model diagnostic tools to answer when a model is performing (not so) well and what the dominant processes are during these periods. We look at the temporal dynamics of parameter sensitivities and model performance to answer this question. For this, the eco-hydrological SWAT model is applied in the Treene lowland catchment in Northern Germany. As a first step, temporal dynamics of parameter sensitivities are analyzed using the Fourier Amplitude Sensitivity test (FAST). The sensitivities of the eight model parameters investigated show strong temporal variations. High sensitivities were detected for two groundwater (GW_DELAY, ALPHA_BF) and one evaporation parameters (ESCO) most of the time. The periods of high parameter sensitivity can be related to different phases of the hydrograph with dominances of the groundwater parameters in the recession phases and of ESCO in baseflow and resaturation periods. Surface runoff parameters show high parameter sensitivities in phases of a precipitation event in combination with high soil water contents. The dominant parameters give indication for the controlling processes during a given period for the hydrological catchment. The second step included the temporal analysis of model performance. For each time step, model performance was characterized with a "finger print" consisting of a large set of performance measures. These finger prints were clustered into

  5. Assessment of Climate Change Impacts on Water Resources in Zarrinehrud Basin Using SWAT Model

    Directory of Open Access Journals (Sweden)

    B. Mansouri

    2015-06-01

    Full Text Available This paper evaluate impacts of climate change on temperature, rainfall and runoff in the future Using statistical model, LARS-WG, and conceptual hydrological model, SWAT. In order to the Zarrinehrud river basin, as the biggest catchment of the Lake Urmia basin was selected as a case study. At first, for the generation of future weather data in the basin, LARS-WG model was calibrated using meteorological data and then 14 models of AOGCM were applied and results of these models were downscaled using LARS-WG model in 6 synoptic stations for period of 2015 to 2030. SWAT model was used for evaluation of climate change impacts on runoff in the basin. In order to, the model was calibrated and validated using 6 gauging stations for period of 1987-2007 and the value of R2 was between 0.49 and 0.71 for calibration and between 0.54 and 0.77 for validation. Then by introducing average of downscaled results of AOGCM models to the SWAT, runoff changes of the basin were simulated during 2015-2030. Average of results of LARS-WG model indicated that the monthly mean of minimum and maximum temperatures will increase compared to the baseline period. Also monthly average of precipitation will decrease in spring season but will increase in summer and autumn. The results showed that in addition to the amount of precipitation, its pattern will change in the future period, too. The results of runoff simulation showed that the amount of inflow to the Zarrinehrud reservoir will reduce 28.4 percent compared to the baseline period.

  6. SWAT Check: A Screening Tool to Assist Users in the Identification of Potential Model Application Problems.

    Science.gov (United States)

    White, Michael J; Harmel, R Daren; Arnold, Jeff G; Williams, Jimmy R

    2014-01-01

    The Soil and Water Assessment Tool (SWAT) is a basin-scale hydrologic model developed by the United States Department of Agriculture Agricultural Research Service. SWAT's broad applicability, user-friendly model interfaces, and automatic calibration software have led to a rapid increase in the number of new users. These advancements also allow less experienced users to conduct SWAT modeling applications. In particular, the use of automated calibration software may produce simulated values that appear appropriate because they adequately mimic measured data used in calibration and validation. Autocalibrated model applications (and often those of unexperienced modelers) may contain input data errors and inappropriate parameter adjustments not readily identified by users or the autocalibration software. The objective of this research was to develop a program to assist users in the identification of potential model application problems. The resulting "SWAT Check" is a stand-alone Microsoft Windows program that (i) reads selected SWAT output and alerts users of values outside the typical range; (ii) creates process-based figures for visualization of the appropriateness of output values, including important outputs that are commonly ignored; and (iii) detects and alerts users of common model application errors. By alerting users to potential model application problems, this software should assist the SWAT community in developing more reliable modeling applications. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  7. Applicability of the SWAT model for hydrologic simulation in Paraopeba river basin, MG

    Directory of Open Access Journals (Sweden)

    Matheus Fonseca Durães

    2011-12-01

    Full Text Available The SWAT model (Soil and Water Assessment Tool was applied for simulating the hydrologic pattern of Paraopeba river basin, in Minas Gerais state, under different land use and occupation scenarios, looking to support basin management actions. The model parameters were calibrated and validated, with respect to the data observed from 1983 to 2005. The basin was assessed at the ‘Porto do Mesquita’ gauging station and change in land use and occupation was based on the annual growth scenarios proposed in the partial report of Paraopeba basin’s master plan. The model was found to be highly sensitive to baseflow, its main calibration variable. Statistical analyses produced a Nash-Sutcliffe coefficient above 0.75, which is considered good and acceptable. The SWAT model provided satisfactory results in simulating hydrologic pattern under different scenarios of land use change, demonstrating that it can be applied for forecasting discharge in the aforesaid basin. The current land use scenario provided a peak discharge simulation of 1250 m³ s-1, while in years 2019 and 2029 peak discharge simulations were 1190 m³ s-1 and 1230 m³ s-1 respectively. The 2019 scenario provided the best results with respect to baseflow increase and peak discharge reduction.

  8. ASSESSMENT OF WATER BALANCE OF A WATERSHED USING SWAT MODEL FOR WATER RESOURCES MANAGEMENT

    OpenAIRE

    Sandra George; Sathian, K.K.

    2016-01-01

    An attempt has been made in this study to assess the hydrological behavior of the Kurumali sub basin of Karuvannur river basin using SWAT model and other geospatial technologies. All the thematic maps and attribute information of the watershed have been collected from various Government agencies. SWAT model has been set up for the Kurumali sub basin by inputting the digital thematic maps, physical properties of soil and climatic parameters. Total area of the watershed corresponding to the out...

  9. SWAT application in intensive irrigation systems: Model modification, calibration and validation

    OpenAIRE

    Dechmi, Farida; Burguete, Javier; Skhiri, Ahmed

    2012-01-01

    The Soil and Water Assessment Tool (SWAT) is a well established, distributed, eco-hydrologic model. However, using the study case of an agricultural intensive irrigated watershed, it was shown that all the model versions are not able to appropriately reproduce the total streamflow in such system when the irrigation source is outside the watershed. The objective of this study was to modify the SWAT2005 version for correctly simulating the main hydrological processes. Crop yield, total streamfl...

  10. Simulation of agricultural non-point source pollution in Xichuan by using SWAT model

    Science.gov (United States)

    Xing, Linan; Zuo, Jiane; Liu, Fenglin; Zhang, Xiaohui; Cao, Qiguang

    2018-02-01

    This paper evaluated the applicability of using SWAT to access agricultural non-point source pollution in Xichuan area. In order to build the model, DEM, soil sort and land use map, climate monitoring data were collected as basic database. The SWAT model was calibrated and validated for the SWAT was carried out using streamflow, suspended solids, total phosphorus and total nitrogen records from 2009 to 2011. Errors, coefficient of determination and Nash-Sutcliffe coefficient were considered to evaluate the applicability. The coefficient of determination were 0.96, 0.66, 0.55 and 0.66 for streamflow, SS, TN, and TP, respectively. Nash-Sutcliffe coefficient were 0.93, 0.5, 0.52 and 0.63, respectively. The results all meet the requirements. It suggested that the SWAT model can simulate the study area.

  11. Ethiopian Central Rift Valley basin hydrologic modelling using HEC-HMS and ArcSWAT

    Science.gov (United States)

    Pascual-Ferrer, Jordi; Candela, Lucila; Pérez-Foguet, Agustí

    2013-04-01

    An Integrated Water Resources Management (IWRM) shall be applied to achieve a sustainable development, to increase population incomes without affecting lives of those who are highly dependent on the environment. First step should be to understand water dynamics at basin level, starting by modeling the basin water resources. For model implementation, a large number of data and parameters are required, but those are not always available, especially in some developing countries where different sources may have different data, there is lack of information on data collection, etc. The Ethiopian Central Rift Valley (CRV) is an endorheic basin covering an area of approximately 10,000 km2. For the period 1996-2005, the average annual volume of rainfall accounted for 9.1 Mm3, and evapotranspiration for 8 Mm3 (Jansen et al., 2007). From the environmental point of view, basin ecosystems are endangered due to human activities. Also, poverty is widespread all over the basin, with population mainly living from agriculture on a subsistence economy. Hence, there is an urgent need to set an IWRM, but datasets required for water dynamics simulation are not too reliable. In order to reduce uncertainty of numerical simulation, two semi-distributed open software hydrologic models were implemented: HEC-HMS and ArcSWAT. HEC-HMS was developed by the United States Army Corps of Engineers (USACoE) Hydrologic Engineering Center (HEC) to run precipitation-runoff simulations for a variety of applications in dendritic watershed systems. ArcSWAT includes the SWAT (Soil and Water Assessment Tool, Arnold et al., 1998) model developed for the USDA Agricultural Research Service into ArcGIS (ESRI®). SWAT was developed to assess the impact of land management practices on large complex watersheds with varying soils, land use and management conditions over long periods of time (Neitsch et al., 2005). According to this, ArcSWAT would be the best option for IWRM implementation in the basin. However

  12. Parameterization and Uncertainty Analysis of SWAT model in Hydrological Simulation of Chaohe River Basin

    Science.gov (United States)

    Jie, M.; Zhang, J.; Guo, B. B.

    2017-12-01

    As a typical distributed hydrological model, the SWAT model also has a challenge in calibrating parameters and analysis their uncertainty. This paper chooses the Chaohe River Basin China as the study area, through the establishment of the SWAT model, loading the DEM data of the Chaohe river basin, the watershed is automatically divided into several sub-basins. Analyzing the land use, soil and slope which are on the basis of the sub-basins and calculating the hydrological response unit (HRU) of the study area, after running SWAT model, the runoff simulation values in the watershed are obtained. On this basis, using weather data, known daily runoff of three hydrological stations, combined with the SWAT-CUP automatic program and the manual adjustment method are used to analyze the multi-site calibration of the model parameters. Furthermore, the GLUE algorithm is used to analyze the parameters uncertainty of the SWAT model. Through the sensitivity analysis, calibration and uncertainty study of SWAT, the results indicate that the parameterization of the hydrological characteristics of the Chaohe river is successful and feasible which can be used to simulate the Chaohe river basin.

  13. Modeling crop water productivity using a coupled SWAT-MODSIM model

    Science.gov (United States)

    This study examines the water productivity of irrigated wheat and maize yields in Karkheh River Basin (KRB) in the semi-arid region of Iran using a coupled modeling approach consisting of the hydrological model (SWAT) and the river basin water allocation model (MODSIM). Dynamic irrigation requireme...

  14. Assessing Thermally Stressful Events in a Rhode Island Coldwater Fish Habitat Using the SWAT Model

    Directory of Open Access Journals (Sweden)

    Britta Chambers

    2017-09-01

    Full Text Available It has become increasingly important to recognize historical water quality trends so that the future impacts of climate change may be better understood. Climate studies have suggested that inland stream temperatures and average streamflow will increase over the next century in New England, thereby putting aquatic species sustained by coldwater habitats at risk. In this study we evaluated two different approaches for modeling historical streamflow and stream temperature in a Rhode Island, USA, watershed with the Soil and Water Assessment Tool (SWAT, using (i original SWAT and (ii SWAT plus a hydroclimatological model component that considers both hydrological inputs and air temperature. Based on daily calibration results with six years of measured streamflow and four years of stream temperature data, we examined occurrences of stressful conditions for brook trout (Salvelinus fontinalis using the hydroclimatological model. SWAT with the hydroclimatological component improved modestly during calibration (NSE of 0.93, R2 of 0.95 compared to the original SWAT (NSE of 0.83, R2 of 0.93. Between 1980–2009, the number of stressful events, a moment in time where high or low flows occur simultaneously with stream temperatures exceeding 21 °C, increased by 55% and average streamflow increased by 60%. This study supports using the hydroclimatological SWAT component and provides an example method for assessing stressful conditions in southern New England’s coldwater habitats.

  15. Assessment of terrain slope influence in SWAT modeling of Andean watersheds

    Science.gov (United States)

    Yacoub, C.; Pérez-Foguet, A.

    2009-04-01

    Hydrological processes in the Andean Region are difficult to model. Large range of altitudes involved (from over 4000 meters above sea level, masl, to zero) indicates the high variability of rainfall, temperature and other climate variables. Strong runoff and extreme events as landslides and floods are the consequence of high slopes of terrain, especially in the upper part of the basins. Strong seasonality of rain and complex ecosystems (vulnerable to climate changes and anthropogenic activities) helps these processes. Present study focuses in a particular watershed from Peruvian Andes, the Jequetepeque River. The distributed watershed simulation model, Soil and Water Assessment Tool (SWAT) is applied to model run-off and sediments transport through the basin with data from 1997 to 2006. Specifically, the study focuses in the assessment of the influence of considering terrain slope variation in the definition of Hydrographical Response Units within SWAT. The Jequetepeque watershed (4 372.5 km2) is located in the north part of Peru. River flows east to west, to the Pacific Ocean. Annual average precipitation ranges from 0 to 1100 mm and altitude from 0 to 4188 masl. The "Gallito Ciego" reservoir (400 masl) separates upper-middle part from lower part of the watershed. It stores water for supplying the people from the big cities on the coast and for extensive agriculture uses. Upper-middle part of the watershed covers 3564.8 km2. It ranges from 400 to 4188 masl in no more that 80 km, with slopes up to 20%. Main activities are agricultural and livestock and mining and about 80% of the population are rural. Annual mean temperature drops from 25.4 °C at the reservoir to less than 4 °C in the upper part. Also the highest rainfall variability is found in the upper-middle part of the watershed. Erosion produced by extreme events like 1997/98 "el Niño" Phenomenon is silting the reservoir faster than expected. Moreover, anthropogenic activities like agriculture and

  16. Evaluation of precipitation input for SWAT modeling in Alpine catchment: A case study in the Adige river basin (Italy).

    Science.gov (United States)

    Tuo, Ye; Duan, Zheng; Disse, Markus; Chiogna, Gabriele

    2016-12-15

    Precipitation is often the most important input data in hydrological models when simulating streamflow. The Soil and Water Assessment Tool (SWAT), a widely used hydrological model, only makes use of data from one precipitation gauge station that is nearest to the centroid of each subbasin, which is eventually corrected using the elevation band method. This leads in general to inaccurate representation of subbasin precipitation input data, particularly in catchments with complex topography. To investigate the impact of different precipitation inputs on the SWAT model simulations in Alpine catchments, 13years (1998-2010) of daily precipitation data from four datasets including OP (Observed precipitation), IDW (Inverse Distance Weighting data), CHIRPS (Climate Hazards Group InfraRed Precipitation with Station data) and TRMM (Tropical Rainfall Measuring Mission) has been considered. Both model performances (comparing simulated and measured streamflow data at the catchment outlet) as well as parameter and prediction uncertainties have been quantified. For all three subbasins, the use of elevation bands is fundamental to match the water budget. Streamflow predictions obtained using IDW inputs are better than those obtained using the other datasets in terms of both model performance and prediction uncertainty. Models using the CHIRPS product as input provide satisfactory streamflow estimation, suggesting that this satellite product can be applied to this data-scarce Alpine region. Comparing the performance of SWAT models using different precipitation datasets is therefore important in data-scarce regions. This study has shown that, precipitation is the main source of uncertainty, and different precipitation datasets in SWAT models lead to different best estimate ranges for the calibrated parameters. This has important implications for the interpretation of the simulated hydrological processes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Annual theme report (October 2007 to September 2008) for the environmental impact (SWAT modeling) component of "Agroforestry and Sustainable Vegetable Production in Southeast Asian Watersheds" project

    OpenAIRE

    Ella, Victor B.

    2008-01-01

    The implementation of the Environmental Impact (SWAT Modeling) component of this SANREM CRSP project in year 3 was highlighted by further work on SWAT model development in Indonesia, Philippines and Vietnam. In all three countries, additional input data have been collected over the past year for SWAT modeling purposes. Data Elevation Models (DEMs), land use maps and soil maps have also been prepared in all three countries. In the Philippines, SWAT model has been developed for assessing the hy...

  18. A Comparison of SWAT and ANN Models for Daily Runoff Simulation in Different Climatic Zones of Peninsular Spain

    Directory of Open Access Journals (Sweden)

    Patricia Jimeno-Sáez

    2018-02-01

    Full Text Available Streamflow data are of prime importance to water-resources planning and management, and the accuracy of their estimation is very important for decision making. The Soil and Water Assessment Tool (SWAT and Artificial Neural Network (ANN models have been evaluated and compared to find a method to improve streamflow estimation. For a more complete evaluation, the accuracy and ability of these streamflow estimation models was also established separately based on their performance during different periods of flows using regional flow duration curves (FDCs. Specifically, the FDCs were divided into five sectors: very low, low, medium, high and very high flow. This segmentation of flow allows analysis of the model performance for every important discharge event precisely. In this study, the models were applied in two catchments in Peninsular Spain with contrasting climatic conditions: Atlantic and Mediterranean climates. The results indicate that SWAT and ANNs were generally good tools in daily streamflow modelling. However, SWAT was found to be more successful in relation to better simulation of lower flows, while ANNs were superior at estimating higher flows in all cases.

  19. Watershed Modeling with ArcSWAT and SUFI2 In Cisadane Catchment Area: Calibration and Validation of River Flow Prediction

    Directory of Open Access Journals (Sweden)

    Iwan Ridwansyah

    2014-04-01

    Full Text Available Increasing of natural resources utilization as a result of population growth and economic development has caused severe damage on the watershed. The impacts of natural disasters such as floods, landslides and droughts become more frequent. Cisadane Catchment Area is one of 108 priority watershed in Indonesia. SWAT is currently applied world wide and considered as a versatile model that can be used to integrate multiple environmental processes, which support more effective watershed management and the development of better informed policy decision. The objective of this study is to examine the applicability of SWAT model for modeling mountainous catchments, focusing on Cisadane catchment Area in west Java Province, Indonesia. The SWAT model simulation was done for the periods of 2005 – 2010 while it used landuse information in 2009. Methods of Sequential Uncertainty Fitting ver. 2 (SUFI2 and combine with manual calibration were used in this study to calibrate a rainfall-runoff. The Calibration is done on 2007 and the validation on 2009, the R2 and Nash Sutchliffe Efficiency (NSE of the calibration were 0.71 and 0.72 respectively and the validation are 0.708 and 0.7 respectively. The monthly average of surface runoff and total water yield from the simulation were 27.7 mm and 2718.4 mm respectively. This study showed SWAT model can be a potential monitoring tool especially for watersheds in Cisadane Catchment Area or in the tropical regions. The model can be used for another purpose, especially in watershed management.

  20. Code modernization and modularization of APEX and SWAT watershed simulation models

    Science.gov (United States)

    SWAT (Soil and Water Assessment Tool) and APEX (Agricultural Policy / Environmental eXtender) are respectively large and small watershed simulation models derived from EPIC Environmental Policy Integrated Climate), a field-scale agroecology simulation model. All three models are coded in FORTRAN an...

  1. Simulation of a low-gradient Coastal Plain watershed using the SWAT landscape model

    Science.gov (United States)

    Accurate representation of landscape processes in natural resource models requires distributed representation of basin hydrology and transport processes. To better represent these processes, a landscape version of the SWAT model has been developed. The model has been modified to represent the runo...

  2. ANALISIS CURAH HUJAN DAN DEBIT MODEL SWAT DENGAN METODE MOVING AVERAGE DI DAS CILIWUNG HULU

    Directory of Open Access Journals (Sweden)

    Defri Satiya Zuma

    2017-09-01

    Full Text Available Watershed can be regarded as a hydrological system that has a function in transforming rainwater as an input into outputs such as flow and sediment. The transformation of inputs into outputs has specific forms and properties. The transformation involves many processes, including processes occurred on the surface of the land, river basins, in soil and aquifer. This study aimed to apply the SWAT model  in  Ciliwung Hulu Watershed, asses the effect of average rainfall  on 3 days, 5 days, 7 days and 10 days of the hydrological characteristics in Ciliwung Hulu Watershed. The correlation coefficient (r between rainfall and discharge was positive, it indicated that there was an unidirectional relationship between rainfall and discharge in the upstream, midstream and downstream of the watershed. The upper limit ratio of discharge had a downward trend from upstream to downstream, while the lower limit ratio of  discharge had an upward trend from upstream to downstream. It showed that the discharge peak in Ciliwung  Hulu Watershed from upstream to downstream had a downward trend while the baseflow from upstream to downstream had an upward trend. It showed that the upstream of Ciliwung Hulu Watershed had the highest ratio of discharge peak  and baseflow so it needs the soil and water conservations and technical civil measures. The discussion concluded that the SWAT model could be well applied in Ciliwung Hulu Watershed, the most affecting average rainfall on the hydrological characteristics was the average rainfall of 10 days. On average  rainfall of 10 days, all components had contributed maximally for river discharge.

  3. Hydrological modeling of the Simly Dam watershed (Pakistan) using GIS and SWAT model

    OpenAIRE

    Shimaa M. Ghoraba

    2015-01-01

    Modern mathematical models have been developed for studying the complex hydrological processes of a watershed and their direct relation to weather, topography, geology and land use. In this study the hydrology of Simly Dam watershed located in Saon River basin at the north-east of Islamabad is modeled, using the Soil and Water Assessment Tool (SWAT). It aims to simulate the stream flow, establish the water balance and estimate the monthly volume inflow to Simly Dam in order to help the manage...

  4. The modified SWAT model for predicting fecal coliforms in the Wachusett Reservoir Watershed, USA.

    Science.gov (United States)

    Cho, Kyung Hwa; Pachepsky, Yakov A; Kim, Joon Ha; Kim, Jung-Woo; Park, Mi-Hyun

    2012-10-01

    This study assessed fecal coliform contamination in the Wachusett Reservoir Watershed in Massachusetts, USA using Soil and Water Assessment Tool (SWAT) because bacteria are one of the major water quality parameters of concern. The bacteria subroutine in SWAT, considering in-stream bacteria die-off only, was modified in this study to include solar radiation-associated die-off and the contribution of wildlife. The result of sensitivity analysis demonstrates that solar radiation is one of the most significant fate factors of fecal coliform. A water temperature-associated function to represent the contribution of beaver activity in the watershed to fecal contamination improved prediction accuracy. The modified SWAT model provides an improved estimate of bacteria from the watershed. Our approach will be useful for simulating bacterial concentrations to provide predictive and reliable information of fecal contamination thus facilitating the implementation of effective watershed management. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Modeling Miscanthus in the soil and water assessment tool (SWAT) to simulate its water quality effects as a bioenergy crop.

    Science.gov (United States)

    Ng, Tze Ling; Eheart, J Wayland; Cai, Ximing; Miguez, Fernando

    2010-09-15

    There is increasing interest in perennial grasses as a renewable source of bioenergy and feedstock for second-generation cellulosic biofuels. The primary objective of this study is to estimate the potential effects on riverine nitrate load of cultivating Miscanthus x giganteus in place of conventional crops. In this study, the Soil and Water Assessment Tool (SWAT) is used to model miscanthus growth and streamwater quality in the Salt Creek watershed in Illinois. SWAT has a built-in crop growth component, but, as miscanthus is relatively new as a potentially commercial crop, data on the SWAT crop growth parameters for the crop are lacking. This leads to the second objective of this study, which is to estimate those parameters to facilitate the modeling of miscanthus in SWAT. Results show a decrease in nitrate load that depends on the percent land use change to miscanthus and the amount of nitrogen fertilizer applied to the miscanthus. Specifically, assuming a nitrogen fertilization rate for miscanthus of 90 kg-N/ha, a 10%, 25%, and 50% land use change to miscanthus will lead to decreases in nitrate load of about 6.4%, 16.5%, and 29.6% at the watershed outlet, respectively. Likewise, nitrate load may be reduced by lowering the fertilizer application rate, but not proportionately. When fertilization drops from 90 to 30 kg-N/ha the difference in nitrate load decrease is less than 1% when 10% of the watershed is miscanthus and less than 6% when 50% of the watershed is miscanthus. It is also found that the nitrate load decrease from converting less than half the watershed to miscanthus from corn and soybean in 1:1 rotation surpasses that from converting the whole watershed to just soybean.

  6. Hydrological modeling of the Simly Dam watershed (Pakistan using GIS and SWAT model

    Directory of Open Access Journals (Sweden)

    Shimaa M. Ghoraba

    2015-09-01

    Full Text Available Modern mathematical models have been developed for studying the complex hydrological processes of a watershed and their direct relation to weather, topography, geology and land use. In this study the hydrology of Simly Dam watershed located in Saon River basin at the north-east of Islamabad is modeled, using the Soil and Water Assessment Tool (SWAT. It aims to simulate the stream flow, establish the water balance and estimate the monthly volume inflow to Simly Dam in order to help the managers to plan and handle this important reservoir. The ArcSWAT interface implemented in the ArcGIS software was used to delineate the study area and its sub-components, combine the data layers and edit the model database. The model was calibrated from 1990 to 2001 and evaluated from 2002 to 2011. Based on four recommended statistical coefficients, the evaluation indicates a good performance for both calibration and validation periods and acceptable agreement between measured and simulated values of both annual and monthly scale discharge. The water balance components were correctly estimated and the Simly Dam inflow was successfully reproduced with Coefficient of Determination (R2 of 0.75. These results revealed that if properly calibrated, SWAT model can be used efficiently in semi-arid regions to support water management policies.

  7. Calibration and validation of the SWAT model for a forested watershed in coastal South Carolina

    Science.gov (United States)

    Devendra M. Amatya; Elizabeth B. Haley; Norman S. Levine; Timothy J. Callahan; Artur Radecki-Pawlik; Manoj K. Jha

    2008-01-01

    Modeling the hydrology of low-gradient coastal watersheds on shallow, poorly drained soils is a challenging task due to the complexities in watershed delineation, runoff generation processes and pathways, flooding, and submergence caused by tropical storms. The objective of the study is to calibrate and validate a GIS-based spatially-distributed hydrologic model, SWAT...

  8. Comparison of HSPF and SWAT models performance for runoff and sediment yield prediction.

    Science.gov (United States)

    Im, Sangjun; Brannan, Kevin M; Mostaghimi, Saied; Kim, Sang Min

    2007-09-01

    A watershed model can be used to better understand the relationship between land use activities and hydrologic/water quality processes that occur within a watershed. The physically based, distributed parameter model (SWAT) and a conceptual, lumped parameter model (HSPF), were selected and their performance were compared in simulating runoff and sediment yields from the Polecat Creek watershed in Virginia, which is 12,048 ha in size. A monitoring project was conducted in Polecat Creek watershed during the period of October 1994 to June 2000. The observed data (stream flow and sediment yield) from the monitoring project was used in the calibration/validations of the models. The period of September 1996 to June 2000 was used for the calibration and October 1994 to December 1995 was used for the validation of the models. The outputs from the models were compared to the observed data at several sub-watershed outlets and at the watershed outlet of the Polecat Creek watershed. The results indicated that both models were generally able to simulate stream flow and sediment yields well during both the calibration/validation periods. For annual and monthly loads, HSPF simulated hydrologic and sediment yield more accurately than SWAT at all monitoring sites within the watershed. The results of this study indicate that both the SWAT and HSPF watershed models performed sufficiently well in the simulation of stream flow and sediment yield with HSPF performing moderately better than SWAT for simulation time-steps greater than a month.

  9. Spatial Mapping of Agricultural Water Productivity Using the SWAT Model

    Science.gov (United States)

    Thokal, Rajesh Tulshiram; Gorantiwar, S. D.; Kothari, Mahesh; Bhakar, S. R.; Nandwana, B. P.

    2015-03-01

    The Sina river basin is facing both episodic and chronic water shortages due to intensive irrigation development. The main objective of this study was to characterize the hydrologic processes of the Sina river basin and assess crop water productivity using the distributed hydrologic model, SWAT. In the simulation year (1998-1999), the inflow to reservoir from upstream side was the major contributor to the reservoir accounting for 92 % of the total required water release for irrigation purpose (119.5 Mm3), while precipitation accounted for 4.1 Mm3. Annual release of water for irrigation was 119.5 Mm3 out of which 54 % water was diverted for irrigation purpose, 26 % was wasted as conveyance loss, average discharge at the command outlet was estimated as 4 % and annual average ground-water recharge coefficient was in the range of 13-17 %. Various scenarios involving water allocation rule were tested with the goal of increasing economic water productivity values in the Sina Irrigation Scheme. Out of those, only most benefited allocation rule is analyzed in this paper. Crop yield varied from 1.98 to 25.9 t/ha, with the majority of the area between 2.14 and 2.78 t/ha. Yield and WP declined significantly in loamy soils of the irrigation command. Crop productivity in the basin was found in the lower range when compared with potential and global values. The findings suggested that there was a potential to improve further. Spatial variations in yield and WP were found to be very high for the crops grown during rabi season, while those were low for the crops grown during kharif season. The crop yields and WP during kharif season were more in the lower reach of the irrigation commands, where loamy soil is more concentrated. Sorghum in both seasons was most profitable. Sorghum fetched net income fivefold that of sunflower, two and half fold of pearl millet and one and half fold of mung beans as far as crop during kharif season were concerned and it fetched fourfold that of

  10. A generalized methodology for identification of threshold for HRU delineation in SWAT model

    Science.gov (United States)

    M, J.; Sudheer, K.; Chaubey, I.; Raj, C.

    2016-12-01

    The distributed hydrological model, Soil and Water Assessment Tool (SWAT) is a comprehensive hydrologic model widely used for making various decisions. The simulation accuracy of the distributed hydrological model differs due to the mechanism involved in the subdivision of the watershed. Soil and Water Assessment Tool (SWAT) considers sub-dividing the watershed and the sub-basins into small computing units known as 'hydrologic response units (HRU). The delineation of HRU is done based on unique combinations of land use, soil types, and slope within the sub-watersheds, which are not spatially defined. The computations in SWAT are done at HRU level and are then aggregated up to the sub-basin outlet, which is routed through the stream system. Generally, the HRUs are delineated by considering a threshold percentage of land use, soil and slope are to be given by the modeler to decrease the computation time of the model. The thresholds constrain the minimum area for constructing an HRU. In the current HRU delineation practice in SWAT, the land use, soil and slope of the watershed within a sub-basin, which is less than the predefined threshold, will be surpassed by the dominating land use, soil and slope, and introduce some level of ambiguity in the process simulations in terms of inappropriate representation of the area. But the loss of information due to variation in the threshold values depends highly on the purpose of the study. Therefore this research studies the effects of threshold values of HRU delineation on the hydrological modeling of SWAT on sediment simulations and suggests guidelines for selecting the appropriate threshold values considering the sediment simulation accuracy. The preliminary study was done on Illinois watershed by assigning different thresholds for land use and soil. A general methodology was proposed for identifying an appropriate threshold for HRU delineation in SWAT model that considered computational time and accuracy of the simulation

  11. Evapotranspiration and Precipitation inputs for SWAT model using remotely sensed observations

    Science.gov (United States)

    The ability of numerical models, such as the Soil and Water Assessment Tool (or SWAT), to accurately represent the partition of the water budget and describe sediment loads and other pollutant conditions related to water quality strongly depends on how well spatiotemporal variability in precipitatio...

  12. Hydrologic evaluation of a Mediterranean watershed using the SWAT model with multiple PET estimation methods

    Science.gov (United States)

    The Penman-Monteith method suggested by the Food Agricultural Organization in the Irrigation and drainage paper 56 (FAO-56 P-M) was used to evaluate surface runoff and sediment yield predictions by the Soil and Water Assessment Tool (SWAT) model at the outlet of an experimental watershed in Sicily. ...

  13. Modeling phosphorus in the Lake Allatoona watershed using SWAT: I. Developing phosphorus parameter values.

    Science.gov (United States)

    Radcliffe, D E; Lin, Z; Risse, L M; Romeis, J J; Jackson, C R

    2009-01-01

    Lake Allatoona is a large reservoir north of Atlanta, GA, that drains an area of about 2870 km2 scheduled for a phosphorus (P) total maximum daily load (TMDL). The Soil and Water Assessment Tool (SWAT) model has been widely used for watershed-scale modeling of P, but there is little guidance on how to estimate P-related parameters, especially those related to in-stream P processes. In this paper, methods are demonstrated to individually estimate SWAT soil-related P parameters and to collectively estimate P parameters related to stream processes. Stream related parameters were obtained using the nutrient uptake length concept. In a manner similar to experiments conducted by stream ecologists, a small point source is simulated in a headwater sub-basin of the SWAT models, then the in-stream parameter values are adjusted collectively to get an uptake length of P similar to the values measured in the streams in the region. After adjusting the in-stream parameters, the P uptake length estimated in the simulations ranged from 53 to 149 km compared to uptake lengths measured by ecologists in the region of 11 to 85 km. Once the a priori P-related parameter set was developed, the SWAT models of main tributaries to Lake Allatoona were calibrated for daily transport. Models using SWAT P parameters derived from the methods in this paper outperformed models using default parameter values when predicting total P (TP) concentrations in streams during storm events and TP annual loads to Lake Allatoona.

  14. Analisis Debit Sungai Dengan Menggunakan Model SWAT pada DAS Cipasauran, Banten

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    Maulana Ibrahim Rau

    2015-10-01

    Full Text Available Total water demand at non industrial and industrial region in Cilegon is increasing. With its water production capacity of 2,000 l/s, PT Krakatau Tirta Industri cannot fulfill the amount number of demand from the industrial and domestic sectors at Cilegon. To cover the shortage of water supply of ±600 l/s, PT KTI requires taking water from Cipasauran Watershed. The objective of this study was to analyze river discharge of Cipasauran Watershed using SWAT model. Input data such as soil characteristics, climate data, landuse, and hydrology data at the area of the watershed were gathered and put at the data input file. In SWAT simulation, 4 processes were done, i.e. watershed delineation, hydrological response unit (HRU forming, data process and SWAT simulation, and visualization process. The result showed that the daily and monthly calibration process crossed 84% and 83% with the 95PPU area, with daily and monthly p-factor value of 0.84 and 0.83. Thus, calibrated model result was valid, though R2 and NS value were not satisfied. Using the validated SWAT model, the daily discharge in Cipasauran Watershed was about 0 - 3.309 m3/s, whereas the monthly discharge was 0.648 - 3.266m3/s. This showed that daily and monthly PT KTI’s water demand of 0.6 m3/s were fulfilled about 98.22% and 100%. Within the future time, the SWAT model could be potentially used as an assessment for predictive scenarios. However, to gain optimum results, well-observed and precise data is highly required, especially for such calibrations and validations.

  15. Automating calibration, sensitivity and uncertainty analysis of complex models using the R package Flexible Modeling Environment (FME): SWAT as an example

    Science.gov (United States)

    Wu, Y.; Liu, S.

    2012-01-01

    Parameter optimization and uncertainty issues are a great challenge for the application of large environmental models like the Soil and Water Assessment Tool (SWAT), which is a physically-based hydrological model for simulating water and nutrient cycles at the watershed scale. In this study, we present a comprehensive modeling environment for SWAT, including automated calibration, and sensitivity and uncertainty analysis capabilities through integration with the R package Flexible Modeling Environment (FME). To address challenges (e.g., calling the model in R and transferring variables between Fortran and R) in developing such a two-language coupling framework, 1) we converted the Fortran-based SWAT model to an R function (R-SWAT) using the RFortran platform, and alternatively 2) we compiled SWAT as a Dynamic Link Library (DLL). We then wrapped SWAT (via R-SWAT) with FME to perform complex applications including parameter identifiability, inverse modeling, and sensitivity and uncertainty analysis in the R environment. The final R-SWAT-FME framework has the following key functionalities: automatic initialization of R, running Fortran-based SWAT and R commands in parallel, transferring parameters and model output between SWAT and R, and inverse modeling with visualization. To examine this framework and demonstrate how it works, a case study simulating streamflow in the Cedar River Basin in Iowa in the United Sates was used, and we compared it with the built-in auto-calibration tool of SWAT in parameter optimization. Results indicate that both methods performed well and similarly in searching a set of optimal parameters. Nonetheless, the R-SWAT-FME is more attractive due to its instant visualization, and potential to take advantage of other R packages (e.g., inverse modeling and statistical graphics). The methods presented in the paper are readily adaptable to other model applications that require capability for automated calibration, and sensitivity and uncertainty

  16. Assessment of the Environmental Fate of the Herbicides Flufenacet and Metazachlor with the SWAT Model.

    Science.gov (United States)

    Fohrer, Nicola; Dietrich, Antje; Kolychalow, Olga; Ulrich, Uta

    2014-01-01

    This study aims to assess the environmental fate of the commonly used herbicides flufenacet and metazachlor in the Northern German Lowlands with the ecohydrological Soil and Water Assessment Tool (SWAT model) and to test the sensitivity of pesticide-related input parameters on the modeled transport dynamics. The river discharge of the Kielstau watershed was calibrated (Nash-Sutcliffe efficiency [NSE], 0.83; = 0.84) and validated (NSE, 0.76; = 0.77) for a daily time step. The environmental fate of metazachlor (NSE, 0.68; = 0.62) and flufenacet (NSE, 0.13; = 0.51) was simulated adequately. In comparison to metazachlor, the simulated flufenacet concentration and loads show a lower model efficiency due to the weaker simulation of the stream flow. The in-stream herbicide loads were less than 0.01% of the applied amount in the observed time period and thus not in conflict with European Environmental Legislation. The sensitivity analysis showed that, besides the accurate simulation of stream flow, the parameterization of the temporal and spatial distribution of the herbicide application throughout the watershed is the key factor for appropriate modeling results, whereas the physicochemical properties of the pesticides play a minor role in the modeling process. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  17. Application of WRF - SWAT OpenMI 2.0 based models integration for real time hydrological modelling and forecasting

    Science.gov (United States)

    Bugaets, Andrey; Gonchukov, Leonid

    2014-05-01

    Intake of deterministic distributed hydrological models into operational water management requires intensive collection and inputting of spatial distributed climatic information in a timely manner that is both time consuming and laborious. The lead time of the data pre-processing stage could be essentially reduced by coupling of hydrological and numerical weather prediction models. This is especially important for the regions such as the South of the Russian Far East where its geographical position combined with a monsoon climate affected by typhoons and extreme heavy rains caused rapid rising of the mountain rivers water level and led to the flash flooding and enormous damage. The objective of this study is development of end-to-end workflow that executes, in a loosely coupled mode, an integrated modeling system comprised of Weather Research and Forecast (WRF) atmospheric model and Soil and Water Assessment Tool (SWAT 2012) hydrological model using OpenMI 2.0 and web-service technologies. Migration SWAT into OpenMI compliant involves reorganization of the model into a separate initialization, performing timestep and finalization functions that can be accessed from outside. To save SWAT normal behavior, the source code was separated from OpenMI-specific implementation into the static library. Modified code was assembled into dynamic library and wrapped into C# class implemented the OpenMI ILinkableComponent interface. Development of WRF OpenMI-compliant component based on the idea of the wrapping web-service clients into a linkable component and seamlessly access to output netCDF files without actual models connection. The weather state variables (precipitation, wind, solar radiation, air temperature and relative humidity) are processed by automatic input selection algorithm to single out the most relevant values used by SWAT model to yield climatic data at the subbasin scale. Spatial interpolation between the WRF regular grid and SWAT subbasins centroid (which are

  18. Simulating Landscape Sediment Transport Capacity by Using a Modified SWAT Model.

    Science.gov (United States)

    Bonumá, Nadia B; Rossi, Colleen G; Arnold, Jeffrey G; Reichert, José M; Minella, Jean P; Allen, Peter M; Volk, Martin

    2014-01-01

    Sediment delivery from hillslopes to rivers is spatially variable and may lead to long-term delays between initial erosion and related sediment yield at the watershed outlet. Consideration of spatial variability is important for developing sound strategies for water quality improvement and soil protection at the watershed scale. Hence, the Soil and Water Assessment Tool (SWAT) was modified and tested in this study to simulate the landscape transport capacity of sediment. The study area was the steeply sloped Arroio Lino watershed in southern Brazil. Observed sediment yield data at the watershed outlet were used to calibrate and validate a modified SWAT model. For the calibration period, the modified model performed better than the unaltered SWAT2009 version; the models achieved Nash-Sutcliffe efficiency (NSE) values of 0.7 and -0.1, respectively. Nash-Sutcliffe efficiencies were less for the validation period, but the modified model's NSE was higher than the unaltered model (-1.4 and -12.1, respectively). Despite the relatively low NSE values, the results of this first test are promising because the model modifications lowered the percent bias in sediment yield from 73 to 18%. Simulation results for the modified model indicated that approximately 60% of the mobilized soil is deposited along the landscape before it reaches the river channels. This research demonstrates the modified model's ability to simulate sediment yield in watersheds with steep slopes. The results suggest that integration of the sediment deposition routine in SWAT increases accuracy in steeper areas while significantly improving its ability to predict the spatial distribution of sediment deposition areas. Further work is needed regarding (i) improved strategies for spatially distributed sediment transport measurements (for improving process knowledge and model evaluation) and (ii) extensive model tests in other well instrumented experimental watersheds with differing topographic configurations

  19. SWAT Model Prediction of Phosphorus Loading in a South Carolina Karst Watershed with a Downstream Embayment

    Science.gov (United States)

    Devendra M. Amatya; Manoj K. Jha; Thomas M. Williams; Amy E. Edwards; Daniel R.. Hitchcock

    2013-01-01

    The SWAT model was used to predict total phosphorus (TP) loadings for a 1555-ha karst watershed—Chapel Branch Creek (CBC)—which drains to a lake via a reservoir-like embayment (R-E). The model was first tested for monthly streamflow predictions from tributaries draining three potential source areas as well as the downstream R-E, followed by TP loadings using data...

  20. Adapting SWAT hillslope erosion model to predict sediment concentrations and yields in large Basins.

    Science.gov (United States)

    Vigiak, Olga; Malagó, Anna; Bouraoui, Fayçal; Vanmaercke, Matthias; Poesen, Jean

    2015-12-15

    The Soil and Water Assessment Tool (SWAT) is used worldwide for water quality assessment and planning. This paper aimed to assess and adapt SWAT hillslope sediment yield model (Modified Universal Soil Loss Equation, MUSLE) for applications in large basins, i.e. when spatial data is coarse and model units are large; and to develop a robust sediment calibration method for large regions. The Upper Danube Basin (132,000km(2)) was used as case study representative of large European Basins. The MUSLE was modified to reduce sensitivity of sediment yields to the Hydrologic Response Unit (HRU) size, and to identify appropriate algorithms for estimating hillslope length (L) and slope-length factor (LS). HRUs gross erosion was broadly calibrated against plot data and soil erosion map estimates. Next, mean annual SWAT suspended sediment concentrations (SSC, mg/L) were calibrated and validated against SSC data at 55 gauging stations (622 station-years). SWAT annual specific sediment yields in subbasin reaches (RSSY, t/km(2)/year) were compared to yields measured at 33 gauging stations (87station-years). The best SWAT configuration combined a MUSLE equation modified by the introduction of a threshold area of 0.01km(2) where L and LS were estimated with flow accumulation algorithms. For this configuration, the SSC residual interquartile was less than +/-15mg/L both for the calibration (1995-2004) and the validation (2005-2009) periods. The mean SSC percent bias for 1995-2009 was 24%. RSSY residual interquartile was within +/-10t/km(2)/year, with a mean RSSY percent bias of 12%. Residuals showed no bias with respect to drainage area, slope, or spatial distribution. The use of multiple data types at multiple sites enabled robust simulation of sediment concentrations and yields of the region. The MUSLE modifications are recommended for use in large basins. Based on SWAT simulations, we present a sediment budget for the Upper Danube Basin. Copyright © 2015. Published by Elsevier B.V.

  1. SWAT application in intensive irrigation systems: Model modification, calibration and validation

    Science.gov (United States)

    Dechmi, Farida; Burguete, Javier; Skhiri, Ahmed

    2012-11-01

    SummaryThe Soil and Water Assessment Tool (SWAT) is a well established, distributed, eco-hydrologic model. However, using the study case of an agricultural intensive irrigated watershed, it was shown that all the model versions are not able to appropriately reproduce the total streamflow in such system when the irrigation source is outside the watershed. The objective of this study was to modify the SWAT2005 version for correctly simulating the main hydrological processes. Crop yield, total streamflow, total suspended sediment (TSS) losses and phosphorus load calibration and validation were performed using field survey information and water quantity and quality data recorded during 2008 and 2009 years in Del Reguero irrigated watershed in Spain. The goodness of the calibration and validation results was assessed using five statistical measures, including the Nash-Sutcliffe efficiency (NSE). Results indicated that the average annual crop yield and actual evapotranspiration estimations were quite satisfactory. On a monthly basis, the values of NSE were 0.90 (calibration) and 0.80 (validation) indicating that the modified model could reproduce accurately the observed streamflow. The TSS losses were also satisfactorily estimated (NSE = 0.72 and 0.52 for the calibration and validation steps). The monthly temporal patterns and all the statistical parameters indicated that the modified SWAT-IRRIG model adequately predicted the total phosphorus (TP) loading. Therefore, the model could be used to assess the impacts of different best management practices on nonpoint phosphorus losses in irrigated systems.

  2. Modeling nitrate-nitrogen load reduction strategies for the des moines river, iowa using SWAT

    Science.gov (United States)

    Schilling, K.E.; Wolter, C.F.

    2009-01-01

    The Des Moines River that drains a watershed of 16,175 km2 in portions of Iowa and Minnesota is impaired for nitrate-nitrogen (nitrate) due to concentrations that exceed regulatory limits for public water supplies. The Soil Water Assessment Tool (SWAT) model was used to model streamflow and nitrate loads and evaluate a suite of basin-wide changes and targeting configurations to potentially reduce nitrate loads in the river. The SWAT model comprised 173 subbasins and 2,516 hydrologic response units and included point and nonpoint nitrogen sources. The model was calibrated for an 11-year period and three basin-wide and four targeting strategies were evaluated. Results indicated that nonpoint sources accounted for 95% of the total nitrate export. Reduction in fertilizer applications from 170 to 50 kg/ha achieved the 38% reduction in nitrate loads, exceeding the 34% reduction required. In terms of targeting, the most efficient load reductions occurred when fertilizer applications were reduced in subbasins nearest the watershed outlet. The greatest load reduction for the area of land treated was associated with reducing loads from 55 subbasins with the highest nitrate loads, achieving a 14% reduction in nitrate loads achieved by reducing applications on 30% of the land area. SWAT model results provide much needed guidance on how to begin implementing load reduction strategies most efficiently in the Des Moines River watershed. ?? 2009 Springer Science+Business Media, LLC.

  3. Modeling nitrate-nitrogen load reduction strategies for the Des Moines River, Iowa using SWAT.

    Science.gov (United States)

    Schilling, Keith E; Wolter, Calvin F

    2009-10-01

    The Des Moines River that drains a watershed of 16,175 km(2) in portions of Iowa and Minnesota is impaired for nitrate-nitrogen (nitrate) due to concentrations that exceed regulatory limits for public water supplies. The Soil Water Assessment Tool (SWAT) model was used to model streamflow and nitrate loads and evaluate a suite of basin-wide changes and targeting configurations to potentially reduce nitrate loads in the river. The SWAT model comprised 173 subbasins and 2,516 hydrologic response units and included point and nonpoint nitrogen sources. The model was calibrated for an 11-year period and three basin-wide and four targeting strategies were evaluated. Results indicated that nonpoint sources accounted for 95% of the total nitrate export. Reduction in fertilizer applications from 170 to 50 kg/ha achieved the 38% reduction in nitrate loads, exceeding the 34% reduction required. In terms of targeting, the most efficient load reductions occurred when fertilizer applications were reduced in subbasins nearest the watershed outlet. The greatest load reduction for the area of land treated was associated with reducing loads from 55 subbasins with the highest nitrate loads, achieving a 14% reduction in nitrate loads achieved by reducing applications on 30% of the land area. SWAT model results provide much needed guidance on how to begin implementing load reduction strategies most efficiently in the Des Moines River watershed.

  4. Evaluation of nutrient retention in vegetated filter strips using the SWAT model.

    Science.gov (United States)

    Elçi, Alper

    2017-11-01

    Nutrient fluxes in stream basins need to be controlled to achieve good water quality status. In stream basins with intensive agricultural activities, nutrients predominantly come from diffuse sources. Therefore, best management practices (BMPs) are increasingly implemented to reduce nutrient input to streams. The objective of this study is to evaluate the impact of vegetated filter strip (VFS) application as an agricultural BMP. For this purpose, SWAT is chosen, a semi-distributed water quality assessment model that works at the watershed scale, and applied on the Nif stream basin, a small-sized basin in Western Turkey. The model is calibrated with an automated procedure against measured monthly discharge data. Nutrient loads for each sub-basin are estimated considering basin-wide data on chemical fertilizer and manure usage, population data for septic tank effluents and information about the land cover. Nutrient loads for 19 sub-basins are predicted on an annual basis. Average total nitrogen and total phosphorus loads are estimated as 47.85 t/yr and 13.36 t/yr for the entire basin. Results show that VFS application in one sub-basin offers limited retention of nutrients and that a selection of 20-m filter width is most effective from a cost-benefit perspective.

  5. Improving streamflow simulations and forecasting performance of SWAT model by assimilating remotely sensed soil moisture observations

    Science.gov (United States)

    Patil, Amol; Ramsankaran, RAAJ

    2017-12-01

    This article presents a study carried out using EnKF based assimilation of coarser-scale SMOS soil moisture retrievals to improve the streamflow simulations and forecasting performance of SWAT model in a large catchment. This study has been carried out in Munneru river catchment, India, which is about 10,156 km2. In this study, an EnkF based new approach is proposed for improving the inherent vertical coupling of soil layers of SWAT hydrological model during soil moisture data assimilation. Evaluation of the vertical error correlation obtained between surface and subsurface layers indicates that the vertical coupling can be improved significantly using ensemble of soil storages compared to the traditional static soil storages based EnKF approach. However, the improvements in the simulated streamflow are moderate, which is due to the limitations in SWAT model in reflecting the profile soil moisture updates in surface runoff computations. Further, it is observed that the durability of streamflow improvements is longer when the assimilation system effectively updates the subsurface flow component. Overall, the results of the present study indicate that the passive microwave-based coarser-scale soil moisture products like SMOS hold significant potential to improve the streamflow estimates when assimilating into large-scale distributed hydrological models operating at a daily time step.

  6. Transforming SWAT for continental-scale high-resolution modeling of floodplain dynamics: opportunities and challenges

    Science.gov (United States)

    Rajib, A.; Merwade, V.; Liu, Z.; Lane, C.; Golden, H. E.; Tavakoly, A. A.; Follum, M. L.

    2017-12-01

    There have been many initiatives to develop frameworks for continental-scale modeling and mapping floodplain dynamics. The choice of a model for such needs should be governed by its suitability to be executed in high performance cyber platforms, ability to integrate supporting hydraulic/hydrodynamic tools, and ability to assimilate earth observations. Furthermore, disseminating large volume of outputs for public use and interoperability with similar frameworks should be considered. Considering these factors, we have conducted a series of modeling experiments and developed a suite of cyber-enabled platforms that have transformed Soil and Water Assessment Tool (SWAT) into an appropriate model for use in a continental-scale, high resolution, near real-time flood information framework. Our first experiment uses a medium size watershed in Indiana, USA and attempts burning-in a high resolution, National Hydrography Dataset Plus(NHDPlus) into the SWAT model. This is crucial with a view to make the outputs comparable with other global/national initiatives. The second experiment is built upon the first attempt to add a modified landscape representation in the model which differentiates between the upland and floodplain processes. Our third experiment involves two separate efforts: coupling SWAT with a hydrodynamic model LISFLOOD-FP and a new generation, low complexity hydraulic model AutoRoute. We have executed the prototype "loosely-coupled" models for the Upper Mississippi-Ohio River Basin in the USA, encompassing 1 million square km drainage area and nearly 0.2 million NHDPlus river reaches. The preliminary results suggest reasonable accuracy for both streamflow and flood inundation. In this presentation, we will also showcase three cyber-enabled platforms, including SWATShare to run and calibrate large scale SWAT models online using high performance computational resources, HydroGlobe to automatically extract and assimilate multiple remotely sensed earth observations in

  7. Estimation of transported pollutant load in Ardila catchment using the SWAT model

    OpenAIRE

    DURÃO, A.; LEITÃO, P.; BRITO, D.; FERNANDES, R.M.; NEVES, R.; MORAIS, M.

    2011-01-01

    Excess of organic matter and nutrients in the water body promotes algae blooms, which can accelerate the eutrophication process, situation often observed in the Ardila river. This river was identified as very polluted and classified as critical for Alqueva-Pedrogão System. The aim of this study was to estimate the transported nutrients load in a transboundary catchment using the SWAT (Soil and Water Assessment Tool) model and to determine the contribution off nutrients load in the entire catc...

  8. Spatial and temporal changes of water quality, and SWAT modeling of Vosvozis river basin, North Greece.

    Science.gov (United States)

    Boskidis, Ioannis; Gikas, Georgios D; Pisinaras, Vassilios; Tsihrintzis, Vassilios A

    2010-09-01

    The results of an investigation of the quantitative and qualitative characteristics of Vosvozis river in Northern Greece is presented. For the purposes of this study, three gaging stations were installed along Vosvozis river, where water quantity and quality measurements were conducted for the period August 2005 to November 2006. Water discharge, temperature, pH, dissolved oxygen (DO) and electrical conductivity (EC) were measured in situ using appropriate equipment. The collected water samples were analyzed in the laboratory for the determination of nitrate, nitrite and ammonium nitrogen, total Kjeldalh nitrogen (TKN), orthophosphate (OP), total phosphorus (TP), COD, and BOD. Agricultural diffuse sources provided the major source of nitrate nitrogen loads during the wet period. During the dry period (from June to October), the major nutrient (N, P) and COD, BOD sources were point sources. The trophic status of Vosvozis river during the monitoring period was determined as eutrophic, based on Dodds classification scheme. Moreover, the SWAT model was used to simulate hydrographs and nutrient loads. SWAT was validated with the measured data. Predicted hydrographs and pollutographs were plotted against observed values and showed good agreement. The validated model was used to test eight alternative scenarios concerning different cropping management approaches. The results of these scenarios indicate that nonpoint source pollution is the prevailing type of pollution in the study area. The SWAT model was found to satisfactorily simulate processes in ephemeral river basins and is an effective tool in water resources management.

  9. Assessment of soil erosion risk in Komering watershed, South Sumatera, using SWAT model

    Science.gov (United States)

    Salsabilla, A.; Kusratmoko, E.

    2017-07-01

    Changes in land use watershed led to environmental degradation. Estimated loss of soil erosion is often difficult due to some factors such as topography, land use, climate and human activities. This study aims to predict soil erosion hazard and sediment yield using the Soil and Water Assessment Tools (SWAT) hydrological model. The SWAT was chosen because it can simulate the model with limited data. The study area is Komering watershed (806,001 Ha) in South Sumatera Province. There are two factors land management intervention: 1) land with agriculture, and 2) land with cultivation. These factors selected in accordance with the regulations of spatial plan area. Application of the SWAT demonstrated that the model can predict surface runoff, soil erosion loss and sediment yield. The erosion risk for each watershed can be classified and predicted its changes based on the scenarios which arranged. In this paper, we also discussed the relationship between the distribution of erosion risk and watershed's characteristics in a spatial perspective.

  10. Application of the SWAT model to an endorheic watershed in the Central Spanish Pre-Pyrenees: Methodological approach and preliminary results

    Science.gov (United States)

    Gaspar, Leticia; White, Sue; Navas, Ana; López-Vicente, Manuel; Palazón, Leticia

    2013-04-01

    Modelling runoff and sediment transport at watershed scale are key tools to predict hydrological and sediment processes, identify soil sediment sources and estimate sediment yield, with the purpose of better managing soil and water resources. This study aims to apply the SWAT model in an endorheic watershed in the Central Spanish Pre-Pyrenees, where there have been a number of previous field-based studies on sediment sources and transfers. The Soil and Water Assessment Tool (SWAT) is a process based semi-distributed watershed scale hydrologic model, which can provide a high level of spatial detail by allowing the watershed to be divided into sub-basins. This study addresses the challenge of applying the SWAT model to an endorheic watershed that drains to a central lake, without external output, and without a network of permanent rivers. In this case it has been shown that the SWAT model does not correctly reproduce the stream network when using automatic watershed delineation, even with a high resolution Digital Elevation Model (5 x 5 metres). For this purpose, different approaches needed to be considered, such as i) user-defined watersheds and streams, ii) burning in a stream network or iii) modelling each sub-watershed separately. The objective of this study was to develop a new methodological approach for correctly simulating the main hydrological processes in an endorheic and complex karst watershed of the Spanish Pre-Pyrenees. The Estanque de Arriba Lake watershed (74 ha) is an endorheic system located in the Spanish Central Pre-Pyrenees. This watershed holds a small and permanent lake of fresh water (1.7 ha) and is a Site of Community Importance (European NATURA 2000 network). The study area is characterized by an abrupt topography with altitude range between 679 and 862 m and an average slope gradient of 24 %. Steep slopes (> 24 %) occupy the northern part of the watershed, whereas gentle slopes (

  11. Baseflow simulation using SWAT model in an inland river basin in Tianshan Mountains, Northwest China

    Directory of Open Access Journals (Sweden)

    Y. Luo

    2012-04-01

    Full Text Available Baseflow is an important component in hydrological modeling. The complex streamflow recession process complicates the baseflow simulation. In order to simulate the snow and/or glacier melt dominated streamflow receding quickly during the high-flow period but very slowly during the low-flow period in rivers in arid and cold northwest China, the current one-reservoir baseflow approach in SWAT (Soil Water Assessment Tool model was extended by adding a slow- reacting reservoir and applying it to the Manas River basin in the Tianshan Mountains. Meanwhile, a digital filter program was employed to separate baseflow from streamflow records for comparisons. Results indicated that the two-reservoir method yielded much better results than the one-reservoir one in reproducing streamflow processes, and the low-flow estimation was improved markedly. Nash-Sutcliff efficiency values at the calibration and validation stages are 0.68 and 0.62 for the one-reservoir case, and 0.76 and 0.69 for the two-reservoir case. The filter-based method estimated the baseflow index as 0.60, while the model-based as 0.45. The filter-based baseflow responded almost immediately to surface runoff occurrence at onset of rising limb, while the model-based responded with a delay. In consideration of watershed surface storage retention and soil freezing/thawing effects on infiltration and recharge during initial snowmelt season, a delay response is considered to be more reasonable. However, a more detailed description of freezing/thawing processes should be included in soil modules so as to determine recharge to aquifer during these processes, and thus an accurate onset point of rising limb of the simulated baseflow.

  12. Integrasi Model SWAT dan SIG dalam Upaya Menekan Laju Erosi DAD Deli, Sumatera Utara

    Directory of Open Access Journals (Sweden)

    Riki Rahmad

    2017-04-01

    Full Text Available Penelitian ini bertujuan untuk melakukan simulasi model SWAT dalam menghitung besarnya laju erosi DAS, menguji kesesuaian model dalam memprediksi erosi, serta menentukan skenario penggunaan lahan yang paling optimal menurunkan laju erosi. Penelitian ini dilakukan di DAS Deli, Sumatera Utara. Pada penelitian ini analisis SWAT dilakukan dengan bantuan Sistem Informasi Geografi (SIG melalui 4 proses yaitu delineasi, pembentukan Hydrological Response Unit (HRU, pengolahan data dan simulasi, serta proses visualisasi. Hasil penelitian menunjukkan besarnya erosi rata-rata DAS Deli adalah 410,72 ton/ha/tahun. Hasil ini menunjukkan DAS Deli termasuk kedalam Tingkat Bahaya Erosi (TBE kategori Berat dengan kriteria sangat berat 37,04%, berat 17,07%, sedang 21,46%, ringan 17,38%, dan sangat ringan 7,04%. Uji validasi model menunjukkan bahwa ada hubungan positif antara debit model dan observasi dimana persentase perbedaan nilainya sangat kecil yang artinya besarnya debit model hampir sangat mendekati besarnya debit observasi, serta model dikategorikan sangat baik dalam melakukan simulasi debit aliran harian pada Sungai Deli. Metode skenario adalah berdasarkan analisis TBE. Hasil skenario penggunaan lahan berhasil menurunkan laju erosi DAS Deli 34,78% menjadi 267,88 ton/ha/tahun. This study aims to conduct SWAT model simulation calculation of the rate of erosion of the watershed, testing the suitability of the model in predicting erosion, land use scenarios and determine the most optimal decrease the rate of erosion. This research was conducted in the watershed Deli, North Sumatra. In this study, SWAT analysis performed with the help of Geographical Information Systems (GIS through 4 delineation process, namely, the establishment of Hydrological Response Unit (HRU, data processing and simulation, as well as the visualization process. The results show the average amount of erosion DAS Deli is 410.72 ton/ha/year. These results indicate DAS Deli included into

  13. Trail Creek II: Modeling Flow and E. Coli Concentrations in a Small Urban Stream using SWAT

    Science.gov (United States)

    Radcliffe, D. E.; Saintil, T.

    2017-12-01

    Pathogens are one of the leading causes of stream and river impairment in the State of Georgia. The common presence of fecal bacteria is driven by several factors including rapid population growth stressing pre-existing and ageing infrastructure, urbanization and poor planning, increase percent imperviousness, urban runoff, municipal discharges, sewage, pet/wildlife waste and leaky septic tanks. The Trail Creek watershed, located in Athens-Clarke County, Georgia covers about 33 km2. Stream segments within Trail Creek violate the GA standard due to high levels of fecal coliform bacteria. In this study, the Soil and Water Assessment Tool (SWAT) modeling software was used to predict E. coli bacteria concentrations during baseflow and stormflow. Census data from the county was used for human and animal population estimates and the Fecal Indicator Tool to generate the number of colony forming units of E. Coli for each source. The model was calibrated at a daily time step with one year of monitored streamflow and E. coli bacteria data using SWAT-CUP and the SUFI2 algorithm. To simulate leaking sewer lines, we added point sources in the five subbasins in the SWAT model with the greatest length of sewer line within 50 m of the stream. The flow in the point sources were set to 5% of the stream flow and the bacteria count set to that of raw sewage (30,000 cfu/100 mL). The calibrated model showed that the average load during 2003-2013 at the watershed outlet was 13 million cfu per month. Using the calibrated model, we simulated scenarios that assumed leaking sewers were repaired in one of the five subbasins with point sources. The reduction ranged from 10 to 46%, with the largest reduction in subbasin in the downtown area. Future modeling work will focus on the use of green infrastructure to address sources of bacteria.

  14. SWAT meta-modeling as support of the management scenario analysis in large watersheds.

    Science.gov (United States)

    Azzellino, A; Çevirgen, S; Giupponi, C; Parati, P; Ragusa, F; Salvetti, R

    2015-01-01

    In the last two decades, numerous models and modeling techniques have been developed to simulate nonpoint source pollution effects. Most models simulate the hydrological, chemical, and physical processes involved in the entrainment and transport of sediment, nutrients, and pesticides. Very often these models require a distributed modeling approach and are limited in scope by the requirement of homogeneity and by the need to manipulate extensive data sets. Physically based models are extensively used in this field as a decision support for managing the nonpoint source emissions. A common characteristic of this type of model is a demanding input of several state variables that makes the calibration and effort-costing in implementing any simulation scenario more difficult. In this study the USDA Soil and Water Assessment Tool (SWAT) was used to model the Venice Lagoon Watershed (VLW), Northern Italy. A Multi-Layer Perceptron (MLP) network was trained on SWAT simulations and used as a meta-model for scenario analysis. The MLP meta-model was successfully trained and showed an overall accuracy higher than 70% both on the training and on the evaluation set, allowing a significant simplification in conducting scenario analysis.

  15. An Assessment of Mean Areal Precipitation Methods on Simulated Stream Flow: A SWAT Model Performance Assessment

    Directory of Open Access Journals (Sweden)

    Sean Zeiger

    2017-06-01

    Full Text Available Accurate mean areal precipitation (MAP estimates are essential input forcings for hydrologic models. However, the selection of the most accurate method to estimate MAP can be daunting because there are numerous methods to choose from (e.g., proximate gauge, direct weighted average, surface-fitting, and remotely sensed methods. Multiple methods (n = 19 were used to estimate MAP with precipitation data from 11 distributed monitoring sites, and 4 remotely sensed data sets. Each method was validated against the hydrologic model simulated stream flow using the Soil and Water Assessment Tool (SWAT. SWAT was validated using a split-site method and the observed stream flow data from five nested-scale gauging sites in a mixed-land-use watershed of the central USA. Cross-validation results showed the error associated with surface-fitting and remotely sensed methods ranging from −4.5 to −5.1%, and −9.8 to −14.7%, respectively. Split-site validation results showed the percent bias (PBIAS values that ranged from −4.5 to −160%. Second order polynomial functions especially overestimated precipitation and subsequent stream flow simulations (PBIAS = −160 in the headwaters. The results indicated that using an inverse-distance weighted, linear polynomial interpolation or multiquadric function method to estimate MAP may improve SWAT model simulations. Collectively, the results highlight the importance of spatially distributed observed hydroclimate data for precipitation and subsequent steam flow estimations. The MAP methods demonstrated in the current work can be used to reduce hydrologic model uncertainty caused by watershed physiographic differences.

  16. Modelling of hydrologic processes and potential response to climate change through the use of a multisite SWAT

    DEFF Research Database (Denmark)

    Gül, G.O.; Rosbjerg, Dan

    2010-01-01

    Hydrologic models that use components for integrated modelling of surface water and groundwater systems help conveniently simulate the dynamically linked hydrologic and hydraulic processes that govern flow conditions in watersheds. The Soil and Water Assessment Tool (SWAT) is one such model...... that allows continuous simulations over long time periods in the land phase of the hydrologic cycle by incorporating surface water and groundwater interactions. This study provides a verified structure for the SWAT to evaluate existing flow regimes in a small-sized catchment in Denmark and examines a simple...... simulation to help quantify the effects of climate change on regional water quantities. SWAT can be regarded among the alternative hydrologic simulation tools applicable for catchments with similar characteristics and of similar sizes in Denmark. However, the modellers would be required to determine a proper...

  17. Simulating Crop Evapotranspiration Response under Different Planting Scenarios by Modified SWAT Model in an Irrigation District, Northwest China.

    Science.gov (United States)

    Liu, Xin; Wang, Sufen; Xue, Han; Singh, Vijay P

    2015-01-01

    Modelling crop evapotranspiration (ET) response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1) and summer maize (scenario 2) by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China.

  18. Simulating Crop Evapotranspiration Response under Different Planting Scenarios by Modified SWAT Model in an Irrigation District, Northwest China.

    Directory of Open Access Journals (Sweden)

    Xin Liu

    Full Text Available Modelling crop evapotranspiration (ET response to different planting scenarios in an irrigation district plays a significant role in optimizing crop planting patterns, resolving agricultural water scarcity and facilitating the sustainable use of water resources. In this study, the SWAT model was improved by transforming the evapotranspiration module. Then, the improved model was applied in Qingyuan Irrigation District of northwest China as a case study. Land use, soil, meteorology, irrigation scheduling and crop coefficient were considered as input data, and the irrigation district was divided into subdivisions based on the DEM and local canal systems. On the basis of model calibration and verification, the improved model showed better simulation efficiency than did the original model. Therefore, the improved model was used to simulate the crop evapotranspiration response under different planting scenarios in the irrigation district. Results indicated that crop evapotranspiration decreased by 2.94% and 6.01% under the scenarios of reducing the planting proportion of spring wheat (scenario 1 and summer maize (scenario 2 by keeping the total cultivated area unchanged. However, the total net output values presented an opposite trend under different scenarios. The values decreased by 3.28% under scenario 1, while it increased by 7.79% under scenario 2, compared with the current situation. This study presents a novel method to estimate crop evapotranspiration response under different planting scenarios using the SWAT model, and makes recommendations for strategic agricultural water management planning for the rational utilization of water resources and development of local economy by studying the impact of planting scenario changes on crop evapotranspiration and output values in the irrigation district of northwest China.

  19. Modification of SWAT model for simulation of organic matter in Korean watersheds.

    Science.gov (United States)

    Jang, Jae-Ho; Jung, Kwang-Wook; Gyeong Yoon, Chun

    2012-01-01

    The focus of water quality modeling of Korean streams needs to be shifted from dissolved oxygen to algae or organic matter. In particular, the structure of water quality models should be modified to simulate the biochemical oxygen demand (BOD), which is a key factor in calculating total maximum daily loads (TMDLs) in Korea, using 5-day BOD determined in the laboratory (Bottle BOD(5)). Considering the limitations in simulating organic matter under domestic conditions, we attempted to model total organic carbon (TOC) as well as BOD by using a watershed model. For this purpose, the Soil and Water Assessment Tool (SWAT) model was modified and extended to achieve better correspondence between the measured and simulated BOD and TOC concentrations. For simulated BOD in the period 2004-2008, the Nash-Sutcliffe model efficiency coefficient increased from a value of -2.54 to 0.61. Another indicator of organic matter, namely, the simulated TOC concentration showed that the modified SWAT adequately reflected the observed values. The improved model can be used to predict organic matter and hence, may be a potential decision-making tool for TMDLs. However, it needs further testing for longer simulation periods and other catchments.

  20. Evaluating the Efficiency of a Multi-core Aware Multi-objective Optimization Tool for Calibrating the SWAT Model

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, X. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Izaurralde, R. C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zong, Z. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zhao, K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thomson, A. M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2012-08-20

    The efficiency of calibrating physically-based complex hydrologic models is a major concern in the application of those models to understand and manage natural and human activities that affect watershed systems. In this study, we developed a multi-core aware multi-objective evolutionary optimization algorithm (MAMEOA) to improve the efficiency of calibrating a worldwide used watershed model (Soil and Water Assessment Tool (SWAT)). The test results show that MAMEOA can save about 1-9%, 26-51%, and 39-56% time consumed by calibrating SWAT as compared with sequential method by using dual-core, quad-core, and eight-core machines, respectively. Potential and limitations of MAMEOA for calibrating SWAT are discussed. MAMEOA is open source software.

  1. Calibration and validation of SWAT model for estimating water balance and nitrogen losses in a small agricultural watershed in central Poland

    Directory of Open Access Journals (Sweden)

    Smarzyńska Karolina

    2016-06-01

    Full Text Available Soil and Water Assessment Tool (SWAT ver. 2005 was applied to study water balance and nitrogen load pathways in a small agricultural watershed in the lowlands of central Poland. The natural flow regime of the Zgłowiączka River was strongly modified by human activity (deforestation and installation of a subsurface drainage system to facilitate stable crop production. SWAT was calibrated for daily and monthly discharge and monthly nitrate nitrogen load. Model efficiency was tested using manual techniques (subjective and evaluation statistics (objective. Values of Nash–Sutcliffe efficiency coefficient (NSE, coefficient of determination (R2 and percentage of bias for daily/monthly discharge simulations and monthly load indicated good or very good fit of simulated discharge and nitrate nitrogen load to the observed data set. Model precision and accuracy of fit was proved in validation. The calibrated and validated SWAT was used to assess water balance and nitrogen fluxes in the watershed. According to the results, the share of tile drainage in water yield is equal to 78%. The model analysis indicated the most significant pathway of NO3-N to surface waters in the study area, namely the tile drainage combined with lateral flow. Its share in total NO3-N load amounted to 89%. Identification of nitrogen fluxes in the watershed is crucial for decision makers in order to manage water resources and to implement the most effective measures to limit diffuse pollution from arable land to surface waters.

  2. Incorporating rainfall uncertainty in a SWAT model: the river Zenne basin (Belgium) case study

    Science.gov (United States)

    Tolessa Leta, Olkeba; Nossent, Jiri; van Griensven, Ann; Bauwens, Willy

    2013-04-01

    The European Union Water Framework Directive (EU-WFD) called its member countries to achieve a good ecological status for all inland and coastal water bodies by 2015. According to recent studies, the river Zenne (Belgium) is far from this objective. Therefore, an interuniversity and multidisciplinary project "Towards a Good Ecological Status in the river Zenne (GESZ)" was launched to evaluate the effects of wastewater management plans on the river. In this project, different models have been developed and integrated using the Open Modelling Interface (OpenMI). The hydrologic, semi-distributed Soil and Water Assessment Tool (SWAT) is hereby used as one of the model components in the integrated modelling chain in order to model the upland catchment processes. The assessment of the uncertainty of SWAT is an essential aspect of the decision making process, in order to design robust management strategies that take the predicted uncertainties into account. Model uncertainty stems from the uncertainties on the model parameters, the input data (e.g, rainfall), the calibration data (e.g., stream flows) and on the model structure itself. The objective of this paper is to assess the first three sources of uncertainty in a SWAT model of the river Zenne basin. For the assessment of rainfall measurement uncertainty, first, we identified independent rainfall periods, based on the daily precipitation and stream flow observations and using the Water Engineering Time Series PROcessing tool (WETSPRO). Secondly, we assigned a rainfall multiplier parameter for each of the independent rainfall periods, which serves as a multiplicative input error corruption. Finally, we treated these multipliers as latent parameters in the model optimization and uncertainty analysis (UA). For parameter uncertainty assessment, due to the high number of parameters of the SWAT model, first, we screened out its most sensitive parameters using the Latin Hypercube One-factor-At-a-Time (LH-OAT) technique

  3. Runoff Simulation in the Upper Reaches of Heihe River Basin Based on the RIEMS–SWAT Model

    Directory of Open Access Journals (Sweden)

    Songbing Zou

    2016-10-01

    Full Text Available In the distributed hydrological simulations for complex mountain areas, large amounts of meteorological input parameters with high spatial and temporal resolutions are necessary. However, the extreme scarcity and uneven distribution of the traditional meteorological observation stations in cold and arid regions of Northwest China makes it very difficult in meeting the requirements of hydrological simulations. Alternatively, regional climate models (RCMs, which can provide a variety of distributed meteorological data with high temporal and spatial resolution, have become an effective solution to improve hydrological simulation accuracy and to further study water resource responses to human activities and global climate change. In this study, abundant and evenly distributed virtual weather stations in the upper reaches of the Heihe River Basin (HRB of Northwest China were built for the optimization of the input data, and thus a regional integrated environmental model system (RIEMS based on RCM and a distributed hydrological model of soil and water assessment tool (SWAT were integrated as a coupled climate–hydrological RIEMS-SWAT model, which was applied to simulate monthly runoff from 1995 to 2010 in the region. Results show that the simulated and observed values are close; Nash–Sutcliffe efficiency is higher than 0.65; determination coefficient (R2 values are higher than 0.70; percent bias is controlled within ±20%; and root-mean-square-error-observation standard deviation ratio is less than 0.65. These results indicate that the coupled model can present basin hydrological processes properly, and provide scientific support for prediction and management of basin water resources.

  4. Development of Web-Based RECESS Model for Estimating Baseflow Using SWAT

    Directory of Open Access Journals (Sweden)

    Gwanjae Lee

    2014-04-01

    Full Text Available Groundwater has received increasing attention as an important strategic water resource for adaptation to climate change. In this regard, the separation of baseflow from streamflow and the analysis of recession curves make a significant contribution to integrated river basin management. The United States Geological Survey (USGS RECESS model adopting the master-recession curve (MRC method can enhance the accuracy with which baseflow may be separated from streamflow, compared to other baseflow-separation schemes that are more limited in their ability to reflect various watershed/aquifer characteristics. The RECESS model has been widely used for the analysis of hydrographs, but the applications using RECESS were only available through Microsoft-Disk Operating System (MS-DOS. Thus, this study aims to develop a web-based RECESS model for easy separation of baseflow from streamflow, with easy applications for ungauged regions. RECESS on the web derived the alpha factor, which is a baseflow recession constant in the Soil Water Assessment Tool (SWAT, and this variable was provided to SWAT as the input. The results showed that the alpha factor estimated from the web-based RECESS model improved the predictions of streamflow and recession. Furthermore, these findings showed that the baseflow characteristics of the ungauged watersheds were influenced by the land use and slope angle of watersheds, as well as by precipitation and streamflow.

  5. Evaluation of the applicability of the SWAT model in an arid piedmont plain oasis.

    Science.gov (United States)

    Wu, Yong; Li, Changyou; Zhang, Chengfu; Shi, Xiaohong; Bourque, Charles P-A; Zhao, Shengnan

    2016-01-01

    Hetao Oasis is located in a typical piedmont alluvial plain bounded by the Langshan Mountain Range in the north, desert in the west, and the Yellow River in the south. Agricultural activities within the oasis significantly impact the hydrological cycle and water quality in downstream locations. The research uses the Soil and Water Assessment Tool (SWAT) for a piedmont plain by defining the watershed boundary as coinciding with the natural mountain ridge, the border between the oasis and the desert, and the Yellow River. The model simulates water discharge with coefficient of determination and a Nash-Sutcliffe model efficiency of 0.78 and 0.62 during model calibration, and 0.75 and 0.69 during model validation, suggesting that delineation of the watershed as carried out in this research is suitable for piedmont plain topography. From the results, the mountains contribute 28.4% to the water discharge at the outlet of the watershed, and water-use efficiency of irrigated water is about 40%, which is consistent with field-based measurements. Methodologies used in delineating watershed boundaries and parameterizing SWAT provide a solid foundation for water balance studies in other regions of the world with similar topography.

  6. Calibration and validation of the SWAT model for predicting daily ET over irrigated crops in the Texas High Plains using lysimetric data

    Science.gov (United States)

    The Soil Water Assessment Tool (SWAT) is a widely used watershed model for simulating stream flow, overland flow, sediment, pesticide, and bacterial loading in response to management practices. All SWAT processes are directly dependent upon the accurate representation of hydrology. Evapotranspiratio...

  7. Calibration and validation of the SWAT model for predicting daily ET for irrigated crops in the Texas High Plains using lysimetric data

    Science.gov (United States)

    The Soil and Water Assessment Tool (SWAT) model has been used to assess the impacts of alternative agricultural management practices on non-point source pollution in watersheds of various topography and scale throughout the world. Water balance is the driving force behind all processes of SWAT, as i...

  8. Aplicación del modelo hidrológico-swat-en una microcuenca agrícola de La Pampa ondulada Application of the hydrologic model - swat - on a micro agricultural basin of the rolling Pampa

    Directory of Open Access Journals (Sweden)

    Felipe Behrends Kraemer

    2011-07-01

    Full Text Available El modelado hidrológico es a menudo el primer paso en el desarrollo de sistemas de decisión espacial para identificaráreas vulnerables a la contaminación por nutrientes, pesticidas así como también a contaminantes biológicos. En este sentido el SWAT (Soil and Water Assesment Tool fue desarrollado para predecir impactos de las prácticas de manejo de las tierras en las aguas, sedimentos y agroquímicos en cuencas hidrográficas con diferentes suelos, usos y prácticas en largos períodos de tiempo. Aunque el mismo está siendo aplicado en todo el mundo, todavía no esta difundido su uso en la Argentina, no encontrándose al momento reportes al respecto. Este modelo se utilizó en una microcuenca agrícola de la Pampa Ondulada (Argentina y fue calibrado y validado utilizando los valores de escurrimientos medidos in situ. Se encontraron buenas eficiencias a escala diaria (R²: 0,55; R² ENS: 0,52 y pobres a escala mensual (R²: 0,34; R² ENS: 0,04. En la calibración, los escurrimientos fueron sobreestimados en un 31,8% y 32,6% para la escala mensual y diaria respectivamente, mientras que en la validación se sobreestimó un 42,5% para los valores mensuales y un 41,2% para los diarios. La aplicación del SWAT en esta microcuenca agrícola resultó auspiciosa y conduce a la inclusión de dicho modelo en futuros trabajos.A hydrological model is often the first step for the development of spatial decision systems in order to identify vulnerable areas to the pollution by nutrients, pesticides as well as biological contaminants. The SWAT model was developed to predict the impact of land management on water, agrochemicals and sediments in hydrographical basins with different soils, land uses and practices for long time periods. This model is being used all over the world but it has not been applied in Argentina until present. The SWAT model was used in an agricultural microbasin in the Rolling Pampa (Argentina and was calibrated and validated

  9. The Soil and Water Assessment Tool (SWAT) Ecohydrological Model Circa 2015: Global Application Trends, Insights and Issues

    Science.gov (United States)

    Gassman, P. W.; Arnold, J. G.; Srinivasan, R.

    2015-12-01

    The Soil and Water Assessment Tool (SWAT) is one of the most widely used watershed-scale water quality models in the world. Over 2,000 peer-reviewed SWAT-related journal articles have been published and hundreds of other studies have been published in conference proceedings and other formats. The use of SWAT was initially concentrated in North America and Europe but has also expanded dramatically in other countries and regions during the past decade including Brazil, China, India, Iran, South Korea, Southeast Asia and eastern Africa. The SWAT model has proven to be a very flexible tool for investigating a broad range of hydrologic and water quality problems at different watershed scales and environmental conditions, and has proven very adaptable for applications requiring improved hydrologic and other enhanced simulation needs. We investigate here the various technological, networking, and other factors that have supported the expanded use of SWAT, and also highlight current worldwide simulation trends and possible impediments to future increased usage of the model. Examples of technological advances include easy access to web-based documentation, user-support groups, and SWAT literature, a variety of Geographic Information System (GIS) interface tools, pre- and post-processing calibration software and other software, and an open source code which has served as a model development catalyst for multiple user groups. Extensive networking regarding the use of SWAT has further occurred via internet-based user support groups, model training workshops, regional working groups, regional and international conferences, and targeted development workshops. We further highlight several important model development trends that have emerged during the past decade including improved hydrologic, cropping system, best management practice (BMP) and pollutant transport simulation methods. In addition, several current SWAT weaknesses will be addressed and key development needs will be

  10. How to: understanding SWAT model uncertainty relative to measured results

    Science.gov (United States)

    Watershed models are being relied upon to contribute to most policy-making decisions of watershed management, and the demand for an accurate accounting of complete model uncertainty is rising. Generalized likelihood uncertainty estimation (GLUE) is a widely used method for quantifying uncertainty i...

  11. Value of using remotely sensed evapotranspiration for SWAT model calibration

    Science.gov (United States)

    Hydrologic models are useful management tools for assessing water resources solutions and estimating the potential impact of climate variation scenarios. A comprehensive understanding of the water budget components and especially the evapotranspiration (ET) is critical and often overlooked for adeq...

  12. The Impacts of Different Meteorology Data Sets on Nitrogen Fate and Transport in the SWAT Watershed Model

    Science.gov (United States)

    In this study, we investigated how different meteorology data sets impacts nitrogen fate and transport responses in the Soil and Water Assessment Tool (SWAT) model. We used two meteorology data sets: National Climatic Data Center (observed) and Mesoscale Model 5/Weather Research ...

  13. Remote sensing estimation of evapotranspiration for SWAT Model Calibration

    Science.gov (United States)

    Hydrological models are used to assess many water resource problems from water quantity to water quality issues. The accurate assessment of the water budget, primarily the influence of precipitation and evapotranspiration (ET), is a critical first-step evaluation, which is often overlooked in hydro...

  14. Spatial multiobjective optimization of agricultural conservation practices using a SWAT model and an evolutionary algorithm.

    Science.gov (United States)

    Rabotyagov, Sergey; Campbell, Todd; Valcu, Adriana; Gassman, Philip; Jha, Manoj; Schilling, Keith; Wolter, Calvin; Kling, Catherine

    2012-12-09

    Finding the cost-efficient (i.e., lowest-cost) ways of targeting conservation practice investments for the achievement of specific water quality goals across the landscape is of primary importance in watershed management. Traditional economics methods of finding the lowest-cost solution in the watershed context (e.g.,(5,12,20)) assume that off-site impacts can be accurately described as a proportion of on-site pollution generated. Such approaches are unlikely to be representative of the actual pollution process in a watershed, where the impacts of polluting sources are often determined by complex biophysical processes. The use of modern physically-based, spatially distributed hydrologic simulation models allows for a greater degree of realism in terms of process representation but requires a development of a simulation-optimization framework where the model becomes an integral part of optimization. Evolutionary algorithms appear to be a particularly useful optimization tool, able to deal with the combinatorial nature of a watershed simulation-optimization problem and allowing the use of the full water quality model. Evolutionary algorithms treat a particular spatial allocation of conservation practices in a watershed as a candidate solution and utilize sets (populations) of candidate solutions iteratively applying stochastic operators of selection, recombination, and mutation to find improvements with respect to the optimization objectives. The optimization objectives in this case are to minimize nonpoint-source pollution in the watershed, simultaneously minimizing the cost of conservation practices. A recent and expanding set of research is attempting to use similar methods and integrates water quality models with broadly defined evolutionary optimization methods(3,4,9,10,13-15,17-19,22,23,25). In this application, we demonstrate a program which follows Rabotyagov et al.'s approach and integrates a modern and commonly used SWAT water quality model(7) with a

  15. Assessment of the SWAT model to simulate a watershed with limited available data in the Pampas region, Argentina.

    Science.gov (United States)

    Romagnoli, Martín; Portapila, Margarita; Rigalli, Alfredo; Maydana, Gisela; Burgués, Martín; García, Carlos M

    2017-10-15

    Argentina has been among the world leaders in the production and export of agricultural products since the 1990s. The Carcarañá River Lower Basin (CRLB), a cropland of the Pampas region supplied by extensive rainfall, is located in an area with few streamgauging and other hydrologic/water-quality stations. Therefore, limited hydrologic data are available resulting in limited water-resources assessment. This work explores the application of Soil and Water Assessment Tool (SWAT) model to the CRLB in the Santa Fe province of the Pampas region. The analysis of field and remote-sensing data characterizing hydrology, water quality, soil types, land use/land cover, management practices, and crop yield, guarantee a comprehensive SWAT modeling approach. A combined manual and automated calibration and validation process incorporating sensitivity and uncertainty analysis is performed using information concerning interior watershed processes. Eleven N/P fertilizer rates are selected to simulate the impact of N fertilizer on crop yield, plant uptake, as well as runoff and leaching losses. Different indices (partial factor productivity, agronomic efficiency, apparent crop recovery efficiency of applied nutrient, internal utilization efficiency, and physiological efficiency) are considered to assess nitrogen-use efficiency. The overall quality of the fit is satisfactory considering the input data limitations. This work provides, for the first time in Argentina, a reliable tool to simulate yield response to soil quality and water availability capable to meet defined environmental targets to support decision making on planning public policies and private activities on the Pampas region. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Assessment of Riparian Buffer Impacts Within the Little River Watershed in Georgia USA with the SWAT Model

    Science.gov (United States)

    Computer based hydrologic and water quality models have proven to be useful tools for examining alternative management scenarios and their impact on the environment. This examination can be an important component of watershed-scale evaluations. The Soil and Water Assessment Tool (SWAT), is a water...

  17. Modeling Fate and Transport of Fecal Coliform Bacteria Using SWAT 2005 (Case Study: Jajrood River Watershed, Iran)

    Science.gov (United States)

    Maghrebi, M.; Tajrishy, M.

    2010-12-01

    Jajrood River watershed is one of the main drinking water resources of the capital city of Tehran, Iran. In addition it has been available as many recreational usages especially in the warm months. As a result of being located near one of the crowded cities of the world, a variety of microbial pollutions is commonly perceived in the Jajrood River. Among them, there are strong concerns about fecal coliform bacteria concentration. This article aimed to model fate and transport of fecal coliform bacteria in Jajrood River watershed using Soil and Water Assessment Tool (SWAT) model version 2005. Potential pollutant sources in the study area were detected and quantified for modeling purposes. In spite of being lack of knowledge about bacteria die-off rate in small river bodies, as well as in other watershed-based forms, fecal coliform bacteria die-off rates were estimated using both laboratory and field data investigations with some simplifications. The SWAT model was calibrated over an extended time period (1997-2002) for this watershed. The river flow calibrated using SUFI-2 software and resulted in a very good outputs (R2=0.82, E=0.81). Furthermore SWAT model was validated over January 2003 to September 2005 in the study area and has resulted in good outputs (R2=0.61, E=0.57). This research illustrates SWAT 2005 capability to model fecal coliform bacteria in a populated watershed, and deals with most of watershed microbial pollution sources that are usually observed in developing countries. Fecal coliform concentration simulation results were mostly in the same order in comparison with real data. However, Differences were judged to be related to lack of input data. In this article different aspects of SWAT capabilities for modeling of fecal coliform bacteria concentration will be reviewed and it will present new insights in bacteria modeling procedures especially for mountainous, high populated and small sized watersheds.

  18. Assessment of NASA's Physiographic and Meteorological Datasets as Input to HSPF and SWAT Hydrological Models

    Science.gov (United States)

    Alacron, Vladimir J.; Nigro, Joseph D.; McAnally, William H.; OHara, Charles G.; Engman, Edwin Ted; Toll, David

    2011-01-01

    This paper documents the use of simulated Moderate Resolution Imaging Spectroradiometer land use/land cover (MODIS-LULC), NASA-LIS generated precipitation and evapo-transpiration (ET), and Shuttle Radar Topography Mission (SRTM) datasets (in conjunction with standard land use, topographical and meteorological datasets) as input to hydrological models routinely used by the watershed hydrology modeling community. The study is focused in coastal watersheds in the Mississippi Gulf Coast although one of the test cases focuses in an inland watershed located in northeastern State of Mississippi, USA. The decision support tools (DSTs) into which the NASA datasets were assimilated were the Soil Water & Assessment Tool (SWAT) and the Hydrological Simulation Program FORTRAN (HSPF). These DSTs are endorsed by several US government agencies (EPA, FEMA, USGS) for water resources management strategies. These models use physiographic and meteorological data extensively. Precipitation gages and USGS gage stations in the region were used to calibrate several HSPF and SWAT model applications. Land use and topographical datasets were swapped to assess model output sensitivities. NASA-LIS meteorological data were introduced in the calibrated model applications for simulation of watershed hydrology for a time period in which no weather data were available (1997-2006). The performance of the NASA datasets in the context of hydrological modeling was assessed through comparison of measured and model-simulated hydrographs. Overall, NASA datasets were as useful as standard land use, topographical , and meteorological datasets. Moreover, NASA datasets were used for performing analyses that the standard datasets could not made possible, e.g., introduction of land use dynamics into hydrological simulations

  19. Hydrologic and atrazine simulation of the Cedar Creek Watershed using the SWAT model.

    Science.gov (United States)

    Larose, M; Heathman, G C; Norton, L D; Engel, B

    2007-01-01

    One of the major factors contributing to surface water contamination in agricultural areas is the use of pesticides. The Soil and Water Assessment Tool (SWAT) is a hydrologic model capable of simulating the fate and transport of pesticides in an agricultural watershed. The SWAT model was used in this study to estimate stream flow and atrazine (2-chloro-4-(ethylamino)-6-(isopropylamino)-s-triazine) losses to surface water in the Cedar Creek Watershed (CCW) within the St. Joseph River Basin in northeastern Indiana. Model calibration and validation periods consisted of five and two year periods, respectively. The National Agricultural Statistics Survey (NASS) 2001 land cover classification and the Soil Survey Geographic (SSURGO) database were used as model input data layers. Data from the St. Joseph River Watershed Initiative and the Soil and Water Conservation Districts of Allen, Dekalb, and Noble counties were used to represent agricultural practices in the watershed which included the type of crops grown, tillage practices, fertilizer, and pesticide application rates. Model results were evaluated based on efficiency coefficient values, standard statistical measures, and visual inspection of the measured and simulated hydrographs. The Nash and Sutcliffe model efficiency coefficients (E(NS)) for monthly and daily stream flow calibration and validation ranged from 0.51 to 0.66. The E(NS) values for atrazine calibration and validation ranged from 0.43 to 0.59. All E(NS) values were within the range of acceptable model performance standards. The results of this study indicate that the model is an effective tool in capturing the dynamics of stream flow and atrazine concentrations on a large-scale agricultural watershed in the midwestern USA.

  20. Effects of soil data resolution on SWAT model stream flow and water quality predictions.

    Science.gov (United States)

    Geza, Mengistu; McCray, John E

    2008-08-01

    The prediction accuracy of agricultural nonpoint source pollution models such as Soil and Water Assessment Tool (SWAT) depends on how well model input spatial parameters describe the characteristics of the watershed. The objective of this study was to assess the effects of different soil data resolutions on stream flow, sediment and nutrient predictions when used as input for SWAT. SWAT model predictions were compared for the two US Department of Agriculture soil databases with different resolution, namely the State Soil Geographic database (STATSGO) and the Soil Survey Geographic database (SSURGO). Same number of sub-basins was used in the watershed delineation. However, the number of HRUs generated when STATSGO and SSURGO soil data were used is 261 and 1301, respectively. SSURGO, with the highest spatial resolution, has 51 unique soil types in the watershed distributed in 1301 HRUs, while STATSGO has only three distributed in 261 HRUS. As a result of low resolution STATSGO assigns a single classification to areas that may have different soil types if SSURGO were used. SSURGO included Hydrologic Response Units (HRUs) with soil types that were generalized to one soil group in STATSGO. The difference in the number and size of HRUs also has an effect on sediment yield parameters (slope and slope length). Thus, as a result of the discrepancies in soil type and size of HRUs stream flow predicted was higher when SSURGO was used compared to STATSGO. SSURGO predicted less stream loading than STATSGO in terms of sediment and sediment-attached nutrients components, and vice versa for dissolved nutrients. When compared to mean daily measured flow, STATSGO performed better relative to SSURGO before calibration. SSURGO provided better results after calibration as evaluated by R(2) value (0.74 compared to 0.61 for STATSGO) and the Nash-Sutcliffe coefficient of Efficiency (NSE) values (0.70 and 0.61 for SSURGO and STATSGO, respectively) although both are in the same satisfactory

  1. Interpretation of Landscape Scale SWAT Model Outputs in the Western Lake Erie Basin: Potential Implications for Conservation Decision-Making

    Science.gov (United States)

    Johnson, M. V. V.; Behrman, K. D.; Atwood, J. D.; White, M. J.; Norfleet, M. L.

    2017-12-01

    There is substantial interest in understanding how conservation practices and agricultural management impact water quality, particularly phosphorus dynamics, in the Western Lake Erie Basin (WLEB). In 2016, the US and Canada accepted total phosphorus (TP) load targets recommended by the Great Lakes Water Quality Agreement Annex 4 Objectives and Targets Task Team; these were 6,000 MTA delivered to Lake Erie and 3,660 MTA delivered to WLEB. Outstanding challenges include development of metrics to determine achievement of these goals, establishment of sufficient monitoring capacity to assess progress, and identification of appropriate conservation practices to achieve the most cost-effective results. Process-based modeling can help inform decisions to address these challenges more quickly than can system observation. As part of the NRCS-led Conservation Effects Assessment Project (CEAP), the Soil Water Assessment Tool (SWAT) was used to predict impacts of conservation practice adoption reported by farmers on TP loss and load delivery dynamics in WLEB. SWAT results suggest that once the conservation practices in place in 2003-06 and 2012 are fully functional, TP loads delivered to WLEB will average 3,175 MTA and 3,084 MTA, respectively. In other words, SWAT predicts that currently adopted practices are sufficient to meet Annex 4 TP load targets. Yet, WLEB gauging stations show Annex 4 goals are unmet. There are several reasons the model predictions and current monitoring efforts are not in agreement: 1. SWAT assumes full functionality of simulated conservation practices; 2. SWAT does not simulate changing management over time, nor impacts of past management on legacy loads; 3. SWAT assumes WLEB hydrological system equilibrium under simulated management. The SWAT model runs used to construct the scenarios that informed the Annex 4 targets were similarly constrained by model assumptions. It takes time for a system to achieve equilibrium when management changes and it

  2. Developing Land Use Land Cover Maps for the Lower Mekong Basin to Aid SWAT Hydrologic Modeling

    Science.gov (United States)

    Spruce, J.; Bolten, J. D.; Srinivasan, R.

    2017-12-01

    This presentation discusses research to develop Land Use Land Cover (LULC) maps for the Lower Mekong Basin (LMB). Funded by a NASA ROSES Disasters grant, the main objective was to produce updated LULC maps to aid the Mekong River Commission's (MRC's) Soil and Water Assessment Tool (SWAT) hydrologic model. In producing needed LULC maps, temporally processed MODIS monthly NDVI data for 2010 were used as the primary data source for classifying regionally prominent forest and agricultural types. The MODIS NDVI data was derived from processing MOD09 and MYD09 8-day reflectance data with the Time Series Product Tool, a custom software package. Circa 2010 Landsat multispectral data from the dry season were processed into top of atmosphere reflectance mosaics and then classified to derive certain locally common LULC types, such as urban areas and industrial forest plantations. Unsupervised ISODATA clustering was used to derive most LULC classifications. GIS techniques were used to merge MODIS and Landsat classifications into final LULC maps for Sub-Basins (SBs) 1-8 of the LMB. The final LULC maps were produced at 250-meter resolution and delivered to the MRC for use in SWAT modeling for the LMB. A map accuracy assessment was performed for the SB 7 LULC map with 14 classes. This assessment was performed by comparing random locations for sampled LULC types to geospatial reference data such as Landsat RGBs, MODIS NDVI phenologic profiles, high resolution satellite data from Google Map/Earth, and other reference data from the MRC (e.g., crop calendars). LULC accuracy assessment results for SB 7 indicated an overall agreement to reference data of 81% at full scheme specificity. However, by grouping 3 deciduous forest classes into 1 class, the overall agreement improved to 87%. The project enabled updated LULC maps, plus more specific rice types were classified compared to the previous LULC maps. The LULC maps from this project should improve the use of SWAT for modeling

  3. Impacts of Irrigation Practices on Groundwater Recharge in Mississippi Delta Using coupled SWAT-MODFLOW Model

    Science.gov (United States)

    Gao, F.; Feng, G.; Han, M.; Jenkins, J.; Ouyang, Y.

    2017-12-01

    The Lower Mississippi River alluvial plain (refers to as MS Delta), located in the northwest state of Mississippi, is one of the most productive agricultural region in the U.S. The primary crops grown in this region are soybean, corn, cotton, and rice. Approximately 80% water from the alluvial aquifer in MS Delta are withdrawn for irrigation, which makes it the most used aquifer in the State. As a result, groundwater level has declined > 6 m since 1970, which threaten the sustainability of irrigated agriculture in this region. The objectives of this study were to: 1) couple the SWAT and MODFLOW then calibrate and validate the incorporated model outputs for stream flow, groundwater level and evapotranspiration (ET) in MS Delta; 2) simulate the groundwater recharge as affected by a) conventional irrigation scheme, b) no irrigation scheme, c) ET based and soil moisture based full irrigation schedules using all groundwater, and d) ET and soil moisture based full irrigation schedule using different percentages of surface and ground water. Results indicated that the coupled model performed well during the calibration and validation for daily stream flow at three USGS gauge stations. (R2=0.7; Nash-Sutcliffe efficiency (NSE) varied from 0.6 to 0.7; Root Mean Square Error (RMSE) ranged from 20 to 27 m3/s). The values of determination coefficient R2 for groundwater level were 0.95 for calibration and 0.88 for validation, their NSE values were 0.99 and 0.93, respectively. The values of RMSE for groundwater level during the calibration and validation period were 0.51 and 0.59 m. The values of R2, NSE and RMSE between SWAT-MODFLOW simulated actual evapotranspiration (ET) and remote sensing evapotranspiration (ET) were 0.52, 0.51 and 28.1 mm. The simulated total average monthly groundwater recharge had lower values of 19 mm/month in the crop season than 30 mm/month in the crop off-growing season. The SWAT-MODFLOW can be a useful tool for not only simulating the recharge in MS

  4. Evaluating Impacts of climate and land use changes on streamflow using SWAT and land use models based CESM1-CAM5 Climate scenarios

    Science.gov (United States)

    Lin, Tzu Ping; Lin, Yu Pin; Lien, Wan Yu

    2015-04-01

    Climate change projects have various levels of impacts on hydrological cycles around the world. The impact of climate change and uncertainty of climate projections from general circulation models (GCMs) from the Coupled Model Intercomparison Project (CMIP5) which has been just be released in Taiwan, 2014. Since the streamflow run into ocean directly due to the steep terrain and the rainfall difference between wet and dry seasons is apparent; as a result, the allocation water resource reasonable is very challenge in Taiwan, particularly under climate change. The purpose of this study was to evaluate the impacts of climate and land use changes on a small watershed in Taiwan. The AR5 General Circulation Models(GCM) output data was adopted in this study and was downscaled from the monthly to the daily weather data as the input data of hydrological model such as Soil and Water Assessment Tool (SWAT) model in this study. The spatially explicit land uses change model, the Conservation of Land Use and its Effects at Small regional extent (CLUE-s), was applied to simulate land use scenarios in 2020-2039. Combined climate and land use change scenarios were adopted as input data of the hydrological model, the SWAT model, to estimate the future streamflows. With the increasing precipitation, increasing urban area and decreasing agricultural and grass land, the annual streamflow in the most of twenty-three subbasins were also increased. Besides, due to the increasing rainfall in wet season and decreasing rainfall in dry season, the difference of streamflow between wet season and dry season are also increased. This result indicates a more stringent challenge on the water resource management in future. Therefore, impacts on water resource caused by climate change and land use change should be considered in water resource planning for the Datuan river watershed. Keywords: SWAT, GCM, CLUE-s, streamflow, climate change, land use change

  5. A Comparison of SWAT and ANN Models for Daily Runoff Simulation in Different Climatic Zones of Peninsular Spain

    OpenAIRE

    Patricia Jimeno-Sáez; Javier Senent-Aparicio; Julio Pérez-Sánchez; David Pulido-Velazquez

    2018-01-01

    Streamflow data are of prime importance to water-resources planning and management, and the accuracy of their estimation is very important for decision making. The Soil and Water Assessment Tool (SWAT) and Artificial Neural Network (ANN) models have been evaluated and compared to find a method to improve streamflow estimation. For a more complete evaluation, the accuracy and ability of these streamflow estimation models was also established separately based on their performance during differe...

  6. [Coupling SWAT and CE-QUAL-W2 models to simulate water quantity and quality in Shanmei Reservoir watershed].

    Science.gov (United States)

    Liu, Mei-Bing; Chen, Dong-Ping; Chen, Xing-Wei; Chen, Ying

    2013-12-01

    A coupled watershed-reservoir modeling approach consisting of a watershed distributed model (SWAT) and a two-dimensional laterally averaged model (CE-QUAL-W2) was adopted for simulating the impact of non-point source pollution from upland watershed on water quality of Shanmei Reservoir. Using the daily serial output from Shanmei Reservoir watershed by SWAT as the input to Shanmei Reservoir by CE-QUAL-W2, the coupled modeling was calibrated for runoff and outputs of sediment and pollutant at watershed scale and for elevation, temperature, nitrate, ammonium and total nitrogen in Shanmei Reservoir. The results indicated that the simulated values agreed fairly well with the observed data, although the calculation precision of downstream model would be affected by the accumulative errors generated from the simulation of upland model. The SWAT and CE-QUAL-W2 coupled modeling could be used to assess the hydrodynamic and water quality process in complex watershed comprised of upland watershed and downstream reservoir, and might further provide scientific basis for positioning key pollution source area and controlling the reservoir eutrophication.

  7. Stream Flow Simulation of a Snow-Fed Mountainous Basin Using the SWAT Model

    Science.gov (United States)

    Shukla, S.; Kansal, M. L.; Jain, S. K.

    2017-12-01

    Hydrological budget of the Satluj River (a major tributary of Indus river system) in Western Himalaya, is dominated by monsoonal rainfall and snowmelt during the non-monsoon months. The river watershed experiences extensive snowfall in the winters and snowmelt runoff substantially contributes to the streamflow of the river in the spring and summer months. In order to understand the hydrologic response of Satluj basin, hydrological modeling study is carried out using a semi distributed hydrological model Soil and Water Assessment Tool (SWAT), for the period of thirty years (1985-2014). The basic intent of this study is to derive the parameters required for runoff modeling using the geospatial database. The Sequential Uncertainty Fitting (SUFI-2) algorithm is used to calibrate and validate the model and incorporate uncertainties in the analysis. The results are validated with the observed daily streamflow data at Rampur, in terms of Nash-Sutcliffe Coefficient (NSC), R2 and Root Mean Square Error (RMSE). Further, the snowmelt-runoff mechanism is modelled by relating the temperature changes to the elevation band in the basin. The northern part of the basin and the south part of the basin on the high elevation zones have the coldest maximum temperatures that is about 7°C. It is found that the average contribution of snow and glacier runoff in the annual flow of the Satluj River at Rampur is about 66% and remaining 34% is from rainfall.

  8. Land use change impacts on discharge analysis using SWAT model at Ciherang Pondok DAM catchment area

    Science.gov (United States)

    Utamahadi, M. A.; Pandjaitan, N. H.; Rau, M. I.

    2018-05-01

    The prompt increase of population influenced the requirement for new regions to fulfill people’s primary needs. Its increased land use change and caused many impacts on the environment, including watersheds as well. Ciherang Pondok DAM catchment area is part of Cisadane watershed and was selected as the research area. This research aimed to analyse the water supply and water discharge change caused by the Urban Planning (RTRW) in 2020. The analysis was conducted using soil and water assessment tools (SWAT) model. Stages of this research were catchment area delineation, HRU identification, calibration and validation of models, and prediction of discharge and water demand. The result showed that RTRW of 2020 increased the maximum discharge of 1.6 m3/s and decreased the minimum discharge of 0.01 m3/s, hence the maximum and minimum discharge ratio increased 0.26% from 2016. Output discharge in 2020 at Ciherang Pondok Dam Catchment Area was classified as well, with discharge of 6.72 – 126.2 m3/s, and could fulfil water demand. For the best result, it is better to use climate data from weather stations inside the study area and it is required an improvement in data archiving system.

  9. Free internet datasets for streamflow modelling using SWAT in the Johor river basin, Malaysia

    Science.gov (United States)

    Tan, M. L.

    2014-02-01

    Streamflow modelling is a mathematical computational approach that represents terrestrial hydrology cycle digitally and is used for water resources assessment. However, such modelling endeavours require a large amount of data. Generally, governmental departments produce and maintain these data sets which make it difficult to obtain this data due to bureaucratic constraints. In some countries, the availability and quality of geospatial and climate datasets remain a critical issue due to many factors such as lacking of ground station, expertise, technology, financial support and war time. To overcome this problem, this research used public domain datasets from the Internet as "input" to a streamflow model. The intention is simulate daily and monthly streamflow of the Johor River Basin in Malaysia. The model used is the Soil and Water Assessment Tool (SWAT). As input free data including a digital elevation model (DEM), land use information, soil and climate data were used. The model was validated by in-situ streamflow information obtained from Rantau Panjang station for the year 2006. The coefficient of determination and Nash-Sutcliffe efficiency were 0.35/0.02 for daily simulated streamflow and 0.92/0.21 for monthly simulated streamflow, respectively. The results show that free data can provide a better simulation at a monthly scale compared to a daily basis in a tropical region. A sensitivity analysis and calibration procedure should be conducted in order to maximize the "goodness-of-fit" between simulated and observed streamflow. The application of Internet datasets promises an acceptable performance of streamflow modelling. This research demonstrates that public domain data is suitable for streamflow modelling in a tropical river basin within acceptable accuracy.

  10. Free internet datasets for streamflow modelling using SWAT in the Johor river basin, Malaysia

    International Nuclear Information System (INIS)

    Tan, M L

    2014-01-01

    Streamflow modelling is a mathematical computational approach that represents terrestrial hydrology cycle digitally and is used for water resources assessment. However, such modelling endeavours require a large amount of data. Generally, governmental departments produce and maintain these data sets which make it difficult to obtain this data due to bureaucratic constraints. In some countries, the availability and quality of geospatial and climate datasets remain a critical issue due to many factors such as lacking of ground station, expertise, technology, financial support and war time. To overcome this problem, this research used public domain datasets from the Internet as ''input'' to a streamflow model. The intention is simulate daily and monthly streamflow of the Johor River Basin in Malaysia. The model used is the Soil and Water Assessment Tool (SWAT). As input free data including a digital elevation model (DEM), land use information, soil and climate data were used. The model was validated by in-situ streamflow information obtained from Rantau Panjang station for the year 2006. The coefficient of determination and Nash-Sutcliffe efficiency were 0.35/0.02 for daily simulated streamflow and 0.92/0.21 for monthly simulated streamflow, respectively. The results show that free data can provide a better simulation at a monthly scale compared to a daily basis in a tropical region. A sensitivity analysis and calibration procedure should be conducted in order to maximize the ''goodness-of-fit'' between simulated and observed streamflow. The application of Internet datasets promises an acceptable performance of streamflow modelling. This research demonstrates that public domain data is suitable for streamflow modelling in a tropical river basin within acceptable accuracy

  11. Modeling pesticide diuron loading from the San Joaquin watershed into the Sacramento-San Joaquin Delta using SWAT.

    Science.gov (United States)

    Chen, Huajin; Luo, Yuzhou; Potter, Christopher; Moran, Patrick J; Grieneisen, Michael L; Zhang, Minghua

    2017-09-15

    Quantifying pesticide loading into the Sacramento-San Joaquin Delta of northern California is critical for water quality management in the region, and potentially useful for biological weed control planning. In this study, the Soil and Water Assessment Tool (SWAT) was applied to model streamflow, sediment, and pesticide diuron loading in the San Joaquin watershed, a major contributing area to the elevated pesticide levels in the downstream Delta. The Sequential Uncertainty Fitting version 2 (SUFI-2) algorithm was employed to perform calibration and uncertainty analysis. A combination of performance measures (PMs) and standardized performance evaluation criteria (PEC) was applied to evaluate model performance, while prediction uncertainty was quantified by 95% prediction uncertainty band (95PPU). Results showed that streamflow simulation was at least "satisfactory" at most stations, with more than 50% of the observed data bracketed by the 95PPU. Sediment simulation was rated as at least "satisfactory" based on two PMs, and diuron simulation was judged as "good" by all PMs. The 95PPU of sediment and diuron bracketed about 40% and 30% of the observed data, respectively. Significant correlations were observed between the diuron loads, and precipitation, streamflow, and the current and antecedent pesticide use. Results also showed that the majority (>70%) of agricultural diuron was transported during winter months, when direct exposure of biocontrol agents to diuron runoff is limited. However, exposure in the dry season could be a concern because diuron is relatively persistent in aquatic system. This study not only provides valuable information for the development of biological weed control plan in the Delta, but also serves as a foundation for the continued research on calibration, evaluation, and uncertainty analysis of spatially distributed, physically based hydrologic models. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Analysis of the spatial variation in the parameters of the SWAT model with application in Flanders, Northern Belgium

    Directory of Open Access Journals (Sweden)

    G. Heuvelmans

    2004-01-01

    Full Text Available Operational applications of a hydrological model often require the prediction of stream flow in (future time periods without stream flow observations or in ungauged catchments. Data for a case-specific optimisation of model parameters are not available for such applications, so parameters have to be derived from other catchments or time periods. It has been demonstrated that for applications of the SWAT in Northern Belgium, temporal transfers of the parameters have less influence than spatial transfers on the performance of the model. This study examines the spatial variation in parameter optima in more detail. The aim was to delineate zones wherein model parameters can be transferred without a significant loss of model performance. SWAT was calibrated for 25 catchments that are part of eight larger sub-basins of the Scheldt river basin. Two approaches are discussed for grouping these units in zones with a uniform set of parameters: a single parameter approach considering each parameter separately and a parameter set approach evaluating the parameterisation as a whole. For every catchment, the SWAT model was run with the local parameter optima, with the average parameter values for the entire study region (Flanders, with the zones delineated with the single parameter approach and with the zones obtained by the parameter set approach. Comparison of the model performances of these four parameterisation strategies indicates that both the single parameter and the parameter set zones lead to stream flow predictions that are more accurate than if the entire study region were treated as one single zone. On the other hand, the use of zonal average parameter values results in a considerably worse model fit compared to local parameter optima. Clustering of parameter sets gives a more accurate result than the single parameter approach and is, therefore, the preferred technique for use in the parameterisation of ungauged sub-catchments as part of the

  13. Water quantity and quality optimization modeling of dams operation based on SWAT in Wenyu River Catchment, China.

    Science.gov (United States)

    Zhang, Yongyong; Xia, Jun; Chen, Junfeng; Zhang, Minghua

    2011-02-01

    Water quantity and quality joint operation is a new mode in the present dams' operation research. It has become a hot topic in governmental efforts toward integrated basin improvement. This paper coupled a water quantity and quality joint operation model (QCmode) and genetic algorithm with Soil and Water Assessment Tool (SWAT). Together, these tools were used to explore a reasonable operation of dams and floodgates at the basin scale. Wenyu River Catchment, a key area in Beijing, was selected as the case study. Results showed that the coupled water quantity and quality model of Wenyu River Catchment more realistically simulates the process of water quantity and quality control by dams and floodgates. This integrated model provides the foundation for research of water quantity and quality optimization on dam operation in Wenyu River Catchment. The results of this modeling also suggest that current water quality of Wenyu River will improve following the implementation of the optimized operation of the main dams and floodgates. By pollution control and water quantity and quality joint operation of dams and floodgates, water quality of Wenyu river will change significantly, and the available water resources will increase by 134%, 32%, 17%, and 82% at the downstream sites of Sha River Reservoir, Lutong Floodgate, Xinpu Floodgate, and Weigou Floodgate, respectively. The water quantity and quality joint operation of dams will play an active role in improving water quality and water use efficiency in Wenyu River Basin. The research will provide the technical support for water pollution control and ecological restoration in Wenyu River Catchment and could be applied to other basins with large number of dams. Its application to the Wenyu River Catchment has a great significance for the sustainable economic development of Beijing City.

  14. Uncertainty of SWAT model at different DEM resolutions in a large mountainous watershed.

    Science.gov (United States)

    Zhang, Peipei; Liu, Ruimin; Bao, Yimeng; Wang, Jiawei; Yu, Wenwen; Shen, Zhenyao

    2014-04-15

    The objective of this study was to enhance understanding of the sensitivity of the SWAT model to the resolutions of Digital Elevation Models (DEMs) based on the analysis of multiple evaluation indicators. The Xiangxi River, a large tributary of Three Gorges Reservoir in China, was selected as the study area. A range of 17 DEM spatial resolutions, from 30 to 1000 m, was examined, and the annual and monthly model outputs based on each resolution were compared. The following results were obtained: (i) sediment yield was greatly affected by DEM resolution; (ii) the prediction of dissolved oxygen load was significantly affected by DEM resolutions coarser than 500 m; (iii) Total Nitrogen (TN) load was not greatly affected by the DEM resolution; (iv) Nitrate Nitrogen (NO₃-N) and Total Phosphorus (TP) loads were slightly affected by the DEM resolution; and (v) flow and Ammonia Nitrogen (NH₄-N) load were essentially unaffected by the DEM resolution. The flow and dissolved oxygen load decreased more significantly in the dry season than in the wet and normal seasons. Excluding flow and dissolved oxygen, the uncertainties of the other Hydrology/Non-point Source (H/NPS) pollution indicators were greater in the wet season than in the dry and normal seasons. Considering the temporal distribution uncertainties, the optimal DEM resolutions for flow was 30-200 m, for sediment and TP was 30-100 m, for dissolved oxygen and NO₃-N was 30-300 m, for NH₄-N was 30 to 70 m and for TN was 30-150 m. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Modelling land use change across elevation gradients in district Swat, Pakistan

    NARCIS (Netherlands)

    Qasim, M.; Termansen, M.; Hubacek, K.; Fleskens, L.

    2013-01-01

    District Swat is part of the high mountain Hindu-Kush Himalayan region of Pakistan. Documentation and analysis of land use change in this region is challenging due to very disparate accounts of the state of forest resources and limited accessible data. Such analysis is, however, important due to

  16. The modified SWAT model for predicting fecal coliform in the Wachusett Reservoir Watershed, USA

    Science.gov (United States)

    Fecal contamination has been an issue for water quality because fecal coliform bacteria are used as an indicator organism to detect pathogens in water. In order to assess fecal contamination in the Wachusett Reservoir Watershed in Massachusetts, USA, the Soil and Water Assessment Tool (SWAT), a comm...

  17. Modeling pesticide loadings from the San Joaquin watershed into the Sacramento-San Joaquin Delta using SWAT

    Science.gov (United States)

    Chen, H.; Zhang, M.

    2016-12-01

    The Sacramento-San Joaquin Delta is an ecologically rich, hydrologically complex area that serves as the hub of California's water supply. However, pesticides have been routinely detected in the Delta waterways, with concentrations exceeding the benchmark for the protection of aquatic life. Pesticide loadings into the Delta are partially attributed to the San Joaquin watershed, a highly productive agricultural watershed located upstream. Therefore, this study aims to simulate pesticide loadings to the Delta by applying the Soil and Water Assessment Tool (SWAT) model to the San Joaquin watershed, under the support of the USDA-ARS Delta Area-Wide Pest Management Program. Pesticide use patterns in the San Joaquin watershed were characterized by combining the California Pesticide Use Reporting (PUR) database and GIS analysis. Sensitivity/uncertainty analyses and multi-site calibration were performed in the simulation of stream flow, sediment, and pesticide loads along the San Joaquin River. Model performance was evaluated using a combination of graphic and quantitative measures. Preliminary results indicated that stream flow was satisfactorily simulated along the San Joaquin River and the major eastern tributaries, whereas stream flow was less accurately simulated in the western tributaries, which are ephemeral small streams that peak during winter storm events and are mainly fed by irrigation return flow during the growing season. The most sensitive parameters to stream flow were CN2, SOL_AWC, HRU_SLP, SLSUBBSN, SLSOIL, GWQMN and GW_REVAP. Regionalization of parameters is important as the sensitivity of parameters vary significantly spatially. In terms of evaluation metric, NSE tended to overrate model performance when compared to PBIAS. Anticipated results will include (1) pesticide use pattern analysis, (2) calibration and validation of stream flow, sediment, and pesticide loads, and (3) characterization of spatial patterns and temporal trends of pesticide yield.

  18. Application of SELECT and SWAT models to simulate source load, fate, and transport of fecal bacteria in watersheds.

    Science.gov (United States)

    Ranatunga, T.

    2017-12-01

    Modeling of fate and transport of fecal bacteria in a watershed is a processed based approach that considers releases from manure, point sources, and septic systems. Overland transport with water and sediments, infiltration into soils, transport in the vadose zone and groundwater, die-off and growth processes, and in-stream transport are considered as the other major processes in bacteria simulation. This presentation will discuss a simulation of fecal indicator bacteria source loading and in-stream conditions of a non-tidal watershed (Cedar Bayou Watershed) in South Central Texas using two models; Spatially Explicit Load Enrichment Calculation Tool (SELECT) and Soil and Water Assessment Tool (SWAT). Furthermore, it will discuss a probable approach of bacteria source load reduction in order to meet the water quality standards in the streams. The selected watershed is listed as having levels of fecal indicator bacteria that posed a risk for contact recreation and wading by the Texas Commission of Environmental Quality (TCEQ). The SELECT modeling approach was used in estimating the bacteria source loading from land categories. Major bacteria sources considered were, failing septic systems, discharges from wastewater treatment facilities, excreta from livestock (Cattle, Horses, Sheep and Goat), excreta from Wildlife (Feral Hogs, and Deer), Pet waste (mainly from Dogs), and runoff from urban surfaces. The estimated source loads from SELECT model were input to the SWAT model, and simulate the bacteria transport through the land and in-stream. The calibrated SWAT model was then used to estimate the indicator bacteria in-stream concentrations for future years based on regional land use, population and household forecast (up to 2040). Based on the reductions required to meet the water quality standards in-stream, the corresponding required source load reductions were estimated.

  19. SWAT4.0 - The integrated burnup code system driving continuous energy Monte Carlo codes MVP, MCNP and deterministic calculation code SRAC

    International Nuclear Information System (INIS)

    Kashima, Takao; Suyama, Kenya; Takada, Tomoyuki

    2015-03-01

    There have been two versions of SWAT depending on details of its development history: the revised SWAT that uses the deterministic calculation code SRAC as a neutron transportation solver, and the SWAT3.1 that uses the continuous energy Monte Carlo code MVP or MCNP5 for the same purpose. It takes several hours, however, to execute one calculation by the continuous energy Monte Carlo code even on the super computer of the Japan Atomic Energy Agency. Moreover, two-dimensional burnup calculation is not practical using the revised SWAT because it has problems on production of effective cross section data and applying them to arbitrary fuel geometry when a calculation model has multiple burnup zones. Therefore, SWAT4.0 has been developed by adding, to SWAT3.1, a function to utilize the deterministic code SARC2006, which has shorter calculation time, as an outer module of neutron transportation solver for burnup calculation. SWAT4.0 has been enabled to execute two-dimensional burnup calculation by providing an input data template of SRAC2006 to SWAT4.0 input data, and updating atomic number densities of burnup zones in each burnup step. This report describes outline, input data instruction, and examples of calculations of SWAT4.0. (author)

  20. A comparison of SWAT, HSPF and SHETRAN/GOPC for modelling phosphorus export from three catchments in Ireland.

    Science.gov (United States)

    Nasr, Ahmed; Bruen, Michael; Jordan, Philip; Moles, Richard; Kiely, Gerard; Byrne, Paul

    2007-03-01

    Recent extensive water quality surveys in Ireland revealed that diffuse phosphorus (P) pollution originating from agricultural land and transported by runoff and subsurface flows is the primary cause of the deterioration of surface water quality. P transport from land to water can be described by mathematical models that vary in modelling approach, complexity and scale (plot, field and catchment). Here, three mathematical models (soil water and analysis tools (SWAT), hydrological simulation program-FORTRAN (HSPF) and système hydrologique Européen TRANsport (SHETRAN)/grid oriented phosphorus component (GOPC)) of diffuse P pollution have been tested in three Irish catchments to explore their suitability in Irish conditions for future use in implementing the European Water Framework Directive. After calibrating the models, their daily flows and total phosphorus (TP) exports are compared and assessed. The HSPF model was the best at simulating the mean daily discharge while SWAT gave the best calibration results for daily TP loads. Annual TP exports for the three models and for two empirical models were compared with measured data. No single model is consistently better in estimating the annual TP export for all three catchments.

  1. A multi basin SWAT model analysis of runoff and sedimentation in the Blue Nile, Ethiopia

    Directory of Open Access Journals (Sweden)

    Z. M. Easton

    2010-10-01

    Full Text Available A multi basin analysis of runoff and erosion in the Blue Nile Basin, Ethiopia was conducted to elucidate sources of runoff and sediment. Erosion is arguably the most critical problem in the Blue Nile Basin, as it limits agricultural productivity in Ethiopia, degrades benthos in the Nile, and results in sedimentation of dams in downstream countries. A modified version of the Soil and Water Assessment Tool (SWAT model was developed to predict runoff and sediment losses from the Ethiopian Blue Nile Basin. The model simulates saturation excess runoff from the landscape using a simple daily water balance coupled to a topographic wetness index in ways that are consistent with observed runoff processes in the basin. The spatial distribution of landscape erosion is thus simulated more correctly. The model was parameterized in a nested design for flow at eight and sediment at three locations in the basin. Subbasins ranged in size from 1.3 to 174 000 km2, and interestingly, the partitioning of runoff and infiltrating flow could be predicted by topographic information. Model predictions showed reasonable accuracy (Nash Sutcliffe Efficiencies ranged from 0.53–0.92 with measured data across all sites except Kessie, where the water budget could not be closed; however, the timing of flow was well captured. Runoff losses increased with rainfall during the monsoonal season and were greatest from areas with shallow soils and large contributing areas. Analysis of model results indicate that upland landscape erosion dominated sediment delivery to the main stem of the Blue Nile in the early part of the growing season when tillage occurs and before the soil was wetted up and plant cover was established. Once plant cover was established in mid August landscape erosion was negligible and sediment export was dominated by channel processes and re-suspension of landscape sediment deposited early in the growing season. These results imply that targeting small

  2. Pesticide transport to tile-drained fields in SWAT model – macropore flow and sediment

    DEFF Research Database (Denmark)

    Lu, Shenglan; Trolle, Dennis; Blicher-Mathiesen, Gitte

    2015-01-01

    Tool (SWAT) to simulate transport of both mobile (e.g. Bentazon) and strongly sorbed (e.g. Diuron) pesticides in tile drains. Macropore flow is initiated when soil water content exceeds a threshold and rainfall intensity exceeds infiltration capacity. The amount of macropore flow is calculated...... to macropore sediment transport. Simulated tile drain discharge, sediment and pesticide loads are calibrated against data from intensively monitored tile-drained fields and streams in Denmark....

  3. Rainfall estimation in SWAT: An alternative method to simulate orographic precipitation

    Science.gov (United States)

    Galván, L.; Olías, M.; Izquierdo, T.; Cerón, J. C.; Fernández de Villarán, R.

    2014-02-01

    The input of water from precipitation is one of the most important aspects of a hydrologic model because it controls the basin's water budget. The model should reproduce the amount and distribution of rainfall in the basin, spatially and temporally. SWAT (Soil and Water Assessment Tool) is one of the most widely used hydrologic models. In this paper the rainfall estimation in SWAT is revised, focusing on the treatment of orographic precipitation. SWAT was applied to the Odiel river basin (SW Spain), with a surface of 2300 km2. Results show that SWAT does not reflect reallisticaly the spatial distribution of rainfall in the basin. In relation to orographic precipitation, SWAT estimates the daily precipitation in elevation bands by adding a constant amount to the recorded precipitation in the rain gauge, which depends on the increase in precipitation with altitude and the difference between the mean elevation of each band and the elevation of the recording gauge. This does not reflect rainfall in the subbasin because the increase in precipitation with altitude actually it is not constant, but depends on the amount of rainfall. An alternative methodology to represent the temporal distribution of orographic precipitation is proposed. After simulation, the deviation of runoff volume using the SWAT elevation bands was appreciably higher than that obtained with the proposed methodology.

  4. Assessment of land-use change on streamflow using GIS, remote sensing and a physically-based model, SWAT

    Directory of Open Access Journals (Sweden)

    J. Y. G. Dos Santos

    2014-09-01

    Full Text Available This study aims to assess the impact of the land-use changes between the periods 1967−1974 and 1997−2008 on the streamflow of Tapacurá catchment (northeastern Brazil using the Soil and Water Assessment Tool (SWAT model. The results show that the most sensitive parameters were the baseflow, Manning factor, time of concentration and soil evaporation compensation factor, which affect the catchment hydrology. The model calibration and validation were performed on a monthly basis, and the streamflow simulation showed a good level of accuracy for both periods. The obtained R2 and Nash-Sutcliffe Efficiency values for each period were respectively 0.82 and 0.81 for 1967−1974, and 0.93 and 0.92 for the period 1997−2008. The evaluation of the SWAT model response to the land cover has shown that the mean monthly flow, during the rainy seasons for 1967−1974, decreased when compared to 1997−2008.

  5. Comment on “Modeling Miscanthus in the Soil and Water Assessment Tool (SWAT) to Simulate Its Water Quality Effects As a Bioenergy Crop”

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xuesong; Izaurralde, Roberto C.; Arnold, J. G.; Sammons, N. B.; Manowitz, David H.; Thomson, Allison M.; Williams, J.R.

    2011-07-01

    In this paper, the authors comment on several mistakes made in a journal paper "Modeling Miscanthus in the Soil and Water Assessment Tool (SWAT) to Simulate Its Water Quality Effects As a Bioenergy Crop" published on Environmental Scienece & Technology, based on field measurements from Great Lakes Bioenergy Research Center, Carbon Sequestration in Terrestrial Ecosystems, and published literature. Our comment has led to the development of another version of SWAT to include better process based description of radiation use efficiency and root-shoot growth.

  6. A SWAT model validation of nested-scale contemporaneous stream flow, suspended sediment and nutrients from a multiple-land-use watershed of the central USA.

    Science.gov (United States)

    Zeiger, Sean J; Hubbart, Jason A

    2016-12-01

    There is an ongoing need to validate the accuracy of predictive model simulated pollutant yields, particularly from multiple-land-use (i.e. forested, agricultural, and urban) watersheds. However, there are seldom sufficient observed data sets available that supply requisite spatial and temporal resolution and coupled multi-parameter constituents for rigorous model performance assessment. Four years of hydroclimate and water quality data were used to validate SWAT model estimates of monthly stream flow, suspended sediment, total phosphorus, nitrate, nitrite, ammonium, and total inorganic nitrogen from 5 nested-scale gauging sites located in a multiple-land-use watershed of the central USA. The uncalibrated SWAT model satisfactorily simulated monthly stream flow with Nash-Sutcliffe efficiency (NSE) values ranging from 0.50 near the headwaters, to 0.75 near the watershed outlet. However, the uncalibrated model did not accurately simulate monthly sediment, total phosphorus, nitrate, nitrite, ammonium, and total inorganic nitrogen with NSE valuesSWAT model to multiple gauging sites within the watershed improved estimates of monthly stream flow (NSE=0.83), sediment (NSE=0.78), total phosphorus (NSE=0.81), nitrate (NSE=0.90), and total inorganic nitrogen (NSE=0.86). However, NSE values were model performance decreased for sediment, nitrate, and total inorganic nitrogen during the validation period with NSE valuesSWAT model to multiple gauging sites and provide guidance to SWAT model (or similar models) users wishing to improve model performance at multiple scales. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Streamflow in the upper Mississippi river basin as simulated by SWAT driven by 20{sup th} century contemporary results of global climate models and NARCCAP regional climate models

    Energy Technology Data Exchange (ETDEWEB)

    Takle, Eugene S.; Jha, Manoj; Lu, Er; Arritt, Raymond W.; Gutowski, William J. [Iowa State Univ. Ames, IA (United States)

    2010-06-15

    We use Soil and Water Assessment Tool (SWAT) when driven by observations and results of climate models to evaluate hydrological quantities, including streamflow, in the Upper Mississippi River Basin (UMRB) for 1981-2003 in comparison to observed streamflow. Daily meteorological conditions used as input to SWAT are taken from (1) observations at weather stations in the basin, (2) daily meteorological conditions simulated by a collection of regional climate models (RCMs) driven by reanalysis boundary conditions, and (3) daily meteorological conditions simulated by a collection of global climate models (GCMs). Regional models used are those whose data are archived by the North American Regional Climate Change Assessment Program (NARCCAP). Results show that regional models correctly simulate the seasonal cycle of precipitation, temperature, and streamflow within the basin. Regional models also capture interannual extremes represented by the flood of 1993 and the dry conditions of 2000. The ensemble means of both the GCM-driven and RCM-driven simulations by SWAT capture both the timing and amplitude of the seasonal cycle of streamflow with neither demonstrating significant superiority at the basin level. (orig.)

  8. SWAT Model Application to Assess the Impact of Intensive Corn‐farming on Runoff, Sediments and Phosphorous loss from an Agricultural Watershed in Wisconsin

    Science.gov (United States)

    The potential future increase in corn-based biofuel may be expected to have a negative impact on water quality in streams and lakes of the Midwestern US due to increased agricultural chemicals usage. This study used the SWAT model to assess the impact of continuous-corn farming o...

  9. Modeling the Impacts of Spatial Heterogeneity in the Castor Watershed on Runoff, Sediment, and Phosphorus Loss Using SWAT: I. Impacts of Spatial Variability of Soil Properties.

    Science.gov (United States)

    Boluwade, Alaba; Madramootoo, Chandra

    2013-01-01

    Spatial accuracy of hydrologic modeling inputs influences the output from hydrologic models. A pertinent question is to know the optimal level of soil sampling or how many soil samples are needed for model input, in order to improve model predictions. In this study, measured soil properties were clustered into five different configurations as inputs to the Soil and Water Assessment Tool (SWAT) simulation of the Castor River watershed (11-km 2 area) in southern Quebec, Canada. SWAT is a process-based model that predicts the impacts of climate and land use management on water yield, sediment, and nutrient fluxes. SWAT requires geographical information system inputs such as the digital elevation model as well as soil and land use maps. Mean values of soil properties are used in soil polygons (soil series); thus, the spatial variability of these properties is neglected. The primary objective of this study was to quantify the impacts of spatial variability of soil properties on the prediction of runoff, sediment, and total phosphorus using SWAT. The spatial clustering of the measured soil properties was undertaken using the regionalized with dynamically constrained agglomerative clustering and partitioning method. Measured soil data were clustered into 5, 10, 15, 20, and 24 heterogeneous regions. Soil data from the Castor watershed which have been used in previous studies was also set up and termed "Reference". Overall, there was no significant difference in runoff simulation across the five configurations including the reference. This may be attributable to SWAT's use of the soil conservation service curve number method in flow simulation. Therefore having high spatial resolution inputs for soil data may not necessarily improve predictions when they are used in hydrologic modeling.

  10. [Impact of changes in land use and climate on the runoff in Liuxihe Watershed based on SWAT model].

    Science.gov (United States)

    Yuan, Yu-zhi; Zhang, Zheng-dong; Meng, Jin-hua

    2015-04-01

    SWAT model, an extensively used distributed hydrological model, was used to quantitatively analyze the influences of changes in land use and climate on the runoff at watershed scale. Liuxihe Watershed' s SWAT model was established and three scenarios were set. The calibration and validation at three hydrological stations of Wenquan, Taipingchang and Nangang showed that the three factors of Wenquan station just only reached the standard in validated period, and the other two stations had relative error (RE) 0.8 and Nash-Sutcliffe efficiency valve (Ens) > 0.75, suggesting that SWAT model was appropriate for simulating runoff response to land use change and climate variability in Liuxihe watershed. According to the integrated scenario simulation, the annual runoff increased by 11.23 m3 x s(-1) from 2001 to 2010 compared with the baseline period from 1991 to 2000, among which, the land use change caused an annual runoff reduction of 0.62 m3 x s(-1), whereas climate variability caused an annual runoff increase of 11.85 m3 x s(-1). Apparently, the impact of climate variability was stronger than that of land use change. On the other hand, the scenario simulation of extreme land use showed that compared with the land use in 2000, the annual runoff of the farmland scenario and the grassland scenario increased by 2.7% and 0.5% respectively, while that of the forest land scenario were reduced by 0.7%, which suggested that forest land had an ability of diversion closure. Furthermore, the scenario simulation of climatic variability indicated that the change of river runoff correlated positively with precipitation change (increase of 11.6% in annual runoff with increase of 10% in annual precipitation) , but negatively with air temperature change (reduction of 0.8% in annual runoff with increase of 1 degrees C in annual mean air temperature), which showed that the impact of precipitation variability was stronger than that of air temperature change. Therefore, in face of climate

  11. Modeling Agricultural Watersheds with the Soil and Water Assessment Tool (SWAT): Calibration and Validation with a Novel Procedure for Spatially Explicit HRUs.

    Science.gov (United States)

    Teshager, Awoke Dagnew; Gassman, Philip W; Secchi, Silvia; Schoof, Justin T; Misgna, Girmaye

    2016-04-01

    Applications of the Soil and Water Assessment Tool (SWAT) model typically involve delineation of a watershed into subwatersheds/subbasins that are then further subdivided into hydrologic response units (HRUs) which are homogeneous areas of aggregated soil, landuse, and slope and are the smallest modeling units used within the model. In a given standard SWAT application, multiple potential HRUs (farm fields) in a subbasin are usually aggregated into a single HRU feature. In other words, the standard version of the model combines multiple potential HRUs (farm fields) with the same landuse/landcover, soil, and slope, but located at different places of a subbasin (spatially non-unique), and considers them as one HRU. In this study, ArcGIS pre-processing procedures were developed to spatially define a one-to-one match between farm fields and HRUs (spatially unique HRUs) within a subbasin prior to SWAT simulations to facilitate input processing, input/output mapping, and further analysis at the individual farm field level. Model input data such as landuse/landcover (LULC), soil, crop rotation, and other management data were processed through these HRUs. The SWAT model was then calibrated/validated for Raccoon River watershed in Iowa for 2002-2010 and Big Creek River watershed in Illinois for 2000-2003. SWAT was able to replicate annual, monthly, and daily streamflow, as well as sediment, nitrate and mineral phosphorous within recommended accuracy in most cases. The one-to-one match between farm fields and HRUs created and used in this study is a first step in performing LULC change, climate change impact, and other analyses in a more spatially explicit manner.

  12. SWAT (Student Weekend Arborist Team): A Model for Land Grant Institutions and Cooperative Extension Systems to Conduct Street Tree Inventories

    Science.gov (United States)

    Cowett, F.D.; Bassuk, N.L.

    2012-01-01

    SWAT (Student Weekend Arborist Team) is a program affiliated with Cornell University and Extension founded to conduct street tree inventories in New York State communities with 10,000 residents or fewer, a group of communities underserved in community forestry planning. Between 2002 and 2010, SWAT conducted 40 inventories, and data from these…

  13. Evaluating Uncertainty of Runoff Simulation using SWAT model of the Feilaixia Watershed in China Based on the GLUE Method

    Science.gov (United States)

    Chen, X.; Huang, G.

    2017-12-01

    In recent years, distributed hydrological models have been widely used in storm water management, water resources protection and so on. Therefore, how to evaluate the uncertainty of the model reasonably and efficiently becomes a hot topic today. In this paper, the soil and water assessment tool (SWAT) model is constructed for the study area of China's Feilaixia watershed, and the uncertainty of the runoff simulation is analyzed by GLUE method deeply. Taking the initial parameter range of GLUE method as the research core, the influence of different initial parameter ranges on model uncertainty is studied. In this paper, two sets of parameter ranges are chosen as the object of study, the first one (range 1) is recommended by SWAT-CUP and the second one (range 2) is calibrated by SUFI-2. The results showed that under the same number of simulations (10,000 times), the overall uncertainty obtained by the range 2 is less than the range 1. Specifically, the "behavioral" parameter sets for the range 2 is 10000 and for the range 1 is 4448. In the calibration and the validation, the ratio of P-factor to R-factor for range 1 is 1.387 and 1.391, and for range 2 is 1.405 and 1.462 respectively. In addition, the simulation result of range 2 is better with the NS and R2 slightly higher than range 1. Therefore, it can be concluded that using the parameter range calibrated by SUFI-2 as the initial parameter range for the GLUE is a way to effectively capture and evaluate the simulation uncertainty.

  14. Quantifying the Contribution of On-Site Wastewater Treatment Systems to Stream Discharge Using the SWAT Model.

    Science.gov (United States)

    Oliver, C W; Radcliffe, D E; Risse, L M; Habteselassie, M; Mukundan, R; Jeong, J; Hoghooghi, N

    2014-03-01

    In the southeastern United States, on-site wastewater treatment systems (OWTSs) are widely used for domestic wastewater treatment. The degree to which OWTSs represent consumptive water use has been questioned in Georgia. The goal of this study was to estimate the effect of OWTSs on streamflow in a gauged watershed in Gwinnett County, Georgia using the Soil and Water Assessment Tool (SWAT) watershed-scale model, which includes a new OWTS algorithm. Streamflow was modeled with and without the presence of OWTSs. The model was calibrated using data from 1 Jan. 2003 to 31 Dec. 2006 and validated from 1 Jan. 2007 to 31 Dec. 2010 using the auto-calibration tool SWAT-CUP 4. The daily and monthly streamflow Nash-Sutcliffe coefficients were 0.49 and 0.71, respectively, for the calibration period and 0.37 and 0.68, respectively, for the validation period, indicating a satisfactory fit. Analysis of water balance output variables between simulations showed a 3.1% increase in total water yield at the watershed scale and a 5.9% increase at the subbasin scale for a high-density OWTS area. The percent change in water yield between simulations was the greatest in dry years, implying that the influence of OWTSs on the water yield is greatest under drought conditions. Mean OWTS water use was approximately 5.7% consumptive, contrary to common assumptions by water planning agencies in Georgia. Results from this study may be used by OWTS users and by watershed planners to understand the influence of OWTSs on water quantity within watersheds in this region. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  15. Hydrological simulation in a basin of typical tropical climate and soil using the SWAT model part I: Calibration and validation tests

    Directory of Open Access Journals (Sweden)

    Donizete dos R. Pereira

    2016-09-01

    New hydrological insights: The SWAT model was qualified for simulating the Pomba River sub-basin in the sites where rainfall representation was reasonable to good. The model can be used in the simulation of maximum, average and minimum annual daily streamflow based on the paired t-test, contributing with the water resources management of region, although the model still needs to be improved, mainly in the representativeness of rainfall, to give better estimates of extreme values.

  16. A continental-scale hydrology and water quality model for Europe: Calibration and uncertainty of a high-resolution large-scale SWAT model

    Science.gov (United States)

    Abbaspour, K. C.; Rouholahnejad, E.; Vaghefi, S.; Srinivasan, R.; Yang, H.; Kløve, B.

    2015-05-01

    A combination of driving forces are increasing pressure on local, national, and regional water supplies needed for irrigation, energy production, industrial uses, domestic purposes, and the environment. In many parts of Europe groundwater quantity, and in particular quality, have come under sever degradation and water levels have decreased resulting in negative environmental impacts. Rapid improvements in the economy of the eastern European block of countries and uncertainties with regard to freshwater availability create challenges for water managers. At the same time, climate change adds a new level of uncertainty with regard to freshwater supplies. In this research we build and calibrate an integrated hydrological model of Europe using the Soil and Water Assessment Tool (SWAT) program. Different components of water resources are simulated and crop yield and water quality are considered at the Hydrological Response Unit (HRU) level. The water resources are quantified at subbasin level with monthly time intervals. Leaching of nitrate into groundwater is also simulated at a finer spatial level (HRU). The use of large-scale, high-resolution water resources models enables consistent and comprehensive examination of integrated system behavior through physically-based, data-driven simulation. In this article we discuss issues with data availability, calibration of large-scale distributed models, and outline procedures for model calibration and uncertainty analysis. The calibrated model and results provide information support to the European Water Framework Directive and lay the basis for further assessment of the impact of climate change on water availability and quality. The approach and methods developed are general and can be applied to any large region around the world.

  17. PATHOGEN TRANSPORT AND FATE MODELING IN THE UPPER SALEM RIVER WATERSHED USING SWAT MODEL - PEER-REVIEWED JOURNAL ARTICLE

    Science.gov (United States)

    Simulation of the fate and transport of pathogen contamination was conducted with SWAT for the Upper Salem River Watershed, located in Salem County, New Jersey. This watershed is 37 km2 and land uses are predominantly agricultural. The watershed drains to a 32 km str...

  18. Hydrologic Response Unit Routing in SWAT to Simulate Effects of Vegetated Filter Strip for South-Korean Conditions Based on VFSMOD

    Directory of Open Access Journals (Sweden)

    Kyoung Jae Lim

    2011-08-01

    Full Text Available The Soil and Water Assessment Tool (SWAT model has been used worldwide for many hydrologic and Non-Point Source (NPS Pollution analyses on a watershed scale. However, it has many limitations in simulating the Vegetative Filter Strip (VFS because it considers only ‘filter strip width’ when the model estimates sediment trapping efficiency and does not consider the routing of sediment with overland flow which is expected to maximize the sediment trapping efficiency from upper agricultural subwatersheds to lower spatially-explicit filter strips. Therefore, the SWAT overland flow option between landuse-subwatersheds with sediment routing capability was enhanced by modifying the SWAT watershed configuration and SWAT engine based on the numerical model VFSMOD applied to South-Korean conditions. The enhanced SWAT can simulate the VFS sediment trapping efficiency for South-Korean conditions in a manner similar to the desktop VFSMOD-w system. Due to this enhancement, SWAT is applicable to simulate the effects of overland flow from upper subwatersheds to reflect increased runoff volume at the lower subwatershed, which occurs in the field if no diversion channel is installed. In this study, the enhanced SWAT model was applied to small watersheds located at Jaun-ri in South-Korea to simulate a diversion channel and spatially-explicit VFS. Sediment can be reduced by 31%, 65%, and 68%, with a diversion channel, the VFS, and the VFS with diversion channel, respectively. The enhanced SWAT should be used in estimating site-specific effects on sediment reduction with diversion channels and VFS, instead of the currently available SWAT, which does not simulate sediment routing in overland flow and does not consider other sensitive factors affecting sediment reduction with VFS.

  19. SWAT2: The improved SWAT code system by incorporating the continuous energy Monte Carlo code MVP

    International Nuclear Information System (INIS)

    Mochizuki, Hiroki; Suyama, Kenya; Okuno, Hiroshi

    2003-01-01

    SWAT is a code system, which performs the burnup calculation by the combination of the neutronics calculation code, SRAC95 and the one group burnup calculation code, ORIGEN2.1. The SWAT code system can deal with the cell geometry in SRAC95. However, a precise treatment of resonance absorptions by the SRAC95 code using the ultra-fine group cross section library is not directly applicable to two- or three-dimensional geometry models, because of restrictions in SRAC95. To overcome this problem, SWAT2 which newly introduced the continuous energy Monte Carlo code, MVP into SWAT was developed. Thereby, the burnup calculation by the continuous energy in any geometry became possible. Moreover, using the 147 group cross section library called SWAT library, the reactions which are not dealt with by SRAC95 and MVP can be treated. OECD/NEA burnup credit criticality safety benchmark problems Phase-IB (PWR, a single pin cell model) and Phase-IIIB (BWR, fuel assembly model) were calculated as a verification of SWAT2, and the results were compared with the average values of calculation results of burnup calculation code of each organization. Through two benchmark problems, it was confirmed that SWAT2 was applicable to the burnup calculation of the complicated geometry. (author)

  20. Comparative analyses of hydrological responses of two adjacent watersheds to climate variability and change using the SWAT model

    Science.gov (United States)

    Lee, Sangchul; Yeo, In-Young; Sadeghi, Ali M.; McCarty, Gregory W.; Hively, Wells; Lang, Megan W.; Sharifi, Amir

    2018-01-01

    Water quality problems in the Chesapeake Bay Watershed (CBW) are expected to be exacerbated by climate variability and change. However, climate impacts on agricultural lands and resultant nutrient loads into surface water resources are largely unknown. This study evaluated the impacts of climate variability and change on two adjacent watersheds in the Coastal Plain of the CBW, using the Soil and Water Assessment Tool (SWAT) model. We prepared six climate sensitivity scenarios to assess the individual impacts of variations in CO2concentration (590 and 850 ppm), precipitation increase (11 and 21 %), and temperature increase (2.9 and 5.0 °C), based on regional general circulation model (GCM) projections. Further, we considered the ensemble of five GCM projections (2085–2098) under the Representative Concentration Pathway (RCP) 8.5 scenario to evaluate simultaneous changes in CO2, precipitation, and temperature. Using SWAT model simulations from 2001 to 2014 as a baseline scenario, predicted hydrologic outputs (water and nitrate budgets) and crop growth were analyzed. Compared to the baseline scenario, a precipitation increase of 21 % and elevated CO2 concentration of 850 ppm significantly increased streamflow and nitrate loads by 50 and 52 %, respectively, while a temperature increase of 5.0 °C reduced streamflow and nitrate loads by 12 and 13 %, respectively. Crop biomass increased with elevated CO2 concentrations due to enhanced radiation- and water-use efficiency, while it decreased with precipitation and temperature increases. Over the GCM ensemble mean, annual streamflow and nitrate loads showed an increase of  ∼  70 % relative to the baseline scenario, due to elevated CO2 concentrations and precipitation increase. Different hydrological responses to climate change were observed from the two watersheds, due to contrasting land use and soil characteristics. The watershed with a larger percent of croplands demonstrated a greater

  1. Comparative analyses of hydrological responses of two adjacent watersheds to climate variability and change using the SWAT model

    Science.gov (United States)

    Lee, Sangchul; Yeo, In-Young; Sadeghi, Ali M.; McCarty, Gregory W.; Hively, Wells D.; Lang, Megan W.; Sharifi, Amir

    2018-01-01

    Water quality problems in the Chesapeake Bay Watershed (CBW) are expected to be exacerbated by climate variability and change. However, climate impacts on agricultural lands and resultant nutrient loads into surface water resources are largely unknown. This study evaluated the impacts of climate variability and change on two adjacent watersheds in the Coastal Plain of the CBW, using the Soil and Water Assessment Tool (SWAT) model. We prepared six climate sensitivity scenarios to assess the individual impacts of variations in CO2 concentration (590 and 850 ppm), precipitation increase (11 and 21 %), and temperature increase (2.9 and 5.0 °C), based on regional general circulation model (GCM) projections. Further, we considered the ensemble of five GCM projections (2085-2098) under the Representative Concentration Pathway (RCP) 8.5 scenario to evaluate simultaneous changes in CO2, precipitation, and temperature. Using SWAT model simulations from 2001 to 2014 as a baseline scenario, predicted hydrologic outputs (water and nitrate budgets) and crop growth were analyzed. Compared to the baseline scenario, a precipitation increase of 21 % and elevated CO2 concentration of 850 ppm significantly increased streamflow and nitrate loads by 50 and 52 %, respectively, while a temperature increase of 5.0 °C reduced streamflow and nitrate loads by 12 and 13 %, respectively. Crop biomass increased with elevated CO2 concentrations due to enhanced radiation- and water-use efficiency, while it decreased with precipitation and temperature increases. Over the GCM ensemble mean, annual streamflow and nitrate loads showed an increase of ˜ 70 % relative to the baseline scenario, due to elevated CO2 concentrations and precipitation increase. Different hydrological responses to climate change were observed from the two watersheds, due to contrasting land use and soil characteristics. The watershed with a larger percent of croplands demonstrated a greater increased rate of 5.2 kg N ha-1 in

  2. A new R-SWAT Decision Making Framework for the Efficient Allocation of Best Management Practices

    OpenAIRE

    UDIAS MOINELO ANGEL; MALAGO ANNA; REYNAUD ARNAUD; PASTORI MARCO; VIGIAK OLGA; BOURAOUI Faycal

    2015-01-01

    The work presents and illustrates the application of R-SWAT-DM, a new R framework designed for Decision Making (DM), related to the implementation of Best Management Practices (BMPs), for restoring and protecting the good ecological status of freshwater bodies. R-SWAT-DM combines the use of the SWAT watershed model, the spatial representation of BMPs and an economic component. The SWAT model served as the nonpoint source pollution estimator for current conditions (base line) as well as for sc...

  3. Evaluation of drought impact on groundwater recharge rate using SWAT and Hydrus models on an agricultural island in western Japan

    Directory of Open Access Journals (Sweden)

    G. Jin

    2015-06-01

    Full Text Available Clarifying the variations of groundwater recharge response to a changing non-stationary hydrological process is important for efficiently managing groundwater resources, particularly in regions with limited precipitation that face the risk of water shortage. However, the rate of aquifer recharge is difficult to evaluate in terms of large annual-variations and frequency of flood events. In our research, we attempt to simulate related groundwater recharge processes under variable climate conditions using the SWAT Model, and validate the groundwater recharge using the Hydrus Model. The results show that annual average groundwater recharge comprised approximately 33% of total precipitation, however, larger variation was found for groundwater recharge and surface runoff compared to evapotranspiration, which fluctuated with annual precipitation variations. The annual variation of groundwater resources is shown to be related to precipitation. In spatial variations, the upstream is the main surface water discharge area; the middle and downstream areas are the main groundwater recharge areas. Validation by the Hydrus Model shows that the estimated and simulated groundwater levels are consistent in our research area. The groundwater level shows a quick response to the groundwater recharge rate. The rainfall intensity had a great impact on the changes of the groundwater level. Consequently, it was estimated that large spatial and temporal variation of the groundwater recharge rate would be affected by precipitation uncertainty in future.

  4. Spatiotemporal impacts of LULC changes on hydrology from the perspective of runoff generation mechanism using SWAT model with evolving parameters

    Science.gov (United States)

    Li, Y.; Chang, J.; Luo, L.

    2017-12-01

    It is of great importance for water resources management to model the truly hydrological process under changing environment, especially under significant changes of underlying surfaces like the Wei River Bain (WRB) where the subsurface hydrology is highly influenced by human activities, and to systematically investigate the interactions among LULC change, streamflow variation and changes in runoff generation process. Therefore, we proposed the idea of evolving parameters in hydrological model (SWAT) to reflect the changes in physical environment with different LULC conditions. Then with these evolving parameters, the spatiotemporal impacts of LULC changes on streamflow were quantified, and qualitative analysis was conducted to further explore how LULC changes affect the streamflow from the perspective of runoff generation mechanism. Results indicate the following: 1) evolving parameter calibration is not only effective but necessary to ensure the validity of the model when dealing with significant changes in underlying surfaces due to human activities. 2) compared to the baseline period, the streamflow in wet seasons increased in the 1990s but decreased in the 2000s. While at yearly and dry seasonal scales, the streamflow decreased in both two decades; 3) the expansion of cropland is the major contributor to the reduction of surface water component, thus causing the decline in streamflow at yearly and dry seasonal scales. While compared to the 1990s, the expansions of woodland in the middle stream and grassland in the downstream are the main stressors that increased the soil water component, thus leading to the more decline of the streamflow in the 2000s.

  5. Hydrological modeling of the pipestone creek watershed using the Soil Water Assessment Tool (SWAT: Assessing impacts of wetland drainage on hydrology

    Directory of Open Access Journals (Sweden)

    Cesar Perez-Valdivia

    2017-12-01

    Full Text Available Study region: Prairie Pothole Region of North America. Study focus: The Prairie Pothole Region of North America has experienced extensive wetland drainage, potentially impacting peak flows and annual flow volumes. Some of this drainage has occurred in closed basins, possibly impacting lake water levels of these systems. In this study we investigated the potential impact of wetland drainage on peak flows and annual volumes in a 2242 km2 watershed located in southeastern Saskatchewan (Canada using the Soil Water Assessment Tool (SWAT model. New hydrological insights: The SWAT model, which had been calibrated and validated at daily and monthly time steps for the 1997–2009 period, was used to assess the impact of wetland drainage using three hypothetical scenarios that drained 15, 30, and 50% of the non-contributing drainage area. Results of these simulations suggested that drainage increased spring peak flows by about 50, 79 and 113%, respectively while annual flow volumes increased by about 43, 68, and 98% in each scenario. Years that were wetter than normal presented increased peak flows and annual flow volumes below the average of the simulated period. Alternatively, summer peak flows presented smaller increases in terms of percentages during the simulated period. Keywords: Soil Water Assessment Tool (SWAT, Wetland drainage, Peak flow, Annual volume, Prairie Pothole Region

  6. The Assessment of Green Water Based on the SWAT Model: A Case Study in the Hai River Basin, China

    Directory of Open Access Journals (Sweden)

    Kui Zhu

    2018-06-01

    Full Text Available Green water accounts for two-thirds of precipitation, and the proportion could be even higher in dry years. Conflicts between water supply and demand have gradually become severe in the Hai River Basin (HRB due to the socio-economic development. Thus, the exploitation and the utilization of green water have attracted increasing attention. By gathering the related hydrological, meteorological, and geographic data, the spatiotemporal distribution of green water in HRB and the impacts of land use types on green water are analyzed based on the SWAT (Soil and Water Assessment Tool model in this study. Furthermore, three new indices are proposed for evaluation, including the maximum possible storage of green water (MSGW, the consumed green water (CGW, and the utilizable green water (UGW. The results show that (1 the MSGW is relatively low in plain areas and its spatial distribution is significantly associated with the soil type; (2 according to the evaluation results of CGW and UGW in HRB, a further improvement of utilization efficiency of green water could be achieved; (3 in general, the utilization efficiency of precipitation in farmlands is higher than other land use types, which means that the planting of appropriate plants could be helpful to enhance the utilization efficiency of green water. Our results summarize the spatiotemporal distribution of green water resource and provide a reference for water resources management in other water-short agricultural areas.

  7. Assessing the impacts of sustainable agricultural practices for water quality improvements in the Vouga catchment (Portugal) using the SWAT model.

    Science.gov (United States)

    Rocha, João; Roebeling, Peter; Rial-Rivas, María Ermitas

    2015-12-01

    The extensive use of fertilizers has become one of the most challenging environmental issues in agricultural catchment areas. In order to reduce the negative impacts from agricultural activities and to accomplish the objectives of the European Water Framework Directive we must consider the implementation of sustainable agricultural practices. In this study, we assess sustainable agricultural practices based on reductions in N-fertilizer application rates (from 100% to 0%) and N-application methods (single, split and slow-release) across key agricultural land use classes in the Vouga catchment, Portugal. The SWAT model was used to relate sustainable agricultural practices, agricultural yields and N-NO3 water pollution deliveries. Results show that crop yields as well as N-NO3 exportation rates decrease with reductions in N-application rates and single N-application methods lead to lower crop yields and higher N-NO3 exportation rates as compared to split and slow-release N-application methods. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Case Study: Effect of Climatic Characterization on River Discharge in an Alpine-Prealpine Catchment of the Spanish Pyrenees Using the SWAT Model

    Directory of Open Access Journals (Sweden)

    Leticia Palazón

    2016-10-01

    Full Text Available The new challenges in assessment of water resources demand new approaches and tools, such as the use of hydrologic models, which could serve to assist managers in the prediction, planning and management of catchment water supplies in view of increased demand of water for irrigation and climatic change. Good characterization of the spatial patterns of climate variables is of paramount importance in hydrological modelling. This is especially so when modelling mountain environments which are characterized by strong altitudinal climate gradients. However, very often there is a poor distribution of climatic stations in these areas, which in many cases, results in under representation of high altitude areas with respect to climatic data. This results in the poor performance of the models. In the present study, the Soil and Water Assessment Tool (SWAT model was applied to the Barasona reservoir catchment in the Central Spanish Pyrenees in order to assess the influence of different climatic characterizations in the monthly river discharges. Four simulations with different input data were assessed, using only the available climate data (A1; the former plus one synthetic dataset at a higher altitude (B1; and both plus the altitudinal climate gradient (A2 and B2. The model’s performance was evaluated against the river discharges for the representative periods of 2003–2005 and 1994–1996 by means of commonly used statistical measures. The best results were obtained using the altitudinal climate gradient alone (scenario A2. This study provided insight into the importance of taking into account the sources and the spatial distribution of weather data in modelling water resources in mountainous catchments.

  9. Application of the SWAT model to an AMD-affected river (Meca River, SW Spain). Estimation of transported pollutant load

    Science.gov (United States)

    Galván, L.; Olías, M.; Fernandez de Villarán, R.; Domingo Santos, J. M.; Nieto, J. M.; Sarmiento, A. M.; Cánovas, C. R.

    2009-10-01

    SummaryThe Meca River is highly contaminated by acid mine drainage coming from the Tharsis mining district, belonging to the Iberian Pyrite Belt. This river is regulated by the Sancho reservoir (58 hm 3), with a pH close to 4.2. In this work, the load transported by the Meca River to the Sancho reservoir has been assessed. Due to the lack of streamflow data, the hydrological behaviour of the Meca River basin has been simulated using the SWAT model. The model has been calibrated against registered daily inflows of the Sancho reservoir (1982-2000), excluding the hydrological years 2000/2001 and 2001/2002 that were kept for the validation. The results were satisfactory; the evaluation coefficients for monthly calibration were: r = 0.85 (Pearson's correlation coefficient), NSE = 0.83 (Nash-Sutcliffe coefficient) and DV = 1.08 (runoff volume deviation). The main uncertainty was the calibration during low water because of the poor accuracy in the measurement of the inputs to the reservoir in these conditions. Discharge and dissolved concentration relationships for different elements were obtained from hydrochemical samplings, which allowed us to estimate the element pollutant load transported to the reservoir: 418 ton/year of Al, 8024 ton/year of SO 4, 121 ton/year of Zn, etc. Based on these loads, concentrations in the reservoir were calculated for some elements. Apart from Mn and Sr, good adjustment between calculated and measured values was observed (±20% for Ca, Co, Li, Mg, Na, Ni, Zn and SO 4). Capsule: Hydrological model combined with water quality data show how pollution by AMD can generate huge loads of contaminants acidifying streams and reservoirs.

  10. Macrophyte growth module for the SWAT model – impact of climate change and management on stream ecology

    DEFF Research Database (Denmark)

    Lu, Shenglan; Trolle, Dennis; Erfurt, Jytte

    To access how multiple stressors affect the water quantity and quality and stream ecology at catchment scale under various management and climate change scenarios, we implemented macrophyte growth modules for the Soil and Water Assessment Tool version 2012 (SWAT). The macrophyte growth module...

  11. Analysing the Effects of Forest Cover and Irrigation Farm Dams on Streamflows of Water-Scarce Catchments in South Australia through the SWAT Model

    Directory of Open Access Journals (Sweden)

    Hong Hanh Nguyen

    2017-01-01

    Full Text Available To assist water resource managers with future land use planning efforts, the eco-hydrological model Soil and Water Assessment Tool (SWAT was applied to three catchments in South Australia that experience extreme low flow conditions. Particular land uses and management issues of interest included forest covers, known to affect water yields, and farm dams, known to intercept and change the hydrological dynamics in a catchment. The study achieved a satisfactory daily calibration when irrigation farm dams were incorporated in the model. For the catchment dominated by extreme low flows, a better daily simulation across a range of qualitative and quantitative metrics was gained using the base-flow static threshold optimization technique. Scenario analysis on effects of forest cover indicated an increase of surface flow and a reduction of base-flow when native eucalyptus lands were replaced by pastures and vice versa. A decreasing trend was observed for the overall water yield of catchments with more forest plantation due to the higher evapotranspiration (ET rate and the decline in surface flow. With regards to effects of irrigation farm dams, assessment on a daily time step suggested that a significant volume of water is stored in these systems with the water loss rate highest in June and July. On an annual basis, the model indicated that approximately 13.1% to 22.0% of water has been captured by farm dams for irrigation. However, the scenario analysis revealed that the purposes of use of farm dams rather than their volumetric capacities in the catchment determined the magnitude of effects on streamflows. Water extracted from farm dams for irrigation of orchards and vineyards are more likely to diminish streamflows than other land uses. Outputs from this study suggest that the water use restrictions from farm dams during recent drought periods were an effective tool to minimize impacts on streamflows.

  12. Hydrology and sediment yield calibration for the Barasona reservoir catchment (Spain) using SWAT

    Science.gov (United States)

    Palazón, Leticia; Navas, Ana

    2013-04-01

    Hydrological and soil erosion models, as Soil and Water Assessment Tool (SWAT), have become very useful tools and increasingly serve as vital components of integrated environmental assessments that provide information outside of direct field experiments and causal observation. The purpose of this study was to improve the calibration of SWAT model to use it in an alpine catchment as a simulator of processes related to water quality and soil erosion. SWAT is spatially semi-distributed, agro-hydrological model that operates on a daily time step (as a minimum) at basin scale. It is designed to predict the impact of management on water, sediment and agricultural chemical yields in ungaged catchments. SWAT provides physically based algorithms as an option to define many of the important components of the hydrologic cycle. The input requirements of the model are used to describe the climate, soil properties, topography, vegetation, and land management practices. SWAT analyzes small or large catchments by discretising into sub-basins, which are then further subdivided into hydrological response units (HRUs) with homogeneous land use, soil type and slope. SWAT model (SWAT2009) coupled with a GIS interface (ArcSWAT), was applied to the Barasona reservoir catchment located in the central Spanish Pyrenees. The 1509 km2 agro-forestry catchment presents a mountain type climate, an altitudinal range close to 3000 meters and a precipitation variation close to 1000 mm/km. The mountainous characteristics of the catchment, in addition to the scarcity of climate data in the region, require specific calibration for some processes. Snowfall and snowmelt are significant processes in the hydrologic regime of the area and were calibrated in a previous work. In this work some of the challenges of the catchment to model with SWAT which affected the hydrology and the sediment yield simulation were performed as improvement of the previous calibration. Two reservoirs, a karst system which

  13. Integrated Approach to Inform the New York City Water Supply System Coupling SAR Remote Sensing Observations and the SWAT Watershed Model

    Science.gov (United States)

    Tesser, D.; Hoang, L.; McDonald, K. C.

    2017-12-01

    Efforts to improve municipal water supply systems increasingly rely on an ability to elucidate variables that drive hydrologic dynamics within large watersheds. However, fundamental model variables such as precipitation, soil moisture, evapotranspiration, and soil freeze/thaw state remain difficult to measure empirically across large, heterogeneous watersheds. Satellite remote sensing presents a method to validate these spatially and temporally dynamic variables as well as better inform the watershed models that monitor the water supply for many of the planet's most populous urban centers. PALSAR 2 L-band, Sentinel 1 C-band, and SMAP L-band scenes covering the Cannonsville branch of the New York City (NYC) water supply watershed were obtained for the period of March 2015 - October 2017. The SAR data provides information on soil moisture, free/thaw state, seasonal surface inundation, and variable source areas within the study site. Integrating the remote sensing products with watershed model outputs and ground survey data improves the representation of related processes in the Soil and Water Assessment Tool (SWAT) utilized to monitor the NYC water supply. PALSAR 2 supports accurate mapping of the extent of variable source areas while Sentinel 1 presents a method to model the timing and magnitude of snowmelt runoff events. SMAP Active Radar soil moisture product directly validates SWAT outputs at the subbasin level. This blended approach verifies the distribution of soil wetness classes within the watershed that delineate Hydrologic Response Units (HRUs) in the modified SWAT-Hillslope. The research expands the ability to model the NYC water supply source beyond a subset of the watershed while also providing high resolution information across a larger spatial scale. The global availability of these remote sensing products provides a method to capture fundamental hydrology variables in regions where current modeling efforts and in situ data remain limited.

  14. Single-objective vs. multi-objective autocalibration in modelling total suspended solids and phosphorus in a small agricultural watershed with SWAT.

    Science.gov (United States)

    Rasolomanana, Santatriniaina Denise; Lessard, Paul; Vanrolleghem, Peter A

    2012-01-01

    To obtain greater precision in modelling small agricultural watersheds, a shorter simulation time step is beneficial. A daily time step better represents the dynamics of pollutants in the river and provides more realistic simulation results. However, with a daily evaluation performance, good fits are rarely obtained. With the Shuffled Complex Evolution (SCE) method embedded in the Soil and Water Assessment Tool (SWAT), two calibration approaches are available, single-objective or multi-objective optimization. The goal of the present study is to evaluate which approach can improve the daily performance with SWAT, in modelling flow (Q), total suspended solids (TSS) and total phosphorus (TP). The influence of weights assigned to the different variables included in the objective function has also been tested. The results showed that: (i) the model performance depends not only on the choice of calibration approach, but essentially on the influential parameters; (ii) the multi-objective calibration estimating at once all parameters related to all measured variables is the best approach to model Q, TSS and TP; (iii) changing weights does not improve model performance; and (iv) with a single-objective optimization, an excellent water quality modelling performance may hide a loss of performance of predicting flows and unbalanced internal model components.

  15. Algorithm Theory - SWAT 2006

    DEFF Research Database (Denmark)

    This book constitutes the refereed proceedings of the 10th Scandinavian Workshop on Algorithm Theory, SWAT 2006, held in Riga, Latvia, in July 2006. The 36 revised full papers presented together with 3 invited papers were carefully reviewed and selected from 154 submissions. The papers address all...

  16. Applied impulsive mathematical models

    CERN Document Server

    Stamova, Ivanka

    2016-01-01

    Using the theory of impulsive differential equations, this book focuses on mathematical models which reflect current research in biology, population dynamics, neural networks and economics. The authors provide the basic background from the fundamental theory and give a systematic exposition of recent results related to the qualitative analysis of impulsive mathematical models. Consisting of six chapters, the book presents many applicable techniques, making them available in a single source easily accessible to researchers interested in mathematical models and their applications. Serving as a valuable reference, this text is addressed to a wide audience of professionals, including mathematicians, applied researchers and practitioners.

  17. ROLE OF WATERSHED SUBDIVISION ON MODELING THE EFFECTIVENESS OF BEST MANAGEMENT PRACTICES WITH SWAT

    Science.gov (United States)

    Distributed parameter watershed models are often used for evaluating the effectiveness of various best management practices (BMPs). Streamflow, sediment, and nutrient yield predictions of a watershed model can be affected by spatial resolution as dictated by watershed subdivisio...

  18. Consideration of drainage ditches and sediment rating cure on SWAT model performance

    Science.gov (United States)

    Water quality models most often require a considerable amount of data to be properly configured and in some cases this requires additional procedural steps prior to model applications. We examined two different scenarios of such input issues in a small watershed using the Soil and Water Assessment ...

  19. Improving SWAT model prediction using an upgraded denitrification scheme and constrained auto calibration

    Science.gov (United States)

    The reliability of common calibration practices for process based water quality models has recently been questioned. A so-called “adequately calibrated model” may contain input errors not readily identifiable by model users, or may not realistically represent intra-watershed responses. These short...

  20. How to constrain multi-objective calibrations of the SWAT model using water balance components

    Science.gov (United States)

    Automated procedures are often used to provide adequate fits between hydrologic model estimates and observed data. While the models may provide good fits based upon numeric criteria, they may still not accurately represent the basic hydrologic characteristics of the represented watershed. Here we ...

  1. U.S. and Australian Mine Warfare Sonar Performance Assessment Using SWAT and Hodgson Models

    National Research Council Canada - National Science Library

    Dubsky, Barbra

    2000-01-01

    The purpose of this thesis was to investigate a shallow coastal region to compile a detailed environmental picture of its sediment composition and water characteristics and from this model MCM sonar...

  2. Improved simulation of river water and groundwater exchange in an alluvial plain using the SWAT model

    Science.gov (United States)

    Hydrological interaction between surface and subsurface water systems has a significant impact on water quality, ecosystems and biogeochemistry cycling of both systems. Distributed models have been developed to simulate this function, but they require detailed spatial inputs and extensive computati...

  3. Evaluating the SWAT model for a low-gradient forested watershed in coastal South Carolina

    Science.gov (United States)

    D.M. Amatya; M.K. Jha.

    2011-01-01

    Modeling the hydrology of low�]gradient forested watersheds on shallow, poorly drained soils of the coastal plain is a challenging task due to complexities in watershed delineation, microtopography, evapotranspiration, runoff generation processes and pathways including flooding and submergence caused by tropical storms, and complexity of vegetation species....

  4. Problems and Prospects of SWAT Model Application on an Arid/Semi-arid Watershed in Arizona

    Science.gov (United States)

    Hydrological characteristics in the semi-arid southwest create unique challenges to watershed modelers. Streamflow in these regions is largely dependent on seasonal, short term, and high intensity rainfall events. The objectives of this study are: 1) to analyze the unique hydrolo...

  5. Evaluation of Gridded Precipitation Data for Driving SWAT Model in Area Upstream of Three Gorges Reservoir

    Science.gov (United States)

    Yang, Yan; Wang, Guoqiang; Wang, Lijing; Yu, Jingshan; Xu, Zongxue

    2014-01-01

    Gridded precipitation data are becoming an important source for driving hydrologic models to achieve stable and valid simulation results in different regions. Thus, evaluating different sources of precipitation data is important for improving the applicability of gridded data. In this study, we used three gridded rainfall datasets: 1) National Centers for Environmental Prediction - Climate Forecast System Reanalysis (NCEP-CFSR); 2) Asian Precipitation - Highly-Resolved Observational Data Integration Towards Evaluation (APHRODITE); and 3) China trend - surface reanalysis (trend surface) data. These are compared with monitoring precipitation data for driving the Soil and Water Assessment Tool in two basins upstream of Three Gorges Reservoir (TGR) in China. The results of one test basin with significant topographic influence indicates that all the gridded data have poor abilities in reproducing hydrologic processes with the topographic influence on precipitation quantity and distribution. However, in a relatively flat test basin, the APHRODITE and trend surface data can give stable and desirable results. The results of this study suggest that precipitation data for future applications should be considered comprehensively in the TGR area, including the influence of data density and topography. PMID:25409467

  6. Evaluation of gridded precipitation data for driving SWAT model in area upstream of Three Gorges Reservoir.

    Science.gov (United States)

    Yang, Yan; Wang, Guoqiang; Wang, Lijing; Yu, Jingshan; Xu, Zongxue

    2014-01-01

    Gridded precipitation data are becoming an important source for driving hydrologic models to achieve stable and valid simulation results in different regions. Thus, evaluating different sources of precipitation data is important for improving the applicability of gridded data. In this study, we used three gridded rainfall datasets: 1) National Centers for Environmental Prediction-Climate Forecast System Reanalysis (NCEP-CFSR); 2) Asian Precipitation-Highly-Resolved Observational Data Integration Towards Evaluation (APHRODITE); and 3) China trend-surface reanalysis (trend surface) data. These are compared with monitoring precipitation data for driving the Soil and Water Assessment Tool in two basins upstream of Three Gorges Reservoir (TGR) in China. The results of one test basin with significant topographic influence indicates that all the gridded data have poor abilities in reproducing hydrologic processes with the topographic influence on precipitation quantity and distribution. However, in a relatively flat test basin, the APHRODITE and trend surface data can give stable and desirable results. The results of this study suggest that precipitation data for future applications should be considered comprehensively in the TGR area, including the influence of data density and topography.

  7. Calibration of spatially distributed hydrological processes and model parameters in SWAT using remote sensing data and an auto-calibration procedure : A case study in a Vietnamese river basin

    NARCIS (Netherlands)

    Hà, T.L.; Bastiaanssen, W.G.M.; van Griensven, Ann; Van Dijk, Albert I J M; Senay, Gabriel B.

    2018-01-01

    In this paper, evapotranspiration (ET) and leaf area index (LAI) were used to calibrate the SWAT model, whereas remotely sensed precipitation and other climatic parameters were used as forcing data for the 6300 km2 Day Basin, a tributary of the Red River in Vietnam. The efficacy of the Sequential

  8. Applying the SWAT hydrologic model on a watershed containing forested karst.

    Science.gov (United States)

    Devendra M. Amatya; Amy E. Edwards

    2009-01-01

    The US Forest Service Center for Forested Wetlands Research is working on a South Carolina Department of Health and Environmental Control (SC DHEC)'s Section 319 Grant Program funded Total Maximum Daily Load (TMDL) project for the watershed of Chapel Branch Creek (CBC) draining to Lake Marion in Santee, South Carolina (Fig. 1)....

  9. Critical review of SWAT applications in the upper Nile basin countries

    Directory of Open Access Journals (Sweden)

    A. van Griensven

    2012-09-01

    Full Text Available The Soil and Water Assessment Tool (SWAT is an integrated river basin model that is widely applied within the Nile basin. Up to date, more than 20 peer-reviewed papers describe the use of SWAT for a variety of problems in the upper Nile basin countries, such as erosion modelling, land use and climate change impact modelling and water resources management. The majority of the studies are focused on locations in the tropical highlands in Ethiopia and around Lake Victoria. The popularity of SWAT is attributed to the fact that the tool is freely available and that it is readily applicable through the development of geographic information system (GIS based interfaces and its easy linkage to sensitivity, calibration and uncertainty analysis tools. The online and free availability of basic GIS data that are required for SWAT made its applicability more straightforward even in data-scarce areas. However, the easy use of SWAT may not always lead to appropriate models which is also a consequence of the quality of the available free databases in these regions. In this paper, we aim at critically reviewing the use of SWAT in the context of the modelling purpose and problem descriptions in the tropical highlands of the Nile basin countries. To evaluate the models that are described in journal papers, a number of criteria are used to evaluate the model set-up, model performances, physical representation of the model parameters, and the correctness of the hydrological model balance. On the basis of performance indicators, the majority of the SWAT models were classified as giving satisfactory to very good results. Nevertheless, the hydrological mass balances as reported in several papers contained losses that might not be justified. Several papers also reported the use of unrealistic parameter values. More worrying is that many papers lack this information. For this reason, most of the reported SWAT models have to be evaluated critically. An important gap is

  10. Cost-effectiveness and cost-benefit analysis of BMPs in controlling agricultural nonpoint source pollution in China based on the SWAT model.

    Science.gov (United States)

    Liu, Ruimin; Zhang, Peipei; Wang, Xiujuan; Wang, Jiawei; Yu, Wenwen; Shen, Zhenyao

    2014-12-01

    Best management practices (BMPs) have been widely used in managing agricultural nonpoint source pollution (ANSP) at the watershed level. Most BMPs are related to land use, tillage management, and fertilizer levels. In total, seven BMP scenarios (Reforest1, Reforest2, No Tillage, Contour tillage, and fertilizer level 1-4) that are related to these three factors were estimated in this study. The objectives were to investigate the effectiveness and cost-benefit of these BMPs on ANSP reduction in a large tributary of the Three Gorges Reservoir (TGR) in China, which are based on the simulation results of the Soil and Water Assessment Tool (SWAT) model. The results indicated that reforestation was the most economically efficient of all BMPs, and its net benefits were up to CNY 4.36×10(7) years(-1) (about USD 7.08×10(6) years(-1)). Regarding tillage practices, no tillage practice was more environmentally friendly than other tillage practices, and contour tillage was more economically efficient. Reducing the local fertilizer level to 0.8-fold less than that of 2010 can yield a satisfactory environmental and economic efficiency. Reforestation and fertilizer management were more effective in reducing total phosphorus (TP), whereas tillage management was more effective in reducing total nitrogen (TN). When CNY 10,000 (about USD 162) was applied to reforestation, no tillage, contour tillage, and an 0.8-fold reduction in the fertilizer level, then annual TN load can be reduced by 0.08, 0.16, 0.11, and 0.04 t and annual TP load can be reduced by 0.04, 0.02, 0.01 and 0.03 t, respectively. The cost-benefit (CB) ratios of the BMPs were as follows: reforestation (207 %) > contour tillage (129 %) > no tillage (114 %) > fertilizer management (96 and 89 %). The most economical and effective BMPs can be designated as follows: BMP1 (returning arable land with slopes greater than 25° to forests and those lands with slopes of 15-25° to orchards), BMP2 (implementing no tillage

  11. Validation of integrated burnup code system SWAT2 by the analyses of isotopic composition of spent nuclear fuel

    International Nuclear Information System (INIS)

    Suyama, K.; Mochizuki, H.; Okuno, H.; Miyoshi, Y.

    2004-01-01

    This paper provides validation results of SWAT2, the revised version of SWAT, which is a code system combining point burnup code ORIGEN2 and continuous energy Monte Carlo code MVP, by the analysis of post irradiation examinations (PIEs). Some isotopes show differences of calculation results between SWAT and SWAT2. However, generally, the differences are smaller than the error of PIE analysis that was reported in previous SWAT validation activity, and improved results are obtained for several important fission product nuclides. This study also includes comparison between an assembly and a single pin cell geometry models. (authors)

  12. Applying Spatially Distributed Rainfall to a Hydrological Model in a Tropical Watershed, Manoa Watershed, in Hawaii

    Science.gov (United States)

    Huang, Y. F.; Tsang, Y. P.

    2017-12-01

    Rainfall in Hawaii is characterized with high spatial and temporal variability. In the south side of Oahu, the Manoa watershed, with an area of 11 km2, has the annual maximum rainfall of 3900mm and the minimum rainfall of 1000 mm. Despite this high spatial heterogeneity, the rain gage network seems insufficiently capture this pattern. When simulating stream flow and predicting floods with hydrological models in Hawaii, the model performance is often unsatisfactory because of inadequate representation of rainfall data. Longman et al. (in prep.) have developed the spatially distributed daily rainfall across the Hawaiian Islands by applying ordinary kriging, yet these data have not been applied to hydrological models. In this study, we used the Soil and Water Assessment Tool (SWAT) model to assess the streamflow simulation by applying spatially-distributed rainfall in the Manoa watershed. We first used point daily-rainfall at Lyon Arboretum from National Center of Environmental Information (NCEI) as the uniform rainfall input. Secondly, we summarized sub-watershed mean rainfall from the daily spatial-statistical rainfall. Both rainfall data are available from 1999 to 2014. The SWAT was set up for five-year warm-up, nine-year calibration, and two-year validation. The model parameters were calibrated and validated with four U.S. Geological Survey stream gages. We compared the calibrated watershed parameters, characteristics, and assess the streamflow hydrographs from these two rainfall inputs. The differences and improvement of using spatially distributed rainfall input in SWAT were discussed. In addition to improving the model by the representation of rainfall, this study helped us having a better understanding of the watershed hydrological response in Hawaii.

  13. Applied stochastic modelling

    CERN Document Server

    Morgan, Byron JT; Tanner, Martin Abba; Carlin, Bradley P

    2008-01-01

    Introduction and Examples Introduction Examples of data sets Basic Model Fitting Introduction Maximum-likelihood estimation for a geometric model Maximum-likelihood for the beta-geometric model Modelling polyspermy Which model? What is a model for? Mechanistic models Function Optimisation Introduction MATLAB: graphs and finite differences Deterministic search methods Stochastic search methods Accuracy and a hybrid approach Basic Likelihood ToolsIntroduction Estimating standard errors and correlations Looking at surfaces: profile log-likelihoods Confidence regions from profiles Hypothesis testing in model selectionScore and Wald tests Classical goodness of fit Model selection biasGeneral Principles Introduction Parameterisation Parameter redundancy Boundary estimates Regression and influence The EM algorithm Alternative methods of model fitting Non-regular problemsSimulation Techniques Introduction Simulating random variables Integral estimation Verification Monte Carlo inference Estimating sampling distributi...

  14. SWATMOD-PREP: Graphical user interface for preparing coupled SWAT-modflow simulations

    Science.gov (United States)

    This paper presents SWATMOD-Prep, a graphical user interface that couples a SWAT watershed model with a MODFLOW groundwater flow model. The interface is based on a recently published SWAT-MODFLOW code that couples the models via mapping schemes. The spatial layout of SWATMOD-Prep guides the user t...

  15. Applied Bayesian modelling

    CERN Document Server

    Congdon, Peter

    2014-01-01

    This book provides an accessible approach to Bayesian computing and data analysis, with an emphasis on the interpretation of real data sets. Following in the tradition of the successful first edition, this book aims to make a wide range of statistical modeling applications accessible using tested code that can be readily adapted to the reader's own applications. The second edition has been thoroughly reworked and updated to take account of advances in the field. A new set of worked examples is included. The novel aspect of the first edition was the coverage of statistical modeling using WinBU

  16. Application Of Hydrological Models In Poorly Gauged Watersheds A Review Of The Usage Of The Soil And Water Assessment Tool SWAT In Kenya

    Directory of Open Access Journals (Sweden)

    Wambugu Mwangi

    2017-08-01

    Full Text Available In water-scarce developing countries river basins are some of the most valued natural resources but many are poorly gauged and have incomplete hydrological and climate records. In the recent years tropical rivers are increasingly becoming erratic with many hydrologists attributing this variability to combined effects of landscape-specific anthropogenic activities and climate change. Uncertainties about the impacts of climate change compound the challenges attributed to poor and often inconsistent river monitoring data. Under data-scarce conditions and with the increasing land use intensification and urbanization modelling approaches become a useful tool in planning and management of water resources. In this paper we review the application and usability of the Soil and Water Assessment Tool SWAT model in conventional planning practice in the management of water resources is poorly-gauged tropical watersheds of Kenya. We assess the technical implications of the model in Intergrated Water Resources management IWRM and its applicability as a planning and management tool for water resources in the era of climate change.

  17. Calibration of a Field-Scale Soil and Water Assessment Tool (SWAT Model with Field Placement of Best Management Practices in Alger Creek, Michigan

    Directory of Open Access Journals (Sweden)

    Katherine R. Merriman

    2018-03-01

    Full Text Available Subwatersheds within the Great Lakes “Priority Watersheds” were targeted by the Great Lakes Restoration Initiative (GLRI to determine the effectiveness of the various best management practices (BMPs from the U.S. Department of Agriculture-Natural Resources Conservation Service National Conservation Planning (NCP Database. A Soil and Water Assessment Tool (SWAT model is created for Alger Creek, a 50 km2 tributary watershed to the Saginaw River in Michigan. Monthly calibration yielded very good Nash–Sutcliffe efficiency (NSE ratings for flow, sediment, total phosphorus (TP, dissolved reactive phosphorus (DRP, and total nitrogen (TN (0.90, 0.79, 0.87, 0.88, and 0.77, respectively, and satisfactory NSE rating for nitrate (0.51. Two-year validation results in at least satisfactory NSE ratings for flow, sediment, TP, DRP, and TN (0.83, 0.54, 0.73, 0.53, and 0.60, respectively, and unsatisfactory NSE rating for nitrate (0.28. The model estimates the effect of BMPs at the field and watershed scales. At the field-scale, the most effective single practice at reducing sediment, TP, and DRP is no-tillage followed by cover crops (CC; CC are the most effective single practice at reducing nitrate. The most effective BMP combinations include filter strips, which can have a sizable effect on reducing sediment and phosphorus loads. At the watershed scale, model results indicate current NCP BMPs result in minimal sediment and nutrient reductions (<10%.

  18. Calibration of a field-scale Soil and Water Assessment Tool (SWAT) model with field placement of best management practices in Alger Creek, Michigan

    Science.gov (United States)

    Merriman-Hoehne, Katherine R.; Russell, Amy M.; Rachol, Cynthia M.; Daggupati, Prasad; Srinivasan, Raghavan; Hayhurst, Brett A.; Stuntebeck, Todd D.

    2018-01-01

    Subwatersheds within the Great Lakes “Priority Watersheds” were targeted by the Great Lakes Restoration Initiative (GLRI) to determine the effectiveness of the various best management practices (BMPs) from the U.S. Department of Agriculture-Natural Resources Conservation Service National Conservation Planning (NCP) Database. A Soil and Water Assessment Tool (SWAT) model is created for Alger Creek, a 50 km2 tributary watershed to the Saginaw River in Michigan. Monthly calibration yielded very good Nash–Sutcliffe efficiency (NSE) ratings for flow, sediment, total phosphorus (TP), dissolved reactive phosphorus (DRP), and total nitrogen (TN) (0.90, 0.79, 0.87, 0.88, and 0.77, respectively), and satisfactory NSE rating for nitrate (0.51). Two-year validation results in at least satisfactory NSE ratings for flow, sediment, TP, DRP, and TN (0.83, 0.54, 0.73, 0.53, and 0.60, respectively), and unsatisfactory NSE rating for nitrate (0.28). The model estimates the effect of BMPs at the field and watershed scales. At the field-scale, the most effective single practice at reducing sediment, TP, and DRP is no-tillage followed by cover crops (CC); CC are the most effective single practice at reducing nitrate. The most effective BMP combinations include filter strips, which can have a sizable effect on reducing sediment and phosphorus loads. At the watershed scale, model results indicate current NCP BMPs result in minimal sediment and nutrient reductions (<10%).

  19. Improving SWAT for simulating water and carbon fluxes of forest ecosystems

    International Nuclear Information System (INIS)

    Yang, Qichun; Zhang, Xuesong

    2016-01-01

    As a widely used watershed model for assessing impacts of anthropogenic and natural disturbances on water quantity and quality, the Soil and Water Assessment Tool (SWAT) has not been extensively tested in simulating water and carbon fluxes of forest ecosystems. Here, we examine SWAT simulations of evapotranspiration (ET), net primary productivity (NPP), net ecosystem exchange (NEE), and plant biomass at ten AmeriFlux forest sites across the U.S. We identify unrealistic radiation use efficiency (Bio-E), large leaf to biomass fraction (Bio-LEAF), and missing phosphorus supply from parent material weathering as the primary causes for the inadequate performance of the default SWAT model in simulating forest dynamics. By further revising the relevant parameters and processes, SWAT's performance is substantially improved. Based on the comparison between the improved SWAT simulations and flux tower observations, we discuss future research directions for further enhancing model parameterization and representation of water and carbon cycling for forests. - Graphical abstract: Evaluating and improving SWAT simulations of water and carbon cycling over ten AmeriFlux sites across the United States. - Highlights: • The default forest parameterization in SWAT results in inadequate simulations of water and carbon. • Radiation use efficiency, leaf to biomass fraction, and parent material weathering processes are modified. • Revised SWAT provides improved simulations of evapotranspiration and net ecosystem exchange

  20. Improving SWAT for simulating water and carbon fluxes of forest ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Qichun [Joint Global Change Research Institute, Pacific Northwest National Lab, College Park, MD 20740 (United States); Zhang, Xuesong, E-mail: xuesong.zhang@pnnl.gov [Joint Global Change Research Institute, Pacific Northwest National Lab, College Park, MD 20740 (United States); Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824 (United States)

    2016-11-01

    As a widely used watershed model for assessing impacts of anthropogenic and natural disturbances on water quantity and quality, the Soil and Water Assessment Tool (SWAT) has not been extensively tested in simulating water and carbon fluxes of forest ecosystems. Here, we examine SWAT simulations of evapotranspiration (ET), net primary productivity (NPP), net ecosystem exchange (NEE), and plant biomass at ten AmeriFlux forest sites across the U.S. We identify unrealistic radiation use efficiency (Bio-E), large leaf to biomass fraction (Bio-LEAF), and missing phosphorus supply from parent material weathering as the primary causes for the inadequate performance of the default SWAT model in simulating forest dynamics. By further revising the relevant parameters and processes, SWAT's performance is substantially improved. Based on the comparison between the improved SWAT simulations and flux tower observations, we discuss future research directions for further enhancing model parameterization and representation of water and carbon cycling for forests. - Graphical abstract: Evaluating and improving SWAT simulations of water and carbon cycling over ten AmeriFlux sites across the United States. - Highlights: • The default forest parameterization in SWAT results in inadequate simulations of water and carbon. • Radiation use efficiency, leaf to biomass fraction, and parent material weathering processes are modified. • Revised SWAT provides improved simulations of evapotranspiration and net ecosystem exchange.

  1. Assessing the cumulative impacts of geographically isolated wetlands on watershed hydrology using the SWAT model coupled with improved wetland modules.

    Science.gov (United States)

    Lee, S; Yeo, I-Y; Lang, M W; Sadeghi, A M; McCarty, G W; Moglen, G E; Evenson, G R

    2018-06-07

    Despite recognizing the importance of wetlands in the Coastal Plain of the Chesapeake Bay Watershed (CBW) in terms of ecosystem services, our understanding of wetland functions has mostly been limited to individual wetlands and overall catchment-scale wetland functions have rarely been investigated. This study is aimed at assessing the cumulative impacts of wetlands on watershed hydrology for an agricultural watershed within the Coastal Plain of the CBW using the Soil and Water Assessment Tool (SWAT). We employed two improved wetland modules for enhanced representation of physical processes and spatial distribution of riparian wetlands (RWs) and geographically isolated wetlands (GIWs). This study focused on GIWs as their hydrological impacts on watershed hydrology are poorly understood and GIWs are poorly protected. Multiple wetland scenarios were prepared by removing all or portions of the baseline GIW condition indicated by the U.S. Fish and Wildlife Service National Wetlands Inventory geospatial dataset. We further compared the impacts of GIWs and RWs on downstream flow (i.e., streamflow at the watershed outlet). Our simulation results showed that GIWs strongly influenced downstream flow by altering water transport mechanisms in upstream areas. Loss of all GIWs reduced both water routed to GIWs and water infiltrated into the soil through the bottom of GIWs, leading to an increase in surface runoff of 9% and a decrease in groundwater flow of 7% in upstream areas. These changes resulted in increased variability of downstream flow in response to extreme flow conditions. GIW loss also induced an increase in month to month variability of downstream flow and a decrease in the baseflow contribution to streamflow. Loss of all GIWs was shown to cause a greater fluctuation of downstream flow than loss of all RWs for this study site, due to a greater total water storage capacity of GIWs. Our findings indicate that GIWs play a significant role in controlling hydrological

  2. Assessment of TRMM Products and Their Influence on Hydrologic Models within the Middle East and North Africa (MENA) Region Using the Soil and Water Assessment Tool (SWAT)

    Science.gov (United States)

    Milewski, A.; El Kadiri, R.; Durham, M. C.

    2013-12-01

    Satellite remote sensing datasets have been increasingly employed as an ancillary source of essential hydrologic measurements used for the modeling of hydrologic fluxes. Precipitation is one of the most important meteorological forcing parameter in hydrological investigations and land surface modeling, yet it is largely unknown or misused in water budgets and hydrologic models. The Tropical Rainfall Measurement Mission (TRMM) satellite products are widely being used by the scientific community due to the general spatial and temporal paucity of precipitation data in many parts of world and particularly in the Middle East and North Africa (MENA) region. This research utilized a two-fold approach towards understanding the accuracy of satellite-based rainfall and its application in hydrologic models First, we evaluated the uncertainty, accuracy, and precision of various rainfall satellite products (i.e. TRMM 3B42 V6, TRMM 3B42 V7, TRMM 3B42 V7a and TRMM 3B42 RT) in comparison to in situ gauge data from more than 150 rain gauges in Morocco and across the MENA region. Our analyses extend over many parts of the MENA region in order to assess the effect that different climatic regimes and topographic characteristics have on each TRMM product. Secondly, we analyzed and compared the hydrologic fluxes produced from different modeling inputs for several watersheds within the MENA region. SWAT (Soil and Water Assessment Tool) hydrologic models have been developed for the Oum Er Rbia (Morocco), Asyuti (Egypt), and the Sakarya (Turkey) watersheds. SWAT models produced for each watershed include, one model for each of the four satellite TRMM product (STBM-V6, STBM-V7, STBM-V7a, and STBM-RT) and one model for rain gauge based model (RGBM). Findings indicate the best correlation between field-based and satellite-based rainfall measurements is the TRMM V7a (Pearson coefficient: 0.875) product, followed by TRMM V7 (Pearson coefficient: 0.84), then TRMM V6 (Pearson coefficient: 0

  3. Multi-gauge Calibration for modeling the Semi-Arid Santa Cruz Watershed in Arizona-Mexico Border Area Using SWAT

    Science.gov (United States)

    Niraula, Rewati; Norman, Laura A.; Meixner, Thomas; Callegary, James B.

    2012-01-01

    In most watershed-modeling studies, flow is calibrated at one monitoring site, usually at the watershed outlet. Like many arid and semi-arid watersheds, the main reach of the Santa Cruz watershed, located on the Arizona-Mexico border, is discontinuous for most of the year except during large flood events, and therefore the flow characteristics at the outlet do not represent the entire watershed. Calibration is required at multiple locations along the Santa Cruz River to improve model reliability. The objective of this study was to best portray surface water flow in this semiarid watershed and evaluate the effect of multi-gage calibration on flow predictions. In this study, the Soil and Water Assessment Tool (SWAT) was calibrated at seven monitoring stations, which improved model performance and increased the reliability of flow, in the Santa Cruz watershed. The most sensitive parameters to affect flow were found to be curve number (CN2), soil evaporation and compensation coefficient (ESCO), threshold water depth in shallow aquifer for return flow to occur (GWQMN), base flow alpha factor (Alpha_Bf), and effective hydraulic conductivity of the soil layer (Ch_K2). In comparison, when the model was established with a single calibration at the watershed outlet, flow predictions at other monitoring gages were inaccurate. This study emphasizes the importance of multi-gage calibration to develop a reliable watershed model in arid and semiarid environments. The developed model, with further calibration of water quality parameters will be an integral part of the Santa Cruz Watershed Ecosystem Portfolio Model (SCWEPM), an online decision support tool, to assess the impacts of climate change and urban growth in the Santa Cruz watershed.

  4. Evaluating watershed protection programs in New York City's Cannonsville Reservoir source watershed using SWAT-HS

    Science.gov (United States)

    Hoang, L.; Mukundan, R.; Moore, K. E.; Owens, E. M.; Steenhuis, T. S.

    2017-12-01

    New York City (NYC)'s reservoirs supply over one billion gallons of drinking water each day to over nine million consumers in NYC and upstate communities. The City has invested more than $1.5 billion in watershed protection programs to maintain a waiver from filtration for the Catskill and Delaware Systems. In the last 25 years, the NYC Department of Environmental Protection (NYCDEP) has implemented programs in cooperation with upstate communities that include nutrient management, crop rotations, improvement of barnyards and manure storage, implementing tertiary treatment for Phosphorus (P) in wastewater treatment plants, and replacing failed septic systems in an effort to reduce P loads to water supply reservoirs. There have been several modeling studies evaluating the effect of agricultural Best Management Practices (BMPs) on P control in the Cannonsville watershed in the Delaware System. Although these studies showed that BMPs would reduce dissolved P losses, they were limited to farm-scale or watershed-scale estimates of reduction factors without consideration of the dynamic nature of overland flow and P losses from variable source areas. Recently, we developed the process-based SWAT-Hillslope (SWAT-HS) model, a modified version of the Soil and Water Assessment Tool (SWAT) that can realistically predict variable source runoff processes. The objective of this study is to use the SWAT-HS model to evaluate watershed protection programs addressing both point and non-point sources of P. SWAT-HS predicts streamflow very well for the Cannonsville watershed with a daily Nash Sutcliffe Efficiency (NSE) of 0.85 at the watershed outlet and NSE values ranging from 0.56 - 0.82 at five other locations within the watershed. Based on good hydrological prediction, we applied the model to predict P loads using detailed P inputs that change over time due to the implementation of watershed protection programs. Results from P model predictions provide improved projections of P

  5. Future water availability in the largest freshwater Mediterranean lake is at great risk as evidenced from simulations with the SWAT model.

    Science.gov (United States)

    Bucak, Tuba; Trolle, Dennis; Andersen, Hans Estrup; Thodsen, Hans; Erdoğan, Şeyda; Levi, Eti E; Filiz, Nur; Jeppesen, Erik; Beklioğlu, Meryem

    2017-03-01

    Inter- and intra-annual water level fluctuations and changes in water flow regime are intrinsic characteristics of Mediterranean lakes. Additionally, considering climate change projections for the water-limited Mediterranean region, increased air temperatures and decreased precipitation are anticipated, leading to dramatic declines in lake water levels as well as severe water scarcity problems. The study site, Lake Beyşehir, the largest freshwater lake in the Mediterranean basin, is - like other Mediterranean lakes - threatened by climatic changes and over-abstraction of water for irrigated crop farming. Therefore, implementation of strict water level management policies is required. In this study, an integrated modeling approach was used to predict the future water levels of Lake Beyşehir in response to potential future changes in climate and land use. Water level estimation was performed by linking the catchment model Soil and Water Assessment Tool (SWAT) with a Support Vector Regression model (ε-SVR). The projected increase in temperature and decrease in precipitation based on the climate change models led to an enhanced potential evapotranspiration and reduced total runoff. On the other hand, the effects of various land use scenarios within the catchment appeared to be comparatively insignificant. According to the ε-SVR model results, changes in hydrological processes caused a water level reduction for all scenarios. Moreover, the MPI-ESM-MR General Circulation Model outputs produced the most dramatic results by predicting that Lake Beyşehir may dry out by the 2040s with the current outflow regime. The results indicate that shallow Mediterranean lakes may face a severe risk of drying out and losing their ecosystem values in the near future if the current intensity of water abstraction is not reduced. In addition, the results also demonstrate that outflow management and sustainable use of water sources are vital to sustain lake ecosystems in water

  6. Fecal bacteria source characterization and sensitivity analysis of SWAT 2005

    Science.gov (United States)

    The Soil and Water Assessment Tool (SWAT) version 2005 includes a microbial sub-model to simulate fecal bacteria transport at the watershed scale. The objectives of this study were to demonstrate methods to characterize fecal coliform bacteria (FCB) source loads and to assess the model sensitivity t...

  7. Pesticide transport simulation in a tropical catchment by SWAT

    International Nuclear Information System (INIS)

    Bannwarth, M.A.; Sangchan, W.; Hugenschmidt, C.; Lamers, M.; Ingwersen, J.; Ziegler, A.D.; Streck, T.

    2014-01-01

    The application of agrochemicals in Southeast Asia is increasing in rate, variety and toxicity with alarming speed. Understanding the behavior of these different contaminants within the environment require comprehensive monitoring programs as well as accurate simulations with hydrological models. We used the SWAT hydrological model to simulate the fate of three different pesticides, one of each usage type (herbicide, fungicide and insecticide) in a mountainous catchment in Northern Thailand. Three key parameters were identified: the sorption coefficient, the decay coefficient and the coefficient controlling pesticide percolation. We yielded satisfactory results simulating pesticide load dynamics during the calibration period (NSE: 0.92–0.67); the results during the validation period were also acceptable (NSE: 0.61–0.28). The results of this study are an important step in understanding the modeling behavior of these pesticides in SWAT and will help to identify thresholds of worst-case scenarios in order to assess the risk for the environment. - Highlights: • We performed a global LH-sensitivity analysis of all pesticide related parameters. • Key physical parameters are associated to percolation, degradation and sorption. • We simulated the measured loads of three different pesticides. • We performed an uncertainty analysis of all pesticide simulations. • All Pesticides differed considerably in their sensitivity and simulation behavior. - Pesticide load simulations of three pesticides were modeled by SWAT, providing clues on how to handle pesticides in future SWAT studies

  8. Příprava podkladů pro modelování odtoku a odnosu látek v prostředí SWAT

    OpenAIRE

    HOMOLKA, Jan

    2012-01-01

    This bachelor thesis is dealing with preparation bases for modelation draining and carrying materials in SWAT model. Thesis includes literature search about basis of SWAT model, SWAT development, preferences and imprefections of this model. It?s also going over various modelations and general division. Further describes necessary input data, their types and requirements without which would be impossible to complete this task. I?ve chosen Jenín stream basin located near village Jenín which is ...

  9. Application of SWAT to assess the effects of land use change in the Murchison Bay catchment in Uganda

    Science.gov (United States)

    The Soil and Water Assessment Tool (SWAT) is a versatile model presently used worldwide to evaluate water quality and hydrological concerns under varying land use and environmental conditions. In this study, SWAT was used to simulate streamflow and to estimate sediment yield and nutrients loss from ...

  10. Improving SWAT for simulating water and carbon fluxes of forest ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Qichun; Zhang, Xuesong

    2016-11-01

    As a widely used watershed model for assessing impacts of anthropogenic and natural disturbances on water quantity and quality, the Soil and Water Assessment Tool (SWAT) has not been extensively tested in simulating water and carbon fluxes of forest ecosystems. Here, we examine SWAT simulations of evapotranspiration (ET), net primary productivity (NPP), net ecosystem exchange (NEE), and plant biomass at ten AmeriFlux forest sites across the U.S. We identify unrealistic radiation use efficiency (Bio_E), large leaf to biomass fraction (Bio_LEAF), and missing phosphorus supply from parent material weathering as the primary causes for the inadequate performance of the default SWAT model in simulating forest dynamics. By further revising the relevant parameters and processes, SWAT’s performance is substantially improved. Based on the comparison between the improved SWAT simulations and flux tower observations, we discuss future research directions for further enhancing model parameterization and representation of water and carbon cycling for forests.

  11. Assessing the impacts of future climate conditions on the effectiveness of winter cover crops in reducing nitrate loads into the Chesapeake Bay Watershed using SWAT model

    Science.gov (United States)

    Lee, Sangchul; Sadeghi, Ali M.; Yeo, In-Young; McCarty, Gregory W.; Hively, W. Dean

    2017-01-01

    Winter cover crops (WCCs) have been widely implemented in the Coastal Plain of the Chesapeake Bay watershed (CBW) due to their high effectiveness at reducing nitrate loads. However, future climate conditions (FCCs) are expected to exacerbate water quality degradation in the CBW by increasing nitrate loads from agriculture. Accordingly, the question remains whether WCCs are sufficient to mitigate increased nutrient loads caused by FCCs. In this study, we assessed the impacts of FCCs on WCC nitrate reduction efficiency on the Coastal Plain of the CBW using Soil and Water Assessment Tool (SWAT) model. Three FCC scenarios (2085 – 2098) were prepared using General Circulation Models (GCMs), considering three Intergovernmnental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) greenhouse gas emission scenarios. We also developed six representative WCC implementation scenarios based on the most commonly used planting dates and species of WCCs in this region. Simulation results showed that WCC biomass increased by ~ 58 % under FCC scenarios, due to climate conditions conducive to the WCC growth. Prior to implementing WCCs, annual nitrate loads increased by ~ 43 % under FCC scenarios compared to the baseline scenario (2001 – 2014). When WCCs were planted, annual nitrate loads were substantially reduced by ~ 48 % and WCC nitrate reduction efficiency water ~ 5 % higher under FCC scenarios relative to the baseline. The increase rate of WCC nitrate reduction efficiency varied by FCC scenarios and WCC planting methods. As CO2 concentration was higher and winters were warmer under FCC scenarios, WCCs had greater biomass and therefore showed higher nitrate reduction efficiency. In response to FCC scenarios, the performance of less effective WCC practices (e.g., barley, wheat, and late planting) under the baseline indicated ~ 14 % higher increase rate of nitrate reduction efficiency compared to ones with better effectiveness under the baseline (e

  12. Improving the spatial representation of soil properties and hydrology using topographically derived initialization processes in the SWAT model

    Science.gov (United States)

    Topography exerts critical controls on many hydrologic, geomorphologic, and environmental biophysical processes. Unfortunately many watershed modeling systems use topography only to define basin boundaries and stream channels and do not explicitly account for the topographic controls on processes su...

  13. Prediction of land use changes based on land change modeler and attribution of changes in the water balance of Ganga basin to land use change using the SWAT model

    Science.gov (United States)

    Anand, J.; Gosain, A. K.; Khosa, R.

    2017-12-01

    Conflicts between increasing irrigated agricultural area, commercial crops, shifting cultivation and ever increasing domestic and industrial demand has already been a cause of tension in the society over water in the Ganga River Basin, India. For the development of sustainable water resource strategies, it is essential to establish interaction between landuse changes and local hydrology through proper assessment. Precisely, seeing how change in each LULC affects hydrologic regimes, or conversely evaluating which LULC shall be appropriate for the local hydrological regime can help decision makers to incorporate in the policy instruments. In this study, we assess hydrologic regimes of the Ganga River basin with landuse change. Catchment hydrologic responses were simulated using Soil and Water Assessment Tool (SWAT). Meteorological data from IMD of 0.25°×0.25° spatial resolution were taken as the climate inputs. Simulated stream flow was compared at different gauge stations distributed across the Gang basin and its tributaries. Urbanization was the topmost contributor to the increase in surface runoff and water yield. While, increased irrigation demands was the dominant contributor to the water consumption and also added to the increased evapotranspiration. In addition scenarios have been generated to study the impact of landuse change on various components of hydrology including groundwater recharge, with different cropping patterns and increased irrigation efficiency to determine various mitigation strategies that can be adopted. This study can be important tool in quantifying the changes in hydrological components in response to changes made in landuse in especially basins undergoing rapid commercialization. This shall provide substantive information to the decision makers required to develop ameliorative strategies. Keywords: Landuse and Landcover change, Hydrologic model, Soil Water Assessment Tool (SWAT), Urbanization, Ganga River, Watershed hydrology.

  14. Improving the performance of temperature index snowmelt model of SWAT by using MODIS land surface temperature data.

    Science.gov (United States)

    Yang, Yan; Onishi, Takeo; Hiramatsu, Ken

    2014-01-01

    Simulation results of the widely used temperature index snowmelt model are greatly influenced by input air temperature data. Spatially sparse air temperature data remain the main factor inducing uncertainties and errors in that model, which limits its applications. Thus, to solve this problem, we created new air temperature data using linear regression relationships that can be formulated based on MODIS land surface temperature data. The Soil Water Assessment Tool model, which includes an improved temperature index snowmelt module, was chosen to test the newly created data. By evaluating simulation performance for daily snowmelt in three test basins of the Amur River, performance of the newly created data was assessed. The coefficient of determination (R (2)) and Nash-Sutcliffe efficiency (NSE) were used for evaluation. The results indicate that MODIS land surface temperature data can be used as a new source for air temperature data creation. This will improve snow simulation using the temperature index model in an area with sparse air temperature observations.

  15. Attribution of changes in the water balance of a tropical catchment to land use change using the SWAT model

    NARCIS (Netherlands)

    Marhaento, Hero; Booij, Martijn J.; Rientjes, T. H.M.; Hoekstra, Arjen Y.

    2017-01-01

    Changes in the water balance of the Samin catchment (277.9 km2) on Java, Indonesia, can be attributed to land use change using the Soil Water Assessment Tool model. A baseline-altered method was used in which the simulation period 1990–2013 was divided into 4 equal periods to represent baseline

  16. Adequacy of TRMM satellite rainfall data in driving the SWAT modeling of Tiaoxi catchment (Taihu lake basin, China)

    Science.gov (United States)

    Li, Dan; Christakos, George; Ding, Xinxin; Wu, Jiaping

    2018-01-01

    Spatial rainfall data is an essential input to Distributed Hydrological Models (DHM), and a significant contributor to hydrological model uncertainty. Model uncertainty is higher when rain gauges are sparse, as is often the case in practice. Currently, satellite-based precipitation products increasingly provide an alternative means to ground-based rainfall estimates, in which case a rigorous product assessment is required before implementation. Accordingly, the twofold objective of this work paper was the real-world assessment of both (a) the Tropical Rainfall Measuring Mission (TRMM) rainfall product using gauge data, and (b) the TRMM product's role in forcing data for hydrologic simulations in the area of the Tiaoxi catchment (Taihu lake basin, China). The TRMM rainfall products used in this study are the Version-7 real-time 3B42RT and the post-real-time 3B42. It was found that the TRMM rainfall data showed a superior performance at the monthly and annual scales, fitting well with surface observation-based frequency rainfall distributions. The Nash-Sutcliffe Coefficient of Efficiency (NSCE) and the relative bias ratio (BIAS) were used to evaluate hydrologic model performance. The satisfactory performance of the monthly runoff simulations in the Tiaoxi study supports the view that the implementation of real-time 3B42RT allows considerable room for improvement. At the same time, post-real-time 3B42 can be a valuable tool of hydrologic modeling, water balance analysis, and basin water resource management, especially in developing countries or at remote locations in which rainfall gauges are scarce.

  17. Revised SWAT. The integrated burnup calculation code system

    Energy Technology Data Exchange (ETDEWEB)

    Suyama, Kenya; Mochizuki, Hiroki [Department of Fuel Cycle Safety Research, Nuclear Safety Research Center, Tokai Research Establishment, Japan Atomic Energy Research Institute, Tokai, Ibaraki (Japan); Kiyosumi, Takehide [The Japan Research Institute, Ltd., Tokyo (Japan)

    2000-07-01

    SWAT is an integrated burnup code system developed for analysis of post irradiation examination, transmutation of radioactive waste, and burnup credit problem. This report shows an outline and a user's manual of revised SWAT. This revised SWAT includes expansion of functions, increasing supported machines, and correction of several bugs reported from users of previous SWAT. (author)

  18. Revised SWAT. The integrated burnup calculation code system

    International Nuclear Information System (INIS)

    Suyama, Kenya; Mochizuki, Hiroki; Kiyosumi, Takehide

    2000-07-01

    SWAT is an integrated burnup code system developed for analysis of post irradiation examination, transmutation of radioactive waste, and burnup credit problem. This report shows an outline and a user's manual of revised SWAT. This revised SWAT includes expansion of functions, increasing supported machines, and correction of several bugs reported from users of previous SWAT. (author)

  19. Modeling the Effects of Onsite Wastewater Treatment Systems on Nitrate Loads Using SWAT in an Urban Watershed of Metropolitan Atlanta.

    Science.gov (United States)

    Hoghooghi, Nahal; Radcliffe, David E; Habteselassie, Mussie Y; Jeong, Jaehak

    2017-05-01

    Onsite wastewater treatment systems (OWTSs) can be a source of nitrogen (N) pollution in both surface and ground waters. In metropolitan Atlanta, GA, >26% of homes are on OWTSs. In a previous article, we used the Soil Water Assessment Tool to model the effect of OWTSs on stream flow in the Big Haynes Creek Watershed in metropolitan Atlanta. The objective of this study was to estimate the effect of OWTSs, including failing systems, on nitrate as N (NO-N) load in the same watershed. Big Haynes Creek has a drainage area of 44 km with mainly urban land use (67%), and most of the homes use OWTSs. A USGS gauge station where stream flow was measured daily and NO-N concentrations were measured monthly was used as the outlet. The model was simulated for 12 yr. Overall, the model showed satisfactory daily stream flow and NO-N loads with Nash-Sutcliffe coefficients of 0.62 and 0.58 for the calibration period and 0.67 and 0.33 for the validation period at the outlet of the Big Haynes Watershed. Onsite wastewater treatment systems caused an average increase in NO-N load of 23% at the watershed scale and 29% at the outlet of a subbasin with the highest density of OWTSs. Failing OWTSs were estimated to be 1% of the total systems and did not have a large impact on stream flow or NO-N load. The NO-N load was 74% of the total N load in the watershed, indicating the important effect of OWTSs on stream loads in this urban watershed. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  20. Improvement of the R-SWAT-FME framework to support multiple variables and multi-objective functions

    Science.gov (United States)

    Wu, Yiping; Liu, Shu-Guang

    2014-01-01

    Application of numerical models is a common practice in the environmental field for investigation and prediction of natural and anthropogenic processes. However, process knowledge, parameter identifiability, sensitivity, and uncertainty analyses are still a challenge for large and complex mathematical models such as the hydrological/water quality model, Soil and Water Assessment Tool (SWAT). In this study, the previously developed R program language-SWAT-Flexible Modeling Environment (R-SWAT-FME) was improved to support multiple model variables and objectives at multiple time steps (i.e., daily, monthly, and annually). This expansion is significant because there is usually more than one variable (e.g., water, nutrients, and pesticides) of interest for environmental models like SWAT. To further facilitate its easy use, we also simplified its application requirements without compromising its merits, such as the user-friendly interface. To evaluate the performance of the improved framework, we used a case study focusing on both streamflow and nitrate nitrogen in the Upper Iowa River Basin (above Marengo) in the United States. Results indicated that the R-SWAT-FME performs well and is comparable to the built-in auto-calibration tool in multi-objective model calibration. Overall, the enhanced R-SWAT-FME can be useful for the SWAT community, and the methods we used can also be valuable for wrapping potential R packages with other environmental models.

  1. Calibration of Spatially Distributed Hydrological Processes and Model Parameters in SWAT Using Remote Sensing Data and an Auto-Calibration Procedure: A Case Study in a Vietnamese River Basin

    Directory of Open Access Journals (Sweden)

    Lan Thanh Ha

    2018-02-01

    Full Text Available In this paper, evapotranspiration (ET and leaf area index (LAI were used to calibrate the SWAT model, whereas remotely sensed precipitation and other climatic parameters were used as forcing data for the 6300 km2 Day Basin, a tributary of the Red River in Vietnam. The efficacy of the Sequential Uncertainty Fitting (SUFI-2 parameter sensitivity and optimization model was tested with area specific remote sensing input parameters for every Hydrological Response Units (HRU, rather than with measurements of river flow representing a large set of HRUs, i.e., a bulk calibration. Simulated monthly ET correlations with remote sensing estimates showed an R2 = 0.71, Nash–Sutcliffe Efficiency NSE = 0.65, and Kling Gupta Efficiency KGE = 0.80 while monthly LAI showed correlations of R2 = 0.59, NSE = 0.57 and KGE = 0.83 over a five-year validation period. Accumulated modelled ET over the 5-year calibration period amounted to 5713 mm compared to 6015 mm of remotely sensed ET, yielding a difference of 302 mm (5.3%. The monthly flow at two flow measurement stations were adequately estimated (R2 = 0.78 and 0.55, NSE = 0.71 and 0.63, KGE = 0.59 and 0.75 for Phu Ly and Ninh Binh, respectively. This outcome demonstrates the capability of SWAT model to obtain spatial and accurate simulation of eco-hydrological processes, also when rivers are ungauged and the water withdrawal system is complex.

  2. Integrated burnup calculation code system SWAT

    International Nuclear Information System (INIS)

    Suyama, Kenya; Hirakawa, Naohiro; Iwasaki, Tomohiko.

    1997-11-01

    SWAT is an integrated burnup code system developed for analysis of post irradiation examination, transmutation of radioactive waste, and burnup credit problem. It enables us to analyze the burnup problem using neutron spectrum depending on environment of irradiation, combining SRAC which is Japanese standard thermal reactor analysis code system and ORIGEN2 which is burnup code widely used all over the world. SWAT makes effective cross section library based on results by SRAC, and performs the burnup analysis with ORIGEN2 using that library. SRAC and ORIGEN2 can be called as external module. SWAT has original cross section library on based JENDL-3.2 and libraries of fission yield and decay data prepared from JNDC FP Library second version. Using these libraries, user can use latest data in the calculation of SWAT besides the effective cross section prepared by SRAC. Also, User can make original ORIGEN2 library using the output file of SWAT. This report presents concept and user's manual of SWAT. (author)

  3. Impact assessment of salt iodization on the prevalence of goiter in district Swat

    International Nuclear Information System (INIS)

    Akhtar, J.; Zahoor-Ullah; Paracha, P.I.; Lutfullah, G.

    2004-01-01

    Background: To eliminate Iodine Deficiency Disorders, (IDD) universal salt iodization is the widely practiced intervention. District Swat (a hilly area of NWFP, highly endemic for IDDs is selected as a first model district of the province for salt iodization program. Objectives: To find out the proportion of the families using iodized salt, iodine contents of the salts used by the families, urinary iodine levels in school children and the effect on goiter prevalence in Swat selected as a model district in 1998. Subject and Methods: The study was conducted in 960 children of both sexes, age 8-10 years in primary schools of district Swat in the year 2000. A replicate model used for base line study in 1998 was adopted. The students were clinically examined for goiter using palpation method. 960 edible salt samples for its iodine content and 240 urine samples for iodine level were analysed. Results: The overall goiter prevalence was found to be 52 and 45% in boys and girls respectively. 23% salt samples were found un-iodized, while in 25.6% the iodine content was less than 7ppm. The results revealed 18% decrease in total goiter rate and 35% increase in the use of iodized salt from the base line survey conducted in 1998, in school children of district Swat. Conclusions: The study revealed that since the area of Swat is still highly endemic for Iodine Deficiency Disorders, sustained efforts are required to ensure 100% salt iodization. (author)

  4. Guidelines for using sensitivity analysis and auto-calibration tools for multi-gage or multi-step calibration in SWAT

    Science.gov (United States)

    Autocalibration of a water quality model such as SWAT (Soil and Water Assessment Tool) can be a powerful, labor-saving tool. When multi-gage or multi-pollutant calibration is desired, autocalibration is essential because the time involved in manual calibration becomes prohibitive. The ArcSWAT Interf...

  5. Hydrological Responses of Climate and Land Use/Cover Changes in Tao'er River Basin Based on the SWAT Model

    Science.gov (United States)

    Liu, J.; Kou, L.

    2015-12-01

    Abstract: The changes of both climate and land use/cover have some impact on the water resources. For Tao'er River Basin, these changes have a direct impact on the land use pattern adjustment, wetland protection, connection project between rivers and reservoirs, local social and economic development, etc. Therefore, studying the impact of climate and land use/cover changes is of great practical significance. The Soil and Water Assessment Tool (SWAT) is used as the research method. With historical actual measured runoff data and the yearly land use classification caught by satellite remote sensing maps, analyze the impact of climate change on the runoff of Tao'er River. And according to the land use/cover classification of 1990, 2000 and 2010, analyze the land use/cover change in the recent 30 years, the impact of the land use/cover change on the river runoff and the contribution coefficient of farmland, woodland, grassland and other major land-use types to the runoff. These studies can provide some references to the rational allocation of water resource and adjustment of land use structure in this area.

  6. Developing a Resource for Implementing ArcSWAT Using Global Datasets

    Science.gov (United States)

    Taggart, M.; Caraballo Álvarez, I. O.; Mueller, C.; Palacios, S. L.; Schmidt, C.; Milesi, C.; Palmer-Moloney, L. J.

    2015-12-01

    This project developed a comprehensive user manual outlining methods for adapting and implementing global datasets for use within ArcSWAT for international and worldwide applications. The Soil and Water Assessment Tool (SWAT) is a hydrologic model that looks at a number of hydrologic variables including runoff and the chemical makeup of water at a given location on the Earth's surface using Digital Elevation Models (DEM), land cover, soil, and weather data. However, the application of ArcSWAT for projects outside of the United States is challenging as there is no standard framework for inputting global datasets into ArcSWAT. This project aims to remove this obstacle by outlining methods for adapting and implementing these global datasets via the user manual. The manual takes the user through the processes of data conditioning while providing solutions and suggestions for common errors. The efficacy of the manual was explored using examples from watersheds located in Puerto Rico, Mexico and Western Africa. Each run explored the various options for setting up a ArcSWAT project as well as a range of satellite data products and soil databases. Future work will incorporate in-situ data for validation and calibration of the model and outline additional resources to assist future users in efficiently implementing the model for worldwide applications. The capacity to manage and monitor freshwater availability is of critical importance in both developed and developing countries. As populations grow and climate changes, both the quality and quantity of freshwater are affected resulting in negative impacts on the health of the surrounding population. The use of hydrologic models such as ArcSWAT can help stakeholders and decision makers understand the future impacts of these changes enabling informed and substantiated decisions.

  7. Application of the Soil and Water Assessment Tool (SWAT Model on a small tropical island (Great River Watershed, Jamaica as a tool in Integrated Watershed and Coastal Zone Management

    Directory of Open Access Journals (Sweden)

    Orville P. Grey

    2014-09-01

    Full Text Available The Great River Watershed, located in north-west Jamaica, is critical for development, particularly for housing, tourism, agriculture, and mining. It is a source of sediment and nutrient loading to the coastal environment including the Montego Bay Marine Park. We produced a modeling framework using the Soil and Water Assessment Tool (SWAT and GIS. The calculated model performance statistics for high flow discharge yielded a Nash-Sutcliffe Efficiency (NSE value of 0.68 and a R² value of 0.70 suggesting good measured and simulated (calibrated discharge correlation. Calibration and validation results for streamflow were similar to the observed streamflows. For the dry season the simulated urban landuse scenario predicted an increase in surface runoff in excess of 150%. During the wet season it is predicted to range from 98 to 234% presenting a significant risk of flooding, erosion and other environmental issues. The model should be used for the remaining 25 watersheds in Jamaica and elsewhere in the Caribbean. The models suggests that projected landuse changes will have serious impacts on available water (streamflow, stream health, potable water treatment, flooding and sensitive coastal ecosystems.

  8. Comparison of MODIS and SWAT evapotranspiration over a complex terrain at different spatial scales

    Science.gov (United States)

    Abiodun, Olanrewaju O.; Guan, Huade; Post, Vincent E. A.; Batelaan, Okke

    2018-05-01

    In most hydrological systems, evapotranspiration (ET) and precipitation are the largest components of the water balance, which are difficult to estimate, particularly over complex terrain. In recent decades, the advent of remotely sensed data based ET algorithms and distributed hydrological models has provided improved spatially upscaled ET estimates. However, information on the performance of these methods at various spatial scales is limited. This study compares the ET from the MODIS remotely sensed ET dataset (MOD16) with the ET estimates from a SWAT hydrological model on graduated spatial scales for the complex terrain of the Sixth Creek Catchment of the Western Mount Lofty Ranges, South Australia. ET from both models was further compared with the coarser-resolution AWRA-L model at catchment scale. The SWAT model analyses are performed on daily timescales with a 6-year calibration period (2000-2005) and 7-year validation period (2007-2013). Differences in ET estimation between the SWAT and MOD16 methods of up to 31, 19, 15, 11 and 9 % were observed at respectively 1, 4, 9, 16 and 25 km2 spatial resolutions. Based on the results of the study, a spatial scale of confidence of 4 km2 for catchment-scale evapotranspiration is suggested in complex terrain. Land cover differences, HRU parameterisation in AWRA-L and catchment-scale averaging of input climate data in the SWAT semi-distributed model were identified as the principal sources of weaker correlations at higher spatial resolution.

  9. Simulation on Change Law of Runoff, Sediment and Non-point Source Nitrogen and Phosphorus Discharge under Different Land uses Based on SWAT Model: A Case Study of Er hai Lake Small Watershed

    Science.gov (United States)

    Tong, Xiao Xia; Lai Cui, Yuan; Chen, Man Yu; Hu, Bo; Xu, Wen Sheng

    2018-05-01

    The Er yuan watershed of Er hai district is chosen as the research area, the law of runoff and sediment and non-point source nitrogen and phosphorus discharges under different land uses during 2001 to 2014 are simulated based on SWAT model. Results of simulation indicate that the order of total runoff yield of different land use type from high to low is grassland, paddy fields, dry land. Specifically, the order of surface runoff yield from high to low is paddy fields, dry land, grassland, the order of lateral runoff yield from high to low is paddy fields, dry land, grassland, the order of groundwater runoff yield from high to low is grassland, paddy fields, dry land. The orders of sediment and nitrogen and phosphorus yield per unit area of different land use type are the same, grassland> paddy fields> dry land. It can be seen, nitrogen and phosphorus discharges from paddy fields and dry land are the main sources of agricultural non-point pollution of the irrigated area. Therefore, reasonable field management measures which can decrease the discharge of nitrogen and phosphorus of paddy fields and dry land are the key to agricultural non-point source pollution prevention and control.

  10. Geostatistical methods applied to field model residuals

    DEFF Research Database (Denmark)

    Maule, Fox; Mosegaard, K.; Olsen, Nils

    consists of measurement errors and unmodelled signal), and is typically assumed to be uncorrelated and Gaussian distributed. We have applied geostatistical methods to analyse the residuals of the Oersted(09d/04) field model [http://www.dsri.dk/Oersted/Field_models/IGRF_2005_candidates/], which is based...

  11. Modeling discharge and water quality in a temporary river basin using SWAT model: A case-study on the Ardila river

    OpenAIRE

    Durão, Anabela; Serafim, António; Brito, David; Morais, Manuela

    2012-01-01

    Temporary rivers have a hydrologic variability, which are characterized by long drought periods and short floods events, that influences water quality. Analysis of river flow generated in the Ardila river basin (temporary regime) using precipitation data (from 1931 to 2003) from a weather station, located within the basin, at the Portuguese side (which represents only 22% of the study area) showed a discrepancy between the modeled and observed runoff since 1981. It was also revealed a satisfa...

  12. Characterizing snowmelt regime of the river swat - a case study

    International Nuclear Information System (INIS)

    Malik, M.A.

    2015-01-01

    Snowmelt generates 70 to 80% of runoff of Indus River and its tributaries. Forecasting snowmelt generated flow is important for water management, reservoir operation and channel diversion. River Swat being not direct contributor to the existing reservoirs remained out of focus for characterizing its snowmelt regime. Thirty years (1971-2000) data of upper Swat catchment above Kalam gauging station was acquired from WAPDA. Normal monthly values over the period and average monthly values of each year were determined for stream flow, precipitation and temperature together with average monthly values of weighted and maximum temperature. Snowmelt regime was ascertained from plot of normal values of flow, precipitation and temperature. Using temperature index approach, average monthly flow over the snowmelt months (April, May and June) in terms of mm depth over the catchment was regressed on all the temperature indices using exponential, power and third degree polynomial functions. Tmax was found the best index for snowmelt with R2 as 0.902 for the third degree polynomial function. Runoff coefficient (ROC) for the total precipitation was conceptualized and through iteration was found as T max 100. The optimized value of ROC was used to segregate rain induced and snowmelt induced runoff. The segregated snowmelt induced runoff was again regressed on Tmax using the same function which slightly improved R2 to 0.916. The model was tested for four years of data and forecasted flow was found reasonable in the context of simplicity of the approach. (author)

  13. The SWAT approach for pipeline watercourse crossings

    Energy Technology Data Exchange (ETDEWEB)

    Jasper, Steve [WorleyParsons Calgary, Pipeline Systems Business Unit, Calgary, AB (Canada)], email: steve.jasper@worleyparsons.com; Harris, Jason D. [Triton Environmental Consultants Ltd., Terrace, British Columbia (Canada)], email: jharris@triton-env.com; Doering, Raymond [Enbridge Northern Gateway Pipelines, Calgary, AB (Canada)], email: raymond.doering@enbridge.com

    2010-07-01

    In a pipeline project, watercourse crossings are an important environmental and technical challenge. In identifying the best crossing location and method, many factors must be taken into account such as fish habitat, access, geotechnical and hydrological issues. The aim of this paper is to present a program used in a major pipeline project to assess crossings of sensitive watercourses. This program was implemented in the Enbridge Northern Gateway project which extends from Bruderheim, Alberta, to Kitimat, British Columbia, crossing over 750 watercourses. A sensitive watercourse assessment (SWAT) team composed of a fisheries biologist, a pipeline watercourse construction specialist and other personnel carried out assessments on the 200 sensitive watercourses identified. This program led to recommendations to shift the crossing location at 40% of the sensitive sites. This project showed that setting up a SWAT team be helpful in choosing the best location, method and construction timing for a crossing.

  14. Applying the WEAP Model to Water Resource

    DEFF Research Database (Denmark)

    Gao, Jingjing; Christensen, Per; Li, Wei

    efficiency, treatment and reuse of water. The WEAP model was applied to the Ordos catchment where it was used for the first time in China. The changes in water resource utilization in Ordos basin were assessed with the model. It was found that the WEAP model is a useful tool for water resource assessment......Water resources assessment is a tool to provide decision makers with an appropriate basis to make informed judgments regarding the objectives and targets to be addressed during the Strategic Environmental Assessment (SEA) process. The study shows how water resources assessment can be applied in SEA...... in assessing the effects on water resources using a case study on a Coal Industry Development Plan in an arid region in North Western China. In the case the WEAP model (Water Evaluation And Planning System) were used to simulate various scenarios using a diversity of technological instruments like irrigation...

  15. Applied probability models with optimization applications

    CERN Document Server

    Ross, Sheldon M

    1992-01-01

    Concise advanced-level introduction to stochastic processes that frequently arise in applied probability. Largely self-contained text covers Poisson process, renewal theory, Markov chains, inventory theory, Brownian motion and continuous time optimization models, much more. Problems and references at chapter ends. ""Excellent introduction."" - Journal of the American Statistical Association. Bibliography. 1970 edition.

  16. Applied Integer Programming Modeling and Solution

    CERN Document Server

    Chen, Der-San; Dang, Yu

    2011-01-01

    An accessible treatment of the modeling and solution of integer programming problems, featuring modern applications and software In order to fully comprehend the algorithms associated with integer programming, it is important to understand not only how algorithms work, but also why they work. Applied Integer Programming features a unique emphasis on this point, focusing on problem modeling and solution using commercial software. Taking an application-oriented approach, this book addresses the art and science of mathematical modeling related to the mixed integer programming (MIP) framework and

  17. Applied research in uncertainty modeling and analysis

    CERN Document Server

    Ayyub, Bilal

    2005-01-01

    Uncertainty has been a concern to engineers, managers, and scientists for many years. For a long time uncertainty has been considered synonymous with random, stochastic, statistic, or probabilistic. Since the early sixties views on uncertainty have become more heterogeneous. In the past forty years numerous tools that model uncertainty, above and beyond statistics, have been proposed by several engineers and scientists. The tool/method to model uncertainty in a specific context should really be chosen by considering the features of the phenomenon under consideration, not independent of what is known about the system and what causes uncertainty. In this fascinating overview of the field, the authors provide broad coverage of uncertainty analysis/modeling and its application. Applied Research in Uncertainty Modeling and Analysis presents the perspectives of various researchers and practitioners on uncertainty analysis and modeling outside their own fields and domain expertise. Rather than focusing explicitly on...

  18. Applied Mathematics, Modelling and Computational Science

    CERN Document Server

    Kotsireas, Ilias; Makarov, Roman; Melnik, Roderick; Shodiev, Hasan

    2015-01-01

    The Applied Mathematics, Modelling, and Computational Science (AMMCS) conference aims to promote interdisciplinary research and collaboration. The contributions in this volume cover the latest research in mathematical and computational sciences, modeling, and simulation as well as their applications in natural and social sciences, engineering and technology, industry, and finance. The 2013 conference, the second in a series of AMMCS meetings, was held August 26–30 and organized in cooperation with AIMS and SIAM, with support from the Fields Institute in Toronto, and Wilfrid Laurier University. There were many young scientists at AMMCS-2013, both as presenters and as organizers. This proceedings contains refereed papers contributed by the participants of the AMMCS-2013 after the conference. This volume is suitable for researchers and graduate students, mathematicians and engineers, industrialists, and anyone who would like to delve into the interdisciplinary research of applied and computational mathematics ...

  19. Applying incentive sensitization models to behavioral addiction

    DEFF Research Database (Denmark)

    Rømer Thomsen, Kristine; Fjorback, Lone; Møller, Arne

    2014-01-01

    The incentive sensitization theory is a promising model for understanding the mechanisms underlying drug addiction, and has received support in animal and human studies. So far the theory has not been applied to the case of behavioral addictions like Gambling Disorder, despite sharing clinical...... symptoms and underlying neurobiology. We examine the relevance of this theory for Gambling Disorder and point to predictions for future studies. The theory promises a significant contribution to the understanding of behavioral addiction and opens new avenues for treatment....

  20. Estimating shallow groundwater recharge in the headwaters of the Liverpool Plains using SWAT

    OpenAIRE

    Sun, H.; Cornish, P.S.

    2005-01-01

    Metadata only record A physically based catchment model (SWAT) was used for recharge estimation in the headwaters of the Liverpool Plains in NSW, Australia. The study used water balance modelling at the catchment scale to derive parameters for long-term recharge estimation. The derived parameters were further assessed at a subcatchment scale. Modelling results suggest that recharge occurs only in wet years, and is dominated by a few significant years or periods. The results were matched by...

  1. Applied Regression Modeling A Business Approach

    CERN Document Server

    Pardoe, Iain

    2012-01-01

    An applied and concise treatment of statistical regression techniques for business students and professionals who have little or no background in calculusRegression analysis is an invaluable statistical methodology in business settings and is vital to model the relationship between a response variable and one or more predictor variables, as well as the prediction of a response value given values of the predictors. In view of the inherent uncertainty of business processes, such as the volatility of consumer spending and the presence of market uncertainty, business professionals use regression a

  2. Terahertz spectroscopy applied to food model systems

    DEFF Research Database (Denmark)

    Møller, Uffe

    Water plays a crucial role in the quality of food. Apart from the natural water content of a food product, the state of that water is very important. Water can be found integrated into the biological material or it can be added during production of the product. Currently it is difficult...... to differentiate between these types of water in subsequent quality controls. This thesis describes terahertz time-domain spectroscopy applied on aqueous food model systems, with particular focus on ethanol-water mixtures and confined water pools in inverse micelles....

  3. Hydrological effects of the increased CO2 and climate change in the Upper Mississippi River Basin using a modified SWAT

    Science.gov (United States)

    Wu, Y.; Liu, S.; Abdul-Aziz, O. I.

    2012-01-01

    Increased atmospheric CO2 concentration and climate change may significantly impact the hydrological and meteorological processes of a watershed system. Quantifying and understanding hydrological responses to elevated ambient CO2 and climate change is, therefore, critical for formulating adaptive strategies for an appropriate management of water resources. In this study, the Soil and Water Assessment Tool (SWAT) model was applied to assess the effects of increased CO2 concentration and climate change in the Upper Mississippi River Basin (UMRB). The standard SWAT model was modified to represent more mechanistic vegetation type specific responses of stomatal conductance reduction and leaf area increase to elevated CO2 based on physiological studies. For estimating the historical impacts of increased CO2 in the recent past decades, the incremental (i.e., dynamic) rises of CO2 concentration at a monthly time-scale were also introduced into the model. Our study results indicated that about 1–4% of the streamflow in the UMRB during 1986 through 2008 could be attributed to the elevated CO2 concentration. In addition to evaluating a range of future climate sensitivity scenarios, the climate projections by four General Circulation Models (GCMs) under different greenhouse gas emission scenarios were used to predict the hydrological effects in the late twenty-first century (2071–2100). Our simulations demonstrated that the water yield would increase in spring and substantially decrease in summer, while soil moisture would rise in spring and decline in summer. Such an uneven distribution of water with higher variability compared to the baseline level (1961–1990) may cause an increased risk of both flooding and drought events in the basin.

  4. Soil Water and Temperature System (SWATS) Instrument Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Cook, David R. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-04-01

    The soil water and temperature system (SWATS) provides vertical profiles of soil temperature, soil-water potential, and soil moisture as a function of depth below the ground surface at hourly intervals. The temperature profiles are measured directly by in situ sensors at the Central Facility and many of the extended facilities of the U.S. Department of Energy (DOE)’s Atmospheric Radiation Measurement (ARM) Climate Research Facility Southern Great Plains (SGP) site. The soil-water potential and soil moisture profiles are derived from measurements of soil temperature rise in response to small inputs of heat. Atmospheric scientists use the data in climate models to determine boundary conditions and to estimate the surface energy flux. The data are also useful to hydrologists, soil scientists, and agricultural scientists for determining the state of the soil.

  5. Analyses of PWR spent fuel composition using SCALE and SWAT code systems to find correction factors for criticality safety applications adopting burnup credit

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hee Sung; Suyama, Kenya; Mochizuki, Hiroki; Okuno, Hiroshi; Nomura, Yasushi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-01-01

    The isotopic composition calculations were performed for 26 spent fuel samples from the Obrigheim PWR reactor and 55 spent fuel samples from 7 PWR reactors using the SAS2H module of the SCALE4.4 code system with 27, 44 and 238 group cross-section libraries and the SWAT code system with the 107 group cross-section library. For the analyses of samples from the Obrigheim PWR reactor, geometrical models were constructed for each of SCALE4.4/SAS2H and SWAT. For the analyses of samples from 7 PWR reactors, the geometrical model already adopted in the SCALE/SAS2H was directly converted to the model of SWAT. The four kinds of calculation results were compared with the measured data. For convenience, the ratio of the measured to calculated values was used as a parameter. When the ratio is less than unity, the calculation overestimates the measurement, and the ratio becomes closer to unity, they have a better agreement. For many important nuclides for burnup credit criticality safety evaluation, the four methods applied in this study showed good coincidence with measurements in general. More precise observations showed, however: (1) Less unity ratios were found for Pu-239 and -241 for selected 16 samples out of the 26 samples from the Obrigheim reactor (10 samples were deselected because their burnups were measured with Cs-137 non-destructive method, less reliable than Nd-148 method the rest 16 samples were measured with); (2) Larger than unity ratios were found for Am-241 and Cm-242 for both the 16 and 55 samples; (3) Larger than unity ratios were found for Sm-149 for the 55 samples; (4) SWAT was generally accompanied by larger ratios than those of SAS2H with some exceptions. Based on the measured-to-calculated ratios for 71 samples of a combined set in which 16 selected samples and 55 samples were included, the correction factors that should be multiplied to the calculated isotopic compositions were generated for a conservative estimate of the neutron multiplication factor

  6. Commercial Consolidation Model Applied to Transport Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Guilherme de Aragão, J.J.; Santos Fontes Pereira, L. dos; Yamashita, Y.

    2016-07-01

    Since the 1990s, transport concessions, including public-private partnerships (PPPs), have been increasingly adopted by governments as an alternative for financing and operations in public investments, especially in transport infrastructure. The advantage pointed out by proponents of these models lies in merging the expertise and capital of the private sector to the public interest. Several arrangements are possible and have been employed in different cases. After the duration of the first PPP contracts in transportation, many authors have analyzed the success and failure factors of partnerships. The occurrence of failures in some stages of the process can greatly encumber the public administration, incurring losses to the fiscal responsibility of the competent bodies. This article aims to propose a new commercial consolidation model applied to transport infrastructure to ensure fiscal sustainability and overcome the weaknesses of current models. Initially, a systematic review of the literature covering studies on transport concessions between 1990 and 2015 is offered, where the different approaches between various countries are compared and the critical success factors indicated in the studies are identified. In the subsequent part of the paper, an approach for the commercial consolidation of the infrastructure concessions is presented, where the concessionary is paid following a finalistic performance model, which includes the overall fiscal balance of regional growth. Finally, the papers analyses the usefulness of the model in coping with the critical success factors explained before. (Author)

  7. Modifying the Soil and Water Assessment Tool to simulate cropland carbon flux: Model development and initial evaluation

    International Nuclear Information System (INIS)

    Zhang, Xuesong; Izaurralde, R. César; Arnold, Jeffrey G.; Williams, Jimmy R.; Srinivasan, Raghavan

    2013-01-01

    Climate change is one of the most compelling modern issues and has important implications for almost every aspect of natural and human systems. The Soil and Water Assessment Tool (SWAT) model has been applied worldwide to support sustainable land and water management in a changing climate. However, the inadequacies of the existing carbon algorithm in SWAT limit its application in assessing impacts of human activities on CO 2 emission, one important source of greenhouse gasses (GHGs) that traps heat in the earth system and results in global warming. In this research, we incorporate a revised version of the CENTURY carbon model into SWAT to describe dynamics of soil organic matter (SOM)-residue and simulate land–atmosphere carbon exchange. We test this new SWAT-C model with daily eddy covariance (EC) observations of net ecosystem exchange (NEE) and evapotranspiration (ET) and annual crop yield at six sites across the U.S. Midwest. Results show that SWAT-C simulates well multi-year average NEE and ET across the spatially distributed sites and capture the majority of temporal variation of these two variables at a daily time scale at each site. Our analyses also reveal that performance of SWAT-C is influenced by multiple factors, such as crop management practices (irrigated vs. rainfed), completeness and accuracy of input data, crop species, and initialization of state variables. Overall, the new SWAT-C demonstrates favorable performance for simulating land–atmosphere carbon exchange across agricultural sites with different soils, climate, and management practices. SWAT-C is expected to serve as a useful tool for including carbon flux into consideration in sustainable watershed management under a changing climate. We also note that extensive assessment of SWAT-C with field observations is required for further improving the model and understanding potential uncertainties of applying it across large regions with complex landscapes. - Highlights: • Expanding the SWAT

  8. Modifying the Soil and Water Assessment Tool to simulate cropland carbon flux: Model development and initial evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xuesong; Izaurralde, R. César [Joint Global Change Research Institute, Pacific Northwest National Laboratory and University of Maryland, College Park, MD 20740 (United States); Arnold, Jeffrey G. [Grassland, Soil and Water Research Laboratory USDA-ARS, Temple, TX 76502 (United States); Williams, Jimmy R. [Blackland Research and Extension Center, AgriLIFE Research, 720 E. Blackland Road, Temple, TX 76502 (United States); Srinivasan, Raghavan [Spatial Sciences Laboratory in the Department of Ecosystem Science and Management, Texas A and M University, College Stations, TX 77845 (United States)

    2013-10-01

    Climate change is one of the most compelling modern issues and has important implications for almost every aspect of natural and human systems. The Soil and Water Assessment Tool (SWAT) model has been applied worldwide to support sustainable land and water management in a changing climate. However, the inadequacies of the existing carbon algorithm in SWAT limit its application in assessing impacts of human activities on CO{sub 2} emission, one important source of greenhouse gasses (GHGs) that traps heat in the earth system and results in global warming. In this research, we incorporate a revised version of the CENTURY carbon model into SWAT to describe dynamics of soil organic matter (SOM)-residue and simulate land–atmosphere carbon exchange. We test this new SWAT-C model with daily eddy covariance (EC) observations of net ecosystem exchange (NEE) and evapotranspiration (ET) and annual crop yield at six sites across the U.S. Midwest. Results show that SWAT-C simulates well multi-year average NEE and ET across the spatially distributed sites and capture the majority of temporal variation of these two variables at a daily time scale at each site. Our analyses also reveal that performance of SWAT-C is influenced by multiple factors, such as crop management practices (irrigated vs. rainfed), completeness and accuracy of input data, crop species, and initialization of state variables. Overall, the new SWAT-C demonstrates favorable performance for simulating land–atmosphere carbon exchange across agricultural sites with different soils, climate, and management practices. SWAT-C is expected to serve as a useful tool for including carbon flux into consideration in sustainable watershed management under a changing climate. We also note that extensive assessment of SWAT-C with field observations is required for further improving the model and understanding potential uncertainties of applying it across large regions with complex landscapes. - Highlights: • Expanding the

  9. Development of a station based climate database for SWAT and APEX assessments in the U.S.

    Science.gov (United States)

    Water quality simulation models such as the Soil and Water Assessment Tool (SWAT) and Agricultural Policy EXtender (APEX) are widely used in the U.S. These models require large amounts of spatial and tabular data to simulate the natural world. Accurate and seamless daily climatic data are critical...

  10. Geomorphological hazards in Swat valley, Pakistan

    International Nuclear Information System (INIS)

    Usman, A.

    1999-01-01

    This study attempts to describe, interpret and analyze, in depth, the varied geomorphological hazards and their impacts prevailing in the swat valley locate in the northern hilly and mountainous regions of Pakistan. The hills and mountains re zones of high geomorphological activity with rapid rates of weathering, active tectonic activities, abundant precipitation, rapid runoff and heavy sediment transport. Due to the varied topography, lithology, steep slope, erodible soil, heavy winter snowfall and intensive rainfall in the spring and summer seasons, several kinds of geomorphological hazards, such as geomorphic gravitational hazards, Fluvial hazards, Glacial hazards, Geo tectonic hazards, are occurring frequently in swat valley. Amongst them, geomorphic gravitational hazards, such as rock fall rock slide, debris slide mud flow avalanches, are major hazards in mountains and hills while fluvial hazards and sedimentation are mainly confined to the alluvial plain and lowlands of the valley. The Getechtonic hazards, on the other hand, have wide spread distribution in the valley the magnitude and occurrence of each king of hazard is thus, varied according to intensity of process and physical geographic environment. This paper discusses the type distribution and damage due to the various geomorphological hazards and their reduction treatments. The study would to be of particular importance and interest to both natural and social scientists, as well as planner, environmentalists and decision-makers for successful developmental interventions in the region. (author)

  11. Comparison of MODIS and SWAT evapotranspiration over a complex terrain at different spatial scales

    Directory of Open Access Journals (Sweden)

    O. O. Abiodun

    2018-05-01

    Full Text Available In most hydrological systems, evapotranspiration (ET and precipitation are the largest components of the water balance, which are difficult to estimate, particularly over complex terrain. In recent decades, the advent of remotely sensed data based ET algorithms and distributed hydrological models has provided improved spatially upscaled ET estimates. However, information on the performance of these methods at various spatial scales is limited. This study compares the ET from the MODIS remotely sensed ET dataset (MOD16 with the ET estimates from a SWAT hydrological model on graduated spatial scales for the complex terrain of the Sixth Creek Catchment of the Western Mount Lofty Ranges, South Australia. ET from both models was further compared with the coarser-resolution AWRA-L model at catchment scale. The SWAT model analyses are performed on daily timescales with a 6-year calibration period (2000–2005 and 7-year validation period (2007–2013. Differences in ET estimation between the SWAT and MOD16 methods of up to 31, 19, 15, 11 and 9 % were observed at respectively 1, 4, 9, 16 and 25 km2 spatial resolutions. Based on the results of the study, a spatial scale of confidence of 4 km2 for catchment-scale evapotranspiration is suggested in complex terrain. Land cover differences, HRU parameterisation in AWRA-L and catchment-scale averaging of input climate data in the SWAT semi-distributed model were identified as the principal sources of weaker correlations at higher spatial resolution.

  12. [Nitrogen non-point source pollution identification based on ArcSWAT in Changle River].

    Science.gov (United States)

    Deng, Ou-Ping; Sun, Si-Yang; Lü, Jun

    2013-04-01

    The ArcSWAT (Soil and Water Assessment Tool) model was adopted for Non-point source (NPS) nitrogen pollution modeling and nitrogen source apportionment for the Changle River watershed, a typical agricultural watershed in Southeast China. Water quality and hydrological parameters were monitored, and the watershed natural conditions (including soil, climate, land use, etc) and pollution sources information were also investigated and collected for SWAT database. The ArcSWAT model was established in the Changle River after the calibrating and validating procedures of the model parameters. Based on the validated SWAT model, the contributions of different nitrogen sources to river TN loading were quantified, and spatial-temporal distributions of NPS nitrogen export to rivers were addressed. The results showed that in the Changle River watershed, Nitrogen fertilizer, nitrogen air deposition and nitrogen soil pool were the prominent pollution sources, which contributed 35%, 32% and 25% to the river TN loading, respectively. There were spatial-temporal variations in the critical sources for NPS TN export to the river. Natural sources, such as soil nitrogen pool and atmospheric nitrogen deposition, should be targeted as the critical sources for river TN pollution during the rainy seasons. Chemical nitrogen fertilizer application should be targeted as the critical sources for river TN pollution during the crop growing season. Chemical nitrogen fertilizer application, soil nitrogen pool and atmospheric nitrogen deposition were the main sources for TN exported from the garden plot, forest and residential land, respectively. However, they were the main sources for TN exported both from the upland and paddy field. These results revealed that NPS pollution controlling rules should focus on the spatio-temporal distribution of NPS pollution sources.

  13. FEST-C 1.3 & 2.0 for CMAQ Bi-directional NH3, Crop Production, and SWAT Modeling

    Science.gov (United States)

    The Fertilizer Emission Scenario Tool for CMAQ (FEST-C) is developed in a Linux environment, a festc JAVA interface that integrates 14 tools and scenario management options facilitating land use/crop data processing for the Community Multiscale Air Quality (CMAQ) modeling system ...

  14. Using SWAT and Fuzzy TOPSIS to Assess the Impact of Climate Change in the Headwaters of the Segura River Basin (SE Spain

    Directory of Open Access Journals (Sweden)

    Javier Senent-Aparicio

    2017-02-01

    Full Text Available The Segura River Basin is one of the most water-stressed basins in Mediterranean Europe. If we add to the actual situation that most climate change projections forecast important decreases in water resource availability in the Mediterranean region, the situation will become totally unsustainable. This study assessed the impact of climate change in the headwaters of the Segura River Basin using the Soil and Water Assessment Tool (SWAT with bias-corrected precipitation and temperature data from two Regional Climate Models (RCMs for the medium term (2041–2070 and the long term (2071–2100 under two emission scenarios (RCP4.5 and RCP8.5. Bias correction was performed using the distribution mapping approach. The fuzzy TOPSIS technique was applied to rank a set of nine GCM–RCM combinations, choosing the climate models with a higher relative closeness. The study results show that the SWAT performed satisfactorily for both calibration (NSE = 0.80 and validation (NSE = 0.77 periods. Comparing the long-term and baseline (1971–2000 periods, precipitation showed a negative trend between 6% and 32%, whereas projected annual mean temperatures demonstrated an estimated increase of 1.5–3.3 °C. Water resources were estimated to experience a decrease of 2%–54%. These findings provide local water management authorities with very useful information in the face of climate change.

  15. Modelování průtoků a vybraných parametrů jakosti vod na povodí Jenínského potoka modelem SWAT

    OpenAIRE

    HOMOLKA, Jan

    2014-01-01

    The thesis continues with the bachelor thesis which had dealt with preparation bases for simulation draining and carrying materials in SWAT model. Simulation should have been realized within basin of the Jenín stream, which watershed is 4,65 km2 large. SWAT model is primary developed for the larger watersheds where simulated values doesn't attain tolerances. Because of this is thesis focused on the methodic of simulation itself, discussion of the problem when is SWAT model almost useless for ...

  16. Relationships between water table and model simulated ET

    Science.gov (United States)

    Prem B. Parajuli; Gretchen F. Sassenrath; Ying Ouyang

    2013-01-01

    This research was conducted to develop relationships among evapotranspiration (ET), percolation (PERC), groundwater discharge to the stream (GWQ), and water table fluctuations through a modeling approach. The Soil and Water Assessment Tool (SWAT) hydrologic and crop models were applied in the Big Sunflower River watershed (BSRW; 7660 km2) within the Yazoo River Basin...

  17. Parallelization of a hydrological model using the message passing interface

    Science.gov (United States)

    Wu, Yiping; Li, Tiejian; Sun, Liqun; Chen, Ji

    2013-01-01

    With the increasing knowledge about the natural processes, hydrological models such as the Soil and Water Assessment Tool (SWAT) are becoming larger and more complex with increasing computation time. Additionally, other procedures such as model calibration, which may require thousands of model iterations, can increase running time and thus further reduce rapid modeling and analysis. Using the widely-applied SWAT as an example, this study demonstrates how to parallelize a serial hydrological model in a Windows® environment using a parallel programing technology—Message Passing Interface (MPI). With a case study, we derived the optimal values for the two parameters (the number of processes and the corresponding percentage of work to be distributed to the master process) of the parallel SWAT (P-SWAT) on an ordinary personal computer and a work station. Our study indicates that model execution time can be reduced by 42%–70% (or a speedup of 1.74–3.36) using multiple processes (two to five) with a proper task-distribution scheme (between the master and slave processes). Although the computation time cost becomes lower with an increasing number of processes (from two to five), this enhancement becomes less due to the accompanied increase in demand for message passing procedures between the master and all slave processes. Our case study demonstrates that the P-SWAT with a five-process run may reach the maximum speedup, and the performance can be quite stable (fairly independent of a project size). Overall, the P-SWAT can help reduce the computation time substantially for an individual model run, manual and automatic calibration procedures, and optimization of best management practices. In particular, the parallelization method we used and the scheme for deriving the optimal parameters in this study can be valuable and easily applied to other hydrological or environmental models.

  18. Potensi bambu swat (gigantochloa verticillata sebagai material karbon aktif untuk adsorbed natural gas (ANG

    Directory of Open Access Journals (Sweden)

    Dewa Ngakan Ketut Putra Negara

    2017-03-01

    Full Text Available Abstrak: Bambu merupakan material biomassa yang banyak diteliti, diproduksi sebagai karbon aktif dan diaplikasikan di berbagaibidang kehidupan. Namun sangat sedikit bahkan hampir tidak ditemukan referensi yang membahas kegunaan karbonaktif dari bambusebagai adsorbent untuk Adsorbed Natural Gas (ANG. Penelitian ini difokuskan untukmengkarakterisasai dan menevaluasi potensi bambu swat (Gigantochloa verticillata sebagai material dasar karbon aktifuntuk aplikasi ANG. Pengujian yang dilakukan meliputi uji proximate, uji ultimate, uji komposisi kimia dan pengamatanstruktur mikro. Hasil penelitian menunjukkan bahwa bambuswat memiliki kandungan lignin 22,9920%, selulosa44,2247%, volatile 88’32%, carbon 43,42%,ash 1,83%, silica (1,8664% dan nitrogen 1,7065%. Bambu swat memilikiikatan pembuluh yang terdiri atas satu ikatan pembuluh (xilem dan floem dan dua ikatan serat yang terletak di sebelahdalam dan luar dari ikatan pembuluh.Secara umum dapat dikatakan bahwa bamboo jenis ini memiliki kandungansellulosa, volatile dan karbon yang cukup tinggi serta ash, silica, hydrogen dan nitrogen yang rendah sehinggabambuswat sangat berpotensi digunakan sebagai material sumber karbon aktif.Kata kunci: Karbon aktif, bambu swat, ANG, lignin, sellulosa, analisa ultimate dan proximates Abstract: Bamboo is a biomass material widely researched, produced as activated carbon and applied in various life fields.However, very little or almost no references were found with regard to utilization of bamboo activated carbon asadsorbent for Adsorbed Natural Gas (ANG. This study is concerned to characterize and evaluate potency of bambooswat (Gigantochloa verticillata as aprecursor of activated carbon for ANG application. Examinations conducted wereproximate, ultimate, chemical composisition tests and microstructure observation. The results showed that bambooswathave a lignin content 22.9920%, cellulose 44.2247%, volatile 88.32%, carbon 43.42%, ash 1.83%, silica 1.8664% andnitrogen

  19. Water quality modelling in the San Antonio River Basin driven by radar rainfall data

    Directory of Open Access Journals (Sweden)

    Almoutaz Elhassan

    2016-05-01

    Full Text Available Continuous monitoring of stream water quality is needed as it has significant impacts on human and ecological health and well-being. Estimating water quality between sampling dates requires model simulation based on the available geospatial and water quality data for a given watershed. Models such as the Soil and Water Assessment Tool (SWAT can be used to estimate the missing water quality data. In this study, SWAT was used to estimate water quality at a monitoring station near the outlet of the San Antonio River. Precipitation data from both rain gauges and weather radar were used to force the SWAT simulations. Virtual rain gauges which were based on weather radar data were created in the approximate centres of the 163 sub-watersheds of the San Antonio River Basin for SWAT simulations. This method was first tested in a smaller watershed in the middle of the Guadalupe River Basin resulting in increased model efficiency in simulating surface run-off. The method was then applied to the San Antonio River watershed and yielded good simulations for surface run-off (R2 = 0.7, nitrate (R2 = 0.6 and phosphate (R2 = 0.5 at the watershed outlet (Goliad, TX – USGS (United States Geological Survey gauge as compared to observed data. The study showed that the proper use of weather radar precipitation in SWAT model simulations improves the estimation of missing water quality data.

  20. Mathematical Modeling Applied to Maritime Security

    OpenAIRE

    Center for Homeland Defense and Security

    2010-01-01

    Center for Homeland Defense and Security, OUT OF THE CLASSROOM Download the paper: Layered Defense: Modeling Terrorist Transfer Threat Networks and Optimizing Network Risk Reduction” Students in Ted Lewis’ Critical Infrastructure Protection course are taught how mathematic modeling can provide...

  1. Applying Modeling Tools to Ground System Procedures

    Science.gov (United States)

    Di Pasquale, Peter

    2012-01-01

    As part of a long-term effort to revitalize the Ground Systems (GS) Engineering Section practices, Systems Modeling Language (SysML) and Business Process Model and Notation (BPMN) have been used to model existing GS products and the procedures GS engineers use to produce them.

  2. SWAT use of gridded observations for simulating runoff - a Vietnam river basin study

    Science.gov (United States)

    Vu, M. T.; Raghavan, S. V.; Liong, S. Y.

    2012-08-01

    Many research studies that focus on basin hydrology have applied the SWAT model using station data to simulate runoff. But over regions lacking robust station data, there is a problem of applying the model to study the hydrological responses. For some countries and remote areas, the rainfall data availability might be a constraint due to many different reasons such as lacking of technology, war time and financial limitation that lead to difficulty in constructing the runoff data. To overcome such a limitation, this research study uses some of the available globally gridded high resolution precipitation datasets to simulate runoff. Five popular gridded observation precipitation datasets: (1) Asian Precipitation Highly Resolved Observational Data Integration Towards the Evaluation of Water Resources (APHRODITE), (2) Tropical Rainfall Measuring Mission (TRMM), (3) Precipitation Estimation from Remote Sensing Information using Artificial Neural Network (PERSIANN), (4) Global Precipitation Climatology Project (GPCP), (5) a modified version of Global Historical Climatology Network (GHCN2) and one reanalysis dataset, National Centers for Environment Prediction/National Center for Atmospheric Research (NCEP/NCAR) are used to simulate runoff over the Dak Bla river (a small tributary of the Mekong River) in Vietnam. Wherever possible, available station data are also used for comparison. Bilinear interpolation of these gridded datasets is used to input the precipitation data at the closest grid points to the station locations. Sensitivity Analysis and Auto-calibration are performed for the SWAT model. The Nash-Sutcliffe Efficiency (NSE) and Coefficient of Determination (R2) indices are used to benchmark the model performance. Results indicate that the APHRODITE dataset performed very well on a daily scale simulation of discharge having a good NSE of 0.54 and R2 of 0.55, when compared to the discharge simulation using station data (0.68 and 0.71). The GPCP proved to be the

  3. SWAT use of gridded observations for simulating runoff – a Vietnam river basin study

    Directory of Open Access Journals (Sweden)

    M. T. Vu

    2012-08-01

    Full Text Available Many research studies that focus on basin hydrology have applied the SWAT model using station data to simulate runoff. But over regions lacking robust station data, there is a problem of applying the model to study the hydrological responses. For some countries and remote areas, the rainfall data availability might be a constraint due to many different reasons such as lacking of technology, war time and financial limitation that lead to difficulty in constructing the runoff data. To overcome such a limitation, this research study uses some of the available globally gridded high resolution precipitation datasets to simulate runoff. Five popular gridded observation precipitation datasets: (1 Asian Precipitation Highly Resolved Observational Data Integration Towards the Evaluation of Water Resources (APHRODITE, (2 Tropical Rainfall Measuring Mission (TRMM, (3 Precipitation Estimation from Remote Sensing Information using Artificial Neural Network (PERSIANN, (4 Global Precipitation Climatology Project (GPCP, (5 a modified version of Global Historical Climatology Network (GHCN2 and one reanalysis dataset, National Centers for Environment Prediction/National Center for Atmospheric Research (NCEP/NCAR are used to simulate runoff over the Dak Bla river (a small tributary of the Mekong River in Vietnam. Wherever possible, available station data are also used for comparison. Bilinear interpolation of these gridded datasets is used to input the precipitation data at the closest grid points to the station locations. Sensitivity Analysis and Auto-calibration are performed for the SWAT model. The Nash-Sutcliffe Efficiency (NSE and Coefficient of Determination (R2 indices are used to benchmark the model performance. Results indicate that the APHRODITE dataset performed very well on a daily scale simulation of discharge having a good NSE of 0.54 and R2 of 0.55, when compared to the discharge simulation using station data (0

  4. Applied Geography Internships: Operational Canadian Models.

    Science.gov (United States)

    Foster, L. T.

    1982-01-01

    Anxious to maintain student enrollments, geography departments have placed greater emphasis on the applied nature of the discipline. Described are (1) the advantages of internships in college geography curricula that enable students to gain firsthand knowledge about the usefulness of geography in real world situations and (2) operational models…

  5. Applied Creativity: The Creative Marketing Breakthrough Model

    Science.gov (United States)

    Titus, Philip A.

    2007-01-01

    Despite the increasing importance of personal creativity in today's business environment, few conceptual creativity frameworks have been presented in the marketing education literature. The purpose of this article is to advance the integration of creativity instruction into marketing classrooms by presenting an applied creative marketing…

  6. Applying Olap Model On Public Finance Management

    OpenAIRE

    Dorde Pavlovic; Branko Gledovic

    2011-01-01

    Budget control is derivate from one of the main functions of budget, that aims that the budget is control instrument of acquiring and pending of budget needs. OLAP model represents an instrument that finds its place in the budget planning process, executive phases of budget, accountancy, etc. There is a direct correlation between the OLAP model and public finance management process.

  7. Applying the Sport Education Model to Tennis

    Science.gov (United States)

    Ayvazo, Shiri

    2009-01-01

    The physical education field abounds with theoretically sound curricular approaches such as fitness education, skill theme approach, tactical approach, and sport education. In an era that emphasizes authentic sport experiences, the Sport Education Model includes unique features that sets it apart from other curricular models and can be a valuable…

  8. Utilization of Electronic Learning System in Swat Rural Areas

    Directory of Open Access Journals (Sweden)

    Nazir Ahmed Sangi

    2017-12-01

    Full Text Available As developments in electronic technologies i.e. personal computers, laptops, tablets, mobiles and wearable devices, the way of learning is also changing. Therefore, utilization of Information and Communication Technology (ICT has great important role in schools and colleges. ICT is using by students, teachers and societies in District Swat, KP, Pakistan in the form of mobiles internet (for social contact and chat, computers internet (for knowledge exploration and entertainment and multimedia (for teaching and learning. One of the difficulties involved in rural areas’ students of District Swat is that they cannot join class rooms due to their poor livelihood condition and far away from schools and colleges. Especially most of the females of rural areas of Swat do not come to schools and colleges for their family tradition and culture. Various questions were examined in every aspect of educational technologies in this study. We surveyed 50 responded randomly at District Swat from different schools and colleges and discovered that the responded were generally positive and have great interest about e-learning in Swat. The use of proposed electronic system for the learning, the literacy rate will increase in rural areas and students will achieve their individual goals.

  9. Applied modelling and computing in social science

    CERN Document Server

    Povh, Janez

    2015-01-01

    In social science outstanding results are yielded by advanced simulation methods, based on state of the art software technologies and an appropriate combination of qualitative and quantitative methods. This book presents examples of successful applications of modelling and computing in social science: business and logistic process simulation and optimization, deeper knowledge extractions from big data, better understanding and predicting of social behaviour and modelling health and environment changes.

  10. Private healthcare quality: applying a SERVQUAL model.

    Science.gov (United States)

    Butt, Mohsin Muhammad; de Run, Ernest Cyril

    2010-01-01

    This paper seeks to develop and test the SERVQUAL model scale for measuring Malaysian private health service quality. The study consists of 340 randomly selected participants visiting a private healthcare facility during a three-month data collection period. Data were analyzed using means, correlations, principal component and confirmatory factor analysis to establish the modified SERVQUAL scale's reliability, underlying dimensionality and convergent, discriminant validity. Results indicate a moderate negative quality gap for overall Malaysian private healthcare service quality. Results also indicate a moderate negative quality gap on each service quality scale dimension. However, scale development analysis yielded excellent results, which can be used in wider healthcare policy and practice. Respondents were skewed towards a younger population, causing concern that the results might not represent all Malaysian age groups. The study's major contribution is that it offers a way to assess private healthcare service quality. Second, it successfully develops a scale that can be used to measure health service quality in Malaysian contexts.

  11. Use of Decision Tables to Simulate Management in SWAT+

    Directory of Open Access Journals (Sweden)

    Jeffrey G. Arnold

    2018-05-01

    Full Text Available Decision tables have been used for many years in data processing and business applications to simulate complex rule sets. Several computer languages have been developed based on rule systems and they are easily programmed in several current languages. Land management and river–reservoir models simulate complex land management operations and reservoir management in highly regulated river systems. Decision tables are a precise yet compact way to model the rule sets and corresponding actions found in these models. In this study, we discuss the suitability of decision tables to simulate management in the river basin scale Soil and Water Assessment Tool (SWAT+ model. Decision tables are developed to simulate automated irrigation and reservoir releases. A simple auto irrigation application of decision tables was developed using plant water stress as a condition for irrigating corn in Texas. Sensitivity of the water stress trigger and irrigation application amounts were shown on soil moisture and corn yields. In addition, the Grapevine Reservoir near Dallas, Texas was used to illustrate the use of decision tables to simulate reservoir releases. The releases were conditioned on reservoir volumes and flood season. The release rules as implemented by the decision table realistically simulated flood releases as evidenced by a daily Nash–Sutcliffe Efficiency (NSE of 0.52 and a percent bias of −1.1%. Using decision tables to simulate management in land, river, and reservoir models was shown to have several advantages over current approaches, including: (1 mature technology with considerable literature and applications; (2 ability to accurately represent complex, real world decision-making; (3 code that is efficient, modular, and easy to maintain; and (4 tables that are easy to maintain, support, and modify.

  12. Modifying the Soil and Water Assessment Tool to Simulate Cropland Carbon Flux: Model Development and Initial Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xuesong; Izaurralde, Roberto C.; Arnold, Jeffrey; Williams, Jimmy R.; Srinivasan, Raghavan

    2013-10-01

    Climate change is one of the most compelling modern issues and has important implications for almost every aspect of natural and human systems. The Soil and Water Assessment Tool (SWAT) model has been applied worldwide to support sustainable land and water management in a changing climate. However, the inadequacies of the existing carbon algorithm in SWAT limit its application in assessing impacts of human activities on CO2 emission, one important source of greenhouse gases (GHGs) that traps heat in the earth system and results in global warming. In this research, we incorporate a revised version of the CENTURY carbon model into SWAT to describe dynamics of soil organic matter (SOM)- residue and simulate land-atmosphere carbon exchange.

  13. A Guideline for Successful Calibration and Uncertainty Analysis for Soil and Water Assessment: A Review of Papers from the 2016 International SWAT Conference

    Directory of Open Access Journals (Sweden)

    Karim C. Abbaspour

    2017-12-01

    Full Text Available Application of integrated hydrological models to manage a watershed’s water resources are increasingly finding their way into the decision-making processes. The Soil and Water Assessment Tool (SWAT is a multi-process model integrating hydrology, ecology, agriculture, and water quality. SWAT is a continuation of nearly 40 years of modeling efforts conducted by the United States Department of Agriculture (USDA Agricultural Research Service (ARS. A large number of SWAT-related papers have appeared in ISI journals, building a world-wide consensus around the model’s stability and usefulness. The current issue is a collection of the latest research using SWAT as the modeling tool. Most models must undergo calibration/validation and uncertainty analysis. Unfortunately, these sciences are not formal subjects of teaching in most universities and the students are often left to their own resources to calibrate their model. In this paper, we focus on calibration and uncertainty analysis highlighting some serious issues in the calibration of distributed models. A protocol for calibration is also highlighted to guide the users to obtain better modeling results. Finally, a summary of the papers published in this special issue is provided in the Appendix.

  14. Small hydropower spot prediction using SWAT and a diversion algorithm, case study: Upper Citarum Basin

    Science.gov (United States)

    Kardhana, Hadi; Arya, Doni Khaira; Hadihardaja, Iwan K.; Widyaningtyas, Riawan, Edi; Lubis, Atika

    2017-11-01

    Small-Scale Hydropower (SHP) had been important electric energy power source in Indonesia. Indonesia is vast countries, consists of more than 17.000 islands. It has large fresh water resource about 3 m of rainfall and 2 m of runoff. Much of its topography is mountainous, remote but abundant with potential energy. Millions of people do not have sufficient access to electricity, some live in the remote places. Recently, SHP development was encouraged for energy supply of the places. Development of global hydrology data provides opportunity to predict distribution of hydropower potential. In this paper, we demonstrate run-of-river type SHP spot prediction tool using SWAT and a river diversion algorithm. The use of Soil and Water Assessment Tool (SWAT) with input of CFSR (Climate Forecast System Re-analysis) of 10 years period had been implemented to predict spatially distributed flow cumulative distribution function (CDF). A simple algorithm to maximize potential head of a location by a river diversion expressing head race and penstock had been applied. Firm flow and power of the SHP were estimated from the CDF and the algorithm. The tool applied to Upper Citarum River Basin and three out of four existing hydropower locations had been well predicted. The result implies that this tool is able to support acceleration of SHP development at earlier phase.

  15. Learning to Apply Models of Materials While Explaining Their Properties

    Science.gov (United States)

    Karpin, Tiia; Juuti, Kalle; Lavonen, Jari

    2014-01-01

    Background: Applying structural models is important to chemistry education at the upper secondary level, but it is considered one of the most difficult topics to learn. Purpose: This study analyses to what extent in designed lessons students learned to apply structural models in explaining the properties and behaviours of various materials.…

  16. SWATS: Diurnal Trends in the Soil Temperature Report

    Energy Technology Data Exchange (ETDEWEB)

    Cook, David [Argonne National Lab. (ANL), Argonne, IL (United States); Theisen, Adam [Univ. of Oklahoma, Norman, OK (United States)

    2017-06-30

    During the processing of data for the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Climate Research Facility ARMBE2D Value-Added Product (VAP), the developers noticed that the SWATS soil temperatures did not show a decreased temporal variability with increased depth with the new E30+ Extended Facilities (EFs), unlike the older EFs at ARM’s Southern Great Plains (SGP) site. The instrument mentor analyzed the data and reported that all SWATS locations have shown this behavior but that the magnitude of the problem was greatest at EFs E31-E38. The data were analyzed to verify the initial assessments of: 1. 5 cm SWATS data were valid for all EFs and 15 cm soil temperature measurements were valid at all EFs other than E31-E38, 2. Use only nighttime SWATS soil temperature measurements to calculate daily average soil temperatures, 3. Since it seems likely that the soil temperature measurements below 15cm were affected by the solar heating of the enclosure at all but E31-38, and at all depths below 5cm at E31-38, individual measurements of soil temperature at these depths during daylight hours, and daily averages of the same, can ot be trusted on most (particularly sunny) days.

  17. Residues of cypermethrin and endosulfan in soils of Swat valley

    Directory of Open Access Journals (Sweden)

    M. Nafees

    2009-05-01

    Full Text Available Swat Valley was studied for two widely used pesticides; cypermethrin and endosulfan. A total of 63 soil samples were collected from 27 villages selected for this purpose. The collected soil samples were extracted with n-hexane, pesticides were separated, identified and quantified by a GC-ECD system. Endosulfan was 0.24 - 1.51 mg kg-1 and 0.13 - 12.67 mg kg-1 in rainfed and irrigated areas, respectively. The residual level of cypermethrin was comparatively high with a level of0.14 to 27.62 mg kg-1 and 0.05 to 73.75 mg kg-1 in rainfed and irrigated areas, respectively. For assessing the possible causes of pesticide residues in soil, 360 farmers were interviewed. It was found that both, cypermethrin and endosulfan, apart from agriculture were also widely misused for fishing in the entire stretch of River Swat and its tributaries. River Swat is used for irrigation in Swat Valley and this wide misuse of pesticides can also contribute to pesticide residue in soil.

  18. DEM Resolution Impact on the Estimation of the Physical Characteristics of Watersheds by Using SWAT

    Directory of Open Access Journals (Sweden)

    Waranyu Buakhao

    2016-01-01

    Full Text Available A digital elevation model (DEM is an important spatial input for automatic extraction of topographic parameters for the soil and water assessment tool (SWAT. The objective of this study was to investigate the impact of DEM resolution (from 5 to 90 m on the delineation process of a SWAT model with two types of watershed characteristics (flat area and mountain area and three sizes of watershed area (about 20,000, 200,000, and 1,500,000 hectares. The results showed that the total lengths of the streamline, main channel slope, watershed area, and area slope were significantly different when using the DEM datasets to delineate. Delineation using the SRTM DEM (90 m, ASTER DEM (30 m, and LDD DEM (5 m for all watershed characteristics showed that the watershed sizes and shapes obtained were only slightly different, whereas the area slopes obtained were significantly different. The total lengths of the generated streams increased when the resolution of the DEM used was higher. The stream slopes obtained using the small area sizes were insignificant, whereas the slopes obtained using the large area sizes were significantly different. This suggests that water resource model users should use the ASTER DEM as opposed to a finer resolution DEM for model input to save time for the model calibration and validation.

  19. A nonlinear interface model applied to masonry structures

    Science.gov (United States)

    Lebon, Frédéric; Raffa, Maria Letizia; Rizzoni, Raffaella

    2015-12-01

    In this paper, a new imperfect interface model is presented. The model includes finite strains, micro-cracks and smooth roughness. The model is consistently derived by coupling a homogenization approach for micro-cracked media and arguments of asymptotic analysis. The model is applied to brick/mortar interfaces. Numerical results are presented.

  20. Test results of Run-1 and Run-2 in steam generator safety test facility (SWAT-3)

    International Nuclear Information System (INIS)

    Kurihara, A.; Yatabe, Toshio; Tanabe, Hiromi; Hiroi, Hiroshi

    2003-07-01

    Large leak sodium-water reaction tests were carried out using SWAT-1 rig and SWAT-3 facility in Power Reactor and Nuclear Fuel Development Corporation (PNC) O-arai Engineering Center to obtain the data on the design of the prototype LMFBR Monju steam generator against a large leak accident. This report provides the results of SWAT-3 Runs 1 and 2. In Runs 1 and 2, the heat transfer tube bundle of the evaporator, fabricated by TOSHIBA/IHI, were used, and the pressure relief line was located at the top of evaporator. The water injection rates in the evaporator were 6.7 kg/s and 14.2 (initial)-9.7 kg/s in Runs 1 and 2 respectively, which corresponded to 3.3 tubes and 7.1 (initial)-4.8 tubes failure in actual size system according to iso-velocity modeling. Approximately two hundreds of measurement points were provided to collect data such as pressure, temperature, strain, sodium level, void, thrust load, acceleration, displacement, flow rate, and so on in each run. Initial spike pressures were 1.13 MPa and 2.62 MPa nearest to injection point in Runs 1 and 2 respectively, and the maximum quasi-steady pressures in evaporator were 0.49 MPa and 0.67 MPa in Runs 1 and 2. No secondary tube failure was observed. The rupture disc of evaporator (RD601) burst at 1.1s in Run-1 and at 0.7s in Run-2 after water injected, and the pressure relief system was well-functioned though a few items for improvement were found. (author)

  1. Response of tomato cultivars to different organic fertilizers under agro-climatic conditions of mingora, Swat

    International Nuclear Information System (INIS)

    Yousafzai, S.K.; Khan, S.M.; Khan, J.; Khan, S.A.; Hussain, I.; Naz, I.

    2016-01-01

    An experiment was conducted at Agricultural Research Institute (ARI) Mingora, Swat during 2013 to study the effect of different organic fertilizers of tomato cultivars under the agro-climatic conditions of Mingora, Swat. The experiment was conducted in randomized complete block design with split plot arrangements having four treatments with three replications. Almost all the traits showed significant differences for organic fertilizers and varieties, while their interactions had a varied response. The analyzed data showed that poultry manure gave maximum yield (24.65 t ha/sup -1/), followed by FYM (24.38 t ha/sup -1/) and mushroom compost (24.11 t ha/sup -1/ ) while minimum was recorded in plots where no organic fertilizer was used. The results revealed that cultivar, Rio Grand showed maximum number of plant survival percentage (98.33 percent), days to flowering (40.73), number of flowers plant/sup -1/ (6.23), number of fruit plant (25.67), fruit 3 weight (8.84 kg), number of leaves plant/sup -1/ (83.66), fruit size (64.70 cm/sup 3/) and total yield (25.67 t ha/sup -1/ ) in Farm Yard Manure (FYM). Considering the overall performance, it was found that the tomato cultivar Rio Grand was promising for yield and other characters where FYM was applied. (author)

  2. Estimation of PWR spent fuel composition using SCALE and SWAT code systems

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Hee Sung [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Kenya, Suyama; Hiroshi, Okuno [Japan Atomic Energy Research Institute, Tokyo (Japan)

    2001-05-01

    The isotopic composition calculations were performed for 26 spent fuel samples from Obrigheim PWR reactor and 55 spent fuel samples from 7 PWR reactors using SCALE4.4 SAS2H with 27, 44 and 238 group cross-section libraries and SWAT with 107 group cross-section library. For convenience, the ratio of the measured to calculated value was used as a parameter. The four kinds of the calculation results were compared with the measured data. For many important nuclides for burnup credit criticality safety evaluation, the four methods applied in this study showed good coincidence with measurements in general. More precise observations showed the following results. Less unity ratios were found for Pu-239 and -241 for selected 16 samples out of the 26 samples from Obrigheim reactor. Larger than unity ratios were found for Am-241 for both the 16 and 55 samples. Larger than unity ratios were found for Sm-149 for the 55 samples. In the case of 26 sample SWAT was generally accompanied by larger ratios than those of SAS2H with some exceptions. Based on the measured-to-calculated ratios for 71 samples of a combined set in which 16 selected samples and 55 samples were included, the correction factors that should be multiplied to the calculated isotopic compositions were generated for a conservative estimate of the neutron multiplication factor of a system containing PWR spent fuel, taking burnup credit into account.

  3. Assessing the efficacy of the SWAT auto-irrigation function to simulate Irrigation, evapotranspiration and crop response to irrigation management strategies of the Texas High Plains

    Science.gov (United States)

    The Soil and Water Assessment Tool (SWAT) model is widely used for simulation of hydrologic processes at various temporal and spatial scales. Less common are long-term simulation analyses of water balance components including agricultural management practices such as irrigation management. In the se...

  4. Predicting fecal coliform using the interval-to-interval approach and SWAT in the Miyun watershed, China.

    Science.gov (United States)

    Bai, Jianwen; Shen, Zhenyao; Yan, Tiezhu; Qiu, Jiali; Li, Yangyang

    2017-06-01

    Pathogens in manure can cause waterborne-disease outbreaks, serious illness, and even death in humans. Therefore, information about the transformation and transport of bacteria is crucial for determining their source. In this study, the Soil and Water Assessment Tool (SWAT) was applied to simulate fecal coliform bacteria load in the Miyun Reservoir watershed, China. The data for the fecal coliform were obtained at three sampling sites, Chenying (CY), Gubeikou (GBK), and Xiahui (XH). The calibration processes of the fecal coliform were conducted using the CY and GBK sites, and validation was conducted at the XH site. An interval-to-interval approach was designed and incorporated into the processes of fecal coliform calibration and validation. The 95% confidence interval of the predicted values and the 95% confidence interval of measured values were considered during calibration and validation in the interval-to-interval approach. Compared with the traditional point-to-point comparison, this method can improve simulation accuracy. The results indicated that the simulation of fecal coliform using the interval-to-interval approach was reasonable for the watershed. This method could provide a new research direction for future model calibration and validation studies.

  5. Nonlinear Eddy Viscosity Models applied to Wind Turbine Wakes

    DEFF Research Database (Denmark)

    Laan, van der, Paul Maarten; Sørensen, Niels N.; Réthoré, Pierre-Elouan

    2013-01-01

    The linear k−ε eddy viscosity model and modified versions of two existing nonlinear eddy viscosity models are applied to single wind turbine wake simulations using a Reynolds Averaged Navier-Stokes code. Results are compared with field wake measurements. The nonlinear models give better results...

  6. The Limitations of Applying Rational Decision-Making Models

    African Journals Online (AJOL)

    decision-making models as applied to child spacing and more. specificaDy to the use .... also assumes that the individual operates as a rational decision- making organism in ..... work involves: Motivation; Counselling; Distribution ofIEC mate-.

  7. A BRDF statistical model applying to space target materials modeling

    Science.gov (United States)

    Liu, Chenghao; Li, Zhi; Xu, Can; Tian, Qichen

    2017-10-01

    In order to solve the problem of poor effect in modeling the large density BRDF measured data with five-parameter semi-empirical model, a refined statistical model of BRDF which is suitable for multi-class space target material modeling were proposed. The refined model improved the Torrance-Sparrow model while having the modeling advantages of five-parameter model. Compared with the existing empirical model, the model contains six simple parameters, which can approximate the roughness distribution of the material surface, can approximate the intensity of the Fresnel reflectance phenomenon and the attenuation of the reflected light's brightness with the azimuth angle changes. The model is able to achieve parameter inversion quickly with no extra loss of accuracy. The genetic algorithm was used to invert the parameters of 11 different samples in the space target commonly used materials, and the fitting errors of all materials were below 6%, which were much lower than those of five-parameter model. The effect of the refined model is verified by comparing the fitting results of the three samples at different incident zenith angles in 0° azimuth angle. Finally, the three-dimensional modeling visualizations of these samples in the upper hemisphere space was given, in which the strength of the optical scattering of different materials could be clearly shown. It proved the good describing ability of the refined model at the material characterization as well.

  8. Comparison of two multiaxial fatigue models applied to dental implants

    Directory of Open Access Journals (Sweden)

    JM. Ayllon

    2015-07-01

    Full Text Available This paper presents two multiaxial fatigue life prediction models applied to a commercial dental implant. One model is called Variable Initiation Length Model and takes into account both the crack initiation and propagation phases. The second model combines the Theory of Critical Distance with a critical plane damage model to characterise the initiation and initial propagation of micro/meso cracks in the material. This paper discusses which material properties are necessary for the implementation of these models and how to obtain them in the laboratory from simple test specimens. It also describes the FE models developed for the stress/strain and stress intensity factor characterisation in the implant. The results of applying both life prediction models are compared with experimental results arising from the application of ISO-14801 standard to a commercial dental implant.

  9. Application of SWAT99.2 to sensitivity analysis of water balance components in unique plots in a hilly region

    Directory of Open Access Journals (Sweden)

    Jun-feng Dai

    2017-07-01

    Full Text Available Although many sensitivity analyses using the soil and water assessment tool (SWAT in a complex watershed have been conducted, little attention has been paid to the application potential of the model in unique plots. In addition, sensitivity analysis of percolation and evapotranspiration with SWAT has seldom been undertaken. In this study, SWAT99.2 was calibrated to simulate water balance components for unique plots in Southern China from 2000 to 2001, which included surface runoff, percolation, and evapotranspiration. Twenty-one parameters classified into four categories, including meteorological conditions, topographical characteristics, soil properties, and vegetation attributes, were used for sensitivity analysis through one-at-a-time (OAT sampling to identify the factor that contributed most to the variance in water balance components. The results were shown to be different for different plots, with parameter sensitivity indices and ranks varying for different water balance components. Water balance components in the broad-leaved forest and natural grass plots were most sensitive to meteorological conditions, less sensitive to vegetation attributes and soil properties, and least sensitive to topographical characteristics. Compared to those in the natural grass plot, water balance components in the broad-leaved forest plot demonstrated higher sensitivity to the maximum stomatal conductance (GSI and maximum leaf area index (BLAI.

  10. OpenMP-accelerated SWAT simulation using Intel C and FORTRAN compilers: Development and benchmark

    Science.gov (United States)

    Ki, Seo Jin; Sugimura, Tak; Kim, Albert S.

    2015-02-01

    We developed a practical method to accelerate execution of Soil and Water Assessment Tool (SWAT) using open (free) computational resources. The SWAT source code (rev 622) was recompiled using a non-commercial Intel FORTRAN compiler in Ubuntu 12.04 LTS Linux platform, and newly named iOMP-SWAT in this study. GNU utilities of make, gprof, and diff were used to develop the iOMP-SWAT package, profile memory usage, and check identicalness of parallel and serial simulations. Among 302 SWAT subroutines, the slowest routines were identified using GNU gprof, and later modified using Open Multiple Processing (OpenMP) library in an 8-core shared memory system. In addition, a C wrapping function was used to rapidly set large arrays to zero by cross compiling with the original SWAT FORTRAN package. A universal speedup ratio of 2.3 was achieved using input data sets of a large number of hydrological response units. As we specifically focus on acceleration of a single SWAT run, the use of iOMP-SWAT for parameter calibrations will significantly improve the performance of SWAT optimization.

  11. Sensitivity analysis approaches applied to systems biology models.

    Science.gov (United States)

    Zi, Z

    2011-11-01

    With the rising application of systems biology, sensitivity analysis methods have been widely applied to study the biological systems, including metabolic networks, signalling pathways and genetic circuits. Sensitivity analysis can provide valuable insights about how robust the biological responses are with respect to the changes of biological parameters and which model inputs are the key factors that affect the model outputs. In addition, sensitivity analysis is valuable for guiding experimental analysis, model reduction and parameter estimation. Local and global sensitivity analysis approaches are the two types of sensitivity analysis that are commonly applied in systems biology. Local sensitivity analysis is a classic method that studies the impact of small perturbations on the model outputs. On the other hand, global sensitivity analysis approaches have been applied to understand how the model outputs are affected by large variations of the model input parameters. In this review, the author introduces the basic concepts of sensitivity analysis approaches applied to systems biology models. Moreover, the author discusses the advantages and disadvantages of different sensitivity analysis methods, how to choose a proper sensitivity analysis approach, the available sensitivity analysis tools for systems biology models and the caveats in the interpretation of sensitivity analysis results.

  12. An extended gravity model with substitution applied to international trade

    NARCIS (Netherlands)

    Bikker, J.A.|info:eu-repo/dai/nl/06912261X

    The traditional gravity model has been applied many times to international trade flows, especially in order to analyze trade creation and trade diversion. However, there are two fundamental objections to the model: it cannot describe substitutions between flows and it lacks a cogent theoretical

  13. Exponential models applied to automated processing of radioimmunoassay standard curves

    International Nuclear Information System (INIS)

    Morin, J.F.; Savina, A.; Caroff, J.; Miossec, J.; Legendre, J.M.; Jacolot, G.; Morin, P.P.

    1979-01-01

    An improved computer processing is described for fitting of radio-immunological standard curves by means of an exponential model on a desk-top calculator. This method has been applied to a variety of radioassays and the results are in accordance with those obtained by more sophisticated models [fr

  14. INCIDENCE OF NAMATODE PARASITES IN COMMERCIAL LAYERS IN SWAT

    OpenAIRE

    R.S. Sayyed, M.S. Phulan1, W.M. Bhatti1, M. Pardehi and Shamsher Ali

    2000-01-01

    Research was conducted on 400 guts of commercial layers collected from various shops at District Swat during April to September 1998. Out of 400 guts, 36 per cent were positive for nematodes, Mixed infestation of nematodes and cestodes was found in 4.75 per cent layers. Incidence rate of Ascaridia galli, Heterakis gallinarum and Subulura brumpli was 25.75, 8.25 and 2 per cent, respectively.

  15. INCIDENCE OF NAMATODE PARASITES IN COMMERCIAL LAYERS IN SWAT

    Directory of Open Access Journals (Sweden)

    R.S. Sayyed, M.S. Phulan1, W.M. Bhatti1, M. Pardehi and Shamsher Ali

    2000-04-01

    Full Text Available Research was conducted on 400 guts of commercial layers collected from various shops at District Swat during April to September 1998. Out of 400 guts, 36 per cent were positive for nematodes, Mixed infestation of nematodes and cestodes was found in 4.75 per cent layers. Incidence rate of Ascaridia galli, Heterakis gallinarum and Subulura brumpli was 25.75, 8.25 and 2 per cent, respectively.

  16. Characterization of emerald from Gujar Kili, Swat, Pakistan

    International Nuclear Information System (INIS)

    Qureshi, A.A.; Akram, M.; Khattak, N.U.; Khan, H.A.

    1997-01-01

    The green gem variety of beryl family having Cr as colouring agent is known as emerald. Thirteen emerald occurrences are known from northern Pakistan. These occurrences are in Mohamand Agency, Bajuar Agency, Swat District, Indus Kohistan and Gilgit which are located exclusively in the metamorphosed ophiolitic melange of the Indus Suture Zone. The ophiolitic rocks of this suture are the source of Cr which colours the beryl to make it emerald. Studies have been carried out for the characterisation of emerald from one locality, Gujar Kili in Swat district, using petrographic, XRD, XRF and fission track techniques. The Gujar Kili emerald is of green to deep green colour good quality gemstone and contains inclusions in some cases. In general, the Gujar Kili emerald has high Mg, Fe, Cr, V and Al values as compared to average composition of natural emeralds of Swat District. Two mineralogical phases, namely beryl and chrysoberyl have been identified in the four Gujar Kili samples analysed by us. The XRD data for the beryl and chrysoberyl is also presented. The Cr which colours the beryl to make it emerald, does not substitute any element in the beryl structure, rather it is present as an impurity in the crystal matrix. A new etchant to reveal fission tracks in a very short time is also being reported in this paper. (author)

  17. Experiments on injection performance of SMART ECC facility using SWAT

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Young Il; Cho, Seok; Ko, Yung Joo; Min, Kyoung Ho; Shin, Yong Cheol; Kwon, Tae Soon; Yi, Sung Jae; Lee, Won Jae [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2012-05-15

    SMART (System-integrated Modular Advanced ReacTor), an advanced integrated PWR is now in the under developing stages by KAERI. Such integral PWR excludes large-size piping of the primary system of conventional PWR and incorporates the SGs into RPV, which means no LBLOCA could occur in SMART. Therefore, the SBLOCA is considered as a major DBA (Design Basis Accident) in SMART and it is mainly analyzed by using TASS/SMR computer code. The TASS/SMR code should be validated using experimental data from both Integral Effect Test and Separate Effect Test facilities. To investigate injection performance of the ECC system, on SET facility, named as SWAT (SMART ECC Water Asymmetric Two-phase choking test facility), has been constructed at KAERI. The SWAT simulates the geometric configurations of the SG-side upper downcomer annulus and ECCSs of those of SMART. It is designed based on the modified linear scaling method with a scaling ratio of 1/5, to preserve the geometrical similarity and minimize gravitational distortion. The purpose of the SWAT tests is to investigate the safety injection performance, such as the ECC bypass in the downcomer and the penetration rate in the core during the SBLOCA, and hence to produce experimental data to validate and the prediction capability of safety analysis codes, TASS/SMR

  18. Modeling in applied sciences a kinetic theory approach

    CERN Document Server

    Pulvirenti, Mario

    2000-01-01

    Modeling complex biological, chemical, and physical systems, in the context of spatially heterogeneous mediums, is a challenging task for scientists and engineers using traditional methods of analysis Modeling in Applied Sciences is a comprehensive survey of modeling large systems using kinetic equations, and in particular the Boltzmann equation and its generalizations An interdisciplinary group of leading authorities carefully develop the foundations of kinetic models and discuss the connections and interactions between model theories, qualitative and computational analysis and real-world applications This book provides a thoroughly accessible and lucid overview of the different aspects, models, computations, and methodology for the kinetic-theory modeling process Topics and Features * Integrated modeling perspective utilized in all chapters * Fluid dynamics of reacting gases * Self-contained introduction to kinetic models * Becker–Doring equations * Nonlinear kinetic models with chemical reactions * Kinet...

  19. LEARNING SEMANTICS-ENHANCED LANGUAGE MODELS APPLIED TO UNSUEPRVISED WSD

    Energy Technology Data Exchange (ETDEWEB)

    VERSPOOR, KARIN [Los Alamos National Laboratory; LIN, SHOU-DE [Los Alamos National Laboratory

    2007-01-29

    An N-gram language model aims at capturing statistical syntactic word order information from corpora. Although the concept of language models has been applied extensively to handle a variety of NLP problems with reasonable success, the standard model does not incorporate semantic information, and consequently limits its applicability to semantic problems such as word sense disambiguation. We propose a framework that integrates semantic information into the language model schema, allowing a system to exploit both syntactic and semantic information to address NLP problems. Furthermore, acknowledging the limited availability of semantically annotated data, we discuss how the proposed model can be learned without annotated training examples. Finally, we report on a case study showing how the semantics-enhanced language model can be applied to unsupervised word sense disambiguation with promising results.

  20. Analytic model of Applied-B ion diode impedance behavior

    International Nuclear Information System (INIS)

    Miller, P.A.; Mendel, C.W. Jr.

    1987-01-01

    An empirical analysis of impedance data from Applied-B ion diodes used in seven inertial confinement fusion research experiments was published recently. The diodes all operated with impedance values well below the Child's-law value. The analysis uncovered an unusual unifying relationship among data from the different experiments. The analysis suggested that closure of the anode-cathode gap by electrode plasma was not a dominant factor in the experiments, but was not able to elaborate the underlying physics. Here we present a new analytic model of Applied-B ion diodes coupled to accelerators. A critical feature of the diode model is based on magnetic insulation theory. The model successfully describes impedance behavior of these diodes and supports stimulating new viewpoints of the physics of Applied-B ion diode operation

  1. Methods for model selection in applied science and engineering.

    Energy Technology Data Exchange (ETDEWEB)

    Field, Richard V., Jr.

    2004-10-01

    Mathematical models are developed and used to study the properties of complex systems and/or modify these systems to satisfy some performance requirements in just about every area of applied science and engineering. A particular reason for developing a model, e.g., performance assessment or design, is referred to as the model use. Our objective is the development of a methodology for selecting a model that is sufficiently accurate for an intended use. Information on the system being modeled is, in general, incomplete, so that there may be two or more models consistent with the available information. The collection of these models is called the class of candidate models. Methods are developed for selecting the optimal member from a class of candidate models for the system. The optimal model depends on the available information, the selected class of candidate models, and the model use. Classical methods for model selection, including the method of maximum likelihood and Bayesian methods, as well as a method employing a decision-theoretic approach, are formulated to select the optimal model for numerous applications. There is no requirement that the candidate models be random. Classical methods for model selection ignore model use and require data to be available. Examples are used to show that these methods can be unreliable when data is limited. The decision-theoretic approach to model selection does not have these limitations, and model use is included through an appropriate utility function. This is especially important when modeling high risk systems, where the consequences of using an inappropriate model for the system can be disastrous. The decision-theoretic method for model selection is developed and applied for a series of complex and diverse applications. These include the selection of the: (1) optimal order of the polynomial chaos approximation for non-Gaussian random variables and stationary stochastic processes, (2) optimal pressure load model to be

  2. Hydrological Modeling of Highly Glacierized Basins (Andes, Alps, and Central Asia

    Directory of Open Access Journals (Sweden)

    Nina Omani

    2017-02-01

    Full Text Available The Soil and Water Assessment Tool (SWAT was used to simulate five glacierized river basins that are global in coverage and vary in climate. The river basins included the Narayani (Nepal, Vakhsh (Central Asia, Rhone (Switzerland, Mendoza (Central Andes, Argentina, and Central Dry Andes (Chile, with a total area of 85,000 km2. A modified SWAT snow algorithm was applied in order to consider spatial variation of associated snowmelt/accumulation by elevation band across each subbasin. In previous studies, melt rates varied as a function of elevation because of an air temperature gradient while the snow parameters were constant throughout the entire basin. A major improvement of the new snow algorithm is the separation of the glaciers from seasonal snow based on their characteristics. Two SWAT snow algorithms were evaluated in simulation of monthly runoff from the glaciered watersheds: (1 the snow parameters are lumped (constant throughout the entire basin and (2 the snow parameters are spatially variable based on elevation bands of a subbasin (modified snow algorithm. Applying the distributed SWAT snow algorithm improved the model performance in simulation of monthly runoff with snow-glacial regime, so that mean RSR decreased to 0.49 from 0.55 and NSE increased to 0.75 from 0.69. Improvement of model performance was negligible in simulations of monthly runoff from the basins with a monsoon runoff regime.

  3. Use of a watershed model to characterize the fate and transport of fluometuron, a soil-applied cotton herbicide, in surface water

    Science.gov (United States)

    Coupe, R.H.

    2007-01-01

    The Soil and Water Assessment Tool (SWAT) was used to characterize the fate and transport of fluometuron (a herbicide used on cotton) in the Bogue Phalia Basin in northwestern Mississippi, USA. SWAT is a basin-scale watershed model, able to simulate hydrological, chemical, and sediment transport processes. After adjustments to a few parameters (specifically the SURLAG variable, the runoff curve number, Manning's N for overland flow, soil available water capacity, and the base-flow alpha factor) the SWAT model fit the observed streamflow well (the Coefficient of Efficiency and R2 were greater than 60). The results from comparing observed fluometuron concentrations with simulated concentrations were reasonable. The simulated concentrations (which were daily averages) followed the pattern of observed concentrations (instantaneous values) closely, but could be off in magnitude at times. Further calibration might have improved the fit, but given the uncertainties in the input data, it was not clear that any improvement would be due to a better understanding of the input variables. ?? 2007 Taylor & Francis.

  4. Using SWAT-MODFLOW to simulate groundwater flow and groundwater-surface water interactions in an intensively irrigated stream-aquifer system

    Science.gov (United States)

    Wei, X.; Bailey, R. T.

    2017-12-01

    Agricultural irrigated watersheds in semi-arid regions face challenges such as waterlogging, high soil salinity, reduced crop yield, and leaching of chemical species due to extreme shallow water tables resulting from long-term intensive irrigation. Hydrologic models can be used to evaluate the impact of land management practices on water yields and groundwater-surface water interactions in such regions. In this study, the newly developed SWAT-MODFLOW, a coupled surface/subsurface hydrologic model, is applied to a 950 km2 watershed in the Lower Arkansas River Valley (southeastern Colorado). The model accounts for the influence of canal diversions, irrigation applications, groundwater pumping, and earth canal seepage losses. The model provides a detailed description of surface and subsurface flow processes, thereby enabling detailed description of watershed processes such as runoff, infiltration, in-streamflow, three-dimensional groundwater flow in a heterogeneous aquifer system with sources and sinks (e.g. pumping, seepage to subsurface drains), and spatially-variable surface and groundwater exchange. The model was calibrated and tested against stream discharge from 5 stream gauges in the Arkansas River and its tributaries, groundwater levels from 70 observation wells, and evapotranspiration (ET) data estimated from satellite (ReSET) data during the 1999 to 2007 period. Since the water-use patterns within the study area are typical of many other irrigated river valleys in the United States and elsewhere, this modeling approach is transferable to other regions.

  5. Modeling Organizational Design - Applying A Formalism Model From Theoretical Physics

    Directory of Open Access Journals (Sweden)

    Robert Fabac

    2008-06-01

    Full Text Available Modern organizations are exposed to diverse external environment influences. Currently accepted concepts of organizational design take into account structure, its interaction with strategy, processes, people, etc. Organization design and planning aims to align this key organizational design variables. At the higher conceptual level, however, completely satisfactory formulation for this alignment doesn’t exist. We develop an approach originating from the application of concepts of theoretical physics to social systems. Under this approach, the allocation of organizational resources is analyzed in terms of social entropy, social free energy and social temperature. This allows us to formalize the dynamic relationship between organizational design variables. In this paper we relate this model to Galbraith's Star Model and we also suggest improvements in the procedure of the complex analytical method in organizational design.

  6. Applied data analysis and modeling for energy engineers and scientists

    CERN Document Server

    Reddy, T Agami

    2011-01-01

    ""Applied Data Analysis and Modeling for Energy Engineers and Scientists"" discusses mathematical models, data analysis, and decision analysis in modeling. The approach taken in this volume focuses on the modeling and analysis of thermal systems in an engineering environment, while also covering a number of other critical areas. Other material covered includes the tools that researchers and engineering professionals will need in order to explore different analysis methods, use critical assessment skills and reach sound engineering conclusions. The book also covers process and system design and

  7. Linear mixing model applied to coarse resolution satellite data

    Science.gov (United States)

    Holben, Brent N.; Shimabukuro, Yosio E.

    1992-01-01

    A linear mixing model typically applied to high resolution data such as Airborne Visible/Infrared Imaging Spectrometer, Thematic Mapper, and Multispectral Scanner System is applied to the NOAA Advanced Very High Resolution Radiometer coarse resolution satellite data. The reflective portion extracted from the middle IR channel 3 (3.55 - 3.93 microns) is used with channels 1 (0.58 - 0.68 microns) and 2 (0.725 - 1.1 microns) to run the Constrained Least Squares model to generate fraction images for an area in the west central region of Brazil. The derived fraction images are compared with an unsupervised classification and the fraction images derived from Landsat TM data acquired in the same day. In addition, the relationship betweeen these fraction images and the well known NDVI images are presented. The results show the great potential of the unmixing techniques for applying to coarse resolution data for global studies.

  8. The sdg interacting-boson model applied to 168Er

    Science.gov (United States)

    Yoshinaga, N.; Akiyama, Y.; Arima, A.

    1986-03-01

    The sdg interacting-boson model is applied to 168Er. Energy levels and E2 transitions are calculated. This model is shown to solve the problem of anharmonicity regarding the excitation energy of the first Kπ=4+ band relative to that of the first Kπ=2+ one. The level scheme including the Kπ=3+ band is well reproduced and the calculated B(E2)'s are consistent with the experimental data.

  9. Remarks on orthotropic elastic models applied to wood

    Directory of Open Access Journals (Sweden)

    Nilson Tadeu Mascia

    2006-09-01

    Full Text Available Wood is generally considered an anisotropic material. In terms of engineering elastic models, wood is usually treated as an orthotropic material. This paper presents an analysis of two principal anisotropic elastic models that are usually applied to wood. The first one, the linear orthotropic model, where the material axes L (Longitudinal, R( radial and T(tangential are coincident with the Cartesian axes (x, y, z, is more accepted as wood elastic model. The other one, the cylindrical orthotropic model is more adequate of the growth caracteristics of wood but more mathematically complex to be adopted in practical terms. Specifically due to its importance in wood elastic parameters, this paper deals with the fiber orientation influence in these models through adequate transformation of coordinates. As a final result, some examples of the linear model, which show the variation of elastic moduli, i.e., Young´s modulus and shear modulus, with fiber orientation are presented.

  10. An applied general equilibrium model for Dutch agribusiness policy analysis

    NARCIS (Netherlands)

    Peerlings, J.

    1993-01-01

    The purpose of this thesis was to develop a basic static applied general equilibrium (AGE) model to analyse the effects of agricultural policy changes on Dutch agribusiness. In particular the effects on inter-industry transactions, factor demand, income, and trade are of

  11. The limitations of applying rational decision-making models to ...

    African Journals Online (AJOL)

    The aim of this paper is to show the limitations of rational decision-making models as applied to child spacing and more specifically to the use of modern methods of contraception. In the light of factors known to influence low uptake of child spacing services in other African countries, suggestions are made to explain the ...

  12. Applying the Flipped Classroom Model to English Language Arts Education

    Science.gov (United States)

    Young, Carl A., Ed.; Moran, Clarice M., Ed.

    2017-01-01

    The flipped classroom method, particularly when used with digital video, has recently attracted many supporters within the education field. Now more than ever, language arts educators can benefit tremendously from incorporating flipped classroom techniques into their curriculum. "Applying the Flipped Classroom Model to English Language Arts…

  13. The Pennsylvania Phosphorus Index and TopoSWAT: A comparison of transport components and approaches

    Science.gov (United States)

    The regional Chesapeake Bay Conservation Innovation Grant Initiative includes comparison of TopoSWAT results and Phosphorus Index (P Index) evaluations of eight study watersheds throughout the Chesapeake Bay watershed. While similarities exist between the P Index and TopoSWAT, further comparison of ...

  14. Molecular modeling: An open invitation for applied mathematics

    Science.gov (United States)

    Mezey, Paul G.

    2013-10-01

    Molecular modeling methods provide a very wide range of challenges for innovative mathematical and computational techniques, where often high dimensionality, large sets of data, and complicated interrelations imply a multitude of iterative approximations. The physical and chemical basis of these methodologies involves quantum mechanics with several non-intuitive aspects, where classical interpretation and classical analogies are often misleading or outright wrong. Hence, instead of the everyday, common sense approaches which work so well in engineering, in molecular modeling one often needs to rely on rather abstract mathematical constraints and conditions, again emphasizing the high level of reliance on applied mathematics. Yet, the interdisciplinary aspects of the field of molecular modeling also generates some inertia and perhaps too conservative reliance on tried and tested methodologies, that is at least partially caused by the less than up-to-date involvement in the newest developments in applied mathematics. It is expected that as more applied mathematicians take up the challenge of employing the latest advances of their field in molecular modeling, important breakthroughs may follow. In this presentation some of the current challenges of molecular modeling are discussed.

  15. Applying a realistic evaluation model to occupational safety interventions

    DEFF Research Database (Denmark)

    Pedersen, Louise Møller

    2018-01-01

    Background: Recent literature characterizes occupational safety interventions as complex social activities, applied in complex and dynamic social systems. Hence, the actual outcomes of an intervention will vary, depending on the intervention, the implementation process, context, personal characte......Background: Recent literature characterizes occupational safety interventions as complex social activities, applied in complex and dynamic social systems. Hence, the actual outcomes of an intervention will vary, depending on the intervention, the implementation process, context, personal...... and qualitative methods. This revised model has, however, not been applied in a real life context. Method: The model is applied in a controlled, four-component, integrated behaviour-based and safety culture-based safety intervention study (2008-2010) in a medium-sized wood manufacturing company. The interventions...... involve the company’s safety committee, safety manager, safety groups and 130 workers. Results: The model provides a framework for more valid evidence of what works within injury prevention. Affective commitment and role behaviour among key actors are identified as crucial for the implementation...

  16. Applying Model Based Systems Engineering to NASA's Space Communications Networks

    Science.gov (United States)

    Bhasin, Kul; Barnes, Patrick; Reinert, Jessica; Golden, Bert

    2013-01-01

    System engineering practices for complex systems and networks now require that requirement, architecture, and concept of operations product development teams, simultaneously harmonize their activities to provide timely, useful and cost-effective products. When dealing with complex systems of systems, traditional systems engineering methodology quickly falls short of achieving project objectives. This approach is encumbered by the use of a number of disparate hardware and software tools, spreadsheets and documents to grasp the concept of the network design and operation. In case of NASA's space communication networks, since the networks are geographically distributed, and so are its subject matter experts, the team is challenged to create a common language and tools to produce its products. Using Model Based Systems Engineering methods and tools allows for a unified representation of the system in a model that enables a highly related level of detail. To date, Program System Engineering (PSE) team has been able to model each network from their top-level operational activities and system functions down to the atomic level through relational modeling decomposition. These models allow for a better understanding of the relationships between NASA's stakeholders, internal organizations, and impacts to all related entities due to integration and sustainment of existing systems. Understanding the existing systems is essential to accurate and detailed study of integration options being considered. In this paper, we identify the challenges the PSE team faced in its quest to unify complex legacy space communications networks and their operational processes. We describe the initial approaches undertaken and the evolution toward model based system engineering applied to produce Space Communication and Navigation (SCaN) PSE products. We will demonstrate the practice of Model Based System Engineering applied to integrating space communication networks and the summary of its

  17. Agrochemical fate models applied in agricultural areas from Colombia

    Science.gov (United States)

    Garcia-Santos, Glenda; Yang, Jing; Andreoli, Romano; Binder, Claudia

    2010-05-01

    The misuse application of pesticides in mainly agricultural catchments can lead to severe problems for humans and environment. Especially in developing countries where there is often found overuse of agrochemicals and incipient or lack of water quality monitoring at local and regional levels, models are needed for decision making and hot spots identification. However, the complexity of the water cycle contrasts strongly with the scarce data availability, limiting the number of analysis, techniques, and models available to researchers. Therefore there is a strong need for model simplification able to appropriate model complexity and still represent the processes. We have developed a new model so-called Westpa-Pest to improve water quality management of an agricultural catchment located in the highlands of Colombia. Westpa-Pest is based on the fully distributed hydrologic model Wetspa and a fate pesticide module. We have applied a multi-criteria analysis for model selection under the conditions and data availability found in the region and compared with the new developed Westpa-Pest model. Furthermore, both models were empirically calibrated and validated. The following questions were addressed i) what are the strengths and weaknesses of the models?, ii) which are the most sensitive parameters of each model?, iii) what happens with uncertainties in soil parameters?, and iv) how sensitive are the transfer coefficients?

  18. A general diagnostic model applied to language testing data.

    Science.gov (United States)

    von Davier, Matthias

    2008-11-01

    Probabilistic models with one or more latent variables are designed to report on a corresponding number of skills or cognitive attributes. Multidimensional skill profiles offer additional information beyond what a single test score can provide, if the reported skills can be identified and distinguished reliably. Many recent approaches to skill profile models are limited to dichotomous data and have made use of computationally intensive estimation methods such as Markov chain Monte Carlo, since standard maximum likelihood (ML) estimation techniques were deemed infeasible. This paper presents a general diagnostic model (GDM) that can be estimated with standard ML techniques and applies to polytomous response variables as well as to skills with two or more proficiency levels. The paper uses one member of a larger class of diagnostic models, a compensatory diagnostic model for dichotomous and partial credit data. Many well-known models, such as univariate and multivariate versions of the Rasch model and the two-parameter logistic item response theory model, the generalized partial credit model, as well as a variety of skill profile models, are special cases of this GDM. In addition to an introduction to this model, the paper presents a parameter recovery study using simulated data and an application to real data from the field test for TOEFL Internet-based testing.

  19. Applied systems ecology: models, data, and statistical methods

    Energy Technology Data Exchange (ETDEWEB)

    Eberhardt, L L

    1976-01-01

    In this report, systems ecology is largely equated to mathematical or computer simulation modelling. The need for models in ecology stems from the necessity to have an integrative device for the diversity of ecological data, much of which is observational, rather than experimental, as well as from the present lack of a theoretical structure for ecology. Different objectives in applied studies require specialized methods. The best predictive devices may be regression equations, often non-linear in form, extracted from much more detailed models. A variety of statistical aspects of modelling, including sampling, are discussed. Several aspects of population dynamics and food-chain kinetics are described, and it is suggested that the two presently separated approaches should be combined into a single theoretical framework. It is concluded that future efforts in systems ecology should emphasize actual data and statistical methods, as well as modelling.

  20. Agroecology and biodiversity of the catchment area of Swat River

    International Nuclear Information System (INIS)

    Ahmad, H.; Ahmed, R.

    2003-01-01

    Agroecological studies of the of the Swat River catchment area showed that the terrestrial ecosystem of the area is divided into subtropical, humid temperate, cool temperate, cold temperate, subalpine, alpine and cold desert zones. Indicator species along with their altitudinal limits are specified for each zone. Unplanned population growth, agriculture extension, habitat losses, deforestation, environmental pollution and unwise use of natural resources are threats to the natural biodiversity of these zones. Its severity is very evident in the subtropical and humid temperate zones. The losses encountered to the biodiversity of the area under the influence of various anthropogenic stresses are highlighted. (author)

  1. Applying model predictive control to power system frequency control

    OpenAIRE

    Ersdal, AM; Imsland, L; Cecilio, IM; Fabozzi, D; Thornhill, NF

    2013-01-01

    16.07.14 KB Ok to add accepted version to Spiral Model predictive control (MPC) is investigated as a control method which may offer advantages in frequency control of power systems than the control methods applied today, especially in presence of increased renewable energy penetration. The MPC includes constraints on both generation amount and generation rate of change, and it is tested on a one-area system. The proposed MPC is tested against a conventional proportional-integral (PI) cont...

  2. Applied model for the growth of the daytime mixed layer

    DEFF Research Database (Denmark)

    Batchvarova, E.; Gryning, Sven-Erik

    1991-01-01

    numerically. When the mixed layer is shallow or the atmosphere nearly neutrally stratified, the growth is controlled mainly by mechanical turbulence. When the layer is deep, its growth is controlled mainly by convective turbulence. The model is applied on a data set of the evolution of the height of the mixed...... layer in the morning hours, when both mechanical and convective turbulence contribute to the growth process. Realistic mixed-layer developments are obtained....

  3. Fractional calculus model of electrical impedance applied to human skin.

    Science.gov (United States)

    Vosika, Zoran B; Lazovic, Goran M; Misevic, Gradimir N; Simic-Krstic, Jovana B

    2013-01-01

    Fractional calculus is a mathematical approach dealing with derivatives and integrals of arbitrary and complex orders. Therefore, it adds a new dimension to understand and describe basic nature and behavior of complex systems in an improved way. Here we use the fractional calculus for modeling electrical properties of biological systems. We derived a new class of generalized models for electrical impedance and applied them to human skin by experimental data fitting. The primary model introduces new generalizations of: 1) Weyl fractional derivative operator, 2) Cole equation, and 3) Constant Phase Element (CPE). These generalizations were described by the novel equation which presented parameter [Formula: see text] related to remnant memory and corrected four essential parameters [Formula: see text] We further generalized single generalized element by introducing specific partial sum of Maclaurin series determined by parameters [Formula: see text] We defined individual primary model elements and their serial combination models by the appropriate equations and electrical schemes. Cole equation is a special case of our generalized class of models for[Formula: see text] Previous bioimpedance data analyses of living systems using basic Cole and serial Cole models show significant imprecisions. Our new class of models considerably improves the quality of fitting, evaluated by mean square errors, for bioimpedance data obtained from human skin. Our models with new parameters presented in specific partial sum of Maclaurin series also extend representation, understanding and description of complex systems electrical properties in terms of remnant memory effects.

  4. Fractional calculus model of electrical impedance applied to human skin.

    Directory of Open Access Journals (Sweden)

    Zoran B Vosika

    Full Text Available Fractional calculus is a mathematical approach dealing with derivatives and integrals of arbitrary and complex orders. Therefore, it adds a new dimension to understand and describe basic nature and behavior of complex systems in an improved way. Here we use the fractional calculus for modeling electrical properties of biological systems. We derived a new class of generalized models for electrical impedance and applied them to human skin by experimental data fitting. The primary model introduces new generalizations of: 1 Weyl fractional derivative operator, 2 Cole equation, and 3 Constant Phase Element (CPE. These generalizations were described by the novel equation which presented parameter [Formula: see text] related to remnant memory and corrected four essential parameters [Formula: see text] We further generalized single generalized element by introducing specific partial sum of Maclaurin series determined by parameters [Formula: see text] We defined individual primary model elements and their serial combination models by the appropriate equations and electrical schemes. Cole equation is a special case of our generalized class of models for[Formula: see text] Previous bioimpedance data analyses of living systems using basic Cole and serial Cole models show significant imprecisions. Our new class of models considerably improves the quality of fitting, evaluated by mean square errors, for bioimpedance data obtained from human skin. Our models with new parameters presented in specific partial sum of Maclaurin series also extend representation, understanding and description of complex systems electrical properties in terms of remnant memory effects.

  5. Online traffic flow model applying dynamic flow-density relation

    International Nuclear Information System (INIS)

    Kim, Y.

    2002-01-01

    This dissertation describes a new approach of the online traffic flow modelling based on the hydrodynamic traffic flow model and an online process to adapt the flow-density relation dynamically. The new modelling approach was tested based on the real traffic situations in various homogeneous motorway sections and a motorway section with ramps and gave encouraging simulation results. This work is composed of two parts: first the analysis of traffic flow characteristics and second the development of a new online traffic flow model applying these characteristics. For homogeneous motorway sections traffic flow is classified into six different traffic states with different characteristics. Delimitation criteria were developed to separate these states. The hysteresis phenomena were analysed during the transitions between these traffic states. The traffic states and the transitions are represented on a states diagram with the flow axis and the density axis. For motorway sections with ramps the complicated traffic flow is simplified and classified into three traffic states depending on the propagation of congestion. The traffic states are represented on a phase diagram with the upstream demand axis and the interaction strength axis which was defined in this research. The states diagram and the phase diagram provide a basis for the development of the dynamic flow-density relation. The first-order hydrodynamic traffic flow model was programmed according to the cell-transmission scheme extended by the modification of flow dependent sending/receiving functions, the classification of cells and the determination strategy for the flow-density relation in the cells. The unreasonable results of macroscopic traffic flow models, which may occur in the first and last cells in certain conditions are alleviated by applying buffer cells between the traffic data and the model. The sending/receiving functions of the cells are determined dynamically based on the classification of the

  6. Eliciting expert opinion for economic models: an applied example.

    Science.gov (United States)

    Leal, José; Wordsworth, Sarah; Legood, Rosa; Blair, Edward

    2007-01-01

    Expert opinion is considered as a legitimate source of information for decision-analytic modeling where required data are unavailable. Our objective was to develop a practical computer-based tool for eliciting expert opinion about the shape of the uncertainty distribution around individual model parameters. We first developed a prepilot survey with departmental colleagues to test a number of alternative approaches to eliciting opinions on the shape of the uncertainty distribution around individual parameters. This information was used to develop a survey instrument for an applied clinical example. This involved eliciting opinions from experts to inform a number of parameters involving Bernoulli processes in an economic model evaluating DNA testing for families with a genetic disease, hypertrophic cardiomyopathy. The experts were cardiologists, clinical geneticists, and laboratory scientists working with cardiomyopathy patient populations and DNA testing. Our initial prepilot work suggested that the more complex elicitation techniques advocated in the literature were difficult to use in practice. In contrast, our approach achieved a reasonable response rate (50%), provided logical answers, and was generally rated as easy to use by respondents. The computer software user interface permitted graphical feedback throughout the elicitation process. The distributions obtained were incorporated into the model, enabling the use of probabilistic sensitivity analysis. There is clearly a gap in the literature between theoretical elicitation techniques and tools that can be used in applied decision-analytic models. The results of this methodological study are potentially valuable for other decision analysts deriving expert opinion.

  7. Surface-bounded growth modeling applied to human mandibles

    DEFF Research Database (Denmark)

    Andresen, Per Rønsholt

    1999-01-01

    This thesis presents mathematical and computational techniques for three dimensional growth modeling applied to human mandibles. The longitudinal shape changes make the mandible a complex bone. The teeth erupt and the condylar processes change direction, from pointing predominantly backward...... of the common features. 3.model the process that moves the matched points (growth modeling). A local shape feature called crest line has shown itself to be structurally stable on mandibles. Registration of crest lines (from different mandibles) results in a sparse deformation field, which must be interpolated...... old mandible based on the 3 month old scan. When using successively more recent scans as basis for the model the error drops to 2.0 mm for the 11 years old scan. Thus, it seems reasonable to assume that the mandibular growth is linear....

  8. Fuzzy model predictive control algorithm applied in nuclear power plant

    International Nuclear Information System (INIS)

    Zuheir, Ahmad

    2006-01-01

    The aim of this paper is to design a predictive controller based on a fuzzy model. The Takagi-Sugeno fuzzy model with an Adaptive B-splines neuro-fuzzy implementation is used and incorporated as a predictor in a predictive controller. An optimization approach with a simplified gradient technique is used to calculate predictions of the future control actions. In this approach, adaptation of the fuzzy model using dynamic process information is carried out to build the predictive controller. The easy description of the fuzzy model and the easy computation of the gradient sector during the optimization procedure are the main advantages of the computation algorithm. The algorithm is applied to the control of a U-tube steam generation unit (UTSG) used for electricity generation. (author)

  9. A comparison of single- and multi-site calibration and validation: a case study of SWAT in the Miyun Reservoir watershed, China

    Science.gov (United States)

    Bai, Jianwen; Shen, Zhenyao; Yan, Tiezhu

    2017-09-01

    An essential task in evaluating global water resource and pollution problems is to obtain the optimum set of parameters in hydrological models through calibration and validation. For a large-scale watershed, single-site calibration and validation may ignore spatial heterogeneity and may not meet the needs of the entire watershed. The goal of this study is to apply a multi-site calibration and validation of the Soil andWater Assessment Tool (SWAT), using the observed flow data at three monitoring sites within the Baihe watershed of the Miyun Reservoir watershed, China. Our results indicate that the multi-site calibration parameter values are more reasonable than those obtained from single-site calibrations. These results are mainly due to significant differences in the topographic factors over the large-scale area, human activities and climate variability. The multi-site method involves the division of the large watershed into smaller watersheds, and applying the calibrated parameters of the multi-site calibration to the entire watershed. It was anticipated that this case study could provide experience of multi-site calibration in a large-scale basin, and provide a good foundation for the simulation of other pollutants in followup work in the Miyun Reservoir watershed and other similar large areas.

  10. Sodium-water reaction test facility (SWAT-3)

    International Nuclear Information System (INIS)

    Shimazu, Hisashi; Ukechi, Kazutoshi; Sasakura, Kazutake; Kusunoki, Junichi

    1976-01-01

    In the development of the liquid metal cooled fast breeder reactor (LMFBR), the steam generator (SG) is considered one of the most important components. The Power Reactor and Nuclear Fuel Development Corporation (PNC) is now promoting the research and development of the SG system used with the prototype fast breeder reactor ''Monju''. In this research, the phenomena of the sodium-water reaction in the SG are the key which must be investigated for the solution of problems. The test facility (SWAT-3) simulating Monju's SG on the scale of 1/2.5 was designed, fabricated and installed by IHI at Oarai Engineering Center of PNC, its pre-operation being accomplished in February 1975. The purpose of SWAT-3 is summarized as follows: (1) To perform an overall test on the safety of Monju's SG and intermediate heat transport system under the design condition against sodium-water reaction accidents. (2) To investigate the damage of the SG structure caused by the sodium-water reaction, and the possibility of repair and recovery operations. The first test was accomplished successfully on June 9, 1975. As a result of the test, the fundamental function of this test facility was proven to be satisfactory as expected. (auth.)

  11. Climate Change and Market Collapse: A Model Applied to Darfur

    Directory of Open Access Journals (Sweden)

    Ola Olsson

    2016-03-01

    Full Text Available A recurring argument in the global debate is that climate deterioration is likely to make social conflicts over diminishing natural resources more common in the future. The exact mechanism behind such a development has so far not been successfully characterized in the literature. In this paper, we present a general model of a community populated by farmers and herders who can either divide up land in a market economy or in autarky. The key insight from our model is that decreasing resources can make trade between the two groups collapse, which in turn makes each group’s welfare independent of that of the other. Predictions from the model are then applied to the conflict in Darfur. Our analysis suggests that three decades of drought in the area can at least partially explain the observed disintegration of markets and the subsequent rise of social tensions.

  12. Liquid-drop model applied to heavy ions irradiation

    International Nuclear Information System (INIS)

    De Cicco, Hernan; Alurralde, Martin A.; Saint-Martin, Maria L. G.; Bernaola, Omar A.

    1999-01-01

    Liquid-drop model is used, previously applied in the study of radiation damage in metals, in an energy range not covered by molecular dynamics, in order to understand experimental data of particle tracks in an organic material (Makrofol E), which cannot be accurately described by the existing theoretical methods. The nuclear and electronic energy depositions are considered for each ion considered and the evolution of the thermal explosion is evaluated. The experimental observation of particle tracks in a region previously considered as 'prohibited' are justified. Although the model used has free parameters and some discrepancies with the experimental diametrical values exist, the agreement obtained is highly superior than that of other existing models. (author)

  13. Linear mixing model applied to AVHRR LAC data

    Science.gov (United States)

    Holben, Brent N.; Shimabukuro, Yosio E.

    1993-01-01

    A linear mixing model was applied to coarse spatial resolution data from the NOAA Advanced Very High Resolution Radiometer. The reflective component of the 3.55 - 3.93 microns channel was extracted and used with the two reflective channels 0.58 - 0.68 microns and 0.725 - 1.1 microns to run a Constraine Least Squares model to generate vegetation, soil, and shade fraction images for an area in the Western region of Brazil. The Landsat Thematic Mapper data covering the Emas National park region was used for estimating the spectral response of the mixture components and for evaluating the mixing model results. The fraction images were compared with an unsupervised classification derived from Landsat TM data acquired on the same day. The relationship between the fraction images and normalized difference vegetation index images show the potential of the unmixing techniques when using coarse resolution data for global studies.

  14. Remote sensing applied to numerical modelling. [water resources pollution

    Science.gov (United States)

    Sengupta, S.; Lee, S. S.; Veziroglu, T. N.; Bland, R.

    1975-01-01

    Progress and remaining difficulties in the construction of predictive mathematical models of large bodies of water as ecosystems are reviewed. Surface temperature is at present the only variable than can be measured accurately and reliably by remote sensing techniques, but satellite infrared data are of sufficient resolution for macro-scale modeling of oceans and large lakes, and airborne radiometers are useful in meso-scale analysis (of lakes, bays, and thermal plumes). Finite-element and finite-difference techniques applied to the solution of relevant coupled time-dependent nonlinear partial differential equations are compared, and the specific problem of the Biscayne Bay and environs ecosystem is tackled in a finite-differences treatment using the rigid-lid model and a rigid-line grid system.

  15. Apply Functional Modelling to Consequence Analysis in Supervision Systems

    DEFF Research Database (Denmark)

    Zhang, Xinxin; Lind, Morten; Gola, Giulio

    2013-01-01

    This paper will first present the purpose and goals of applying functional modelling approach to consequence analysis by adopting Multilevel Flow Modelling (MFM). MFM Models describe a complex system in multiple abstraction levels in both means-end dimension and whole-part dimension. It contains...... consequence analysis to practical or online applications in supervision systems. It will also suggest a multiagent solution as the integration architecture for developing tools to facilitate the utilization results of functional consequence analysis. Finally a prototype of the multiagent reasoning system...... causal relations between functions and goals. A rule base system can be developed to trace the causal relations and perform consequence propagations. This paper will illustrate how to use MFM for consequence reasoning by using rule base technology and describe the challenges for integrating functional...

  16. Applying Probabilistic Decision Models to Clinical Trial Design

    Science.gov (United States)

    Smith, Wade P; Phillips, Mark H

    2018-01-01

    Clinical trial design most often focuses on a single or several related outcomes with corresponding calculations of statistical power. We consider a clinical trial to be a decision problem, often with competing outcomes. Using a current controversy in the treatment of HPV-positive head and neck cancer, we apply several different probabilistic methods to help define the range of outcomes given different possible trial designs. Our model incorporates the uncertainties in the disease process and treatment response and the inhomogeneities in the patient population. Instead of expected utility, we have used a Markov model to calculate quality adjusted life expectancy as a maximization objective. Monte Carlo simulations over realistic ranges of parameters are used to explore different trial scenarios given the possible ranges of parameters. This modeling approach can be used to better inform the initial trial design so that it will more likely achieve clinical relevance.

  17. Applying a Dynamic Resource Supply Model in a Smart Grid

    Directory of Open Access Journals (Sweden)

    Kaiyu Wan

    2014-09-01

    Full Text Available Dynamic resource supply is a complex issue to resolve in a cyber-physical system (CPS. In our previous work, a resource model called the dynamic resource supply model (DRSM has been proposed to handle resources specification, management and allocation in CPS. In this paper, we are integrating the DRSM with service-oriented architecture and applying it to a smart grid (SG, one of the most complex CPS examples. We give the detailed design of the SG for electricity charging request and electricity allocation between plug-in hybrid electric vehicles (PHEV and DRSM through the Android system. In the design, we explain a mechanism for electricity consumption with data collection and re-allocation through ZigBee network. In this design, we verify the correctness of this resource model for expected electricity allocation.

  18. Nature preservation acceptance model applied to tanker oil spill simulations

    DEFF Research Database (Denmark)

    Friis-Hansen, Peter; Ditlevsen, Ove Dalager

    2003-01-01

    is exemplified by a study of oil spills due to simulated tanker collisions in the Danish straits. It is found that the distribution of the oil spill volume per spill is well represented by an exponential distribution both in Oeresund and in Great Belt. When applied in the Poisson model, a risk profile reasonably...... acceptance criterion for the pollution of the environment. This NPWI acceptance criterion is applied to the oil spill example....... be defined in a similar way as the so-called Life Quality Index defined by Nathwani et al [Nathwani JS, Lind NC, Padey MD. Affordable safety by choice: the life quality method. Institute for Risk Research, University of Waterloo; Waterloo (Ontario, Canada):1997], and can be used to quantify the risk...

  19. A Log Logistic Survival Model Applied to Hypobaric Decompression Sickness

    Science.gov (United States)

    Conkin, Johnny

    2001-01-01

    Decompression sickness (DCS) is a complex, multivariable problem. A mathematical description or model of the likelihood of DCS requires a large amount of quality research data, ideas on how to define a decompression dose using physical and physiological variables, and an appropriate analytical approach. It also requires a high-performance computer with specialized software. I have used published DCS data to develop my decompression doses, which are variants of equilibrium expressions for evolved gas plus other explanatory variables. My analytical approach is survival analysis, where the time of DCS occurrence is modeled. My conclusions can be applied to simple hypobaric decompressions - ascents lasting from 5 to 30 minutes - and, after minutes to hours, to denitrogenation (prebreathing). They are also applicable to long or short exposures, and can be used whether the sufferer of DCS is at rest or exercising at altitude. Ultimately I would like my models to be applied to astronauts to reduce the risk of DCS during spacewalks, as well as to future spaceflight crews on the Moon and Mars.

  20. Experimental designs for autoregressive models applied to industrial maintenance

    International Nuclear Information System (INIS)

    Amo-Salas, M.; López-Fidalgo, J.; Pedregal, D.J.

    2015-01-01

    Some time series applications require data which are either expensive or technically difficult to obtain. In such cases scheduling the points in time at which the information should be collected is of paramount importance in order to optimize the resources available. In this paper time series models are studied from a new perspective, consisting in the use of Optimal Experimental Design setup to obtain the best times to take measurements, with the principal aim of saving costs or discarding useless information. The model and the covariance function are expressed in an explicit form to apply the usual techniques of Optimal Experimental Design. Optimal designs for various approaches are computed and their efficiencies are compared. The methods working in an application of industrial maintenance of a critical piece of equipment at a petrochemical plant are shown. This simple model allows explicit calculations in order to show openly the procedure to find the correlation structure, needed for computing the optimal experimental design. In this sense the techniques used in this paper to compute optimal designs may be transferred to other situations following the ideas of the paper, but taking into account the increasing difficulty of the procedure for more complex models. - Highlights: • Optimal experimental design theory is applied to AR models to reduce costs. • The first observation has an important impact on any optimal design. • Either the lack of precision or small starting observations claim for large times. • Reasonable optimal times were obtained relaxing slightly the efficiency. • Optimal designs were computed in a predictive maintenance context

  1. Inverse geothermal modelling applied to Danish sedimentary basins

    Science.gov (United States)

    Poulsen, Søren E.; Balling, Niels; Bording, Thue S.; Mathiesen, Anders; Nielsen, Søren B.

    2017-10-01

    This paper presents a numerical procedure for predicting subsurface temperatures and heat-flow distribution in 3-D using inverse calibration methodology. The procedure is based on a modified version of the groundwater code MODFLOW by taking advantage of the mathematical similarity between confined groundwater flow (Darcy's law) and heat conduction (Fourier's law). Thermal conductivity, heat production and exponential porosity-depth relations are specified separately for the individual geological units of the model domain. The steady-state temperature model includes a model-based transient correction for the long-term palaeoclimatic thermal disturbance of the subsurface temperature regime. Variable model parameters are estimated by inversion of measured borehole temperatures with uncertainties reflecting their quality. The procedure facilitates uncertainty estimation for temperature predictions. The modelling procedure is applied to Danish onshore areas containing deep sedimentary basins. A 3-D voxel-based model, with 14 lithological units from surface to 5000 m depth, was built from digital geological maps derived from combined analyses of reflection seismic lines and borehole information. Matrix thermal conductivity of model lithologies was estimated by inversion of all available deep borehole temperature data and applied together with prescribed background heat flow to derive the 3-D subsurface temperature distribution. Modelled temperatures are found to agree very well with observations. The numerical model was utilized for predicting and contouring temperatures at 2000 and 3000 m depths and for two main geothermal reservoir units, the Gassum (Lower Jurassic-Upper Triassic) and Bunter/Skagerrak (Triassic) reservoirs, both currently utilized for geothermal energy production. Temperature gradients to depths of 2000-3000 m are generally around 25-30 °C km-1, locally up to about 35 °C km-1. Large regions have geothermal reservoirs with characteristic temperatures

  2. Applied economic model development algorithm for electronics company

    Directory of Open Access Journals (Sweden)

    Mikhailov I.

    2017-01-01

    Full Text Available The purpose of this paper is to report about received experience in the field of creating the actual methods and algorithms that help to simplify development of applied decision support systems. It reports about an algorithm, which is a result of two years research and have more than one-year practical verification. In a case of testing electronic components, the time of the contract conclusion is crucial point to make the greatest managerial mistake. At this stage, it is difficult to achieve a realistic assessment of time-limit and of wage-fund for future work. The creation of estimating model is possible way to solve this problem. In the article is represented an algorithm for creation of those models. The algorithm is based on example of the analytical model development that serves for amount of work estimation. The paper lists the algorithm’s stages and explains their meanings with participants’ goals. The implementation of the algorithm have made possible twofold acceleration of these models development and fulfilment of management’s requirements. The resulting models have made a significant economic effect. A new set of tasks was identified to be further theoretical study.

  3. Aplicación del modelo hidrológico SWAT a la cuenca del río Meca (Huelva, España)

    OpenAIRE

    Galván González, Laura; Olías Álvarez, Manuel; Fernández de Villarán San Juan, Rubén; Domingo Santos, Juan Manuel

    2007-01-01

    Acid mine drainage (AMD) is the main pollutant source in the Odiel river basin (SW Spain). Stream-flow data constitute a tool to assess the pollutant load transported by the drainage network, as well as to evaluate the possible impact of restoration measurements along the river. Due to the malfunctioning of the available stream-gauges and in order to sham the Odiel river behavior, a water model is being elaborated using the tool SWAT (Soil and Water Assessment Tool), developed by ...

  4. Comparison of performance of tile drainage routines in SWAT 2009 and 2012 in an extensively tile-drained watershed in the Midwest

    Directory of Open Access Journals (Sweden)

    T. Guo

    2018-01-01

    Full Text Available Subsurface tile drainage systems are widely used in agricultural watersheds in the Midwestern US and enable the Midwest area to become highly productive agricultural lands, but can also create environmental problems, for example nitrate-N contamination associated with drainage waters. The Soil and Water Assessment Tool (SWAT has been used to model watersheds with tile drainage. SWAT2012 revisions 615 and 645 provide new tile drainage routines. However, few studies have used these revisions to study tile drainage impacts at both field and watershed scales. Moreover, SWAT2012 revision 645 improved the soil moisture based curve number calculation method, which has not been fully tested. This study used long-term (1991–2003 field site and river station data from the Little Vermilion River (LVR watershed to evaluate performance of tile drainage routines in SWAT2009 revision 528 (the old routine and SWAT2012 revisions 615 and 645 (the new routine. Both the old and new routines provided reasonable but unsatisfactory (NSE  <  0.5 uncalibrated flow and nitrate loss results for a mildly sloped watershed with low runoff. The calibrated monthly tile flow, surface flow, nitrate-N in tile and surface flow, sediment and annual corn and soybean yield results from SWAT with the old and new tile drainage routines were compared with observed values. Generally, the new routine provided acceptable simulated tile flow (NSE  =  0.48–0.65 and nitrate in tile flow (NSE  =  0.48–0.68 for field sites with random pattern tile and constant tile spacing, while the old routine simulated tile flow and nitrate in tile flow results for the field site with constant tile spacing were unacceptable (NSE  =  0.00–0.32 and −0.29–0.06, respectively. The new modified curve number calculation method in revision 645 (NSE  =  0.50–0.81 better simulated surface runoff than revision 615 (NSE  =  −0.11–0.49. The calibration

  5. Comparison of performance of tile drainage routines in SWAT 2009 and 2012 in an extensively tile-drained watershed in the Midwest

    Science.gov (United States)

    Guo, Tian; Gitau, Margaret; Merwade, Venkatesh; Arnold, Jeffrey; Srinivasan, Raghavan; Hirschi, Michael; Engel, Bernard

    2018-01-01

    Subsurface tile drainage systems are widely used in agricultural watersheds in the Midwestern US and enable the Midwest area to become highly productive agricultural lands, but can also create environmental problems, for example nitrate-N contamination associated with drainage waters. The Soil and Water Assessment Tool (SWAT) has been used to model watersheds with tile drainage. SWAT2012 revisions 615 and 645 provide new tile drainage routines. However, few studies have used these revisions to study tile drainage impacts at both field and watershed scales. Moreover, SWAT2012 revision 645 improved the soil moisture based curve number calculation method, which has not been fully tested. This study used long-term (1991-2003) field site and river station data from the Little Vermilion River (LVR) watershed to evaluate performance of tile drainage routines in SWAT2009 revision 528 (the old routine) and SWAT2012 revisions 615 and 645 (the new routine). Both the old and new routines provided reasonable but unsatisfactory (NSE runoff. The calibrated monthly tile flow, surface flow, nitrate-N in tile and surface flow, sediment and annual corn and soybean yield results from SWAT with the old and new tile drainage routines were compared with observed values. Generally, the new routine provided acceptable simulated tile flow (NSE = 0.48-0.65) and nitrate in tile flow (NSE = 0.48-0.68) for field sites with random pattern tile and constant tile spacing, while the old routine simulated tile flow and nitrate in tile flow results for the field site with constant tile spacing were unacceptable (NSE = 0.00-0.32 and -0.29-0.06, respectively). The new modified curve number calculation method in revision 645 (NSE = 0.50-0.81) better simulated surface runoff than revision 615 (NSE = -0.11-0.49). The calibration provided reasonable parameter sets for the old and new routines in the LVR watershed, and the validation results showed that the new routine has the potential to accurately

  6. Enhanced pid vs model predictive control applied to bldc motor

    Science.gov (United States)

    Gaya, M. S.; Muhammad, Auwal; Aliyu Abdulkadir, Rabiu; Salim, S. N. S.; Madugu, I. S.; Tijjani, Aminu; Aminu Yusuf, Lukman; Dauda Umar, Ibrahim; Khairi, M. T. M.

    2018-01-01

    BrushLess Direct Current (BLDC) motor is a multivariable and highly complex nonlinear system. Variation of internal parameter values with environment or reference signal increases the difficulty in controlling the BLDC effectively. Advanced control strategies (like model predictive control) often have to be integrated to satisfy the control desires. Enhancing or proper tuning of a conventional algorithm results in achieving the desired performance. This paper presents a performance comparison of Enhanced PID and Model Predictive Control (MPC) applied to brushless direct current motor. The simulation results demonstrated that the PSO-PID is slightly better than the PID and MPC in tracking the trajectory of the reference signal. The proposed scheme could be useful algorithms for the system.

  7. Elastic models: a comparative study applied to retinal images.

    Science.gov (United States)

    Karali, E; Lambropoulou, S; Koutsouris, D

    2011-01-01

    In this work various methods of parametric elastic models are compared, namely the classical snake, the gradient vector field snake (GVF snake) and the topology-adaptive snake (t-snake), as well as the method of self-affine mapping system as an alternative to elastic models. We also give a brief overview of the methods used. The self-affine mapping system is implemented using an adapting scheme and minimum distance as optimization criterion, which is more suitable for weak edges detection. All methods are applied to glaucomatic retinal images with the purpose of segmenting the optical disk. The methods are compared in terms of segmentation accuracy and speed, as these are derived from cross-correlation coefficients between real and algorithm extracted contours and segmentation time, respectively. As a result, the method of self-affine mapping system presents adequate segmentation time and segmentation accuracy, and significant independence from initialization.

  8. The challenges of modelling phosphorus in a headwater catchment: Applying a 'limits of acceptability' uncertainty framework to a water quality model

    Science.gov (United States)

    Hollaway, M. J.; Beven, K. J.; Benskin, C. McW. H.; Collins, A. L.; Evans, R.; Falloon, P. D.; Forber, K. J.; Hiscock, K. M.; Kahana, R.; Macleod, C. J. A.; Ockenden, M. C.; Villamizar, M. L.; Wearing, C.; Withers, P. J. A.; Zhou, J. G.; Barber, N. J.; Haygarth, P. M.

    2018-03-01

    There is a need to model and predict the transfer of phosphorus (P) from land to water, but this is challenging because of the large number of complex physical and biogeochemical processes involved. This study presents, for the first time, a 'limits of acceptability' approach of the Generalized Likelihood Uncertainty Estimation (GLUE) framework to the Soil and Water Assessment Tool (SWAT), in an application to a water quality problem in the Newby Beck catchment (12.5 km2), Cumbria, United Kingdom (UK). Using high frequency outlet data (discharge and P), individual evaluation criteria (limits of acceptability) were assigned to observed discharge and P loads for all evaluation time steps, identifying where the model was performing well/poorly and to infer which processes required improvement in the model structure. Initial limits of acceptability were required to be relaxed by a substantial amount (by factors of between 5.3 and 6.7 on a normalized scale depending on the evaluation criteria used) in order to gain a set of behavioral simulations (1001 and 1016, respectively out of 5,000,000). Of the 39 model parameters tested, the representation of subsurface processes and associated parameters, were consistently shown as critical to the model not meeting the evaluation criteria, irrespective of the chosen evaluation metric. It is therefore concluded that SWAT is not an appropriate model to guide P management in this catchment. This approach highlights the importance of high frequency monitoring data for setting robust model evaluation criteria. It also raises the question as to whether it is possible to have sufficient input data available to drive such models so that we can have confidence in their predictions and their ability to inform catchment management strategies to tackle the problem of diffuse pollution from agriculture.

  9. A bidirectional coupling procedure applied to multiscale respiratory modeling

    Energy Technology Data Exchange (ETDEWEB)

    Kuprat, A.P., E-mail: andrew.kuprat@pnnl.gov [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA (United States); Kabilan, S., E-mail: senthil.kabilan@pnnl.gov [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA (United States); Carson, J.P., E-mail: james.carson@pnnl.gov [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA (United States); Corley, R.A., E-mail: rick.corley@pnnl.gov [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA (United States); Einstein, D.R., E-mail: daniel.einstein@pnnl.gov [Fundamental and Computational Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA (United States)

    2013-07-01

    pressure applied to the multiple sets of ODEs. In both the simplified geometry and in the imaging-based geometry, the performance of the method was comparable to that of monolithic schemes, in most cases requiring only a single CFD evaluation per time step. Thus, this new accelerator allows us to begin combining pulmonary CFD models with lower-dimensional models of pulmonary mechanics with little computational overhead. Moreover, because the CFD and lower-dimensional models are totally separate, this framework affords great flexibility in terms of the type and breadth of the adopted lower-dimensional model, allowing the biomedical researcher to appropriately focus on model design. Research funded by the National Heart and Blood Institute Award 1RO1HL073598.

  10. A bidirectional coupling procedure applied to multiscale respiratory modeling

    Science.gov (United States)

    Kuprat, A. P.; Kabilan, S.; Carson, J. P.; Corley, R. A.; Einstein, D. R.

    2013-07-01

    pressure applied to the multiple sets of ODEs. In both the simplified geometry and in the imaging-based geometry, the performance of the method was comparable to that of monolithic schemes, in most cases requiring only a single CFD evaluation per time step. Thus, this new accelerator allows us to begin combining pulmonary CFD models with lower-dimensional models of pulmonary mechanics with little computational overhead. Moreover, because the CFD and lower-dimensional models are totally separate, this framework affords great flexibility in terms of the type and breadth of the adopted lower-dimensional model, allowing the biomedical researcher to appropriately focus on model design. Research funded by the National Heart and Blood Institute Award 1RO1HL073598.

  11. A bidirectional coupling procedure applied to multiscale respiratory modeling

    International Nuclear Information System (INIS)

    Kuprat, A.P.; Kabilan, S.; Carson, J.P.; Corley, R.A.; Einstein, D.R.

    2013-01-01

    pressure applied to the multiple sets of ODEs. In both the simplified geometry and in the imaging-based geometry, the performance of the method was comparable to that of monolithic schemes, in most cases requiring only a single CFD evaluation per time step. Thus, this new accelerator allows us to begin combining pulmonary CFD models with lower-dimensional models of pulmonary mechanics with little computational overhead. Moreover, because the CFD and lower-dimensional models are totally separate, this framework affords great flexibility in terms of the type and breadth of the adopted lower-dimensional model, allowing the biomedical researcher to appropriately focus on model design. Research funded by the National Heart and Blood Institute Award 1RO1HL073598

  12. Risk matrix model applied to the outsourcing of logistics' activities

    Directory of Open Access Journals (Sweden)

    Fouad Jawab

    2015-09-01

    Full Text Available Purpose: This paper proposes the application of the risk matrix model in the field of logistics outsourcing. Such an application can serve as the basis for decision making regarding the conduct of a risk management in the logistics outsourcing process and allow its prevention. Design/methodology/approach: This study is based on the risk management of logistics outsourcing in the field of the retail sector in Morocco. The authors identify all possible risks and then classify and prioritize them using the Risk Matrix Model. Finally, we have come to four possible decisions for the identified risks. The analysis was made possible through interviews and discussions with the heads of departments and agents who are directly involved in each outsourced activity. Findings and Originality/value: It is possible to improve the risk matrix model by proposing more personalized prevention measures according to each company that operates in the mass-market retailing. Originality/value: This study is the only one made in the process of logistics outsourcing in the retail sector in Morocco through Label’vie as a case study. First, we had identified as thorough as we could all possible risks, then we applied the Risk Matrix Model to sort them out in an ascending order of importance and criticality. As a result, we could hand out to the decision-makers the mapping for an effective control of risks and a better guiding of the process of risk management.

  13. Model output statistics applied to wind power prediction

    Energy Technology Data Exchange (ETDEWEB)

    Joensen, A; Giebel, G; Landberg, L [Risoe National Lab., Roskilde (Denmark); Madsen, H; Nielsen, H A [The Technical Univ. of Denmark, Dept. of Mathematical Modelling, Lyngby (Denmark)

    1999-03-01

    Being able to predict the output of a wind farm online for a day or two in advance has significant advantages for utilities, such as better possibility to schedule fossil fuelled power plants and a better position on electricity spot markets. In this paper prediction methods based on Numerical Weather Prediction (NWP) models are considered. The spatial resolution used in NWP models implies that these predictions are not valid locally at a specific wind farm. Furthermore, due to the non-stationary nature and complexity of the processes in the atmosphere, and occasional changes of NWP models, the deviation between the predicted and the measured wind will be time dependent. If observational data is available, and if the deviation between the predictions and the observations exhibits systematic behavior, this should be corrected for; if statistical methods are used, this approaches is usually referred to as MOS (Model Output Statistics). The influence of atmospheric turbulence intensity, topography, prediction horizon length and auto-correlation of wind speed and power is considered, and to take the time-variations into account, adaptive estimation methods are applied. Three estimation techniques are considered and compared, Extended Kalman Filtering, recursive least squares and a new modified recursive least squares algorithm. (au) EU-JOULE-3. 11 refs.

  14. Linear model applied to the evaluation of pharmaceutical stability data

    Directory of Open Access Journals (Sweden)

    Renato Cesar Souza

    2013-09-01

    Full Text Available The expiry date on the packaging of a product gives the consumer the confidence that the product will retain its identity, content, quality and purity throughout the period of validity of the drug. The definition of this term in the pharmaceutical industry is based on stability data obtained during the product registration. By the above, this work aims to apply the linear regression according to the guideline ICH Q1E, 2003, to evaluate some aspects of a product undergoing in a registration phase in Brazil. With this propose, the evaluation was realized with the development center of a multinational company in Brazil, with samples of three different batches composed by two active principal ingredients in two different packages. Based on the preliminary results obtained, it was possible to observe the difference of degradation tendency of the product in two different packages and the relationship between the variables studied, added knowledge so new models of linear equations can be applied and developed for other products.

  15. Ethnobotanical Study of Tehsil Kabal, Swat District, KPK, Pakistan

    Directory of Open Access Journals (Sweden)

    Imtiaz Ahmad

    2011-01-01

    Full Text Available A total of 140 plants have been reported ethnobotanically from Tehsil Kabal, Swat District. These include the 133 plants (95% of angiosperms, 3 (2.14% of gymnosperms, and 2 (1.42% each of pteridophytes and fungi. The largest family is Lamiaceae represented by 11 species followed by Rosaceae represented by 9 species. Among angiosperms 76 (55.63% were herbs, 17 (12.78% were shrubs, and 40 (30.07% were trees; 127 plants (95.48% were dicot while 6 plants (4.51% were monocot. Most of the plants were used for more than one purpose. Generally the plants were used for medicinal, fuel, timber wood, food, and fodder for cattle purposes.

  16. Applying threshold models to donations to a green electricity fund

    International Nuclear Information System (INIS)

    Ito, Nobuyuki; Takeuchi, Kenji; Tsuge, Takahiro; Kishimoto, Atsuo

    2010-01-01

    This study applies a threshold model proposed by to analyze the diffusion process of donating behavior for renewable energy. We first use a stated preference survey to estimate the determinants of a decision to support the donation scheme under various predicted participation rates. Using the estimated coefficients, we simulate how herd behavior spreads and the participation rate reaches the equilibrium. The participation rate at the equilibrium is estimated as 37.88% when the suggested donation is 500 yen, while it is 17.76% when the suggested amount is 1000 yen. The influence of environmentalism and altruism is also examined, and we find that these motivations increase the participation rate by 31.51% on average.

  17. Transient heat conduction in a pebble fuel applying fractional model

    International Nuclear Information System (INIS)

    Gomez A, R.; Espinosa P, G.

    2009-10-01

    In this paper we presents the equation of thermal diffusion of temporary-fractional order in the one-dimensional space in spherical coordinates, with the objective to analyze the heat transference between the fuel and coolant in a fuel element of a Pebble Bed Modular Reactor. The pebble fuel is the heterogeneous system made by microsphere constitutes by U O, pyrolytic carbon and silicon carbide mixed with graphite. To describe the heat transfer phenomena in the pebble fuel we applied a constitutive law fractional (Non-Fourier) in order to analyze the behaviour transient of the temperature distribution in the pebble fuel with anomalous thermal diffusion effects a numerical model is developed. (Author)

  18. Hierarchic stochastic modelling applied to intracellular Ca(2+ signals.

    Directory of Open Access Journals (Sweden)

    Gregor Moenke

    Full Text Available Important biological processes like cell signalling and gene expression have noisy components and are very complex at the same time. Mathematical analysis of such systems has often been limited to the study of isolated subsystems, or approximations are used that are difficult to justify. Here we extend a recently published method (Thurley and Falcke, PNAS 2011 which is formulated in observable system configurations instead of molecular transitions. This reduces the number of system states by several orders of magnitude and avoids fitting of kinetic parameters. The method is applied to Ca(2+ signalling. Ca(2+ is a ubiquitous second messenger transmitting information by stochastic sequences of concentration spikes, which arise by coupling of subcellular Ca(2+ release events (puffs. We derive analytical expressions for a mechanistic Ca(2+ model, based on recent data from live cell imaging, and calculate Ca(2+ spike statistics in dependence on cellular parameters like stimulus strength or number of Ca(2+ channels. The new approach substantiates a generic Ca(2+ model, which is a very convenient way to simulate Ca(2+ spike sequences with correct spiking statistics.

  19. Applying the Expectancy-Value Model to understand health values.

    Science.gov (United States)

    Zhang, Xu-Hao; Xie, Feng; Wee, Hwee-Lin; Thumboo, Julian; Li, Shu-Chuen

    2008-03-01

    Expectancy-Value Model (EVM) is the most structured model in psychology to predict attitudes by measuring attitudinal attributes (AAs) and relevant external variables. Because health value could be categorized as attitude, we aimed to apply EVM to explore its usefulness in explaining variances in health values and investigate underlying factors. Focus group discussion was carried out to identify the most common and significant AAs toward 5 different health states (coded as 11111, 11121, 21221, 32323, and 33333 in EuroQol Five-Dimension (EQ-5D) descriptive system). AAs were measured in a sum of multiplications of subjective probability (expectancy) and perceived value of attributes with 7-point Likert scales. Health values were measured using visual analog scales (VAS, range 0-1). External variables (age, sex, ethnicity, education, housing, marital status, and concurrent chronic diseases) were also incorporated into survey questionnaire distributed by convenience sampling among eligible respondents. Univariate analyses were used to identify external variables causing significant differences in VAS. Multiple linear regression model (MLR) and hierarchical regression model were used to investigate the explanatory power of AAs and possible significant external variable(s) separately or in combination, for each individual health state and a mixed scenario of five states, respectively. Four AAs were identified, namely, "worsening your quality of life in terms of health" (WQoL), "adding a burden to your family" (BTF), "making you less independent" (MLI) and "unable to work or study" (UWS). Data were analyzed based on 232 respondents (mean [SD] age: 27.7 [15.07] years, 49.1% female). Health values varied significantly across 5 health states, ranging from 0.12 (33333) to 0.97 (11111). With no significant external variables identified, EVM explained up to 62% of the variances in health values across 5 health states. The explanatory power of 4 AAs were found to be between 13

  20. Cellular Automata Models Applied to the Study of Landslide Dynamics

    Science.gov (United States)

    Liucci, Luisa; Melelli, Laura; Suteanu, Cristian

    2015-04-01

    Landslides are caused by complex processes controlled by the interaction of numerous factors. Increasing efforts are being made to understand the spatial and temporal evolution of this phenomenon, and the use of remote sensing data is making significant contributions in improving forecast. This paper studies landslides seen as complex dynamic systems, in order to investigate their potential Self Organized Critical (SOC) behavior, and in particular, scale-invariant aspects of processes governing the spatial development of landslides and their temporal evolution, as well as the mechanisms involved in driving the system and keeping it in a critical state. For this purpose, we build Cellular Automata Models, which have been shown to be capable of reproducing the complexity of real world features using a small number of variables and simple rules, thus allowing for the reduction of the number of input parameters commonly used in the study of processes governing landslide evolution, such as those linked to the geomechanical properties of soils. This type of models has already been successfully applied in studying the dynamics of other natural hazards, such as earthquakes and forest fires. The basic structure of the model is composed of three modules: (i) An initialization module, which defines the topographic surface at time zero as a grid of square cells, each described by an altitude value; the surface is acquired from real Digital Elevation Models (DEMs). (ii) A transition function, which defines the rules used by the model to update the state of the system at each iteration. The rules use a stability criterion based on the slope angle and introduce a variable describing the weakening of the material over time, caused for example by rainfall. The weakening brings some sites of the system out of equilibrium thus causing the triggering of landslides, which propagate within the system through local interactions between neighboring cells. By using different rates of

  1. Defining Requirements and Applying Information Modeling for Protecting Enterprise Assets

    Science.gov (United States)

    Fortier, Stephen C.; Volk, Jennifer H.

    The advent of terrorist threats has heightened local, regional, and national governments' interest in emergency response and disaster preparedness. The threat of natural disasters also challenges emergency responders to act swiftly and in a coordinated fashion. When a disaster occurs, an ad hoc coalition of pre-planned groups usually forms to respond to the incident. History has shown that these “system of systems” do not interoperate very well. Communications between fire, police and rescue components either do not work or are inefficient. Government agencies, non-governmental organizations (NGOs), and private industry use a wide array of software platforms for managing data about emergency conditions, resources and response activities. Most of these are stand-alone systems with very limited capability for data sharing with other agencies or other levels of government. Information technology advances have facilitated the movement towards an integrated and coordinated approach to emergency management. Other communication mechanisms, such as video teleconferencing, digital television and radio broadcasting, are being utilized to combat the challenges of emergency information exchange. Recent disasters, such as Hurricane Katrina and the tsunami in Indonesia, have illuminated the weaknesses in emergency response. This paper will discuss the need for defining requirements for components of ad hoc coalitions which are formed to respond to disasters. A goal of our effort was to develop a proof of concept that applying information modeling to the business processes used to protect and mitigate potential loss of an enterprise was feasible. These activities would be modeled both pre- and post-incident.

  2. Applied genre analysis: a multi-perspective model

    Directory of Open Access Journals (Sweden)

    Vijay K Bhatia

    2002-04-01

    Full Text Available Genre analysis can be viewed from two different perspectives: it may be seen as a reflection of the complex realities of the world of institutionalised communication, or it may be seen as a pedagogically effective and convenient tool for the design of language teaching programmes, often situated within simulated contexts of classroom activities. This paper makes an attempt to understand and resolve the tension between these two seemingly contentious perspectives to answer the question: "Is generic description a reflection of reality, or a convenient fiction invented by applied linguists?". The paper also discusses issues related to the nature and use of linguistic description in a genre-based educational enterprise, claiming that instead of using generic descriptions as models for linguistic reproduction of conventional forms to respond to recurring social contexts, as is often the case in many communication based curriculum contexts, they can be used as analytical resource to understand and manipulate complex inter-generic and multicultural realisations of professional discourse, which will enable learners to use generic knowledge to respond to novel social contexts and also to create new forms of discourse to achieve pragmatic success as well as other powerful human agendas.

  3. Applying Quality Function Deployment Model in Burn Unit Service Improvement.

    Science.gov (United States)

    Keshtkaran, Ali; Hashemi, Neda; Kharazmi, Erfan; Abbasi, Mehdi

    2016-01-01

    Quality function deployment (QFD) is one of the most effective quality design tools. This study applies QFD technique to improve the quality of the burn unit services in Ghotbedin Hospital in Shiraz, Iran. First, the patients' expectations of burn unit services and their priorities were determined through Delphi method. Thereafter, burn unit service specifications were determined through Delphi method. Further, the relationships between the patients' expectations and service specifications and also the relationships between service specifications were determined through an expert group's opinion. Last, the final importance scores of service specifications were calculated through simple additive weighting method. The findings show that burn unit patients have 40 expectations in six different areas. These expectations are in 16 priority levels. Burn units also have 45 service specifications in six different areas. There are four-level relationships between the patients' expectations and service specifications and four-level relationships between service specifications. The most important burn unit service specifications have been identified in this study. The QFD model developed in the study can be a general guideline for QFD planners and executives.

  4. Applying Petri nets in modelling the human factor

    International Nuclear Information System (INIS)

    Bedreaga, Luminita; Constntinescu, Cristina; Guzun, Basarab

    2007-01-01

    Usually, in the reliability analysis performed for complex systems, we determine the success probability to work with other performance indices, i.e. the likelihood associated with a given state. The possible values assigned to system states can be derived using inductive methods. If one wants to calculate the probability to occur a particular event in the system, then deductive methods should be applied. In the particular case of the human reliability analysis, as part of probabilistic safety analysis, the international regulatory commission have developed specific guides and procedures to perform such assessments. The paper presents the modality to obtain the human reliability quantification using the Petri nets approach. This is an efficient means to assess reliability systems because of their specific features. The examples showed in the paper are from human reliability documentation without a detailed human factor analysis (qualitative). We present human action modelling using event trees and Petri nets approach. The obtained results by these two kinds of methods are in good concordance. (authors)

  5. Electrodynamic modeling applied to micro-strip gas chambers

    International Nuclear Information System (INIS)

    Fang, R.

    1998-01-01

    Gas gain variations as functions of time, counting rate and substrate resistivity have been observed with Micro-Strip Gas Chambers (MSGC). Such a chamber is here treated as a system of 2 dielectrics, gas and substrate, with finite resistivities. Electric charging between their interface results in variations of the electric field and the gas gain. The electrodynamic equations (including time dependence) for such a system are proposed. A Rule of Charge Accumulation (RCA) is then derived which allows to determine the quantity and sign of charges accumulated on the surface at equilibrium. In order to apply the equations and the rule to MSGCs, a model of gas conductance induced by ionizing radiation is proposed, and a differential equation and some formulae are derived to calculate the rms dispersion and the spatial distribution of electrons (ions) in inhomogeneous electric fields. RCA coupled with a precise simulation of the electric fields gives the first quantitative explanation of gas gain variations of MSGCs. Finally an electrodynamic simulation program is made to reproduce the dynamic process of gain variation due to surface charging with an uncertainty of at most 15% relative to experimental data. As a consequence, the methods for stabilizing operation of MSGCs are proposed. (author)

  6. Hydrological Modeling of the Upper Indus Basin: A Case Study from a High-Altitude Glacierized Catchment Hunza

    Directory of Open Access Journals (Sweden)

    Khan Garee

    2017-01-01

    Full Text Available The Soil andWater Assessment Tool (SWAT model combined with a temperature index and elevation band algorithm was applied to the Hunza watershed, where snow and glacier-melt are the major contributor to river flow. This study’s uniqueness is its use of a snow melt algorithm (temperature index with elevation bands combined with the SWAT, applied to evaluate the performance of the SWAT model in the highly snow and glacier covered watershed of the Upper Indus Basin in response to climate change on future streamflow volume at the outlet of the Hunza watershed, and its contribution to the Indus River System in both space and time, despite its limitation; it is not designed to cover the watershed of heterogeneous mountains. The model was calibrated for the years 1998–2004 and validated for the years 2008–2010. The model performance is evaluated using the four recommended statistical coefficients with uncertainty analysis (p-factor and r-factor. Simulations generated good calibration and validation results for the daily flow gauge. The model efficiency was evaluated, and a strong relationship was observed between the simulated and observed flows. The model results give a coefficient of determination (R2 of 0.82 and a Nash–Sutcliffe Efficiency index (NS of 0.80 for the daily flow with values of p-factor (79% and r-factor (76%. The SWAT model was also used to evaluate climate change impact on hydrological regimes, the target watershed with three GCMs (General Circulation Model of the IPCC fifth report for 2030–2059 and 2070–2099, using 1980–2010 as the control period. Overall, temperature (1.39 C to 6.58 C and precipitation (31% indicated increased variability at the end of the century with increasing river flow (5%–10%; in particular, the analysis showed smaller absolute changes in the hydrology of the study area towards the end of the century. The results revealed that the calibrated model was more sensitive towards temperature and

  7. International Conference on Applied Mathematics, Modeling and Computational Science & Annual meeting of the Canadian Applied and Industrial Mathematics

    CERN Document Server

    Bélair, Jacques; Kunze, Herb; Makarov, Roman; Melnik, Roderick; Spiteri, Raymond J

    2016-01-01

    Focusing on five main groups of interdisciplinary problems, this book covers a wide range of topics in mathematical modeling, computational science and applied mathematics. It presents a wealth of new results in the development of modeling theories and methods, advancing diverse areas of applications and promoting interdisciplinary interactions between mathematicians, scientists, engineers and representatives from other disciplines. The book offers a valuable source of methods, ideas, and tools developed for a variety of disciplines, including the natural and social sciences, medicine, engineering, and technology. Original results are presented on both the fundamental and applied level, accompanied by an ample number of real-world problems and examples emphasizing the interdisciplinary nature and universality of mathematical modeling, and providing an excellent outline of today’s challenges. Mathematical modeling, with applied and computational methods and tools, plays a fundamental role in modern science a...

  8. Applied Research Consultants (ARC): A Vertical Practicum Model of Training Applied Research

    Science.gov (United States)

    Nadler, Joel T.; Cundiff, Nicole L.

    2009-01-01

    The demand for highly trained evaluation consultants is increasing. Furthermore, the gap between job seekers' evaluation competencies and job recruiters' expectations suggests a need for providing practical training experiences. A model using a vertical practicum (advanced students assisting in the training of newer students) is suggested as an…

  9. Novel Multiscale Modeling Tool Applied to Pseudomonas aeruginosa Biofilm Formation

    OpenAIRE

    Biggs, Matthew B.; Papin, Jason A.

    2013-01-01

    Multiscale modeling is used to represent biological systems with increasing frequency and success. Multiscale models are often hybrids of different modeling frameworks and programming languages. We present the MATLAB-NetLogo extension (MatNet) as a novel tool for multiscale modeling. We demonstrate the utility of the tool with a multiscale model of Pseudomonas aeruginosa biofilm formation that incorporates both an agent-based model (ABM) and constraint-based metabolic modeling. The hybrid mod...

  10. Analysis of climate change impact on runoff and sediment delivery in a Great Lake watershed using SWAT

    Science.gov (United States)

    Verma, S.; Bhattarai, R.; Cooke, R.

    2011-12-01

    The green house gas loading of the atmosphere has been increasing since the mid 19th century which threatens to dramatically change the earth's climate in the 21st Century. Scientific evidences show that earth's global average surface temperature has risen some 0.75°C (1.3°F) since 1850. Third Assessment Report (TAR) from the Intergovernmental Panel on Climate Change (IPCC) concluded that human activities have increased the atmospheric concentration of greenhouse gases (GHGs), which will result in a warming world and other changes in the climate. TAR has projected an increase in globally average surface temperature of 1.4 to 5.8 °C and an increase in precipitation of 5 to 20 % over the period of 1990 to 2100. Assuming a global temperature increase of between 2.8 and 5.2 °C, it was estimated a 7-15% increase in global evaporation and precipitation rates. Global warming and subsequent climate change could raise sea level by several tens of centimeters in the next fifty years. Such a rise may erode beaches, worsen coastal flooding and threaten water quality in estuaries and aquifers. With the climate already changing and further change in climate highly likely to happen, study of impact of climate and the adaptation is a necessary component of any response to climate change. The objective of this study is to analyze the impact of climate change on runoff and sediment delivery in a Great Lake watershed located in Northern Ohio. Maumee River watershed is predominantly an agricultural watershed with an area of 6330 sq mile and drains to Lake Erie. Agricultural area covers about 89.9% of the watershed while wooded area covers 7.3%, 1.2% is urban area and other land uses account for 1.6%. Water Quality Laboratory, Heidelberg College has monitored the watershed for last 25 years. The Soil and Water Assessment Tool (SWAT) model is used for both water quantity and water quality simulations for past and future scenarios. SWAT is a continuous, long-term watershed scale

  11. Yield calculation of agricultural non-point source pollutants in Huntai River Basin based on SWAT model%基于SWAT模型的浑太河流域农业面源污染物产生量估算

    Institute of Scientific and Technical Information of China (English)

    付意成; 臧文斌; 董飞; 付敏; 张剑

    2016-01-01

    The establishment of non-point source pollutants output load model under the mode of rainfall-runoff and land use, the analog calculation of agricultural non-point source pollutants in the process of migration and transformation, and the systematic analysis of non-point source pollutants discharge quantity, distribution and composition characteristics are based on actual monitoring data, calibration and validation model, in consideration of underlying surface, hydrology and meteorology, and physical features of Huntai River basin. The areas 1 km away from each side of master stream Huntai River, Taizihe River and Daliaohe River and 5 km away from reservoir were defined as buffer zone, where the mode of land use was transformed so as to restore the natural ecosystem. The process of pollutant migration and conversion was simulated based on the calibration of key hydrological parameters, and the causes as well as the migratory features of non-point source pollution were investigated. The primary area of water environment pollution was mainly distributed along both sides of the water channel of the mainstreams of Huntai River. The point-source pollutant was mainly related to the distribution of industry and the amount of discharged wastewater. The risk of non-point pollution was mainly related to the pattern of agricultural plantation and farmland utilization. The secondary area of water environment pollution was mainly distributed along both sides of the water channel of tributaries. Therefore, the situation of pollutant production corresponding to the intra-regional regulation of industrial structure, land utilization pattern surrounding the water channel should be highlighted. The non-point pollution in Huntai watershed was dominated by farmland pollution, and the main indices of pollutants were total nitrogen (N) and total phosphorus (P). The contribution rate of pollutants was farmland runoff > livestock and poultry breeding > urban runoff > water and soil erosion

  12. Applying Functional Modeling for Accident Management of Nuclear Power Plant

    DEFF Research Database (Denmark)

    Lind, Morten; Zhang, Xinxin

    2014-01-01

    Modeling is given and a detailed presentation of the foundational means-end concepts is presented and the conditions for proper use in modelling accidents are identified. It is shown that Multilevel Flow Modeling can be used for modelling and reasoning about design basis accidents. Its possible role...... for information sharing and decision support in accidents beyond design basis is also indicated. A modelling example demonstrating the application of Multilevel Flow Modelling and reasoning for a PWR LOCA is presented...

  13. Applying Functional Modeling for Accident Management of Nucler Power Plant

    DEFF Research Database (Denmark)

    Lind, Morten; Zhang, Xinxin

    2014-01-01

    Modeling is given and a detailed presentation of the foundational means-end concepts is presented and the conditions for proper use in modelling accidents are identified. It is shown that Multilevel Flow Modeling can be used for modelling and reasoning about design basis accidents. Its possible role...... for information sharing and decision support in accidents beyond design basis is also indicated. A modelling example demonstrating the application of Multilevel Flow Modelling and reasoning for a PWR LOCA is presented....

  14. Object oriented business process modelling in RFID applied computing environment

    NARCIS (Netherlands)

    Zhao, X.; Liu, Chengfei; Lin, T.; Ranasinghe, D.C.; Sheng, Q.Z.

    2010-01-01

    As a tracking technology, Radio Frequency Identification (RFID) is now widely applied to enhance the context awareness of enterprise information systems. Such awareness provides great opportunities to facilitate business process automation and thereby improve operation efficiency and accuracy. With

  15. Experiences in applying Bayesian integrative models in interdisciplinary modeling: the computational and human challenges

    DEFF Research Database (Denmark)

    Kuikka, Sakari; Haapasaari, Päivi Elisabet; Helle, Inari

    2011-01-01

    We review the experience obtained in using integrative Bayesian models in interdisciplinary analysis focusing on sustainable use of marine resources and environmental management tasks. We have applied Bayesian models to both fisheries and environmental risk analysis problems. Bayesian belief...... be time consuming and research projects can be difficult to manage due to unpredictable technical problems related to parameter estimation. Biology, sociology and environmental economics have their own scientific traditions. Bayesian models are becoming traditional tools in fisheries biology, where...

  16. Developing new bacteria subroutines in the SWAT model

    Science.gov (United States)

    Fecal bacteria observations from four different sites in Korea and the US demonstrate seasonal variability, showing a significant relationship with temperature (Figure 1); fecal indicator bacteria (FIB) concentrations are relatively higher in summer and lower in winter , including Stillwater river (...

  17. Model predictive control based on reduced order models applied to belt conveyor system.

    Science.gov (United States)

    Chen, Wei; Li, Xin

    2016-11-01

    In the paper, a model predictive controller based on reduced order model is proposed to control belt conveyor system, which is an electro-mechanics complex system with long visco-elastic body. Firstly, in order to design low-degree controller, the balanced truncation method is used for belt conveyor model reduction. Secondly, MPC algorithm based on reduced order model for belt conveyor system is presented. Because of the error bound between the full-order model and reduced order model, two Kalman state estimators are applied in the control scheme to achieve better system performance. Finally, the simulation experiments are shown that balanced truncation method can significantly reduce the model order with high-accuracy and model predictive control based on reduced-model performs well in controlling the belt conveyor system. Copyright © 2016 ISA. Published by Elsevier Ltd. All rights reserved.

  18. Novel multiscale modeling tool applied to Pseudomonas aeruginosa biofilm formation.

    Directory of Open Access Journals (Sweden)

    Matthew B Biggs

    Full Text Available Multiscale modeling is used to represent biological systems with increasing frequency and success. Multiscale models are often hybrids of different modeling frameworks and programming languages. We present the MATLAB-NetLogo extension (MatNet as a novel tool for multiscale modeling. We demonstrate the utility of the tool with a multiscale model of Pseudomonas aeruginosa biofilm formation that incorporates both an agent-based model (ABM and constraint-based metabolic modeling. The hybrid model correctly recapitulates oxygen-limited biofilm metabolic activity and predicts increased growth rate via anaerobic respiration with the addition of nitrate to the growth media. In addition, a genome-wide survey of metabolic mutants and biofilm formation exemplifies the powerful analyses that are enabled by this computational modeling tool.

  19. Novel multiscale modeling tool applied to Pseudomonas aeruginosa biofilm formation.

    Science.gov (United States)

    Biggs, Matthew B; Papin, Jason A

    2013-01-01

    Multiscale modeling is used to represent biological systems with increasing frequency and success. Multiscale models are often hybrids of different modeling frameworks and programming languages. We present the MATLAB-NetLogo extension (MatNet) as a novel tool for multiscale modeling. We demonstrate the utility of the tool with a multiscale model of Pseudomonas aeruginosa biofilm formation that incorporates both an agent-based model (ABM) and constraint-based metabolic modeling. The hybrid model correctly recapitulates oxygen-limited biofilm metabolic activity and predicts increased growth rate via anaerobic respiration with the addition of nitrate to the growth media. In addition, a genome-wide survey of metabolic mutants and biofilm formation exemplifies the powerful analyses that are enabled by this computational modeling tool.

  20. Empirical modeling and data analysis for engineers and applied scientists

    CERN Document Server

    Pardo, Scott A

    2016-01-01

    This textbook teaches advanced undergraduate and first-year graduate students in Engineering and Applied Sciences to gather and analyze empirical observations (data) in order to aid in making design decisions. While science is about discovery, the primary paradigm of engineering and "applied science" is design. Scientists are in the discovery business and want, in general, to understand the natural world rather than to alter it. In contrast, engineers and applied scientists design products, processes, and solutions to problems. That said, statistics, as a discipline, is mostly oriented toward the discovery paradigm. Young engineers come out of their degree programs having taken courses such as "Statistics for Engineers and Scientists" without any clear idea as to how they can use statistical methods to help them design products or processes. Many seem to think that statistics is only useful for demonstrating that a device or process actually does what it was designed to do. Statistics courses emphasize creati...

  1. A comparison of various modelling approaches applied to Cholera ...

    African Journals Online (AJOL)

    linear models, ARIMA time series modelling, and dynamic regression are ... to certain environmental parameters, and to investigate the feasibility of .... in the SSA literature, the term noise is used to refer to both stochastic noise, as well as.

  2. Comparison of various modelling approaches applied to cholera case data

    CSIR Research Space (South Africa)

    Van Den Bergh, F

    2008-06-01

    Full Text Available cross-wavelet technique, which is used to compute lead times for co-varying variables, and suggests transformations that enhance co-varying behaviour. Several statistical modelling techniques, including generalised linear models, ARIMA time series...

  3. Adequateness of applying the Zmijewski model on Serbian companies

    Directory of Open Access Journals (Sweden)

    Pavlović Vladan

    2012-12-01

    Full Text Available The aim of the paper is to determine the accuracy of the prediction of Zmijewski model in Serbia on the eligible sample. At the same time, the paper identifies model's strengths, weaknesses and limitations of its possible application. Bearing in mind that the economic environment in Serbia is not similar to the United States at the time the model was developed, Zmijewski model is surprisingly accurate in the case of Serbian companies. The accuracy was slightly weaker than the model results in the U.S. in its original form, but much better than the results model gave in the U.S. in the period 1988-1991, and 1992-1999. Model gave also better results in Serbia comparing those in Croatia, even in Croatia model was adjusted.

  4. Comparison of two anisotropic layer models applied to induction motors

    NARCIS (Netherlands)

    Sprangers, R.L.J.; Paulides, J.J.H.; Boynov, K.O.; Waarma, J.; Lomonova, E.

    2013-01-01

    A general description of the Anisotropic Layer Theory, derived in the polar coordinate system, and applied to the analysis of squirrel-cage induction motors (IMs), is presented. The theory considers non-conductive layers, layer with predefined current density and layers with induced current density.

  5. Applying the Job Characteristics Model to the College Education Experience

    Science.gov (United States)

    Kass, Steven J.; Vodanovich, Stephen J.; Khosravi, Jasmine Y.

    2011-01-01

    Boredom is one of the most common complaints among university students, with studies suggesting its link to poor grades, drop out, and behavioral problems. Principles borrowed from industrial-organizational psychology may help prevent boredom and enrich the classroom experience. In the current study, we applied the core dimensions of the job…

  6. Process Modeling Applied to Metal Forming and Thermomechanical Processing

    Science.gov (United States)

    1984-09-01

    measured (Lloyd & Kenny, 1982 and Kohara & Katsuta, 1978), The interpretation of these relations are qualitative at this stage (Lloyd et al. (1978...34, Applied Science Publishers, London l.elly,P.N. (1971) J . Aus t . Ins t .Me t a 1 s , 1_6, 104. Kohara , S. and Katsuta, M. (1978) J . Ja p . In

  7. Comparison of two anisotropic layer models applied to induction motors

    NARCIS (Netherlands)

    Sprangers, R.L.J.; Paulides, J.J.H.; Boynov, K.O.; Lomonova, E.A.; Waarma, J.

    2014-01-01

    A general description of the Anisotropic Layer Theory, derived in the polar coordinate system, and applied to the analysis of squirrel-cage induction motors (IMs), is presented. The theory considers non-conductive layers, layer with predefined current density and layers with induced current density.

  8. Applying Functional Modeling for Accident Management of Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lind, Morten; Zhang Xinxin [Harbin Engineering University, Harbin (China)

    2014-08-15

    The paper investigate applications of functional modeling for accident management in complex industrial plant with special reference to nuclear power production. Main applications for information sharing among decision makers and decision support are identified. An overview of Multilevel Flow Modeling is given and a detailed presentation of the foundational means-end concepts is presented and the conditions for proper use in modelling accidents are identified. It is shown that Multilevel Flow Modeling can be used for modelling and reasoning about design basis accidents. Its possible role for information sharing and decision support in accidents beyond design basis is also indicated. A modelling example demonstrating the application of Multilevel Flow Modelling and reasoning for a PWR LOCA is presented.

  9. Applying Model Checking to Industrial-Sized PLC Programs

    CERN Document Server

    AUTHOR|(CDS)2079190; Darvas, Daniel; Blanco Vinuela, Enrique; Tournier, Jean-Charles; Bliudze, Simon; Blech, Jan Olaf; Gonzalez Suarez, Victor M

    2015-01-01

    Programmable logic controllers (PLCs) are embedded computers widely used in industrial control systems. Ensuring that a PLC software complies with its specification is a challenging task. Formal verification has become a recommended practice to ensure the correctness of safety-critical software but is still underused in industry due to the complexity of building and managing formal models of real applications. In this paper, we propose a general methodology to perform automated model checking of complex properties expressed in temporal logics (\\eg CTL, LTL) on PLC programs. This methodology is based on an intermediate model (IM), meant to transform PLC programs written in various standard languages (ST, SFC, etc.) to different modeling languages of verification tools. We present the syntax and semantics of the IM and the transformation rules of the ST and SFC languages to the nuXmv model checker passing through the intermediate model. Finally, two real cases studies of \\CERN PLC programs, written mainly in th...

  10. Polarimetric SAR interferometry applied to land ice: modeling

    DEFF Research Database (Denmark)

    Dall, Jørgen; Papathanassiou, Konstantinos; Skriver, Henning

    2004-01-01

    This paper introduces a few simple scattering models intended for the application of polarimetric SAR interfer-ometry to land ice. The principal aim is to eliminate the penetration bias hampering ice sheet elevation maps generated with single-channel SAR interferometry. The polarimetric coherent...... scattering models are similar to the oriented-volume model and the random-volume-over-ground model used in vegetation studies, but the ice models are adapted to the different geometry of land ice. Also, due to compaction, land ice is not uniform; a fact that must be taken into account for large penetration...... depths. The validity of the scattering models is examined using L-band polarimetric interferometric SAR data acquired with the EMISAR system over an ice cap located in the percolation zone of the Greenland ice sheet. Radar reflectors were deployed on the ice surface prior to the data acquisition in order...

  11. Applied exposure modeling for residual radioactivity and release criteria

    International Nuclear Information System (INIS)

    Lee, D.W.

    1989-01-01

    The protection of public health and the environment from the release of materials with residual radioactivity for recycle or disposal as wastes without radioactive contents of concern presents a formidable challenge. Existing regulatory criteria are based on technical judgment concerning detectability and simple modeling. Recently, exposure modeling methodologies have been developed to provide a more consistent level of health protection. Release criteria derived from the application of exposure modeling methodologies share the same basic elements of analysis but are developed to serve a variety of purposes. Models for the support of regulations for all applications rely on conservative interpretations of generalized conditions while models developed to show compliance incorporate specific conditions not likely to be duplicated at other sites. Research models represent yet another type of modeling which strives to simulate the actual behavior of released material. In spite of these differing purposes, exposure modeling permits the application of sound and reasoned principles of radiation protection to the release of materials with residual levels of radioactivity. Examples of the similarities and differences of these models are presented and an application to the disposal of materials with residual levels of uranium contamination is discussed. 5 refs., 2 tabs

  12. Transforming Collaborative Process Models into Interface Process Models by Applying an MDA Approach

    Science.gov (United States)

    Lazarte, Ivanna M.; Chiotti, Omar; Villarreal, Pablo D.

    Collaborative business models among enterprises require defining collaborative business processes. Enterprises implement B2B collaborations to execute these processes. In B2B collaborations the integration and interoperability of processes and systems of the enterprises are required to support the execution of collaborative processes. From a collaborative process model, which describes the global view of the enterprise interactions, each enterprise must define the interface process that represents the role it performs in the collaborative process in order to implement the process in a Business Process Management System. Hence, in this work we propose a method for the automatic generation of the interface process model of each enterprise from a collaborative process model. This method is based on a Model-Driven Architecture to transform collaborative process models into interface process models. By applying this method, interface processes are guaranteed to be interoperable and defined according to a collaborative process.

  13. Applying Hierarchical Model Calibration to Automatically Generated Items.

    Science.gov (United States)

    Williamson, David M.; Johnson, Matthew S.; Sinharay, Sandip; Bejar, Isaac I.

    This study explored the application of hierarchical model calibration as a means of reducing, if not eliminating, the need for pretesting of automatically generated items from a common item model prior to operational use. Ultimately the successful development of automatic item generation (AIG) systems capable of producing items with highly similar…

  14. Surface-bounded growth modeling applied to human mandibles

    DEFF Research Database (Denmark)

    Andresen, Per Rønsholt; Brookstein, F. L.; Conradsen, Knut

    2000-01-01

    From a set of longitudinal three-dimensional scans of the same anatomical structure, the authors have accurately modeled the temporal shape and size changes using a linear shape model. On a total of 31 computed tomography scans of the mandible from six patients, 14,851 semilandmarks are found...

  15. An electricity billing model | Adetona | Journal of Applied Science ...

    African Journals Online (AJOL)

    Linear regression analysis has been employed to develop a model for predicting accurately the electricity billing for commercial consumers in Ogun State (Nigeria) at faster rate. The electricity billing model was implement-ed, executed and tested using embedded MATLAB function blocks. The correlations between the ...

  16. Geographically Weighted Logistic Regression Applied to Credit Scoring Models

    Directory of Open Access Journals (Sweden)

    Pedro Henrique Melo Albuquerque

    Full Text Available Abstract This study used real data from a Brazilian financial institution on transactions involving Consumer Direct Credit (CDC, granted to clients residing in the Distrito Federal (DF, to construct credit scoring models via Logistic Regression and Geographically Weighted Logistic Regression (GWLR techniques. The aims were: to verify whether the factors that influence credit risk differ according to the borrower’s geographic location; to compare the set of models estimated via GWLR with the global model estimated via Logistic Regression, in terms of predictive power and financial losses for the institution; and to verify the viability of using the GWLR technique to develop credit scoring models. The metrics used to compare the models developed via the two techniques were the AICc informational criterion, the accuracy of the models, the percentage of false positives, the sum of the value of false positive debt, and the expected monetary value of portfolio default compared with the monetary value of defaults observed. The models estimated for each region in the DF were distinct in their variables and coefficients (parameters, with it being concluded that credit risk was influenced differently in each region in the study. The Logistic Regression and GWLR methodologies presented very close results, in terms of predictive power and financial losses for the institution, and the study demonstrated viability in using the GWLR technique to develop credit scoring models for the target population in the study.

  17. Nonstandard Finite Difference Method Applied to a Linear Pharmacokinetics Model

    Directory of Open Access Journals (Sweden)

    Oluwaseun Egbelowo

    2017-05-01

    Full Text Available We extend the nonstandard finite difference method of solution to the study of pharmacokinetic–pharmacodynamic models. Pharmacokinetic (PK models are commonly used to predict drug concentrations that drive controlled intravenous (I.V. transfers (or infusion and oral transfers while pharmacokinetic and pharmacodynamic (PD interaction models are used to provide predictions of drug concentrations affecting the response of these clinical drugs. We structure a nonstandard finite difference (NSFD scheme for the relevant system of equations which models this pharamcokinetic process. We compare the results obtained to standard methods. The scheme is dynamically consistent and reliable in replicating complex dynamic properties of the relevant continuous models for varying step sizes. This study provides assistance in understanding the long-term behavior of the drug in the system, and validation of the efficiency of the nonstandard finite difference scheme as the method of choice.

  18. Evapotranspiration management based on the application of SWAT for balancing water consumption: A case study in Guantao, China

    Science.gov (United States)

    Liu, Bin; Gan, Hong

    2018-06-01

    Rapid social and economic development results in increased demand for water resources. This can lead to the unsustainable development and exploitation of water resources which in turn causes significant environmental problems. Conventional water resource management approaches, such as supply and demand management strategies, frequently fail to restore regional water balance. This paper introduces the concept of water consumption balance, the balance between actual evapotranspiration (ET) and target ET, and establishes a framework to realize regional water balance. The framework consists of three stages: (1) determination of target ET and actual ET; (2) quantification of the water-saving requirements for the region; and (3) reduction of actual ET by implementing various water saving management strategies. Using this framework, a case study was conducted for Guantao County, China. The SWAT model was utilized to aid in the selection of the best water saving management strategy by comparing the ET of different irrigation methods and crop pattern adjustments. Simulation results revealed that determination of SWAT model parameters using remote sensing ET is feasible and that the model is a valuable tool for ET management. Irrigation was found to have a greater influence on the ET of winter wheat as compared to that of maize, indicating that reduction in winter wheat cultivation is the most effective way to reduce regional ET. However, the effect of water-saving irrigation methods on the reduction of ET was not obvious. This indicates that it would be difficult to achieve regional ET reduction using water-saving irrigation methods only. Furthermore, selecting the best water saving management strategy by relying solely on the amount of reduced ET was insufficient, because it ignored the impact of water conservation measures on the livelihood of the agricultural community. Incorporating these considerations with our findings, we recommend changing the current irrigation

  19. Watershed modeling tools and data for prognostic and diagnostic

    Science.gov (United States)

    Chambel-Leitao, P.; Brito, D.; Neves, R.

    2009-04-01

    's widely used in the world. Watershed models can be characterized by the high number of processes associated simulated. The estimation of these processes is also data intensive, requiring data on topography, land use / land cover, agriculture practices, soil type, precipitation, temperature, relative humidity, wind and radiation. Every year new data is being made available namely by satellite, that has allow to improve the quality of model input and also the calibration of the models (Galvão et. al, 2004b). Tools to cope with the vast amount of data have been developed: data formatting, data retrieving, data bases, metadata bases. The high number of processes simulated in watershed models makes them very wide in terms of output. The SWAT model outputs were modified to produce MOHID compliant result files (time series and HDF). These changes maintained the integrity of the original model, thus guarantying that results remain equal to the original version of SWAT. This allowed to output results in MOHID format, thus making it possible to immediately process it with MOHID visualization and data analysis tools (Chambel-Leitão et. al 2007; Trancoso et. al, 2009). Besides SWAT was modified to produce results files in HDF5 format, this allows the visualization of watershed properties (modeled by SWAT) in animated maps using MOHID GIS. The modified version of SWAT described here has been applied to various national and European projects. Results of the application of this modified version of SWAT to estimate hydrology and nutrients loads to estuaries and water bodies will be shown (Chambel-Leitão, 2008; Yarrow & Chambel-Leitão 2008; Chambel-Leitão et. al 2008; Yarrow & P. Chambel-Leitão, 2007; Yarrow & P. Chambel-Leitão, 2007; Coelho et. al., 2008). Keywords: Watershed models, SWAT, MOHID LAND, Hydrology, Nutrient Loads Arnold, J. G. and Fohrer, N. (2005). SWAT2000: current capabilities and research opportunities in applied watershed modeling. Hydrol. Process. 19, 563

  20. The Cheshire Cat principle applied to hybrid bag models

    International Nuclear Information System (INIS)

    Nielsen, H.B.; Wirzba, A.

    1987-05-01

    Here is argued for the Cheshire Cat point of view according to which the bag (itself) has only notational, but no physical significance. It is explained in a 1+1 dimensional exact Cheshire Cat model how a fermion can escape from the bag by means of an anomaly. We also suggest that suitably constructed hybrid bag models may be used to fix such parameters of effective Lagrangians that can otherwise be obtained from experiments only. This idea is illustrated in a calculation of the mass of the pseudoscalar η' meson in 1+1 dimension. Thus there is hope to find a construction principle for a phenomenologically sensible model. (orig.)

  1. Trailing edge noise model applied to wind turbine airfoils

    Energy Technology Data Exchange (ETDEWEB)

    Bertagnolio, F.

    2008-01-15

    The aim of this work is firstly to provide a quick introduction to the theory of noise generation that are relevant to wind turbine technology with focus on trailing edge noise. Secondly, the socalled TNO trailing edge noise model developed by Parchen [1] is described in more details. The model is tested and validated by comparing with other results from the literature. Finally, this model is used in the optimization process of two reference airfoils in order to reduce their noise signature: the RISOE-B1-18 and the S809 airfoils. (au)

  2. Environmental gamma radiation measurement in District Swat (Pakistan))

    International Nuclear Information System (INIS)

    Jabbar, T.; Khan, K.; Akhter, P.; Jabbar, A.; Subhani, M.S.

    2008-01-01

    External exposure to environmental gamma ray sources is an important component of exposure to the public. A survey was carried out to determine activity concentration levels and associated doses from 226 Ra, 232 Th, 40 K and 137 Cs by means of high-resolution gamma ray spectrometry in the Swat district, famous for tourism. The mean concentrations for 226 Ra, 232 Th and 40 K were found to be 50.4 ± 0.7, 34.8 ± 0.7 and 434.5 ± 7.4 Bq kg -1 , respectively, in soil samples, which are slightly more than the world average values. However, 137 Cs was only found in the soil sample of Barikot with an activity concentration of 34 ± 1.2 Bq kg -1 . Only 40 K was determined in vegetation samples with an average activity of 172.2 ± 1.7 Bq kg -1 , whereas in water samples, all radionuclides were found below lower limits of detection. The radium equivalent activity in all soil samples is lower than the limit set in the Organisation for Economic Cooperation and Development report (370 Bq kg -1 ). The value of the external exposure dose has been determined from the content of these radionuclides in soil. The average terrestrial gamma air absorbed dose rate was observed to be 62.4 nGy h -1 , which yields an annual effective dose of 0.08 mSv. The average value of the annual effective dose lies close to the global range of outdoor radiation exposure given in United Nations Scientific Committee on the Effects of Atomic Radiation. However, the main component of the radiation dose to the population residing in the study area arises from cosmic ray due to high altitude. (authors)

  3. Lecturing and Loving It: Applying the Information-Processing Model.

    Science.gov (United States)

    Parker, Jonathan K.

    1993-01-01

    Discusses the benefits of lecturing, when done properly, in high schools. Describes the positive attributes of effective lecturers. Provides a human information-processing model applicable to the task of lecturing to students. (HB)

  4. Hydrodynamics and water quality models applied to Sepetiba Bay

    Science.gov (United States)

    Cunha, Cynara de L. da N.; Rosman, Paulo C. C.; Ferreira, Aldo Pacheco; Carlos do Nascimento Monteiro, Teófilo

    2006-10-01

    A coupled hydrodynamic and water quality model is used to simulate the pollution in Sepetiba Bay due to sewage effluent. Sepetiba Bay has a complicated geometry and bottom topography, and is located on the Brazilian coast near Rio de Janeiro. In the simulation, the dissolved oxygen (DO) concentration and biochemical oxygen demand (BOD) are used as indicators for the presence of organic matter in the body of water, and as parameters for evaluating the environmental pollution of the eastern part of Sepetiba Bay. Effluent sources in the model are taken from DO and BOD field measurements. The simulation results are consistent with field observations and demonstrate that the model has been correctly calibrated. The model is suitable for evaluating the environmental impact of sewage effluent on Sepetiba Bay from river inflows, assessing the feasibility of different treatment schemes, and developing specific monitoring activities. This approach has general applicability for environmental assessment of complicated coastal bays.

  5. A Model-Based Prognostics Approach Applied to Pneumatic Valves

    Data.gov (United States)

    National Aeronautics and Space Administration — Within the area of systems health management, the task of prognostics centers on predicting when components will fail. Model-based prognostics exploits domain...

  6. A Model-based Prognostics Approach Applied to Pneumatic Valves

    Data.gov (United States)

    National Aeronautics and Space Administration — Within the area of systems health management, the task of prognostics centers on predicting when components will fail. Model-based prognostics exploits domain...

  7. Applying Time Series Analysis Model to Temperature Data in Greenhouses

    Directory of Open Access Journals (Sweden)

    Abdelhafid Hasni

    2011-03-01

    Full Text Available The objective of the research is to find an appropriate Seasonal Auto-Regressive Integrated Moving Average (SARIMA Model for fitting the inside air temperature (Tin of a naturally ventilated greenhouse under Mediterranean conditions by considering the minimum of Akaike Information Criterion (AIC. The results of fitting were as follows: the best SARIMA Model for fitting air temperature of greenhouse is SARIMA (1,0,0 (1,0,224.

  8. The J3 SCR model applied to resonant converter simulation

    Science.gov (United States)

    Avant, R. L.; Lee, F. C. Y.

    1985-01-01

    The J3 SCR model is a continuous topology computer model for the SCR. Its circuit analog and parameter estimation procedure are uniformly applicable to popular computer-aided design and analysis programs such as SPICE2 and SCEPTRE. The circuit analog is based on the intrinsic three pn junction structure of the SCR. The parameter estimation procedure requires only manufacturer's specification sheet quantities as a data base.

  9. Agent-Based Modelling applied to 5D model of the HIV infection

    Directory of Open Access Journals (Sweden)

    Toufik Laroum

    2016-12-01

    The simplest model was the 3D mathematical model. But the complexity of this phenomenon and the diversity of cells and actors which affect its evolution requires the use of new approaches such as multi-agents approach that we have applied in this paper. The results of our simulator on the 5D model are promising because they are consistent with biological knowledge’s. Therefore, the proposed approach is well appropriate to the study of population dynamics in general and could help to understand and predict the dynamics of HIV infection.

  10. GIS-Based Population Model Applied to Nevada Transportation Routes

    International Nuclear Information System (INIS)

    Mills, G.S.; Neuhauser, K.S.

    1999-01-01

    Recently, a model based on geographic information system (GIS) processing of US Census Block data has made high-resolution population analysis for transportation risk analysis technically and economically feasible. Population density bordering each kilometer of a route may be tabulated with specific route sections falling into each of three categories (Rural, Suburban or Urban) identified for separate risk analysis. In addition to the improvement in resolution of Urban areas along a route, the model provides a statistically-based correction to population densities in Rural and Suburban areas where Census Block dimensions may greatly exceed the 800-meter scale of interest. A semi-automated application of the GIS model to a subset of routes in Nevada (related to the Yucca Mountain project) are presented, and the results compared to previous models including a model based on published Census and other data. These comparisons demonstrate that meaningful improvement in accuracy and specificity of transportation risk analyses is dependent on correspondingly accurate and geographically-specific population density data

  11. Applying Four Different Risk Models in Local Ore Selection

    International Nuclear Information System (INIS)

    Richmond, Andrew

    2002-01-01

    Given the uncertainty in grade at a mine location, a financially risk-averse decision-maker may prefer to incorporate this uncertainty into the ore selection process. A FORTRAN program risksel is presented to calculate local risk-adjusted optimal ore selections using a negative exponential utility function and three dominance models: mean-variance, mean-downside risk, and stochastic dominance. All four methods are demonstrated in a grade control environment. In the case study, optimal selections range with the magnitude of financial risk that a decision-maker is prepared to accept. Except for the stochastic dominance method, the risk models reassign material from higher cost to lower cost processing options as the aversion to financial risk increases. The stochastic dominance model usually was unable to determine the optimal local selection

  12. Hidden multidimensional social structure modeling applied to biased social perception

    Science.gov (United States)

    Maletić, Slobodan; Zhao, Yi

    2018-02-01

    Intricacies of the structure of social relations are realized by representing a collection of overlapping opinions as a simplicial complex, thus building latent multidimensional structures, through which agents are, virtually, moving as they exchange opinions. The influence of opinion space structure on the distribution of opinions is demonstrated by modeling consensus phenomena when the opinion exchange between individuals may be affected by the false consensus effect. The results indicate that in the cases with and without bias, the road toward consensus is influenced by the structure of multidimensional space of opinions, and in the biased case, complete consensus is achieved. The applications of proposed modeling framework can easily be generalized, as they transcend opinion formation modeling.

  13. Differential Evolution algorithm applied to FSW model calibration

    Science.gov (United States)

    Idagawa, H. S.; Santos, T. F. A.; Ramirez, A. J.

    2014-03-01

    Friction Stir Welding (FSW) is a solid state welding process that can be modelled using a Computational Fluid Dynamics (CFD) approach. These models use adjustable parameters to control the heat transfer and the heat input to the weld. These parameters are used to calibrate the model and they are generally determined using the conventional trial and error approach. Since this method is not very efficient, we used the Differential Evolution (DE) algorithm to successfully determine these parameters. In order to improve the success rate and to reduce the computational cost of the method, this work studied different characteristics of the DE algorithm, such as the evolution strategy, the objective function, the mutation scaling factor and the crossover rate. The DE algorithm was tested using a friction stir weld performed on a UNS S32205 Duplex Stainless Steel.

  14. Modeling the microstructure of surface by applying BRDF function

    Science.gov (United States)

    Plachta, Kamil

    2017-06-01

    The paper presents the modeling of surface microstructure using a bidirectional reflectance distribution function. This function contains full information about the reflectance properties of the flat surfaces - it is possible to determine the share of the specular, directional and diffuse components in the reflected luminous stream. The software is based on the authorial algorithm that uses selected elements of this function models, which allows to determine the share of each component. Basing on obtained data, the surface microstructure of each material can be modeled, which allows to determine the properties of this materials. The concentrator directs the reflected solar radiation onto the photovoltaic surface, increasing, at the same time, the value of the incident luminous stream. The paper presents an analysis of selected materials that can be used to construct the solar concentrator system. The use of concentrator increases the power output of the photovoltaic system by up to 17% as compared to the standard solution.

  15. Computational modeling applied to stress gradient analysis for metallic alloys

    International Nuclear Information System (INIS)

    Iglesias, Susana M.; Assis, Joaquim T. de; Monine, Vladimir I.

    2009-01-01

    Nowadays composite materials including materials reinforced by particles are the center of the researcher's attention. There are problems with the stress measurements in these materials, connected with the superficial stress gradient caused by the difference of the stress state of particles on the surface and in the matrix of the composite material. Computer simulation of diffraction profile formed by superficial layers of material allows simulate the diffraction experiment and gives the possibility to resolve the problem of stress measurements when the stress state is characterized by strong gradient. The aim of this paper is the application of computer simulation technique, initially developed for homogeneous materials, for diffraction line simulation of composite materials and alloys. Specifically we applied this technique for siluminum fabricated by powder metallurgy. (author)

  16. Gordon's model applied to nursing care of people with depression.

    Science.gov (United States)

    Temel, M; Kutlu, F Y

    2015-12-01

    Psychiatric nurses should consider the patient's biological, psychological and social aspects. Marjory Gordon's Functional Health Pattern Model ensures a holistic approach for the patient. To examine the effectiveness of Gordon's Functional Health Pattern Model in reducing depressive symptoms, increasing self-efficacy, coping with depression and increasing hope in people with depression. A quasi-experimental two-group pre-test and post-test design was adopted. Data were collected from April 2013 to May 2014 from people with depression at the psychiatry clinic of a state hospital in Turkey; they were assigned to the intervention (n = 34) or control group (n = 34). The intervention group received nursing care according to Gordon's Functional Health Pattern Model and routine care, while the control group received routine care only. The Beck Depression Inventory, Beck Hopelessness Scale and Depression Coping Self-Efficacy Scale were used. The intervention group had significantly lower scores on the Beck Depression Inventory and Beck Hopelessness Scale at the post-test and 3-month follow-up; they had higher scores on the Depression Coping Self-Efficacy Scale at the 3-month follow-up when compared with the control group. The study was conducted at only one psychiatry clinic. The intervention and control group patients were at the clinic at the same time and influenced each other. Moreover, because clinical routines were in progress during the study, the results cannot only be attributed to nursing interventions. Nursing models offer guidance for the care provided. Practices based on the models return more efficient and systematic caregiving results with fewer health problems. Gordon's Functional Health Pattern Model was effective in improving the health of people with depression and could be introduced as routine care with ongoing evaluation in psychiatric clinics. More research is needed to evaluate Gordon's Nursing Model effect on people with depression. Future

  17. Applying an Employee-Motivation Model to Prevent Student Plagiarism.

    Science.gov (United States)

    Malouff, John M.; Sims, Randi L.

    1996-01-01

    A model based on Vroom's expectancy theory of employee motivation posits that instructors can prevent plagiarism by ensuring that students understand the rules of ethical writing, expect assignments to be manageable and have personal benefits, and expect plagiarism to be difficult and have important personal costs. (SK)

  18. Applying the knowledge creation model to the management of ...

    African Journals Online (AJOL)

    In present-day society, the need to manage indigenous knowledge is widely recognised. However, there is a debate in progress on whether or not indigenous knowledge can be easily managed. The purpose of this paper is to examine the possibility of using knowledge management models like knowledge creation theory ...

  19. Robust model identification applied to type 1diabetes

    DEFF Research Database (Denmark)

    Finan, Daniel Aaron; Jørgensen, John Bagterp; Poulsen, Niels Kjølstad

    2010-01-01

    In many realistic applications, process noise is known to be neither white nor normally distributed. When identifying models in these cases, it may be more effective to minimize a different penalty function than the standard sum of squared errors (as in a least-squares identification method). Thi...

  20. Dynamics Model Applied to Pricing Options with Uncertain Volatility

    Directory of Open Access Journals (Sweden)

    Lorella Fatone

    2012-01-01

    model is proposed. The data used to test the calibration problem included observations of asset prices over a finite set of (known equispaced discrete time values. Statistical tests were used to estimate the statistical significance of the two parameters of the Black-Scholes model: the volatility and the drift. The effects of these estimates on the option pricing problem were investigated. In particular, the pricing of an option with uncertain volatility in the Black-Scholes framework was revisited, and a statistical significance was associated with the price intervals determined using the Black-Scholes-Barenblatt equations. Numerical experiments involving synthetic and real data were presented. The real data considered were the daily closing values of the S&P500 index and the associated European call and put option prices in the year 2005. The method proposed here for calibrating the Black-Scholes dynamics model could be extended to other science and engineering models that may be expressed in terms of stochastic dynamical systems.

  1. Modular Modelling and Simulation Approach - Applied to Refrigeration Systems

    DEFF Research Database (Denmark)

    Sørensen, Kresten Kjær; Stoustrup, Jakob

    2008-01-01

    This paper presents an approach to modelling and simulation of the thermal dynamics of a refrigeration system, specifically a reefer container. A modular approach is used and the objective is to increase the speed and flexibility of the developed simulation environment. The refrigeration system...

  2. A comparison of various modelling approaches applied to Cholera ...

    African Journals Online (AJOL)

    The analyses are demonstrated on data collected from Beira, Mozambique. Dynamic regression was found to be the preferred forecasting method for this data set. Keywords:Cholera, modelling, signal processing, dynamic regression, negative binomial regression, wavelet analysis, cross-wavelet analysis. ORiON Vol.

  3. Leadership Identity Development: Challenges in Applying a Developmental Model

    Science.gov (United States)

    Komives, Susan R.; Longerbeam, Susan D.; Mainella, Felicia; Osteen, Laura; Owen, Julie E.; Wagner, Wendy

    2009-01-01

    The leadership identity development (LID) grounded theory (Komives, Owen, Longerbeam, Mainella, & Osteen, 2005) and related LID model (Komives, Longerbeam, Owen, Mainella, & Osteen, 2006) present a framework for understanding how individual college students develop the social identity of being collaborative, relational leaders…

  4. Applying the elastic model for various nucleus-nucleus fusion

    International Nuclear Information System (INIS)

    HASSAN, G.S.; RAGAB, H.S.; SEDDEEK, M.K.

    2000-01-01

    The Elastic Model of two free parameters m,d given by Scalia has been used for wider energy regions to fit the available experimental data for potential barriers and cross sections. In order to generalize Scalia's formula in both sub- and above-barrier regions, we calculated m, d for pairs rather than those given by Scalia and compared the calculated cross sections with the experimental data. This makes a generalization of the Elastic Model in describing fusion process. On the other hand, Scalia's range of interacting systems was 24 ≤ A ≤194 where A is the compound nucleus mass number. Our extension of that model includes an example of the pairs of A larger than his final limit aiming to make it as a general formula for any type of reactants: light, intermediate or heavy systems. A significant point is the comparison of Elastic Model calculations with the well known methods studying complete fusion and compound nucleus formation, namely with the resultants of using Proximity potential with either Sharp or Smooth cut-off approximations

  5. Motor fuel demand analysis - applied modelling in the European union

    International Nuclear Information System (INIS)

    Chorazewiez, S.

    1998-01-01

    Motor fuel demand in Europe amounts to almost half of petroleum products consumption and to thirty percent of total final energy consumption. This study considers, Firstly, the energy policies of different European countries and the ways in which the consumption of motor gasoline and automotive gas oil has developed. Secondly it provides an abstract of demand models in the energy sector, illustrating their specific characteristics. Then it proposes an economic model of automotive fuel consumption, showing motor gasoline and automotive gas oil separately over a period of thirty years (1960-1993) for five main countries in the European Union. Finally, forecasts of consumption of gasoline and diesel up to the year 2020 are given for different scenarios. (author)

  6. APPLYING PETRI NETS EXTENSIONS TO MODELING COMMERCIAL BANK ACTIVITY

    Directory of Open Access Journals (Sweden)

    Igor ENICOV

    2017-02-01

    Full Text Available The relevance of the study is determined by the need to improve the methods of modeling andsimulating commercial bank activity, including for the purpose of calculating, controlling and managingthe risk of the bank, in the context of the transition to the application of Basel III standards. Thisimprovement becomes necessary due to a direct transition to new regulatory standards when the internalassessments of the main risks become the initial data for calculating the capital adequacy of a bank. Thepurpose of this article is to argue the opportunity to formulate a theory of the commercial bank model onthe extensions of Petri nets theory. The main methods of research were the method of scientific abstractionand method of logical analysis. The main result obtained in the study and presented in the article is theargumentation of the possibility to analyze the quantitative and qualitative characteristics of acommercial bank with the help of Petri net extensions.

  7. Alexandrium minutum growth controlled by phosphorus An applied model

    OpenAIRE

    Chapelle, Annie; Labry, Claire; Sourisseau, Marc; Lebreton, Carole; Youenou, Agnes; Crassous, Marie-pierre

    2010-01-01

    Toxic algae are a worldwide problem threatening aquaculture public health and tourism Alexandrium a toxic dinoflagellate proliferates in Northwest France estuaries (i e the Penze estuary) causing Paralytic Shellfish Poisoning events Vegetative growth and in particular the role of nutrient uptake and growth rate are crucial parameters to understand toxic blooms With the goal of modelling in situ Alexandrium blooms related to environmental parameters we first try to calibrate a zero-dimensional...

  8. Applying Mechanistic Dam Breach Models to Historic Levee Breaches

    OpenAIRE

    Risher Paul; Gibson Stanford

    2016-01-01

    Hurricane Katrina elevated levee risk in the US national consciousness, motivating agencies to assess and improve their levee risk assessment methodology. Accurate computation of the flood flow magnitude and timing associated with a levee breach remains one of the most difficult and uncertain components of levee risk analysis. Contemporary methods are largely empirical and approximate, introducing substantial uncertainty to the damage and life loss models. Levee breach progressions are often ...

  9. Applying CIPP Model for Learning-Object Management

    Science.gov (United States)

    Morgado, Erla M. Morales; Peñalvo, Francisco J. García; Martín, Carlos Muñoz; Gonzalez, Miguel Ángel Conde

    Although knowledge management process needs to receive some evaluation in order to determine their suitable functionality. There is not a clear definition about the stages where LOs need to be evaluated and the specific metrics to continuously promote their quality. This paper presents a proposal for LOs evaluation during their management for e-learning systems. To achieve this, we suggest specific steps for LOs design, implementation and evaluation into the four stages proposed by CIPP model (Context, Input, Process, Product).

  10. Geometry Based Design Automation : Applied to Aircraft Modelling and Optimization

    OpenAIRE

    Amadori, Kristian

    2012-01-01

    Product development processes are continuously challenged by demands for increased efficiency. As engineering products become more and more complex, efficient tools and methods for integrated and automated design are needed throughout the development process. Multidisciplinary Design Optimization (MDO) is one promising technique that has the potential to drastically improve concurrent design. MDO frameworks combine several disciplinary models with the aim of gaining a holistic perspective of ...

  11. A theoretical intellectual capital model applied to cities

    Directory of Open Access Journals (Sweden)

    José Luis Alfaro Navarro

    2013-06-01

    Full Text Available New Management Information Systems (MIS are necessary at local level as the main source of wealth creation. Therefore, tools and approaches that provide a full future vision of any organization should be a strategic priority for economic development. In this line, cities are “centers of knowledge and sources of growth and innovation” and integrated urban development policies are necessary. These policies support communication networks and optimize location structures as strategies that provide opportunities for social and democratic participation for the citizens. This paper proposes a theoretical model to measure and evaluate the cities intellectual capital that allows determine what we must take into account to make cities a source of wealth, prosperity, welfare and future growth. Furthermore, local intellectual capital provides a long run vision. Thus, in this paper we develop and explain how to implement a model to estimate intellectual capital in cities. In this sense, our proposal is to provide a model for measuring and managing intellectual capital using socio-economic indicators for cities. These indicators offer a long term picture supported by a comprehensive strategy for those who occupy the local space, infrastructure for implementation and management of the environment for its development.

  12. Simulation of Road Traffic Applying Model-Driven Engineering

    Directory of Open Access Journals (Sweden)

    Alberto FERNÁNDEZ-ISABEL

    2016-05-01

    Full Text Available Road traffic is an important phenomenon in modern societies. The study of its different aspects in the multiple scenarios where it happens is relevant for a huge number of problems. At the same time, its scale and complexity make it hard to study. Traffic simulations can alleviate these difficulties, simplifying the scenarios to consider and controlling their variables. However, their development also presents difficulties. The main ones come from the need to integrate the way of working of researchers and developers from multiple fields. Model-Driven Engineering (MDE addresses these problems using Modelling Languages (MLs and semi-automatic transformations to organise and describe the development, from requirements to code. This paper presents a domain-specific MDE framework for simulations of road traffic. It comprises an extensible ML, support tools, and development guidelines. The ML adopts an agent-based approach, which is focused on the roles of individuals in road traffic and their decision-making. A case study shows the process to model a traffic theory with the ML, and how to specialise that specification for an existing target platform and its simulations. The results are the basis for comparison with related work.

  13. Modeling a Thermoelectric Generator Applied to Diesel Automotive Heat Recovery

    Science.gov (United States)

    Espinosa, N.; Lazard, M.; Aixala, L.; Scherrer, H.

    2010-09-01

    Thermoelectric generators (TEGs) are outstanding devices for automotive waste heat recovery. Their packaging, lack of moving parts, and direct heat to electrical conversion are the main benefits. Usually, TEGs are modeled with a constant hot-source temperature. However, energy in exhaust gases is limited, thus leading to a temperature decrease as heat is recovered. Therefore thermoelectric properties change along the TEG, affecting performance. A thermoelectric generator composed of Mg2Si/Zn4Sb3 for high temperatures followed by Bi2Te3 for low temperatures has been modeled using engineering equation solver (EES) software. The model uses the finite-difference method with a strip-fins convective heat transfer coefficient. It has been validated on a commercial module with well-known properties. The thermoelectric connection and the number of thermoelements have been addressed as well as the optimum proportion of high-temperature material for a given thermoelectric heat exchanger. TEG output power has been estimated for a typical commercial vehicle at 90°C coolant temperature.

  14. Applying a Virtual Economy Model in Mexico's Oil Sector

    International Nuclear Information System (INIS)

    Baker, G.

    1994-01-01

    The state of Mexico's oil industry, including the accomplishments of Pemex, Mexico's national oil company, was discussed, with particular reference to the progress made in the period of 1988-1994, and the outlook for innovations in the post-Salinas era. The concept of an evolutionary trend from a command economy (State as sole producer), towards market (State as regulator) or mixed economies (State as business partner) in developing countries, was introduced, placing Pemex within this evolutionary model as moving away from centralized control of oil production and distribution, while achieving international competitiveness. The concept of ''virtual market economy'' was also discussed. This model contains the legal basis of a command economy, while instituting modernization programs in order to stimulate market-economic conditions. This type of economy was considered particularly useful in this instance, sine it would allow Pemex units to operate within international performance and price benchmarks while maintaining state monopoly. Specific details of how Pemex could transform itself to a virtual market economy were outlined. It was recommended that Pemex experiment with the virtual mixed economy model; in essence, making the state a co-producer, co-transporter, and co-distributor of hydrocarbons. The effects of such a move would be to bring non-debt funding to oil and gas production, transmission, and associated industrial activities

  15. A GOMS model applied to a simplified control panel design

    International Nuclear Information System (INIS)

    Chavez, C.; Edwards, R.M.

    1992-01-01

    The design of the user interface for a new system requires many decisions to be considered. To develop sensitivity to user needs requires understanding user behavior. The how-to-do-it knowledge is a mixture of task-related and interface-related components. A conscientious analysis of these components, allows the designer to construct a model in terms of goals, operators, methods, and selection (GOMS model) rules that can be advantageously used in the design process and evaluation of a user interface. The emphasis of the present work is on describing the importance and use of a GOMS model as a formal user interface analysis tool in the development of a simplified panel for the control of a nuclear power plant. At Pennsylvania State University, a highly automated control system with a greatly simplified human interface has been proposed to improve power plant safety. Supervisory control is to be conducted with a simplified control panel with the following functions: startup, shutdown, increase power, decrease power, reset, and scram. Initial programming of the operator interface has been initiated within the framework of a U.S. Department of Energy funded university project for intelligent distributed control. A hypothesis to be tested is that this scheme can be also used to estimate mental work load content and predict human performance

  16. Applying fuzzy analytic network process in quality function deployment model

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Afsharkazemi

    2012-08-01

    Full Text Available In this paper, we propose an empirical study of QFD implementation when fuzzy numbers are used to handle the uncertainty associated with different components of the proposed model. We implement fuzzy analytical network to find the relative importance of various criteria and using fuzzy numbers we calculate the relative importance of these factors. The proposed model of this paper uses fuzzy matrix and house of quality to study the products development in QFD and also the second phase i.e. part deployment. In most researches, the primary objective is only on CRs to implement the quality function deployment and some other criteria such as production costs, manufacturing costs etc were disregarded. The results of using fuzzy analysis network process based on the QFD model in Daroupat packaging company to develop PVDC show that the most important indexes are being waterproof, resistant pill packages, and production cost. In addition, the PVDC coating is the most important index in terms of company experts’ point of view.

  17. Inverse geothermal modelling applied to Danish sedimentary basins

    DEFF Research Database (Denmark)

    Poulsen, Soren E.; Balling, Niels; Bording, Thue S.

    2017-01-01

    . The numerical model was utilized for predicting and contouring temperatures at 2000 and 3000 m depths and for two main geothermal reservoir units, the Gassum (Lower Jurassic-Upper Triassic) and Bunter/Skagerrak (Triassic) reservoirs, both currently utilized for geothermal energy production. Temperature...... gradients to depths of 2000-3000 m are generally around 25-30. degrees C km(-1), locally up to about 35. degrees C km(-1). Large regions have geothermal reservoirs with characteristic temperatures ranging from ca. 40-50. degrees C, at 1000-1500 m depth, to ca. 80-110. degrees C, at 2500-3500 m, however...

  18. Modeling external constraints: Applying expert systems to nuclear plants

    International Nuclear Information System (INIS)

    Beck, C.E.; Behera, A.K.

    1993-01-01

    Artificial Intelligence (AI) applications in nuclear plants have received much attention over the past decade. Specific applications that have been addressed include development of models and knowledge-bases, plant maintenance, operations, procedural guidance, risk assessment, and design tools. This paper examines the issue of external constraints, with a focus on the use of Al and expert systems as design tools. It also provides several suggested methods for addressing these constraints within the Al framework. These methods include a State Matrix scheme, a layered structure for the knowledge base, and application of the dynamic parameter concept

  19. Neighborhood Design, Physical Activity, and Wellbeing: Applying the Walkability Model

    Directory of Open Access Journals (Sweden)

    Adriana A. Zuniga-Teran

    2017-01-01

    Full Text Available Neighborhood design affects lifestyle physical activity, and ultimately human wellbeing. There are, however, a limited number of studies that examine neighborhood design types. In this research, we examine four types of neighborhood designs: traditional development, suburban development, enclosed community, and cluster housing development, and assess their level of walkability and their effects on physical activity and wellbeing. We examine significant associations through a questionnaire (n = 486 distributed in Tucson, Arizona using the Walkability Model. Among the tested neighborhood design types, traditional development showed significant associations and the highest value for walkability, as well as for each of the two types of walking (recreation and transportation representing physical activity. Suburban development showed significant associations and the highest mean values for mental health and wellbeing. Cluster housing showed significant associations and the highest mean value for social interactions with neighbors and for perceived safety from crime. Enclosed community did not obtain the highest means for any wellbeing benefit. The Walkability Model proved useful in identifying the walkability categories associated with physical activity and perceived crime. For example, the experience category was strongly and inversely associated with perceived crime. This study provides empirical evidence of the importance of including vegetation, particularly trees, throughout neighborhoods in order to increase physical activity and wellbeing. Likewise, the results suggest that regular maintenance is an important strategy to improve mental health and overall wellbeing in cities.

  20. Neighborhood Design, Physical Activity, and Wellbeing: Applying the Walkability Model.

    Science.gov (United States)

    Zuniga-Teran, Adriana A; Orr, Barron J; Gimblett, Randy H; Chalfoun, Nader V; Guertin, David P; Marsh, Stuart E

    2017-01-13

    Neighborhood design affects lifestyle physical activity, and ultimately human wellbeing. There are, however, a limited number of studies that examine neighborhood design types. In this research, we examine four types of neighborhood designs: traditional development, suburban development, enclosed community, and cluster housing development, and assess their level of walkability and their effects on physical activity and wellbeing. We examine significant associations through a questionnaire ( n = 486) distributed in Tucson, Arizona using the Walkability Model. Among the tested neighborhood design types, traditional development showed significant associations and the highest value for walkability, as well as for each of the two types of walking (recreation and transportation) representing physical activity. Suburban development showed significant associations and the highest mean values for mental health and wellbeing. Cluster housing showed significant associations and the highest mean value for social interactions with neighbors and for perceived safety from crime. Enclosed community did not obtain the highest means for any wellbeing benefit. The Walkability Model proved useful in identifying the walkability categories associated with physical activity and perceived crime. For example, the experience category was strongly and inversely associated with perceived crime. This study provides empirical evidence of the importance of including vegetation, particularly trees, throughout neighborhoods in order to increase physical activity and wellbeing. Likewise, the results suggest that regular maintenance is an important strategy to improve mental health and overall wellbeing in cities.

  1. Applying the Health Belief Model to college students' health behavior

    Science.gov (United States)

    Kim, Hak-Seon; Ahn, Joo

    2012-01-01

    The purpose of this research was to investigate how university students' nutrition beliefs influence their health behavioral intention. This study used an online survey engine (Qulatrics.com) to collect data from college students. Out of 253 questionnaires collected, 251 questionnaires (99.2%) were used for the statistical analysis. Confirmatory Factor Analysis (CFA) revealed that six dimensions, "Nutrition Confidence," "Susceptibility," "Severity," "Barrier," "Benefit," "Behavioral Intention to Eat Healthy Food," and "Behavioral Intention to do Physical Activity," had construct validity; Cronbach's alpha coefficient and composite reliabilities were tested for item reliability. The results validate that objective nutrition knowledge was a good predictor of college students' nutrition confidence. The results also clearly showed that two direct measures were significant predictors of behavioral intentions as hypothesized. Perceived benefit of eating healthy food and perceived barrier for eat healthy food to had significant effects on Behavioral Intentions and was a valid measurement to use to determine Behavioral Intentions. These findings can enhance the extant literature on the universal applicability of the model and serve as useful references for further investigations of the validity of the model within other health care or foodservice settings and for other health behavioral categories. PMID:23346306

  2. Evaluation of deconvolution modelling applied to numerical combustion

    Science.gov (United States)

    Mehl, Cédric; Idier, Jérôme; Fiorina, Benoît

    2018-01-01

    A possible modelling approach in the large eddy simulation (LES) of reactive flows is to deconvolve resolved scalars. Indeed, by inverting the LES filter, scalars such as mass fractions are reconstructed. This information can be used to close budget terms of filtered species balance equations, such as the filtered reaction rate. Being ill-posed in the mathematical sense, the problem is very sensitive to any numerical perturbation. The objective of the present study is to assess the ability of this kind of methodology to capture the chemical structure of premixed flames. For that purpose, three deconvolution methods are tested on a one-dimensional filtered laminar premixed flame configuration: the approximate deconvolution method based on Van Cittert iterative deconvolution, a Taylor decomposition-based method, and the regularised deconvolution method based on the minimisation of a quadratic criterion. These methods are then extended to the reconstruction of subgrid scale profiles. Two methodologies are proposed: the first one relies on subgrid scale interpolation of deconvolved profiles and the second uses parametric functions to describe small scales. Conducted tests analyse the ability of the method to capture the chemical filtered flame structure and front propagation speed. Results show that the deconvolution model should include information about small scales in order to regularise the filter inversion. a priori and a posteriori tests showed that the filtered flame propagation speed and structure cannot be captured if the filter size is too large.

  3. A unified framework for benchmark dose estimation applied to mixed models and model averaging

    DEFF Research Database (Denmark)

    Ritz, Christian; Gerhard, Daniel; Hothorn, Ludwig A.

    2013-01-01

    for hierarchical data structures, reflecting increasingly common types of assay data. We illustrate the usefulness of the methodology by means of a cytotoxicology example where the sensitivity of two types of assays are evaluated and compared. By means of a simulation study, we show that the proposed framework......This article develops a framework for benchmark dose estimation that allows intrinsically nonlinear dose-response models to be used for continuous data in much the same way as is already possible for quantal data. This means that the same dose-response model equations may be applied to both...

  4. High Y-chromosomal differentiation among ethnic groups of Dir and Swat districts, Pakistan

    DEFF Research Database (Denmark)

    Ullah, Inam; Olofsson, Jill K.; Margaryan, Ashot

    2017-01-01

    The ethnic groups that inhabit the mountainous Dir and Swat districts of northern Pakistan are marked by high levels of cultural and phenotypic diversity. To obtain knowledge of the extent of genetic diversity in this region, we investigated Y-chromosomal diversity in five population samples repr...

  5. Mathematical Modeling Applied to Prediction of Landslides in Southern Brazil

    Science.gov (United States)

    Silva, Lúcia; Araújo, João; Braga, Beatriz; Fernandes, Nelson

    2013-04-01

    Mass movements are natural phenomena that occur on the slopes and are important agents working in landscape development. These movements have caused serious damage to infrastructure and properties. In addition to the mass movements occurring in natural slopes, there is also a large number of accidents induced by human action in the landscape. The change of use and land cover for the introduction of agriculture is a good example that have affected the stability of slopes. Land use and/or land cover changes have direct and indirect effects on slope stability and frequently represent a major factor controlling the occurrence of man-induced mass movements. In Brazil, especially in the southern and southeastern regions, areas of original natural rain forest have been continuously replaced by agriculture during the last decades, leading to important modifications in soil mechanical properties and to major changes in hillslope hydrology. In these regions, such effects are amplified due to the steep hilly topography, intense summer rainfall events and dense urbanization. In November 2008, a major landslide event took place in a rural area with intensive agriculture in the state of Santa Catarina (Morro do Baú) where many catastrophic landslides were triggered after a long rainy period. In this area, the natural forest has been replaced by huge banana and pine plantations. The state of Santa Catarina in recent decades has been the scene of several incidents of mass movements such as this catastrophic event. In this study, based on field mapping and modeling, we characterize the role played by geomorphological and geological factors in controlling the spatial distribution of landslides in the Morro do Baú area. In order to attain such objective, a digital elevation model of the basin was generated with a 10m grid in which the topographic parameters were obtained. The spatial distribution of the scars from this major event was mapped from another image, obtained immediately

  6. "Let's Move" campaign: applying the extended parallel process model.

    Science.gov (United States)

    Batchelder, Alicia; Matusitz, Jonathan

    2014-01-01

    This article examines Michelle Obama's health campaign, "Let's Move," through the lens of the extended parallel process model (EPPM). "Let's Move" aims to reduce the childhood obesity epidemic in the United States. Developed by Kim Witte, EPPM rests on the premise that people's attitudes can be changed when fear is exploited as a factor of persuasion. Fear appeals work best (a) when a person feels a concern about the issue or situation, and (b) when he or she believes to have the capability of dealing with that issue or situation. Overall, the analysis found that "Let's Move" is based on past health campaigns that have been successful. An important element of the campaign is the use of fear appeals (as it is postulated by EPPM). For example, part of the campaign's strategies is to explain the severity of the diseases associated with obesity. By looking at the steps of EPPM, readers can also understand the strengths and weaknesses of "Let's Move."

  7. On combined gravity gradient components modelling for applied geophysics

    International Nuclear Information System (INIS)

    Veryaskin, Alexey; McRae, Wayne

    2008-01-01

    Gravity gradiometry research and development has intensified in recent years to the extent that technologies providing a resolution of about 1 eotvos per 1 second average shall likely soon be available for multiple critical applications such as natural resources exploration, oil reservoir monitoring and defence establishment. Much of the content of this paper was composed a decade ago, and only minor modifications were required for the conclusions to be just as applicable today. In this paper we demonstrate how gravity gradient data can be modelled, and show some examples of how gravity gradient data can be combined in order to extract valuable information. In particular, this study demonstrates the importance of two gravity gradient components, Txz and Tyz, which, when processed together, can provide more information on subsurface density contrasts than that derived solely from the vertical gravity gradient (Tzz)

  8. Applying a Hybrid MCDM Model for Six Sigma Project Selection

    Directory of Open Access Journals (Sweden)

    Fu-Kwun Wang

    2014-01-01

    Full Text Available Six Sigma is a project-driven methodology; the projects that provide the maximum financial benefits and other impacts to the organization must be prioritized. Project selection (PS is a type of multiple criteria decision making (MCDM problem. In this study, we present a hybrid MCDM model combining the decision-making trial and evaluation laboratory (DEMATEL technique, analytic network process (ANP, and the VIKOR method to evaluate and improve Six Sigma projects for reducing performance gaps in each criterion and dimension. We consider the film printing industry of Taiwan as an empirical case. The results show that our study not only can use the best project selection, but can also be used to analyze the gaps between existing performance values and aspiration levels for improving the gaps in each dimension and criterion based on the influential network relation map.

  9. Electrostatic Model Applied to ISS Charged Water Droplet Experiment

    Science.gov (United States)

    Stevenson, Daan; Schaub, Hanspeter; Pettit, Donald R.

    2015-01-01

    The electrostatic force can be used to create novel relative motion between charged bodies if it can be isolated from the stronger gravitational and dissipative forces. Recently, Coulomb orbital motion was demonstrated on the International Space Station by releasing charged water droplets in the vicinity of a charged knitting needle. In this investigation, the Multi-Sphere Method, an electrostatic model developed to study active spacecraft position control by Coulomb charging, is used to simulate the complex orbital motion of the droplets. When atmospheric drag is introduced, the simulated motion closely mimics that seen in the video footage of the experiment. The electrostatic force's inverse dependency on separation distance near the center of the needle lends itself to analytic predictions of the radial motion.

  10. Virtual building environments (VBE) - Applying information modeling to buildings

    Energy Technology Data Exchange (ETDEWEB)

    Bazjanac, Vladimir

    2004-06-21

    A Virtual Building Environment (VBE) is a ''place'' where building industry project staffs can get help in creating Building Information Models (BIM) and in the use of virtual buildings. It consists of a group of industry software that is operated by industry experts who are also experts in the use of that software. The purpose of a VBE is to facilitate expert use of appropriate software applications in conjunction with each other to efficiently support multidisciplinary work. This paper defines BIM and virtual buildings, and describes VBE objectives, set-up and characteristics of operation. It informs about the VBE Initiative and the benefits from a couple of early VBE projects.

  11. Applying the welfare model to at-own-risk discharges.

    Science.gov (United States)

    Krishna, Lalit Kumar Radha; Menon, Sumytra; Kanesvaran, Ravindran

    2017-08-01

    "At-own-risk discharges" or "self-discharges" evidences an irretrievable breakdown in the patient-clinician relationship when patients leave care facilities before completion of medical treatment and against medical advice. Dissolution of the therapeutic relationship terminates the physician's duty of care and professional liability with respect to care of the patient. Acquiescence of an at-own-risk discharge by the clinician is seen as respecting patient autonomy. The validity of such requests pivot on the assumptions that the patient is fully informed and competent to invoke an at-own-risk discharge and that care up to the point of the at-own-risk discharge meets prevailing clinical standards. Palliative care's use of a multidisciplinary team approach challenges both these assumptions. First by establishing multiple independent therapeutic relations between professionals in the multidisciplinary team and the patient who persists despite an at-own-risk discharge. These enduring therapeutic relationships negate the suggestion that no duty of care is owed the patient. Second, the continued employ of collusion, familial determinations, and the circumnavigation of direct patient involvement in family-centric societies compromises the patient's decision-making capacity and raises questions as to the patient's decision-making capacity and their ability to assume responsibility for the repercussions of invoking an at-own-risk discharge. With the validity of at-own-risk discharge request in question and the welfare and patient interest at stake, an alternative approach to assessing at-own-risk discharge requests are called for. The welfare model circumnavigates these concerns and preserves the patient's welfare through the employ of a multidisciplinary team guided holistic appraisal of the patient's specific situation that is informed by clinical and institutional standards and evidenced-based practice. The welfare model provides a robust decision-making framework for

  12. Nonspherical Radiation Driven Wind Models Applied to Be Stars

    Science.gov (United States)

    Arauxo, F. X.

    1990-11-01

    ABSTRACT. In this work we present a model for the structure of a radiatively driven wind in the meridional plane of a hot star. Rotation effects and simulation of viscous forces were included in the motion equations. The line radiation force is considered with the inclusion of the finite disk correction in self-consistent computations which also contain gravity darkening as well as distortion of the star by rotation. An application to a typical BlV star leads to mass-flux ratios between equator and pole of the order of 10 and mass loss rates in the range 5.l0 to Mo/yr. Our envelope models are flattened towards the equator and the wind terminal velocities in that region are rather high (1000 Km/s). However, in the region near the star the equatorial velocity field is dominated by rotation. RESUMEN. Se presenta un modelo de la estructura de un viento empujado radiativamente en el plano meridional de una estrella caliente. Se incluyeron en las ecuaciones de movimiento los efectos de rotaci6n y la simulaci6n de fuerzas viscosas. Se consider6 la fuerza de las lineas de radiaci6n incluyendo la correcci6n de disco finito en calculos autoconsistentes los cuales incluyen oscurecimiento gravitacional asi como distorsi6n de la estrella por rotaci6n. La aplicaci6n a una estrella tipica BlV lleva a cocientes de flujo de masa entre el ecuador y el polo del orden de 10 de perdida de masa en el intervalo 5.l0 a 10 Mo/ano. Nuestros modelos de envolvente estan achatados hacia el ecuador y las velocidads terminales del viento en esa regi6n son bastante altas (1000 Km/s). Sin embargo, en la regi6n cercana a la estrella el campo de velocidad ecuatorial esta dominado por la rotaci6n. Key words: STARS-BE -- STARS-WINDS

  13. Species Distribution Modelling of Aedes aegypti in two dengue-endemic regions of Pakistan.

    Science.gov (United States)

    Fatima, Syeda Hira; Atif, Salman; Rasheed, Syed Basit; Zaidi, Farrah; Hussain, Ejaz

    2016-03-01

    Statistical tools are effectively used to determine the distribution of mosquitoes and to make ecological inferences about the vector-borne disease dynamics. In this study, we utilised species distribution models to understand spatial patterns of Aedes aegypti in two dengue-prevalent regions of Pakistan, Lahore and Swat. Species distribution models can potentially indicate the probability of suitability of Ae. aegypti once introduced to new regions like Swat, where invasion of this species is a recent phenomenon. The distribution of Ae. aegypti was determined by applying the MaxEnt algorithm on a set of potential environmental factors and species sample records. The ecological dependency of species on each environmental variable was analysed using response curves. We quantified the statistical performance of the models based on accuracy assessment and spatial predictions. Our results suggest that Ae. aegypti is widely distributed in Lahore. Human population density and urban infrastructure are primarily responsible for greater probability of mosquito occurrence in this region. In Swat, Ae. aegypti has clumped distribution, where urban patches provide refuge to the species in an otherwise hostile heterogeneous environment and road networks are assumed to have facilitated in passive-mediated dispersal of species. In Pakistan, Ae. aegypti is expanding its range northwards; this could be associated with rapid urbanisation, trade and travel. The main implication of this expansion is that more people are at risk of dengue fever in the northern highlands of Pakistan. © 2016 John Wiley & Sons Ltd.

  14. Evaluating treatment process redesign by applying the EFQM Excellence Model.

    Science.gov (United States)

    Nabitz, Udo; Schramade, Mark; Schippers, Gerard

    2006-10-01

    To evaluate a treatment process redesign programme implementing evidence-based treatment as part of a total quality management in a Dutch addiction treatment centre. Quality management was monitored over a period of more than 10 years in an addiction treatment centre with 550 professionals. Changes are evaluated, comparing the scores on the nine criteria of the European Foundation for Quality Management (EFQM) Excellence Model before and after a major redesign of treatment processes and ISO certification. In the course of 10 years, most intake, care, and cure processes were reorganized, the support processes were restructured and ISO certified, 29 evidence-based treatment protocols were developed and implemented, and patient follow-up measuring was established to make clinical outcomes transparent. Comparing the situation before and after the changes shows that the client satisfaction scores are stable, that the evaluation by personnel and society is inconsistent, and that clinical, production, and financial outcomes are positive. The overall EFQM assessment by external assessors in 2004 shows much higher scores on the nine criteria than the assessment in 1994. Evidence-based treatment can successfully be implemented in addiction treatment centres through treatment process redesign as part of a total quality management strategy, but not all results are positive.

  15. Non local theory of excitations applied to the Hubbard model

    International Nuclear Information System (INIS)

    Kakehashi, Y; Nakamura, T; Fulde, P

    2010-01-01

    We propose a nonlocal theory of single-particle excitations. It is based on an off-diagonal effective medium and the projection operator method for treating the retarded Green function. The theory determines the nonlocal effective medium matrix elements by requiring that they are consistent with those of the self-energy of the Green function. This arrows for a description of long-range intersite correlations with high resolution in momentum space. Numerical study for the half-filled Hubbard model on the simple cubic lattice demonstrates that the theory is applicable to the strong correlation regime as well as the intermediate regime of Coulomb interaction strength. Furthermore the results show that nonlocal excitations cause sub-bands in the strong Coulomb interaction regime due to strong antiferromagnetic correlations, decrease the quasi-particle peak on the Fermi level with increasing Coulomb interaction, and shift the critical Coulomb interaction U C2 for the divergence of effective mass towards higher energies at least by a factor of two as compared with that in the single-site approximation.

  16. Applying revised gap analysis model in measuring hotel service quality.

    Science.gov (United States)

    Lee, Yu-Cheng; Wang, Yu-Che; Chien, Chih-Hung; Wu, Chia-Huei; Lu, Shu-Chiung; Tsai, Sang-Bing; Dong, Weiwei

    2016-01-01

    With the number of tourists coming to Taiwan growing by 10-20 % since 2010, the number has increased due to an increasing number of foreign tourists, particularly after deregulation allowed admitting tourist groups, followed later on by foreign individual tourists, from mainland China. The purpose of this study is to propose a revised gap model to evaluate and improve service quality in Taiwanese hotel industry. Thus, service quality could be clearly measured through gap analysis, which was more effective for offering direction in developing and improving service quality. The HOLSERV instrument was used to identify and analyze service gaps from the perceptions of internal and external customers. The sample for this study included three main categories of respondents: tourists, employees, and managers. The results show that five gaps influenced tourists' evaluations of service quality. In particular, the study revealed that Gap 1 (management perceptions vs. customer expectations) and Gap 9 (service provider perceptions of management perceptions vs. service delivery) were more critical than the others in affecting perceived service quality, making service delivery the main area of improvement. This study contributes toward an evaluation of the service quality of the Taiwanese hotel industry from the perspectives of customers, service providers, and managers, which is considerably valuable for hotel managers. It was the aim of this study to explore all of these together in order to better understand the possible gaps in the hotel industry in Taiwan.

  17. Applying Dispersive Changes to Lagrangian Particles in Groundwater Transport Models

    Science.gov (United States)

    Konikow, Leonard F.

    2010-01-01

    Method-of-characteristics groundwater transport models require that changes in concentrations computed within an Eulerian framework to account for dispersion be transferred to moving particles used to simulate advective transport. A new algorithm was developed to accomplish this transfer between nodal values and advecting particles more precisely and realistically compared to currently used methods. The new method scales the changes and adjustments of particle concentrations relative to limiting bounds of concentration values determined from the population of adjacent nodal values. The method precludes unrealistic undershoot or overshoot for concentrations of individual particles. In the new method, if dispersion causes cell concentrations to decrease during a time step, those particles in the cell having the highest concentration will decrease the most, and those with the lowest concentration will decrease the least. The converse is true if dispersion is causing concentrations to increase. Furthermore, if the initial concentration on a particle is outside the range of the adjacent nodal values, it will automatically be adjusted in the direction of the acceptable range of values. The new method is inherently mass conservative. ?? US Government 2010.

  18. Assessing the Efficacy of the SWAT Auto-Irrigation Function to Simulate Irrigation, Evapotranspiration, and Crop Response to Management Strategies of the Texas High Plains

    Directory of Open Access Journals (Sweden)

    Yong Chen

    2017-07-01

    Full Text Available In the semi-arid Texas High Plains, the underlying Ogallala Aquifer is experiencing continuing decline due to long-term pumping for irrigation with limited recharge. Accurate simulation of irrigation and other associated water balance components are critical for meaningful evaluation of the effects of irrigation management strategies. Modelers often employ auto-irrigation functions within models such as the Soil and Water Assessment Tool (SWAT. However, some studies have raised concerns as to whether the function is able to adequately simulate representative irrigation practices. In this study, observations of climate, irrigation, evapotranspiration (ET, leaf area index (LAI, and crop yield derived from an irrigated lysimeter field at the USDA-ARS Conservation and Production Research Laboratory at Bushland, Texas were used to evaluate the efficacy of the SWAT auto-irrigation functions. Results indicated good agreement between simulated and observed daily ET during both model calibration (2001–2005 and validation (2006–2010 periods for the baseline scenario (Nash-Sutcliffe efficiency; NSE ≥ 0.80. The auto-irrigation scenarios resulted in reasonable ET simulations under all the thresholds of soil water deficit (SWD triggers as indicated by NSE values > 0.5. However, the auto-irrigation function did not adequately represent field practices, due to the continuation of irrigation after crop maturity and excessive irrigation when SWD triggers were less than the static irrigation amount.

  19. Application of the Soil and Water Assessment Tool (SWAT) to predict the impact of best management practices in Jatigede Catchment Area

    Science.gov (United States)

    Ridwansyah, Iwan; Fakhrudin, M.; Wibowo, Hendro; Yulianti, Meti

    2018-02-01

    Cimanuk watershed is one of the national priority watersheds for rehabilitation considering its critical condition. In this area, Jatigede Reservoir operates, which is the second largest reservoir in Indonesia, after Jatiluhur Reservoir. The reservoir performs several functions, including flood control, irrigation for 90.000 ha of rice fields, water supply of 3.500 litres per second, and power generation of 110 MW. In 2004 the Jatigede Reservoir catchment area had a critical land area of 40.875 ha (28% of the catchment area). The sedimentation rate in Cimanuk River at Eretan station shows a high rate (5.32 mm/year), which potentially decreases the function of Jatigede Reservoir. Therefore, a strategy of Best Management Practice’s (BMP’s) is required to mitigate the problem by using SWAT hydrology modelling. The aim of this study is to examine the impact of BMP’s on surface runoff and sediment yield in Jatigede Reservoir Catchment Area. Simulations were conducted using land use in 2011. The results of this study suggest that SWAT model is considered as a reasonable modelling of BMP’s simulation concerning Nash-Sutcliffe Coefficients (0.71). The simulation is using terraces, silt pit, and dam trenches as BMP’s techniques. The BMP’s application can reduce surface runoff from 99.7 mm to 75.8 mm, and decrease sediment yield from 61.9 ton/ha/year to 40.8 ton/ha/year.

  20. Model Proposition for the Fiscal Policies Analysis Applied in Economic Field

    Directory of Open Access Journals (Sweden)

    Larisa Preda

    2007-05-01

    Full Text Available This paper presents a study about fiscal policy applied in economic development. Correlations between macroeconomics and fiscal indicators signify the first steep in our analysis. Next step is a new model proposal for the fiscal and budgetary choices. This model is applied on the date of the Romanian case.

  1. Does the interpersonal model apply across eating disorder diagnostic groups? A structural equation modeling approach.

    Science.gov (United States)

    Ivanova, Iryna V; Tasca, Giorgio A; Proulx, Geneviève; Bissada, Hany

    2015-11-01

    Interpersonal model has been validated with binge-eating disorder (BED), but it is not yet known if the model applies across a range of eating disorders (ED). The goal of this study was to investigate the validity of the interpersonal model in anorexia nervosa (restricting type; ANR and binge-eating/purge type; ANBP), bulimia nervosa (BN), BED, and eating disorder not otherwise specified (EDNOS). Data from a cross-sectional sample of 1459 treatment-seeking women diagnosed with ANR, ANBP, BN, BED and EDNOS were examined for indirect effects of interpersonal problems on ED psychopathology mediated through negative affect. Findings from structural equation modeling demonstrated the mediating role of negative affect in four of the five diagnostic groups. There were significant, medium to large (.239, .558), indirect effects in the ANR, BN, BED and EDNOS groups but not in the ANBP group. The results of the first reverse model of interpersonal problems as a mediator between negative affect and ED psychopathology were nonsignificant, suggesting the specificity of these hypothesized paths. However, in the second reverse model ED psychopathology was related to interpersonal problems indirectly through negative affect. This is the first study to find support for the interpersonal model of ED in a clinical sample of women with diverse ED diagnoses, though there may be a reciprocal relationship between ED psychopathology and relationship problems through negative affect. Negative affect partially explains the relationship between interpersonal problems and ED psychopathology in women diagnosed with ANR, BN, BED and EDNOS. Interpersonal psychotherapies for ED may be addressing the underlying interpersonal-affective difficulties, thereby reducing ED psychopathology. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Multi-Objective Validation of SWAT for Sparsely-Gauged West African River Basins—A Remote Sensing Approach

    Directory of Open Access Journals (Sweden)

    Thomas Poméon

    2018-04-01

    Full Text Available Predicting freshwater resources is a major concern in West Africa, where large parts of the population depend on rain-fed subsistence agriculture. However, a steady decline in the availability of in-situ measurements of climatic and hydrologic variables makes it difficult to simulate water resource availability with hydrological models. In this study, a modeling framework was set up for sparsely-gauged catchments in West Africa using the Soil and Water Assessment Tool (SWAT, whilst largely relying on remote sensing and reanalysis inputs. The model was calibrated using two different strategies and validated using discharge measurements. New in this study is the use of a multi-objective validation conducted to further investigate the performance of the model, where simulated actual evapotranspiration, soil moisture, and total water storage were evaluated using remote sensing data. Results show that the model performs well (R2 calibration: 0.52 and 0.51; R2 validation: 0.63 and 0.61 and the multi-objective validation reveals good agreement between predictions and observations. The study reveals the potential of using remote sensing data in sparsely-gauged catchments, resulting in good performance and providing data for evaluating water balance components that are not usually validated. The modeling framework presented in this study is the basis for future studies, which will address model response to extreme drought and flood events and further examine the coincidence with Gravity Recovery and Climate Experiment (GRACE total water storage retrievals.

  3. Applying Catastrophe Theory to an Information-Processing Model of Problem Solving in Science Education

    Science.gov (United States)

    Stamovlasis, Dimitrios; Tsaparlis, Georgios

    2012-01-01

    In this study, we test an information-processing model (IPM) of problem solving in science education, namely the working memory overload model, by applying catastrophe theory. Changes in students' achievement were modeled as discontinuities within a cusp catastrophe model, where working memory capacity was implemented as asymmetry and the degree…

  4. Calibration of a Distributed Hydrological Model using Remote Sensing Evapotranspiration data in the Semi-Arid Punjab Region of Pakista

    Science.gov (United States)

    Becker, R.; Usman, M.

    2017-12-01

    A SWAT (Soil Water Assessment Tool) model is applied in the semi-arid Punjab region in Pakistan. The physically based hydrological model is set up to simulate hydrological processes and water resources demands under future land use, climate change and irrigation management scenarios. In order to successfully run the model, detailed focus is laid on the calibration procedure of the model. The study deals with the following calibration issues:i. lack of reliable calibration/validation data, ii. difficulty to accurately model a highly managed system with a physically based hydrological model and iii. use of alternative and spatially distributed data sets for model calibration. In our study area field observations are rare and the entirely human controlled irrigation system renders central calibration parameters (e.g. runoff/curve number) unsuitable, as it can't be assumed that they represent the natural behavior of the hydrological system. From evapotranspiration (ET) however principal hydrological processes can still be inferred. Usman et al. (2015) derived satellite based monthly ET data for our study area based on SEBAL (Surface Energy Balance Algorithm) and created a reliable ET data set which we use in this study to calibrate our SWAT model. The initial SWAT model performance is evaluated with respect to the SEBAL results using correlation coefficients, RMSE, Nash-Sutcliffe efficiencies and mean differences. Particular focus is laid on the spatial patters, investigating the potential of a spatially differentiated parameterization instead of just using spatially uniform calibration data. A sensitivity analysis reveals the most sensitive parameters with respect to changes in ET, which are then selected for the calibration process.Using the SEBAL-ET product we calibrate the SWAT model for the time period 2005-2006 using a dynamically dimensioned global search algorithm to minimize RMSE. The model improvement after the calibration procedure is finally evaluated based

  5. Methodology for Applying Cyber Security Risk Evaluation from BN Model to PSA Model

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Jin Soo; Heo, Gyun Young [Kyung Hee University, Youngin (Korea, Republic of); Kang, Hyun Gook [KAIST, Dajeon (Korea, Republic of); Son, Han Seong [Joongbu University, Chubu (Korea, Republic of)

    2014-08-15

    There are several advantages to use digital equipment such as cost, convenience, and availability. It is inevitable to use the digital I and C equipment replaced analog. Nuclear facilities have already started applying the digital system to I and C system. However, the nuclear facilities also have to change I and C system even though it is difficult to use digital equipment due to high level of safety, irradiation embrittlement, and cyber security. A cyber security which is one of important concerns to use digital equipment can affect the whole integrity of nuclear facilities. For instance, cyber-attack occurred to nuclear facilities such as the SQL slammer worm, stuxnet, DUQU, and flame. The regulatory authorities have published many regulatory requirement documents such as U.S. NRC Regulatory Guide 5.71, 1.152, IAEA guide NSS-17, IEEE Standard, and KINS Regulatory Guide. One of the important problem of cyber security research for nuclear facilities is difficulty to obtain the data through the penetration experiments. Therefore, we make cyber security risk evaluation model with Bayesian network (BN) for nuclear reactor protection system (RPS), which is one of the safety-critical systems to trip the reactor when the accident is happened to the facilities. BN can be used for overcoming these problems. We propose a method to apply BN cyber security model to probabilistic safety assessment (PSA) model, which had been used for safety assessment of system, structure and components of facility. The proposed method will be able to provide the insight of safety as well as cyber risk to the facility.

  6. Methodology for Applying Cyber Security Risk Evaluation from BN Model to PSA Model

    International Nuclear Information System (INIS)

    Shin, Jin Soo; Heo, Gyun Young; Kang, Hyun Gook; Son, Han Seong

    2014-01-01

    There are several advantages to use digital equipment such as cost, convenience, and availability. It is inevitable to use the digital I and C equipment replaced analog. Nuclear facilities have already started applying the digital system to I and C system. However, the nuclear facilities also have to change I and C system even though it is difficult to use digital equipment due to high level of safety, irradiation embrittlement, and cyber security. A cyber security which is one of important concerns to use digital equipment can affect the whole integrity of nuclear facilities. For instance, cyber-attack occurred to nuclear facilities such as the SQL slammer worm, stuxnet, DUQU, and flame. The regulatory authorities have published many regulatory requirement documents such as U.S. NRC Regulatory Guide 5.71, 1.152, IAEA guide NSS-17, IEEE Standard, and KINS Regulatory Guide. One of the important problem of cyber security research for nuclear facilities is difficulty to obtain the data through the penetration experiments. Therefore, we make cyber security risk evaluation model with Bayesian network (BN) for nuclear reactor protection system (RPS), which is one of the safety-critical systems to trip the reactor when the accident is happened to the facilities. BN can be used for overcoming these problems. We propose a method to apply BN cyber security model to probabilistic safety assessment (PSA) model, which had been used for safety assessment of system, structure and components of facility. The proposed method will be able to provide the insight of safety as well as cyber risk to the facility

  7. Practical Findings from Applying the PSD Model for Evaluating Software Design Specifications

    Science.gov (United States)

    Räisänen, Teppo; Lehto, Tuomas; Oinas-Kukkonen, Harri

    This paper presents practical findings from applying the PSD model to evaluating the support for persuasive features in software design specifications for a mobile Internet device. On the one hand, our experiences suggest that the PSD model fits relatively well for evaluating design specifications. On the other hand, the model would benefit from more specific heuristics for evaluating each technique to avoid unnecessary subjectivity. Better distinction between the design principles in the social support category would also make the model easier to use. Practitioners who have no theoretical background can apply the PSD model to increase the persuasiveness of the systems they design. The greatest benefit of the PSD model for researchers designing new systems may be achieved when it is applied together with a sound theory, such as the Elaboration Likelihood Model. Using the ELM together with the PSD model, one may increase the chances for attitude change.

  8. A comparison of economic evaluation models as applied to geothermal energy technology

    Science.gov (United States)

    Ziman, G. M.; Rosenberg, L. S.

    1983-01-01

    Several cost estimation and financial cash flow models have been applied to a series of geothermal case studies. In order to draw conclusions about relative performance and applicability of these models to geothermal projects, the consistency of results was assessed. The model outputs of principal interest in this study were net present value, internal rate of return, or levelized breakeven price. The models used were VENVAL, a venture analysis model; the Geothermal Probabilistic Cost Model (GPC Model); the Alternative Power Systems Economic Analysis Model (APSEAM); the Geothermal Loan Guarantee Cash Flow Model (GCFM); and the GEOCOST and GEOCITY geothermal models. The case studies to which the models were applied include a geothermal reservoir at Heber, CA; a geothermal eletric power plant to be located at the Heber site; an alcohol fuels production facility to be built at Raft River, ID; and a direct-use, district heating system in Susanville, CA.

  9. Semantic Web applications and tools for the life sciences: SWAT4LS 2010.

    Science.gov (United States)

    Burger, Albert; Paschke, Adrian; Romano, Paolo; Marshall, M Scott; Splendiani, Andrea

    2012-01-25

    As Semantic Web technologies mature and new releases of key elements, such as SPARQL 1.1 and OWL 2.0, become available, the Life Sciences continue to push the boundaries of these technologies with ever more sophisticated tools and applications. Unsurprisingly, therefore, interest in the SWAT4LS (Semantic Web Applications and Tools for the Life Sciences) activities have remained high, as was evident during the third international SWAT4LS workshop held in Berlin in December 2010. Contributors to this workshop were invited to submit extended versions of their papers, the best of which are now made available in the special supplement of BMC Bioinformatics. The papers reflect the wide range of work in this area, covering the storage and querying of Life Sciences data in RDF triple stores, tools for the development of biomedical ontologies and the semantics-based integration of Life Sciences as well as clinicial data.

  10. Scaling and design report of ECC performance test facility (SWAT) of SMART

    International Nuclear Information System (INIS)

    Cho, Seok; Ko, Yong Ju; Cho, Young Il; Kim, Jeong Tak; Choi, Nam Hyun; Shin Yong Chul; Park, Choon Kyong; Kwon, Tae Soon; Lee, Sung Jae

    2010-12-01

    SWAT (SMART ECC Water Asymmetric Two-phase choking test facility) was designed by 1/5 scaling ratio using the modified linear scaling method. The design characteristics of the SMART such that the elevation of RCP suction nozzles is the same with that of the ECC injection nozzles are maintained to reduce a distortion caused by the gravitational effect. Thermal hydraulic phenomena in a test facility designed by the modified linear scaling method can be simulated more accurately than those by the full-height and reduced area scaling method. The main part of the test section is SG-side upper down-comer. The boundary conditions are saturated steam and water flow condition and drain flow rate to control the collapsed water level in the down-comer. The test data of the SWAT can produce the well-defined boundary condition to validate the thermal hydraulic analysis code for the SMART

  11. Scaling and design report of ECC performance test facility (SWAT) of SMART

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Seok; Ko, Yong Ju; Cho, Young Il; Kim, Jeong Tak; Choi, Nam Hyun; Shin Yong Chul; Park, Choon Kyong; Kwon, Tae Soon; Lee, Sung Jae [KAERI, Daejeon (Korea, Republic of)

    2010-12-15

    SWAT (SMART ECC Water Asymmetric Two-phase choking test facility) was designed by 1/5 scaling ratio using the modified linear scaling method. The design characteristics of the SMART such that the elevation of RCP suction nozzles is the same with that of the ECC injection nozzles are maintained to reduce a distortion caused by the gravitational effect. Thermal hydraulic phenomena in a test facility designed by the modified linear scaling method can be simulated more accurately than those by the full-height and reduced area scaling method. The main part of the test section is SG-side upper down-comer. The boundary conditions are saturated steam and water flow condition and drain flow rate to control the collapsed water level in the down-comer. The test data of the SWAT can produce the well-defined boundary condition to validate the thermal hydraulic analysis code for the SMART

  12. Sensitivity analysis for hydrology and pesticide supply towards the river in SWAT

    Science.gov (United States)

    Holvoet, K.; van Griensven, A.; Seuntjens, P.; Vanrolleghem, P. A.

    The dynamic behaviour of pesticides in river systems strongly depends on varying climatological conditions and agricultural management practices. To describe this behaviour at the river-basin scale, integrated hydrological and water quality models are needed. A crucial step in understanding the various processes determining pesticide fate is to perform a sensitivity analysis. Sensitivity analysis for hydrology and pesticide supply in SWAT (Soil and Water Assessment Tool) will provide useful support for the development of a reliable hydrological model and will give insight in which parameters are most sensitive concerning pesticide supply towards rivers. The study was performed on the Nil catchment in Belgium. In this study we utilised an LH-OAT sensitivity analysis. The LH-OAT method combines the One-factor-At-a-Time (OAT) design and Latin Hypercube (LH) sampling by taking the Latin Hypercube samples as initial points for an OAT design. By means of the LH-OAT sensitivity analysis, the dominant hydrological parameters were determined and a reduction of the number of model parameters was performed. Dominant hydrological parameters were the curve number (CN2), the surface runoff lag (surlag), the recharge to deep aquifer (rchrg_dp) and the threshold depth of water in the shallow aquifer (GWQMN). Next, the selected parameters were estimated by manual calibration. Hereby, the Nash-Sutcliffe coefficient of efficiency improved from an initial value of -22.4 to +0.53. In the second part, sensitivity analyses were performed to provide insight in which parameters or model inputs contribute most to variance in pesticide output. The results of this study show that for the Nil catchment, hydrologic parameters are dominant in controlling pesticide predictions. The other parameter that affects pesticide concentrations in surface water is ‘apfp_pest’, which meaning was changed into a parameter that controls direct losses to the river system (e.g., through the clean up of spray

  13. SWAT-MODSIM-PSO optimization of multi-crop planning in the Karkheh River Basin, Iran, under the impacts of climate change.

    Science.gov (United States)

    Fereidoon, Majid; Koch, Manfred

    2018-07-15

    Agriculture is one of the environmental/economic sectors that may adversely be affected by climate change, especially, in already nowadays water-scarce regions, like the Middle East. One way to cope with future changes in absolute as well as seasonal (irrigation) water amounts can be the adaptation of the agricultural crop pattern in a region, i.e. by planting crops which still provide high yields and so economic benefits to farmers under such varying climate conditions. To do this properly, the whole cascade starting from climate change, effects on hydrology and surface water availability, subsequent effects on crop yield, agricultural areas available, and, finally, economic value of a multi-crop cultivation pattern must be known. To that avail, a complex coupled simulation-optimization tool SWAT-LINGO-MODSIM-PSO (SLMP) has been developed here and used to find the future optimum cultivation area of crops for the maximization of the economic benefits in five irrigation-fed agricultural plains in the south of the Karkheh River Basin (KRB) southwest Iran. Starting with the SWAT distributed hydrological model, the KR-streamflow as well as the inflow into the Karkheh-reservoir, as the major storage of irrigation water, is calibrated and validated, based on 1985-2004 observed discharge data. In the subsequent step, the SWAT-predicted streamflow is fed into the MODSIM river basin Decision Support System to simulate and optimize the water allocation between different water users (agricultural, environmental, municipal and industrial) under standard operating policy (SOP) rules. The final step is the maximization of the economic benefit in the five agricultural plains through constrained PSO (particle swarm optimization) by adjusting the cultivation areas (decision variables) of different crops (wheat, barley, maize and "others"), taking into account their specific prizes and optimal crop yields under water deficiency, with the latter computed in the LINGO

  14. Experiences on removal of sodium-water reaction products in SWAT-3

    International Nuclear Information System (INIS)

    Tanabe, H.; Hiroi, H.; Sato, M.; Otaka, J.

    2002-01-01

    This report summarizes experiences and information concerning the removal of sodium water reaction products (SMRP) obtained through large leak tests of the Steam Generator Safety Test Facility (SWAT-3) at PNC/OEC, which were conducted to validate the safety design of steam generators of a prototype LMFBR Monju. The following three problems are discussed here: (1) drainability of SWRP, (2) removal of SWRP by using a cold trap, and (3) steam cleaning of SWRP. (author)

  15. Modeling segregated in- situ combustion processes through a vertical displacement model applied to a Colombian field

    International Nuclear Information System (INIS)

    Guerra Aristizabal, Jose Julian; Grosso Vargas, Jorge Luis

    2005-01-01

    Recently it has been proposed the incorporation of horizontal well technologies in thermal EOR processes like the in situ combustion process (ISC). This has taken to the conception of new recovery mechanisms named here as segregated in-situ combustion processes, which are conventional in-situ combustion process with a segregated flow component. Top/Down combustion, Combustion Override Split-production Horizontal-well and Toe-to-Heel Air Injection are three of these processes, which incorporate horizontal producers and gravity drainage phenomena. When applied to thick reservoirs a process of this nature could be reasonably modeled under concepts of conventional in-situ combustion and Crestal Gas injection, especially for heavy oils mobile at reservoir conditions. A process of this nature has been studied through an analytic model conceived for the particular conditions of the Castilla field, a homogeneous thick anticline structure containing high mobility heavy oil, which seems to be an excellent candidate for the application of these technologies

  16. Possibilities and limitations of applying software reliability growth models to safety-critical software

    International Nuclear Information System (INIS)

    Kim, Man Cheol; Jang, Seung Cheol; Ha, Jae Joo

    2007-01-01

    It is generally known that software reliability growth models such as the Jelinski-Moranda model and the Goel-Okumoto's Non-Homogeneous Poisson Process (NHPP) model cannot be applied to safety-critical software due to a lack of software failure data. In this paper, by applying two of the most widely known software reliability growth models to sample software failure data, we demonstrate the possibility of using the software reliability growth models to prove the high reliability of safety-critical software. The high sensitivity of a piece of software's reliability to software failure data, as well as a lack of sufficient software failure data, is also identified as a possible limitation when applying the software reliability growth models to safety-critical software

  17. Applying different quality and safety models in healthcare improvement work: Boundary objects and system thinking

    International Nuclear Information System (INIS)

    Wiig, Siri; Robert, Glenn; Anderson, Janet E.; Pietikainen, Elina; Reiman, Teemu; Macchi, Luigi; Aase, Karina

    2014-01-01

    A number of theoretical models can be applied to help guide quality improvement and patient safety interventions in hospitals. However there are often significant differences between such models and, therefore, their potential contribution when applied in diverse contexts. The aim of this paper is to explore how two such models have been applied by hospitals to improve quality and safety. We describe and compare the models: (1) The Organizing for Quality (OQ) model, and (2) the Design for Integrated Safety Culture (DISC) model. We analyze the theoretical foundations of the models, and show, by using a retrospective comparative case study approach from two European hospitals, how these models have been applied to improve quality and safety. The analysis shows that differences appear in the theoretical foundations, practical approaches and applications of the models. Nevertheless, the case studies indicate that the choice between the OQ and DISC models is of less importance for guiding the practice of quality and safety improvement work, as they are both systemic and share some important characteristics. The main contribution of the models lay in their role as boundary objects directing attention towards organizational and systems thinking, culture, and collaboration

  18. Assessment of future climate change impacts on nonpoint source pollution in snowmelt period for a cold area using SWAT.

    Science.gov (United States)

    Wang, Yu; Bian, Jianmin; Zhao, Yongsheng; Tang, Jie; Jia, Zhuo

    2018-02-05

    The source area of Liao River is a typical cold region in northeastern China, which experiences serious problems with agricultural nonpoint source pollution (NPS), it is important to understand future climate change impacts on NPS in the watershed. This issue has been investigated by coupling semi distributed hydrological model (SWAT), statistical downscaling model (SDSM) and global circulation model (GCMs). The results show that annual average temperature would rise by 2.1 °C (1.3 °C) in the 2080 s under scenario RCP8.5 (RCP4.5), and annual precipitation would increase by 67 mm (33 mm). The change in winter temperature and precipitation is most significant with an increase by 0.23 °C/10a (0.17 °C/10a) and 1.94 mm/10a (2.78 mm/10a). The future streamflow, TN and TP loads would decrease by 19.05% (10.59%), 12.27% (8.81%) and 10.63% (6.11%), respectively. Monthly average streamflow, TN and TP loads would decrease from March to November, and increase from December to February. This is because the increased precipitation and temperature in winter, which made the spring snowpack melting earlier. These study indicate the trends of nonpoint source pollution during the snowmelt period under climate change conditions, accordingly adaptation measures will be necessary.

  19. Temporal-spatial distribution of non-point source pollution in a drinking water source reservoir watershed based on SWAT

    Directory of Open Access Journals (Sweden)

    M. Wang

    2015-05-01

    Full Text Available The conservation of drinking water source reservoirs has a close relationship between regional economic development and people’s livelihood. Research on the non-point pollution characteristics in its watershed is crucial for reservoir security. Tang Pu Reservoir watershed was selected as the study area. The non-point pollution model of Tang Pu Reservoir was established based on the SWAT (Soil and Water Assessment Tool model. The model was adjusted to analyse the temporal-spatial distribution patterns of total nitrogen (TN and total phosphorus (TP. The results showed that the loss of TN and TP in the reservoir watershed were related to precipitation in flood season. And the annual changes showed an "M" shape. It was found that the contribution of loss of TN and TP accounted for 84.5% and 85.3% in high flow years, and for 70.3% and 69.7% in low flow years, respectively. The contributions in normal flow years were 62.9% and 63.3%, respectively. The TN and TP mainly arise from Wangtan town, Gulai town, and Wangyuan town, etc. In addition, it was found that the source of TN and TP showed consistency in space.

  20. A Research on the E-commerce Applied to the Construction of Marketing Model

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The function of E-commerce is becoming more and more widely applied to many fields,which bring about some new challenges and opportunities for the construction of marketing model.It is proved that the more E-com- merce applied to the construction of marketing,the more precision of forecast for the enterprises can acquire,which is very helpful for the production and marketing of enterprises.Therefore,the research on the E-commerce applied to the construction of marketing is popular today.This paper applie...

  1. Unified Modeling of Discrete Event and Control Systems Applied in Manufacturing

    Directory of Open Access Journals (Sweden)

    Amanda Arêas de Souza

    2015-05-01

    Full Text Available For the development of both a simulation modeland a control system, it is necessary to build, inadvance, a conceptual model. This is what isusually suggested by the methodologies applied inprojects of this nature. Some conceptual modelingtechniques allow for a better understanding ofthe simulation model, and a clear descriptionof the logic of control systems. Therefore, thispaper aims to present and evaluate conceptuallanguages for unified modeling of models ofdiscrete event simulation and control systemsapplied in manufacturing. The results show thatthe IDEF-SIM language can be applied both insimulation systems and in process control.

  2. Incorporation of the equilibrium temperature approach in a Soil and Water Assessment Tool hydroclimatological stream temperature model

    Science.gov (United States)

    Du, Xinzhong; Shrestha, Narayan Kumar; Ficklin, Darren L.; Wang, Junye

    2018-04-01

    Stream temperature is an important indicator for biodiversity and sustainability in aquatic ecosystems. The stream temperature model currently in the Soil and Water Assessment Tool (SWAT) only considers the impact of air temperature on stream temperature, while the hydroclimatological stream temperature model developed within the SWAT model considers hydrology and the impact of air temperature in simulating the water-air heat transfer process. In this study, we modified the hydroclimatological model by including the equilibrium temperature approach to model heat transfer processes at the water-air interface, which reflects the influences of air temperature, solar radiation, wind speed and streamflow conditions on the heat transfer process. The thermal capacity of the streamflow is modeled by the variation of the stream water depth. An advantage of this equilibrium temperature model is the simple parameterization, with only two parameters added to model the heat transfer processes. The equilibrium temperature model proposed in this study is applied and tested in the Athabasca River basin (ARB) in Alberta, Canada. The model is calibrated and validated at five stations throughout different parts of the ARB, where close to monthly samplings of stream temperatures are available. The results indicate that the equilibrium temperature model proposed in this study provided better and more consistent performances for the different regions of the ARB with the values of the Nash-Sutcliffe Efficiency coefficient (NSE) greater than those of the original SWAT model and the hydroclimatological model. To test the model performance for different hydrological and environmental conditions, the equilibrium temperature model was also applied to the North Fork Tolt River Watershed in Washington, United States. The results indicate a reasonable simulation of stream temperature using the model proposed in this study, with minimum relative error values compared to the other two models

  3. Applying the ISO 9126 Model to the Evaluation of an E-learning System in Iran

    OpenAIRE

    Hossein Pedram; Davood Karimzadegan Moghaddam; Zhaleh Asheghi

    2012-01-01

    One of the models presented in e-learning quality system field is ISO 9126 model, which applied in this research to evaluate e-learning system of Amirkabir University. This model system for evaluation, the six main variables provided that each of these variables by several other indicators was measured. Thus, the model parameters as ISO 9126 and turned the questionnaire survey among samples (120 experts and students of Amirkabir University) and the distribution were completed. Based on the re...

  4. Applying MDA to SDR for Space to Model Real-time Issues

    Science.gov (United States)

    Blaser, Tammy M.

    2007-01-01

    NASA space communications systems have the challenge of designing SDRs with highly-constrained Size, Weight and Power (SWaP) resources. A study is being conducted to assess the effectiveness of applying the MDA Platform-Independent Model (PIM) and one or more Platform-Specific Models (PSM) specifically to address NASA space domain real-time issues. This paper will summarize our experiences with applying MDA to SDR for Space to model real-time issues. Real-time issues to be examined, measured, and analyzed are: meeting waveform timing requirements and efficiently applying Real-time Operating System (RTOS) scheduling algorithms, applying safety control measures, and SWaP verification. Real-time waveform algorithms benchmarked with the worst case environment conditions under the heaviest workload will drive the SDR for Space real-time PSM design.

  5. Future integrated aquifer vulnerability assessment considering land use / land cover and climate change using DRASTIC and SWAT

    Science.gov (United States)

    Jang, W.; Engel, B.; Chaubey, I.

    2015-12-01

    Climate change causes significant changes to temperature regimes and precipitation patterns across the world. Such alterations in climate pose serious risks for not only inland freshwater ecosystems but also groundwater systems, and may adversely affect numerous critical services they provide to humans. All groundwater results from precipitation, and precipitation is affected by climate change. Climate change is also influenced by land use / land cover (LULC) change and vice versa. According to Intergovernmental Panel on Climate Change (IPCC) reports, climate change is caused by global warming which is generated by the increase of greenhouse gas (GHG) emissions in the atmosphere. LULC change is a major driving factor causing an increase in GHG emissions. LULC change data (years 2006-2100) will be produced by the Land Transformation Model (LTM) which simulates spatial patterns of LULC change over time. MIROC5 (years 2006-2100) will be obtained considering GCMs and ensemble characteristics such as resolution and trend of temperature and precipitation which is a consistency check with observed data from local weather stations and historical data from GCMs output data. Thus, MIROC5 will be used to account for future climate change scenarios and relationship between future climate change and alteration of groundwater quality in this study. For efficient groundwater resources management, integrated aquifer vulnerability assessments (= intrinsic vulnerability + hazard potential assessment) are required. DRASTIC will be used to evaluate intrinsic vulnerability, and aquifer hazard potential will be evaluated by Soil and Water Assessment Tool (SWAT) which can simulate pollution potential from surface and transport properties of contaminants. Thus, for effective integrated aquifer vulnerability assessment for LULC and climate change in the Midwestern United States, future projected LULC and climate data from the LTM and GCMs will be incorporated with DRASTIC and SWAT. It is

  6. To Be or Not to Be an Entrepreneur: Applying a Normative Model to Career Decisions

    Science.gov (United States)

    Callanan, Gerard A.; Zimmerman, Monica

    2016-01-01

    Reflecting the need for a better and broader understanding of the factors influencing the choices to enter into or exit an entrepreneurial career, this article applies a structured, normative model of career management to the career decision-making of entrepreneurs. The application of a structured model can assist career counselors, college career…

  7. How High Is the Tramping Track? Mathematising and Applying in a Calculus Model-Eliciting Activity

    Science.gov (United States)

    Yoon, Caroline; Dreyfus, Tommy; Thomas, Michael O. J.

    2010-01-01

    Two complementary processes involved in mathematical modelling are mathematising a realistic situation and applying a mathematical technique to a given realistic situation. We present and analyse work from two undergraduate students and two secondary school teachers who engaged in both processes during a mathematical modelling task that required…

  8. Divorce and Child Behavior Problems: Applying Latent Change Score Models to Life Event Data

    Science.gov (United States)

    Malone, Patrick S.; Lansford, Jennifer E.; Castellino, Domini R.; Berlin, Lisa J.; Dodge, Kenneth A.; Bates, John E.; Pettit, Gregory S.

    2004-01-01

    Effects of parents' divorce on children's adjustment have been studied extensively. This article applies new advances in trajectory modeling to the problem of disentangling the effects of divorce on children's adjustment from related factors such as the child's age at the time of divorce and the child's gender. Latent change score models were used…

  9. Applying circular economy innovation theory in business process modeling and analysis

    Science.gov (United States)

    Popa, V.; Popa, L.

    2017-08-01

    The overall aim of this paper is to develop a new conceptual framework for business process modeling and analysis using circular economy innovative theory as a source for business knowledge management. The last part of the paper presents an author’s proposed basic structure for a new business models applying circular economy innovation theories. For people working on new innovative business models in the field of the circular economy this paper provides new ideas for clustering their concepts.

  10. Applying a Particle-only Model to the HL Tau Disk

    OpenAIRE

    Tabeshian, Maryam; Wiegert, Paul A.

    2018-01-01

    Observations have revealed rich structures in protoplanetary disks, offering clues about their embedded planets. Due to the complexities introduced by the abundance of gas in these disks, modeling their structure in detail is computationally intensive, requiring complex hydrodynamic codes and substantial computing power. It would be advantageous if computationally simpler models could provide some preliminary information on these disks. Here we apply a particle-only model (that we developed f...

  11. Modeling of power train by applying the virtual prototype concept; Kaso genkei ni yoru power train no model ka

    Energy Technology Data Exchange (ETDEWEB)

    Hiramatsu, S; Harada, Y; Arakawa, H; Komori, S [Mazda Motor Corp., Hiroshima (Japan); Sumida, S [U-Shin Corp., Tokyo (Japan)

    1997-10-01

    This paper describes the simulation of power train that includes the model developed by applying the virtual prototype concept. By this concept, subsystem models which consist of functional model and mechanism models are integrated into a total system model. This peculiarity in architecture of model, which is called the hierarchical structure, enables us to model a system of large scale with many units, systems and parts easily. Two kinds of computer simulations are performed. One is engine revolution fluctuation by accessory load input, and the other is changing gears by automatic transmission. They are verified to have sufficient accuracy. 2 refs., 12 figs.

  12. Recent progress and modern challenges in applied mathematics, modeling and computational science

    CERN Document Server

    Makarov, Roman; Belair, Jacques

    2017-01-01

    This volume is an excellent resource for professionals in various areas of applications of mathematics, modeling, and computational science. It focuses on recent progress and modern challenges in these areas. The volume provides a balance between fundamental theoretical and applied developments, emphasizing the interdisciplinary nature of modern trends and detailing state-of-the-art achievements in Applied Mathematics, Modeling, and Computational Science.  The chapters have been authored by international experts in their respective fields, making this book ideal for researchers in academia, practitioners, and graduate students. It can also serve as a reference in the diverse selected areas of applied mathematics, modelling, and computational sciences, and is ideal for interdisciplinary collaborations.

  13. Experiment and modeling of an atmospheric pressure arc in an applied oscillating magnetic field

    International Nuclear Information System (INIS)

    Karasik, Max; Roquemore, A. L.; Zweben, S. J.

    2000-01-01

    A set of experiments are carried out to measure and understand the response of a free-burning atmospheric pressure carbon arc to applied transverse dc and ac magnetic fields. The arc is found to deflect parabolically for the dc field and assumes a growing sinusoidal structure for the ac field. A simple analytic two-parameter fluid model of the arc dynamics is derived, in which the arc response is governed by the arc jet originating at the cathode, with the applied JxB force balanced by inertia. Time variation of the applied field allows evaluation of the parameters individually. A fit of the model to the experimental data gives a value for the average jet speed an order of magnitude below Maecker's estimate of the maximum jet speed [H. Maecker, Z. Phys. 141, 198 (1955)]. An example industrial application of the model is considered. (c) 2000 American Institute of Physics

  14. Making Faces - State-Space Models Applied to Multi-Modal Signal Processing

    DEFF Research Database (Denmark)

    Lehn-Schiøler, Tue

    2005-01-01

    The two main focus areas of this thesis are State-Space Models and multi modal signal processing. The general State-Space Model is investigated and an addition to the class of sequential sampling methods is proposed. This new algorithm is denoted as the Parzen Particle Filter. Furthermore...... optimizer can be applied to speed up convergence. The linear version of the State-Space Model, the Kalman Filter, is applied to multi modal signal processing. It is demonstrated how a State-Space Model can be used to map from speech to lip movements. Besides the State-Space Model and the multi modal...... application an information theoretic vector quantizer is also proposed. Based on interactions between particles, it is shown how a quantizing scheme based on an analytic cost function can be derived....

  15. Guidelines for Applying Cohesive Models to the Damage Behaviour of Engineering Materials and Structures

    CERN Document Server

    Schwalbe, Karl-Heinz; Cornec, Alfred

    2013-01-01

    This brief provides guidance for the application of cohesive models to determine damage and fracture in materials and structural components. This can be done for configurations with or without a pre-existing crack. Although the brief addresses structural behaviour, the methods described herein may also be applied to any deformation induced material damage and failure, e.g. those occurring during manufacturing processes. The methods described are applicable to the behaviour of ductile metallic materials and structural components made thereof. Hints are also given for applying the cohesive model to other materials.

  16. OpenMP parallelization of a gridded SWAT (SWATG)

    Science.gov (United States)

    Zhang, Ying; Hou, Jinliang; Cao, Yongpan; Gu, Juan; Huang, Chunlin

    2017-12-01

    Large-scale, long-term and high spatial resolution simulation is a common issue in environmental modeling. A Gridded Hydrologic Response Unit (HRU)-based Soil and Water Assessment Tool (SWATG) that integrates grid modeling scheme with different spatial representations also presents such problems. The time-consuming problem affects applications of very high resolution large-scale watershed modeling. The OpenMP (Open Multi-Processing) parallel application interface is integrated with SWATG (called SWATGP) to accelerate grid modeling based on the HRU level. Such parallel implementation takes better advantage of the computational power of a shared memory computer system. We conducted two experiments at multiple temporal and spatial scales of hydrological modeling using SWATG and SWATGP on a high-end server. At 500-m resolution, SWATGP was found to be up to nine times faster than SWATG in modeling over a roughly 2000 km2 watershed with 1 CPU and a 15 thread configuration. The study results demonstrate that parallel models save considerable time relative to traditional sequential simulation runs. Parallel computations of environmental models are beneficial for model applications, especially at large spatial and temporal scales and at high resolutions. The proposed SWATGP model is thus a promising tool for large-scale and high-resolution water resources research and management in addition to offering data fusion and model coupling ability.

  17. Applying the Business Process and Practice Alignment Meta-model: Daily Practices and Process Modelling

    Directory of Open Access Journals (Sweden)

    Ventura Martins Paula

    2017-03-01

    Full Text Available Background: Business Process Modelling (BPM is one of the most important phases of information system design. Business Process (BP meta-models allow capturing informational and behavioural aspects of business processes. Unfortunately, standard BP meta-modelling approaches focus just on process description, providing different BP models. It is not possible to compare and identify related daily practices in order to improve BP models. This lack of information implies that further research in BP meta-models is needed to reflect the evolution/change in BP. Considering this limitation, this paper introduces a new BP meta-model designed by Business Process and Practice Alignment Meta-model (BPPAMeta-model. Our intention is to present a meta-model that addresses features related to the alignment between daily work practices and BP descriptions. Objectives: This paper intends to present a metamodel which is going to integrate daily work information into coherent and sound process definitions. Methods/Approach: The methodology employed in the research follows a design-science approach. Results: The results of the case study are related to the application of the proposed meta-model to align the specification of a BP model with work practices models. Conclusions: This meta-model can be used within the BPPAM methodology to specify or improve business processes models based on work practice descriptions.

  18. A model for website analysis and\tconception: the Website Canvas Model applied to\tEldiario.es

    Directory of Open Access Journals (Sweden)

    Carles Sanabre Vives

    2015-11-01

    Full Text Available This article presents the model of ideation and analysis called Website CanvasModel. It allows identifying the key aspects for a website to be successful, and shows how ithas been applied to Eldiario.es. As a result, the key factors prompting the success of thisdigital newspaper have been identified.

  19. Role of Facilities Available and Un-Available in Attracting of Tourist in Swat Valley Pakistan

    Directory of Open Access Journals (Sweden)

    Akbar Jalaluddin

    2017-01-01

    Full Text Available Natural landscape is an important resource for mountainous regions and play crucial role in tourism development. Tourism play a key role in economic development of a country. Developing tourist areas is the key to meet the expectations of mountain inhabitants, tourists, and the general public outside of mountainous areas. In order to know tourist perception, problems, and role of landscape & horticulture plants in the field of tourism. A research study entitled “Role of facilities available and un-available in attracting of tourist in swat valley Pakistan “The data was collected from the respondents through a questionnaire survey and analyzed using percentages, frequencies and Chi-square test (where applicable. The analyzed data revealed that most of the respondent (55 % considered natural green environment as a reason for their visit and 67 % respondents wanted to visit with their friends and were satisfied with the tourist area, respectively. Most of the respondent (39 % observed throwing of surplus food as major waste materials which turned the beautiful green environment into unattractive environment. Most of the visitors (52 % dislike un-cleanliness of the locality, 74% respondents felt ill effect due to deforestation.53 % tourist disagree with the current maintenance of the locality by tourism department. The most missed facilities were non availability of dustbins and children playing areas. 75 % respondents agreed with the fact that most of the people (local inhabitants as well as tourist were unaware with regard to maintenance activities of the area 15.7 % respondent agreed that road system should be improved to access most of the greenery in the locality, respectively to aware local people and tourist regarding maintenance of the locality will improve tourism in Swat valley. The studies need to be develop for the improvement of existing as well as artificial landscape of the tourist area (Kalam and Malamjabba of Swat valley.

  20. Application of genetic algorithm to land use optimization for non-point source pollution control based on CLUE-S and SWAT

    Science.gov (United States)

    Wang, Qingrui; Liu, Ruimin; Men, Cong; Guo, Lijia

    2018-05-01

    The genetic algorithm (GA) was combined with the Conversion of Land Use and its Effect at Small regional extent (CLUE-S) model to obtain an optimized land use pattern for controlling non-point source (NPS) pollution. The performance of the combination was evaluated. The effect of the optimized land use pattern on the NPS pollution control was estimated by the Soil and Water Assessment Tool (SWAT) model and an assistant map was drawn to support the land use plan for the future. The Xiangxi River watershed was selected as the study area. Two scenarios were used to simulate the land use change. Under the historical trend scenario (Markov chain prediction), the forest area decreased by 2035.06 ha, and was mainly converted into paddy and dryland area. In contrast, under the optimized scenario (genetic algorithm (GA) prediction), up to 3370 ha of dryland area was converted into forest area. Spatially, the conversion of paddy and dryland into forest occurred mainly in the northwest and southeast of the watershed, where the slope land occupied a large proportion. The organic and inorganic phosphorus loads decreased by 3.6% and 3.7%, respectively, in the optimized scenario compared to those in the historical trend scenario. GA showed a better performance in optimized land use prediction. A comparison of the land use patterns in 2010 under the real situation and in 2020 under the optimized situation showed that Shennongjia and Shuiyuesi should convert 1201.76 ha and 1115.33 ha of dryland into forest areas, respectively, which represented the greatest changes in all regions in the watershed. The results of this study indicated that GA and the CLUE-S model can be used to optimize the land use patterns in the future and that SWAT can be used to evaluate the effect of land use optimization on non-point source pollution control. These methods may provide support for land use plan of an area.