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Zhang, Ying, Jinliang Hou, Yongpan Cao, Juan Gu, and Chunlin Huang. "OpenMP parallelization of a gridded SWAT (SWATG)." Computers & Geosciences 109 (December 2017): 228–37. http://dx.doi.org/10.1016/j.cageo.2017.08.002.
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Michael, Mark A. "To Swat or Not to Swat." Environmental Ethics 18, no. 2 (1996): 165–80. http://dx.doi.org/10.5840/enviroethics199618230.
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Klein, George C. "Thinking SWAT." Journal of Police Crisis Negotiations 3, no. 1 (April 28, 2003): 59–83. http://dx.doi.org/10.1300/j173v03n01_05.
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Yusuf, Ilona. "from Swat." Journal of Postcolonial Writing 47, no. 2 (May 2011): 228–31. http://dx.doi.org/10.1080/17449855.2011.557241.
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Chapman, Suzy. "Virtual swat." New Scientist 213, no. 2856 (March 2012): 31. http://dx.doi.org/10.1016/s0262-4079(12)60699-x.
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Zare, Mohammad, Shahid Azam, and David Sauchyn. "A Modified SWAT Model to Simulate Soil Water Content and Soil Temperature in Cold Regions: A Case Study of the South Saskatchewan River Basin in Canada." Sustainability 14, no. 17 (August 30, 2022): 10804. http://dx.doi.org/10.3390/su141710804.
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Soil water content (SWC) and soil temperature are important hydrologic state variables. Accurate model simulation is critical in hydrologic regimes in cold regions dominated by spring snowmelt. In this study, we developed a combined physically-based soil temperature and energy-balance rain-on-snow (ROS) module for the Soil and Water Assessment Tool (SWAT) model and applied it to the South Saskatchewan River Basin (SSRB). We calibrated the SWAT base (SWAT-B) model and the SWAT modified (SWAT–M) model using daily measured soil temperature and SWC by hydrological response unit (HRU) for the years 2015 to 2020. The results of sensitivity analysis using the SUFI-2 technique in SWAT-CUP indicated that eight parameters have the most significant (p < 0.5) effect on streamflow, soil moisture, and snowmelt. Statistics for the SWAT-B and SWAT-M streamflow models revealed that the new module improved the Nash-Sutcliffe efficiency (NSE) from 0.39 to 0.71 and 0.42 to 0.76 for calibration and validation, respectively. The statistics for SWAT-simulated daily SWC showed that the measured data were a better fit with SWAT-M versus the SWAT-B output. Furthermore, SWAT-B values exceeded SWAT-M output and field measurements, and thus, the range of SWAT-M results was a better fit with observations. SWAT-B tended to underestimate soil temperature in the cold season, while SWAT-M significantly improved soil temperature simulation for winter. This new SWAT module simulated freeze-thaw cycles and captured the influence of snow cover on surface soil ice-water content. Spatial analysis of SWC and soil temperature across the SSRB showed that the SWAT-M model predicted more SWC and lower soil temperature in the western part of SSRB than SWAT-B, with higher soil temperature and lower SWC in the eastern region.
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Yuan, Lifeng, and Kenneth J. Forshay. "Evaluating Monthly Flow Prediction Based on SWAT and Support Vector Regression Coupled with Discrete Wavelet Transform." Water 14, no. 17 (August 27, 2022): 2649. http://dx.doi.org/10.3390/w14172649.
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Reliable and accurate streamflow prediction plays a critical role in watershed water resources planning and management. We developed a new hybrid SWAT-WSVR model based on 12 hydrological sites in the Illinois River watershed (IRW), U.S., that integrated the Soil and Water Assessment Tool (SWAT) model with a Support Vector Regression (SVR) calibration method coupled with discrete wavelet transforms (DWT) to better support modeling watersheds with limited data availability. Wavelet components of the simulated streamflow from the SWAT-Calibration Uncertainty Procedure (SWAT-CUP) and precipitation time series were used as inputs to SVR to build a hybrid SWAT-WSVR. We examined the performance and potential of the SWAT-WSVR model and compared it with observations, SWAT-CUP, and SWAT-SVR using statistical metrics, Taylor diagrams, and hydrography. The results showed that the average of RMSE-observation’s standard deviation ratio (RSR), Nash–Sutcliffe efficiency (NSE), percent bias (PBIAS), and root mean square error (RMSE) from SWAT-WSVR is 0.02, 1.00, −0.15, and 0.27 m3 s−1 in calibration and 0.14, 0.98, −1.88, and 2.91 m3 s−1 in validation on 12 sites, respectively. Compared with the other two models, the proposed SWAT-WSVR model possessed lower discrepancy and higher accuracy. The rank of the overall performance of the three SWAT-based models during the whole study period was SWAT-WSVR > SWAT-SVR > SWAT-CUP. The developed SWAT-WSVR model supplies an additional calibration approach that can improve the accuracy of the SWAT streamflow simulation of watersheds with limited data.
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Dzulfiqar, Muhammad Fakhri, and Asep Sapei. "Kinerja Program Soil and Water Assessment Tools (SWAT) yang Dimodifikasi untuk Menduga Debit Sub-DAS Cimanuk Hulu." Jurnal Teknik Sipil dan Lingkungan 8, no. 03 (December 28, 2023): 157–66. http://dx.doi.org/10.29244/jsil.8.03.157-166.
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Soil and Water Assessment Tool (SWAT) merupakan sebuah model hidrologi yang dikembangkan di Amerika Serikat untuk menganalisis dampak dari perubahan tata guna lahan terhadap hasil air (debit) dan sedimentasi. Model ini telah banyak diterapkan di Asia. Akan tetapi, neraca air di dalam model SWAT menggunakan neraca air untuk tanaman yang ditanam pada lahan kering (up land) termasuk tanaman padi. Di Asia, khususnya di Indonesia, tanaman padi umumnya ditanam di lahan sawah. Untuk menyesuaikan dengan kondisi lahan sawah, model SWAT telah dimodifikasi dengan mengacu kepada algoritma sawah yang dikembangkan oleh Sakaguchi et.al. (2014). Penelitian ini bertujuan untuk mengevaluasi kinerja model SWAT yang dimodifikasi untuk menduga debit Sub-DAS Cimanuk Hulu yang bersawah. Hasil evaluasi menunjukkan bahwa model SWAT yang dimodifikasi dapat menduga debit relative lebih baik dibandingkan dengan modul SWAT original (tanpa algoritma sawah) yang ditunjukkan oleh nilai determinasi (R2) dan Nash-Sutcliffe efficiency (NSE). Nilai R2 dari hasil kalibrasi model SWAT yang dimodifikasi, SWAT original lahan kering dan model SWAT pot-hole berturut-turut adalah 0.569, 0.494 dan 0.544. Sedangkan nilai NSE dari hasil kalibrasi model SWAT yang dimodifikasi, SWAT original lahan kering dan model SWAT pot-hole berturut-turut adalah 0.521, 0.420 dan 0.503
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Gunn, Kpoti M., Anthony R. Buda, Heather E. Preisendanz, Raj Cibin, Casey D. Kennedy, and Tamie L. Veith. "Integrating Daily CO2 Concentrations in SWAT-VSA to Examine Climate Change Impacts on Hydrology in a Karst Watershed." Transactions of the ASABE 64, no. 4 (2021): 1303–18. http://dx.doi.org/10.13031/trans.13711.
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HighlightsWe used SWAT-VSA to assess the effects of climate change with rising CO2 on the water balance of a karst basin.For future climate, SWAT-VSA with rising CO2 yielded 7.1% less ET and 6.3% more runoff than standard SWAT-VSA.Rising CO2 also affected variable source areas, with greater ET declines and runoff increases in the wettest soils.Findings suggest CO2 effects on water balance should be included in future climate change studies with SWAT-VSA.Abstract. Characterizing the effects of climate change on hydrology is important to watershed management. In this study, we used SWAT-VSA to examine the effects of climate change and increasing atmospheric CO2 (CO2) on the water balance of Spring Creek watershed, a mixed land-use karst basin in the Upper Chesapeake Bay watershed. First, we modified the stomatal conductance and leaf area index (LAI) routines of SWAT-VSA’s Penman-Monteith evapotranspiration (ET) procedure and enabled the model to accept daily CO2 data. Using downscaled climate projections from nine global climate models (GCMs), we then compared water balance estimations from baseline SWAT-VSA against two modified versions of SWAT-VSA. One SWAT-VSA version integrated daily CO2 levels (SWAT-VSA_CO2), while another version added flexible stomatal conductance and LAI routines (SWAT-VSA_CO2+Plant) to the dynamic CO2 capacity. Under current climate (1985-2015), the three SWAT-VSA models produced generally similar water balance estimations, with 51% of precipitation lost to ET and the remainder converted to runoff (10%), lateral flow (9%), and percolate (30%). For future climate (2020-2065), water balance simulations diverged between baseline SWAT-VSA and the two modified SWAT-VSA models with CO2. Notably, variable stomatal conductance and LAI routines produced no detectable effects beyond that of CO2. For the 2020-2065 period, baseline SWAT-VSA projected ET increases of 0.7 mm year-1, while SWAT-VSA models with CO2 suggested that annual ET could decline by approximately -0.4 mm year-1 over the same period. As a result, the two CO2-based SWAT-VSA models predicted streamflow increases of almost 1.6 mm year-1 over the 2020-2065 period, which were roughly double the streamflow increases projected by baseline SWAT-VSA. In general, SWAT-VSA models with CO2 effects produced 22.4% more streamflow in 2045-2065 than the SWAT-VSA model without CO2. Results also showed that adding daily CO2 to SWAT-VSA reduced ET in wetter parts of Spring Creek watershed, leading to greater runoff losses from variable source areas compared to baseline SWAT-VSA. Findings from the study highlight the importance of considering increasing atmospheric CO2 concentrations in water balance simulations with SWAT-VSA in order to gain a fuller appreciation of the hydrologic uncertainties with climate change. Keywords: Carbon dioxide, Climate change, Hydrologic model, Water balance, Watershed.
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Fausan, Ahmad, Asep Sapei, Yuli Suharnoto, and Nora Herdiana Pandjaitan. "Analysis of Maros River Discharge Using the Modified Soil and Water Assessment Tools (SWAT) Program." Jurnal Teknik Pertanian Lampung (Journal of Agricultural Engineering) 11, no. 1 (March 31, 2022): 146. http://dx.doi.org/10.23960/jtep-l.v11i1.146-160.
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Soil and Water Assessment Tools (SWAT) which is developed in America was used to analyze the effect of land management on discharge, sedimentation, and water quality in a river basin area. The hydrological conditions in the Americas are different from Indonesia, so a modified SWAT is done. This research aimed to implement a modified SWAT program to predict the results of a better discharge analysis based on hydrological analysis in the sub-Watershed area. About 13.90% of the area was paddy fields. The evaluation of the module had been done by looking at the coefficient of determination (R²) and Nash-Sutcliffe Efficiency (NSE) based on the comparison of simulated discharge results with an observation discharge. Research began with delineation DEM, HRU formation, simulation, calibration, and validation. The R² value for daily data on modified SWAT was 0,725. It was better than the original SWAT and SWAT with Pothole, which were 0,706 and 0,708 respectively. Likewise, the NSE value for daily data on modified SWAT was 0,721, on original SWAT and on SWAT with Pothole was 0,668 and 0,685 respectively. The analysis result showed that the modified SWAT provide good discharge prediction results, indicated by relatively high R2 and NSE values.Keywords: hydrological analysis,modified SWAT, paddy field, pothole, SWAT
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Weiss, Rick. "The Swat Team." Science News 137, no. 5 (February 3, 1990): 72. http://dx.doi.org/10.2307/3974379.
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Olivera, Francisco, Milver Valenzuela, R. Srinivasan, Janghwoan Choi, Hiudae Cho, Srikanth Koka, and Ashish Agrawal. "ARCGIS-SWAT: A GEODATA MODEL AND GIS INTERFACE FOR SWAT." Journal of the American Water Resources Association 42, no. 2 (April 2006): 295–309. http://dx.doi.org/10.1111/j.1752-1688.2006.tb03839.x.
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Molina-Navarro, Eugenio, Ryan T. Bailey, Hans Estrup Andersen, Hans Thodsen, Anders Nielsen, Seonggyu Park, Jacob Skødt Jensen, Jacob Birk Jensen, and Dennis Trolle. "Comparison of abstraction scenarios simulated by SWAT and SWAT-MODFLOW." Hydrological Sciences Journal 64, no. 4 (March 12, 2019): 434–54. http://dx.doi.org/10.1080/02626667.2019.1590583.
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Yen, Haw, Seonggyu Park, Jeffrey G. Arnold, Raghavan Srinivasan, Celray James Chawanda, Ruoyu Wang, Qingyu Feng, et al. "IPEAT+: A Built-In Optimization and Automatic Calibration Tool of SWAT+." Water 11, no. 8 (August 14, 2019): 1681. http://dx.doi.org/10.3390/w11081681.
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For almost 30 years, the Soil and Water Assessment Tool (SWAT) has been successfully implemented to address issues around various scientific subjects in the world. On the other hand, it has been reaching to the limit of potential flexibility in further development by the current structure. The new generation SWAT, dubbed SWAT+, was released recently with entirely new coding features. SWAT+ is designed to have far more advanced functions and capacities to handle challenging watershed modeling tasks for hydrologic and water quality processes. However, it is still inevitable to conduct model calibration before the SWAT+ model is applied to engineering projects and research programs. The primary goal of this study is to develop an open-source, easy-to-operate automatic calibration tool for SWAT+, dubbed IPEAT+ (Integrated Parameter Estimation and Uncertainty Analysis Tool Plus). There are four major advantages: (i) Open-source code to general users; (ii) compiled and integrated directly with SWAT+ source code as a single executable; (iii) supported by the SWAT developer group; and, (iv) built with efficient optimization technique. The coupling work between IPEAT+ and SWAT+ is fairly simple, which can be conducted by users with minor efforts. IPEAT+ will be regularly updated with the latest SWAT+ revision. If users would like to integrate IPEAT+ with various versions of SWAT+, only few lines in the SWAT+ source code are required to be updated. IPEAT+ is the first automatic calibration tool integrated with SWAT+ source code. Users can take advantage of the tool to pursue more cutting-edge and forward-thinking scientific questions.
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Her, Younggu, and Jeahak Jeong. "SWAT+ versus SWAT2012: Comparison of Sub-Daily Urban Runoff Simulations." Transactions of the ASABE 61, no. 4 (2018): 1287–95. http://dx.doi.org/10.13031/trans.12600.
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Abstract. The current FORTRAN code of SWAT (SWAT2012) is being rebuilt to ease new model and module development by incorporating object-oriented programming techniques into defining spatial objects and calculating variables. SWAT+, the new SWAT code, is expected to offer flexible watershed representation with linked spatial objects. Ideally, SWAT+ produces outputs that are comparable to SWAT2012, if not identical, when the two versions of SWAT are set with the same input for a watershed. However, the drastic restructuring of the source code may cause unexpected results in the output, especially when compared with the current SWAT2012 model that has a long history of model validation. In this technical note, we compare sub-daily, daily, and monthly hydrographs provided by SWAT2012 and SWAT+ that were prepared for a small urban watershed in Austin, Texas. The model parameters were calibrated to 15 min and daily runoff observed in the watershed. SWAT+ was on par with SWAT2012 in predicting streamflow at daily and monthly scales. However, the HRU-level flow routing scheme newly added to SWAT+ created multiple peaks in the sub-daily hydrographs, suggesting a need to further improve the water transport simulation strategies. This technical note provides ideas of how SWAT+ is organized and if a SWAT modeler can maintain consistency in modeling results when shifting from the original code to the new code. In addition, this technical note discusses the potential for improved SWAT+ modeling. Keywords: Model calibration, Storm event, Sub-daily simulation, SWAT, Urban watershed.
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Zhang, Dejian, Wenjie Fu, Qiaoying Lin, and Xingwei Chen. "WOF-SWAT: A Web-Based Open-Source Framework for Investigating the Hydrological Impacts of Climate Change and Human Activities Through Online Simulation and Visualization of SWAT Models." ISPRS International Journal of Geo-Information 8, no. 9 (August 23, 2019): 368. http://dx.doi.org/10.3390/ijgi8090368.
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This study developed a web-based open-source framework based on the Soil and Water Assessment Tool (SWAT), named WOF-SWAT (web-based open-source framework for SWAT), to investigate individual and combined impacts of climate change, land use change, and point-source pollutants on watershed-scale hydrological and chemical processes. The architecture, workflows, interfaces, and key processes of WOF-SWAT are described and discussed. Using a previously developed well-calibrated hydrological model of the Jinjiang River basin, four scenarios were simulated in WOF-SWAT and other traditional desktop-based tools (i.e., ArcSWAT and SWAT-CUP) to examine the credibility, efficiency, and functionality of WOF-SWAT. The results show that, in combination with a well-calibrated watershed model, WOF-SWAT is sufficiently sound and reasonable to investigate individual and combined impacts of climate change, land use change, and point-source pollutants. We thus conclude that WOF-SWAT can be used as a substitute for other tools to carry out similar tasks in a web-based environment while providing more user-friendly interfaces, accessibility, and efficiency. We also discuss ongoing and possible future efforts to develop WOF-SWAT into a fully-fledged watershed research and management framework.
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Nguyen, Van, Jörg Dietrich, Bhumika Uniyal, and Dang Tran. "Verification and Correction of the Hydrologic Routing in the Soil and Water Assessment Tool." Water 10, no. 10 (October 10, 2018): 1419. http://dx.doi.org/10.3390/w10101419.
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The Soil and Water Assessment Tool (SWAT) is one of the most widely used eco-hydrological models. SWAT has been undergoing constant changes since its development. However, compartment review and testing of SWAT, especially the hydrologic routing functions, are comparably limited. In this study, the daily hydrologic routing subroutines of different SWAT versions were reviewed and tested using a well observed segment of the Weser River located in Germany. Results show several problems with the routing subroutines of SWAT. The variable storage subroutine of SWAT (Revision 664) does not transform the stream flow. Unphysical results could be obtained with the variable storage routing of SWAT (Revision 528). The Muskingum subroutine of SWAT (Revisions 664 and 528) overestimates daily channel evaporation (resulting in a bias of up to 6.3% in streamflow in our case studies) and underestimates daily transmission losses. Simulated results show that the timing and shape of flood waves, as well as the volume of low flows, could be improved with a corrected Muskingum subroutine. Based on the results of this study, we suggest that the SWAT user community review their existing SWAT models to see how the aforementioned issues will affect their methods, findings, and conclusions.
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Upadhyay, Pawan, Anna Linhoss, Chris Kelble, Steve Ashby, Naja Murphy, and Prem B. Parajuli. "Applications of the SWAT Model for Coastal Watersheds: Review and Recommendations." Journal of the ASABE 65, no. 2 (2022): 453–69. http://dx.doi.org/10.13031/ja.14848.
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HighlightsA systematic review was performed of SWAT applications in coastal watersheds.Three percent of SWAT applications have occurred in coastal watersheds.SWAT performed better at a monthly time step versus a daily time step.Nash-Sutcliffe efficiency (NSE) was the most common metric used for evaluating simulations.More research should be conducted on coupling SWAT with hydrodynamic models in tidal systems.Abstract. The Soil and Water Assessment Tool (SWAT) is a watershed to river basin scale model widely used to simulate the quality and quantity of surface water and groundwater. SWAT has been applied in a wide variety of geographical landscapes around the world. This review presents a comprehensive summary of SWAT applications for coastal watersheds. Thirty-four articles were identified as coastal applications of SWAT, which account for 3% of the total published studies using SWAT. Nash-Sutcliffe efficiency (NSE) was the most common metric used to evaluate SWAT simulations. The SWAT model calibration and validation studies in coastal watersheds reported higher NSE values for monthly flow simulation (NSE up to 0.95) than for daily flow simulation (NSE up to 0.89). Among all the studies, 34% of the reported NSE values (flow and water quality combined) were >0.75. The majority (58%) of flow values were reported daily, while the majority (81%) of water quality values were reported monthly. Only two studies combined SWAT with a hydrodynamic model to account for tide-storm surge processes. SWAT may be applied more readily and successfully to coastal watersheds if a user-friendly method is developed for coupling SWAT with hydrodynamic models to simulate the tidal influence. Keywords: Bay, Coast, Estuary, Gulf, Hydrologic model, Soil and Water Assessment Tool, Water quality model, Watershed model.
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Shao, Guangwen, Danrong Zhang, Yiqing Guan, Yuebo Xie, and Feng Huang. "Application of SWAT Model with a Modified Groundwater Module to the Semi-Arid Hailiutu River Catchment, Northwest China." Sustainability 11, no. 7 (April 5, 2019): 2031. http://dx.doi.org/10.3390/su11072031.
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In the original soil and water assessment Tool (SWAT) model (SWAT-O), the contributions of shallow aquifers and deep aquifers to streamflow are simulated using the linear reservoir method. The movement of groundwater was limited in the hydrological response unit which is a minimum calculation unit in the SWAT. However, this computational method may not be suitable for the areas where a groundwater system is complicated, and the river is predominately recharged by groundwater. In this paper, we proposed an enhanced groundwater module which divides shallow aquifers into upper and lower aquifers, integrates all the deep aquifers of a sub-basin into a regional aquifer, and simulates interactive water amount between lower aquifer and deep aquifer using water depth difference. The modified groundwater module was introduced to the original SWAT model, hereby referred to as SWAT-MG. The SWAT-MG and SWAT-O models were applied to the Hailiutu River catchment, which is a semi-arid wind sandy grass shoal catchment. Results showed that both models underestimated streamflow in peak flow, while the simulated streamflow of SWAT-MG was closer the observed values than that of SWAT-O. Three evaluation criteria (NSE, RSR, PBIAS) were applied to evaluate the performance of the models and the results showed that SWAT-MG had a better performance than SWAT-O. The baseflow index of Hailiutu River which was calculated by the results of SWAT-MG was 96.78%, which means the streamflow is predominately recharged by groundwater, and this conforms to the actual situation of Hailiutu River catchment. This indicates that a SWAT model with a modified groundwater module could better represent the groundwater flow behavior in the study area.
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Bo, Huijuan, Xiaohua Dong, Zhonghua Li, Gebrehiwet Reta, Lu li, and Chong Wei. "Comparison of Two Versions of SWAT Models in Predicting the Streamflow in the Xuanmiaoguan Reservoir Catchment." Nature Environment and Pollution Technology 21, no. 2 (June 1, 2022): 529–41. http://dx.doi.org/10.46488/nept.2022.v21i02.011.
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Correct streamflow prediction is critical for determining the availability and efficiency of watershed spatial plans and water resource management. In the Xuanmiaoguan (XMG) Reservoir Catchment, two different versions of the Soil and Water Assessment Tool (SWAT) model are compared to discharge predictions. One version is the Topo-SWAT, in which the overland flow is generated by saturation excess (Dunne) runoff mechanism, while the other is driven by infiltration excess runoff mechanism, i.e., the Regular-SWAT. These SWAT models were calibrated and validated with discharge at daily and monthly steps, and then, the annual runoff volume and spatial distribution of runoff generation areas were also discussed. At the monthly scale, the un-calibrated Topo-SWAT model outperformed the un-calibrated Regular-SWAT model throughout the whole time (2010-2016). The Nash-Sutcliffe efficiency coefficients (NSE) using Topo-SWAT and Regular-SWAT were 0.59, 0.58 for calibration and 0.69, 0.72 for validation for daily streamflow, and 0.69, 0.65 for calibration and 0.73, 0.88 for validation for monthly streamflow, respectively, based on the parameter sensitivity analysis results. There was a 5-year understatement for yearly runoff volume using Regular-SWAT, but a 4-year underestimation using Topo-SWAT, which had a different year in 2015. Regular-SWAT and Topo-SWAT have significantly different geographical distributions of runoff generating locations within the watershed for one occurrence (greater rainfall). The findings reveal the most accurate contributing regions for runoff generation in the research catchment, allowing for more effective implementation of best management techniques (BMPs).
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Steenhuis, Tammo S., Elliot M. Schneiderman, Rajith Mukundan, Linh Hoang, Mamaru Moges, and Emmet M. Owens. "Revisiting SWAT as a Saturation-Excess Runoff Model." Water 11, no. 7 (July 11, 2019): 1427. http://dx.doi.org/10.3390/w11071427.
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The Soil Water Assessment Tool (SWAT) is employed throughout the world to simulate watershed processes. A limitation of this model is that locations of saturation excess overland flow in hilly and mountainous regions with an impermeable layer at shallow depth cannot be simulated realistically. The objective of this research is to overcome this limitation with minor changes in the original SWAT code. The new approach is called SWAT-with-impervious-layers (SWAT-wil). Adaptations consisted of redefining the hillslope length, restricting downward percolation from the root zone, and redefining hydrologic response units (HRUs) such that they are associated with the landscape position. Finally, input parameters were chosen such that overland flow from variable saturated areas (VSAs) corresponds to the variable source interpretation of the Soil Conservation Service (SCS) curve number runoff equation. We tested the model for the Town Brook watershed in the Catskill Mountains. The results showed that the discharge calculated with SWAT-wil agreed with observed outflow and results simulated with the original SWAT and SWAT-hillslope (SWAT-HS) models that had a surface aquifer that transferred water between groups of HRUs. The locations of the periodically saturated runoff areas were predicted by SWAT-wil at the right locations. Current users can utilize the SWAT-wil approach for catchments where VSA hydrology predominates.
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Lee, Chang-Hun, Namjoo Lee, and Jong-Tae Kim. "SWAT model calibration/validation using SWAT-CUP in Danjang-stream watershed." Journal of the Korea Academia-Industrial cooperation Society 22, no. 9 (September 30, 2021): 235–46. http://dx.doi.org/10.5762/kais.2021.22.9.235.
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Williams, Jimmy J., and David Westall. "SWAT and non-SWAT police officers and the use of force." Journal of Criminal Justice 31, no. 5 (September 2003): 469–74. http://dx.doi.org/10.1016/s0047-2352(03)00051-5.
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Fu, Congsheng, April L. James, and Huaxia Yao. "SWAT-CS: Revision and testing of SWAT for Canadian Shield catchments." Journal of Hydrology 511 (April 2014): 719–35. http://dx.doi.org/10.1016/j.jhydrol.2014.02.023.
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Meng, Xianyong, Xuesong Zhang, Mingxiang Yang, Hao Wang, Ji Chen, Zhihua Pan, and Yiping Wu. "Application and Evaluation of the China Meteorological Assimilation Driving Datasets for the SWAT Model (CMADS) in Poorly Gauged Regions in Western China." Water 11, no. 10 (October 18, 2019): 2171. http://dx.doi.org/10.3390/w11102171.
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The temporal and spatial differentiation of the underlying surface in East Asia is complex. Due to a lack of meteorological observation data, human cognition and understanding of the surface processes (runoff, snowmelt, soil moisture, water production, etc.) in the area have been greatly limited. With the Heihe River Basin, a poorly gauged region in the cold region of Western China, selected as the study area, three meteorological datasets are evaluated for their suitability to drive the Soil and Water Assessment Tool (SWAT): China Meteorological Assimilation Driving Datasets for the SWAT model (CMADS), Climate Forecast System Reanalysis (CFSR), and Traditional Weather Station (TWS). Resultingly, (1) the runoff output of CMADS + SWAT mode is generally better than that of the other two modes (CFSR + SWAT and TWS + SWAT) and the monthly and daily Nash–Sutcliffe efficiency ranges of the CMADS + SWAT mode are 0.75–0.95 and 0.58–0.77, respectively; (2) the CMADS + SWAT and TWS + SWAT results were fairly similar to the actual data (especially for precipitation and evaporation), with the results produced by CMADS + SWAT lower than those produced by TWS + SWAT; (3) the CMADS + SWAT mode has a greater ability to reproduce water balance than the other two modes. Overestimation of CFSR precipitation results in greater error impact on the uncertainty output of the model, whereas the performances of CMADS and TWS are more similar. This study addresses the gap in the study of surface processes by CMADS users in Western China and provides an important scientific basis for analyzing poorly gauged regions in East Asia.
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Kakarndee, Isared, and Ekasit Kositsakulchai. "Comparison between SWAT and SWAT+ for simulating streamflow in a paddy-field-dominated basin, northeast Thailand." E3S Web of Conferences 187 (2020): 06002. http://dx.doi.org/10.1051/e3sconf/202018706002.
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The performance of the well-known Soil and Water Assessment Tool (SWAT) and the new SWAT+ for streamflow simulation in a paddy- field-dominated basin was compared. The Lam Sioa River Basin, northeast Thailand (drainage area of 3,394 km2) was selected. The data inputs consisted of DEM, land use, soil, and climate (rainfall, temperature, sunshine hour, wind speed and humidity). The model parameters used the default values from SWAT database and daily simulation was conducted from 2005 to 2017. The division of sub-basins into “landscape units” is one of new features of SWAT+. The total number of HRUs defined from SWAT+ were higher than those from SWAT because the sub-basins derived from SWAT+ contained two landscape units (floodplain and upslope). With the default model parameters, the model performance indicators were found below the satisfactory rating. Both models simulated relatively high streamflow at the beginning of rainy season, while the observed streamflow was still not occurred. In paddy field, rainfall excess become ponding water, not surface runoff. The appropriate representation of paddy field in SWAT model should be further investigated.
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Karki, Ritesh, Puneet Srivastava, and Tamie L. Veith. "Application of the Soil and Water Assessment Tool (SWAT) at Field Scale: Categorizing Methods and Review of Applications." Transactions of the ASABE 63, no. 2 (2020): 513–22. http://dx.doi.org/10.13031/trans.13545.
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HighlightsThis review study identified five different ways of setting up a SWAT model for field-scale analysis.Model setup for each field-scale modeling method and examples of application are discussed.Benefits and limitations of each method are discussed.Abstract. Although the Soil and Water Assessment Tool (SWAT) has been widely used as a watershed/basin scale model, recently there has been considerable interest in applying it at the field scale, especially for evaluation of best management practices and for building stakeholder confidence. In this study, a thorough review of the literature on field-scale application of SWAT was conducted. It was determined that there is more than one way of setting up a field-scale SWAT model depending on the spatial scale of the research as well as the research question to be answered. This article provides a detailed review of the methods used for field-scale SWAT modeling along with a summary of applications. This article also discusses the limitations and advantages of each method along with future research needs. The overarching goal of this article is to provide a valuable and time-conserving resource for future researchers interested in field-scale SWAT modeling. Keywords: Arc-SWAT, Field level, Field-scale resolution, Field-scale SWAT, SWAT.
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Rahma Yanti, Nika, Rusnam Rusnam, and Eri Gas Ekaputra. "ANALISIS DEBIT PADA DAS AIR DINGIN MENGGUNAKAN MODEL SWAT." Jurnal Teknologi Pertanian Andalas 21, no. 2 (September 1, 2017): 127. http://dx.doi.org/10.25077/jtpa.21.2.127-137.2017.
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Perubahan penggunaan lahan dari lahan bervegetasi ke non vegetasi mengakibatkan besarnya limpasan (run off) sehingga debit menjadi meningkat terutama pada musim hujan. Penelitian ini dilakukan untuk menganalisis debit pada DAS Air Dingin menggunakan model SWAT dan apakah model SWAT dapat diterapkan dalam mempresentasikan debit pada DAS Air Dingin. Model SWAT memerlukan data iklim, peta dan data tanah, curah hujan, kelerengan dan peta penggunaan lahan. Adapun tahapan yang dilakukan yaitu penyiapan data dan peta, deliniasi DAS, pembentukan HRU, simulasi visualisasi, kalibrasi, dan simulasi dengan model SWAT terkalibrasi. Debit DAS Air Dingin berkisar antara 3 – 30 m3/s. Setelah dilakukan kalibrasi model SWAT dapat mempresentasikan keadaan hidrologi DAS Air Dingin dengan R2 0,76 dan NS 0,64 sehingga model SWAT yang dijalankan dapat dikategorikan memuaskan.
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Duane, Sinead, Akke Vellinga, Valerie Smith, Marie Tierney, Claire Beecher, Megan Burke, Andrew W. Murphy, and Declan Devane. "The effectiveness of digital multimedia presentation of trial information on recruitment and retention of patients: Protocol for a study within a trial (SWAT)." HRB Open Research 3 (March 30, 2020): 10. http://dx.doi.org/10.12688/hrbopenres.12994.1.
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Background: Studies within trials (SWATs) present an opportunity to examine design factors that may impact on the successful delivery of trials. One area in need of research is trial recruitment. Recruiting patients to trials is a major challenge facing trialists. Failure to meet recruitment targets can result in delays and underpowered studies. This SWAT evaluates the effectiveness of hand-held digital multimedia presentation of trial information and standard written patient information to potential participants on recruitment and retention to a host trial. Methods: This is the protocol for SWAT 15, a two-group, embedded parallel randomised controlled trial (RCT) (ISRCTN12838042) designed within a host trial - the SATIN trial (ISRCTN88111427), a RCT designed for implementation in the Irish primary care setting. The SWAT eligibility criteria was determined by the host trial. General practices who agree to participate in the host trial will provide women (participants) who are willing to consider participating in the host trial with either a multimedia digital information resource facilitated through a handheld tablet device, plus a written participant information leaflet (Intervention) or a written participant information leaflet (comparator). Outcomes are recruitment and retention to the host SATIN trial and participant’s quality of decision-making. Discussion: Although designed to be implemented in a host trial, the host trial, was suspended and therefore this SWAT was not implemented. The protocol and the lessons learnt whilst developing it offer guidance to researchers who wish to answer similar research questions in the future in a similar context or setting. Trial registration: ISRCTN Registry ISRCTN12838042 (11/10/2017)
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Yuan, Lifeng, and Kenneth J. Forshay. "Enhanced streamflow prediction with SWAT using support vector regression for spatial calibration: A case study in the Illinois River watershed, U.S." PLOS ONE 16, no. 4 (April 12, 2021): e0248489. http://dx.doi.org/10.1371/journal.pone.0248489.
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Accurate streamflow prediction plays a pivotal role in hydraulic project design, nonpoint source pollution estimation, and water resources planning and management. However, the highly non-linear relationship between rainfall and runoff makes prediction difficult with desirable accuracy. To improve the accuracy of monthly streamflow prediction, a seasonal Support Vector Regression (SVR) model coupled to the Soil and Water Assessment Tool (SWAT) model was developed for 13 subwatersheds in the Illinois River watershed (IRW), U.S. Terrain, precipitation, soil, land use and land cover, and monthly streamflow data were used to build the SWAT model. SWAT Streamflow output and the upstream drainage area were used as two input variables into SVR to build the hybrid SWAT-SVR model. The Calibration Uncertainty Procedure (SWAT-CUP) and Sequential Uncertainty Fitting-2 (SUFI-2) algorithms were applied to compare the model performance against SWAT-SVR. The spatial calibration and leave-one-out sampling methods were used to calibrate and validate the hybrid SWAT-SVR model. The results showed that the SWAT-SVR model had less deviation and better performance than SWAT-CUP simulations. SWAT-SVR predicted streamflow more accurately during the wet season than the dry season. The model worked well when it was applied to simulate medium flows with discharge between 5 m3 s-1 and 30 m3 s-1, and its applicable spatial scale fell between 500 to 3000 km2. The overall performance of the model on yearly time series is “Satisfactory”. This new SWAT-SVR model has not only the ability to capture intrinsic non-linear behaviors between rainfall and runoff while considering the mechanism of runoff generation but also can serve as a reliable regional tool for an ungauged or limited data watershed that has similar hydrologic characteristics with the IRW.
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Yu, Dan, Ping Xie, Xiaohua Dong, Xiaonong Hu, Ji Liu, Yinghai Li, Tao Peng, Haibo Ma, Kai Wang, and Shijin Xu. "Improvement of the SWAT model for event-based flood simulation on a sub-daily timescale." Hydrology and Earth System Sciences 22, no. 9 (September 27, 2018): 5001–19. http://dx.doi.org/10.5194/hess-22-5001-2018.
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Abstract. Flooding represents one of the most severe natural disasters threatening the development of human society. A model that is capable of predicting the hydrological responses in watershed with management practices during flood period would be a crucial tool for pre-assessment of flood reduction measures. The Soil and Water Assessment Tool (SWAT) is a semi-distributed hydrological model that is well capable of runoff and water quality modeling under changed scenarios. The original SWAT model is a long-term yield model. However, a daily simulation time step and a continuous time marching limit the application of the SWAT model for detailed, event-based flood simulation. In addition, SWAT uses a basin level parameter that is fixed for the whole catchment to parameterize the unit hydrograph (UH), thereby ignoring the spatial heterogeneity among the sub-basins when adjusting the shape of the UHs. This paper developed a method to perform event-based flood simulation on a sub-daily timescale based on SWAT2005 and simultaneously improved the UH method used in the original SWAT model. First, model programs for surface runoff and water routing were modified to a sub-daily timescale. Subsequently, the entire loop structure was broken into discrete flood events in order to obtain a SWAT-EVENT model in which antecedent soil moisture and antecedent reach storage could be obtained from daily simulations of the original SWAT model. Finally, the original lumped UH parameter was refined into a set of distributed ones to reflect the spatial variability of the studied area. The modified SWAT-EVENT model was used in the Wangjiaba catchment located in the upper reaches of the Huaihe River in China. Daily calibration and validation procedures were first performed for the SWAT model with long-term flow data from 1990 to 2010, after which sub-daily (Δt=2 h) calibration and validation in the SWAT-EVENT model were conducted with 24 flood events originating primarily during the flood seasons within the same time span. Daily simulation results demonstrated that the SWAT model could yield very good performances in reproducing streamflow for both whole year and flood period. Event-based flood simulation results simulated by the sub-daily SWAT-EVENT model indicated reliable performances, with ENS values varying from 0.67 to 0.95. The SWAT-EVENT model, compared to the SWAT model, particularly improved the simulation accuracies of the flood peaks. Furthermore, the SWAT-EVENT model results of the two UH parameterization methods indicated that the use of the distributed parameters resulted in a more reasonable UH characterization and better model fit compared to the lumped UH parameter.
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Dinakhel, Muhammad Ali. "Swat State and Bolshevik Movement." Central Asia 85, Winter (April 20, 2020): 95–117. http://dx.doi.org/10.54418/ca-85.13.
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Swat State was formally established in 1915 by the first ruler of Swat State, Syed Abdul Jabar Shah. In the month of September 1917 he was dethroned on account of his alleged attachment with Qadyani/Ahmadi sect. After his removal from rule and subsequent exile, Miangul Abdul Wadud was installed as ruler of Swat in the month of September 1917. Swat State was recognized by the British Government in 1926. The recognition was granted with the condition that the state’s rulers will not act against the British Government. When in 1917 the Bolshevik Movement emerged in Russia, it also influenced Swat and surrounding areas. Some people were found here who had affiliation with Bolshevik Movement. The colonial government’s confidential records also show that some people of Swat were involved in secret activities of Bolshevik Movement. This article analyzes the expansion of Bolshevik Movement from Russia and Central Asia via Afghanistan to the frontier regions including Swat State. This paper also describes the steps taken by the British Government to control the activities of this movement.
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Tsuchiya, Ryota, Tasuku Kato, Jaehak Jeong, and Jeffrey Arnold. "Development of SWAT-Paddy for Simulating Lowland Paddy Fields." Sustainability 10, no. 9 (September 11, 2018): 3246. http://dx.doi.org/10.3390/su10093246.
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The recent increase in global consumption of rice has led to increased demand for sustainable water management in paddy cultivation. In this study, we propose an enhanced paddy simulation module to be introduced to Soil and Water Assessment Tool (SWAT) to evaluate the sustainability of paddy cultivation. The enhancements added to SWAT include: (1) modification of water balance calculation for impounded fields, (2) addition of an irrigation management option for paddy fields that are characterized by flood irrigation with target water depth, and (3) addition of a puddling operation that influences the water quality and infiltration rate of the top soil layer. In a case study, the enhanced model, entitled SWAT-Paddy, was applied to an agricultural watershed in Japan. The results showed that the SWAT-Paddy successfully represented paddy cultivation, water management, and discharge processes. Simulated daily discharge rates with SWAT-Paddy (R2 = 0.8) were superior to the SWAT result (R2 = 0.002). SWAT-Paddy allows the simulation of paddy management processes realistically, and thus can enhance model accuracy in paddy-dominant agricultural watersheds.
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Azim, Syed Wasif, Wajid Mehmood, and Sajjad Hussain. "Swat Conflict in Retrospect: Violence and Jarga among the Swat Pukhtuns in Pakistan." Liberal Arts and Social Sciences International Journal (LASSIJ) 2, no. 1 (June 30, 2018): 37–48. http://dx.doi.org/10.47264/idea.lassij/2.1.5.
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Violent conflicts have perpetual and perennial impacts on societies. Culture and ethnic identities of the people are no exception. This study reflects the impacts of conflict and violence on culture, specifically a single cultural code known as Jarga. Methodologically, the study is based on an ethnographic fieldwork, comprised of 45 open-ended and in-depth interviews, five Focus Group Discussions and personal observation in Swat. Through the conflict in Swat and Pukhtun cultural code of Jarga, it contends that the conflict and violence in Swat has multiple and significant impacts for Jarga. Jarga on higher level, like the Swat Qaumi Jarga (Swat National Jarga) has been more active since the conflict started in 2007, while Jarga on lower (village) level has lost its practice in many areas of Swat. Militants and Pakistani state have been often involved in forming, using, and manipulating Jargas in Swat amidst the conflict. Moreover, the conflict has repercussions for Tanzeems (local organizations) and committees, which were sharing work and place with Jarga in Swat. The state institutions have introduced Village Defence Committees which have bypassed all the existing committees and organizations mainly due to their enhanced powers. These processes have added to ‘defaming’ the cultural ideals, which is socially an unacceptable and detrimental development for Pukhtun society. It has been concluded that conflict and violence impact the markers and codes of cultural and ethnic distinctiveness.
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Young, Andrew T., Chris Hennington, and Dane Eggleston. "US SWAT operator experience, personality, cognitive-emotion regulation and decision-making style." Policing: An International Journal 41, no. 2 (April 9, 2018): 247–61. http://dx.doi.org/10.1108/pijpsm-10-2016-0156.
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Purpose The purpose of this paper is to examine SWAT operator deployment experience, personality, cognitive-emotion regulation, and decision making to see if there were correlations with successful SWAT callout resolution. These findings would then be compared with the results of a national survey of hostage (crisis) negotiators in the hopes of finding information that might be helpful with team dynamics, officer selection for these teams, and with operational dynamics and successful resolution of SWAT callouts. Design/methodology/approach Active SWAT officers (n=277) from various law enforcement entities in 21 states participated in this survey research. They completed a demographic questionnaire, questions about their callout experiences and experiences on their SWAT team, the Big 5 Personality Inventory, the Cognitive-Emotion Regulation Questionnaire, and the General Decision-Making Style questionnaire. These results were then compared with the same results obtained from a national survey of hostage (crisis) negotiators (n=514) and patrol officers (n=72). Findings Common personality and decision-making styles emerged from the SWAT survey, and correlations between these variables and the successful resolution of SWAT callouts are discussed. These results were then compared with negotiators and patrol officers via an ANOVA. Distinct differences between these groups emerged. Research limitations/implications Recruiting research participants from law enforcement, much less from a closed group such as SWAT operators, is difficult. The response rate for this study was low, and was due in part to the agency themselves declining to participate. The current study relied on honest self-report, which is always a limitation of this type of survey research. Another limitation was that lack of statistically significant findings for the multivariate and the binomial logistic regression analysis. No extrapolation of the relationship between personality, cognitive-emotion regulation, and decision-making styles and the outcome and resolution of callouts is possible based on these findings. Practical implications This research could have direct effect on the training and selection of SWAT team officers and hostage negotiators. There is also information provided that may impact the operation and coordination of these groups as they work together during callouts in the community. Social implications The current social climate in the USA seems to be calling for police departments to do everything possible to resolve high risk and dangerous situations with as much care and as little force as possible. In order to achieve successful and peaceful resolution of these SWAT callout situations, departments must deploy officers with the necessary skills, personality, and decision-making abilities. Originality/value There is very little general research on SWAT teams, and almost nothing on SWAT operator experience, personality, or decision making. These findings have value and application in SWAT operator selection and training, along with SWAT and negotiator dynamics and decision making when trying to successfully and peacefully resolve a SWAT callout operation.
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Laux, Lori, Karen Dysert, Sharon Kiely, and Jeff Weimerskirch. "Trauma VAP SWAT Team." Critical Care Nursing Quarterly 33, no. 2 (April 2010): 126–31. http://dx.doi.org/10.1097/cnq.0b013e3181d911bb.
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Revesman, Mark E., and Stephen M. Rokicki. "Assessment of SWAT Accuracy." Proceedings of the Human Factors Society Annual Meeting 29, no. 2 (October 1985): 183–87. http://dx.doi.org/10.1177/154193128502900220.
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Yamini Priya, R., and R. Manjula. "A review for comparing SWAT and SWAT coupled models and its applications." Materials Today: Proceedings 45 (2021): 7190–94. http://dx.doi.org/10.1016/j.matpr.2021.02.414.
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Zhang, Dejian, Xingwei Chen, and Huaxia Yao. "SWAT-CS enm : Enhancing SWAT nitrate module for a Canadian Shield catchment." Science of The Total Environment 550 (April 2016): 598–610. http://dx.doi.org/10.1016/j.scitotenv.2016.01.109.
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Mann, B. S., J. R. Johnson, K. He, R. Sridhara, A. T. Farrell, R. Dagher, R. Justice, and R. Pazdur. "Utility of photography to confirm skin lesion response assessed using a severity weighted assessment tool (SWAT) in cutaneous T-cell lymphoma (CTCL)." Journal of Clinical Oncology 25, no. 18_suppl (June 20, 2007): 6579. http://dx.doi.org/10.1200/jco.2007.25.18_suppl.6579.
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6579 Background: In Oct 2006, FDA approved vorinostat for treatment of cutaneous manifestations of CTCL–based on response rate and duration of response observed in CTCL skin lesions. Response was determined by change in SWAT score at follow up compared to the baseline score. SWAT Score: sum of % Body Surface Area weighted by factor 1, 2, or 4 for patch (no elevation from normal skin), plaque (< 5 mm elevation) and tumor (= 5 mm elevation), respectively. All responses but one were partial. A partial response required = 50% reduction in whole body SWAT score lasting = 4 weeks. FDA also reviewed serial photographs of all patients (standard whole body views and close-ups of skin lesions), submitted as supportive evidence. Methods: An expert external reviewer, blind to SWAT scores, adjudicated responses by examining photographs and response determinations by photographs and by SWAT scores were compared. Results: Based on SWAT scores, skin lesions in 18 of 61 stage = IIB CTCL patients responded to vorinostat; there were 17 partial and 1 complete responses. Blinded reviewer adjudicated 4 photographs not evaluable (reasons: blurred image, color or light problem, wrong label), easily confirmed 7 responses, and called 7 responses equivocal. Responses seemed easier to determine in skin lesions with tumors or ulcers. Predominantly patch or plaque lesions were harder to evaluate: patches due to poor color reproduction and plaques due to inability to palpate. A response from plaque to patch morphology decreases SWAT score 50%, but the change may not manifest adequately in a photograph. Small sample size did not allow a reliable statistical analysis for correlation between different lesion types and ability to confirm objective responses (based on SWAT scores) by photography. Conclusions: Photography allows a limited evaluation of skin lesions in CTCL: inability to measure lesion thickness in photographs limits direct confirmation of SWAT scores. Photography complements SWAT evaluation: in half the cases in the vorinostat pivotal trial, a response by SWAT score was easily confirmed by the reviewer blind to SWAT scores. Further experience and technological advances in photography may reduce the number of not evaluable photographs. No significant financial relationships to disclose.
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Bailey, Ryan T., Katrin Bieger, Jeffrey G. Arnold, and David D. Bosch. "A New Physically-Based Spatially-Distributed Groundwater Flow Module for SWAT+." Hydrology 7, no. 4 (October 9, 2020): 75. http://dx.doi.org/10.3390/hydrology7040075.
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Watershed models are used worldwide to assist with water and nutrient management under conditions of changing climate, land use, and population. Of these models, the Soil and Water Assessment Tool (SWAT) and SWAT+ are the most widely used, although their performance in groundwater-driven watersheds can sometimes be poor due to a simplistic representation of groundwater processes. The purpose of this paper is to introduce a new physically-based spatially-distributed groundwater flow module called gwflow for the SWAT+ watershed model. The module is embedded in the SWAT+ modeling code and is intended to replace the current SWAT+ aquifer module. The model accounts for recharge from SWAT+ Hydrologic Response Units (HRUs), lateral flow within the aquifer, Evapotranspiration (ET) from shallow groundwater, groundwater pumping, groundwater–surface water interactions through the streambed, and saturation excess flow. Groundwater head and groundwater storage are solved throughout the watershed domain using a water balance equation for each grid cell. The modified SWAT+ modeling code is applied to the Little River Experimental Watershed (LREW) (327 km2) in southern Georgia, USA for demonstration purposes. Using the gwflow module for the LREW increased run-time by 20% compared to the original SWAT+ modeling code. Results from an uncalibrated model are compared against streamflow discharge and groundwater head time series. Although further calibration is required if the LREW model is to be used for scenario analysis, results highlight the capabilities of the new SWAT+ code to simulate both land surface and subsurface hydrological processes and represent the watershed-wide water balance. Using the modified SWAT+ model can provide physically realistic groundwater flow gradients, fluxes, and interactions with streams for modeling studies that assess water supply and conservation practices. This paper also serves as a tutorial on modeling groundwater flow for general watershed modelers.
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Bateman, Vesta I., Randall L. Mayes, and Thomas G. Carne. "Comparison of Force Reconstruction Methods for a Lumped Mass Beam." Shock and Vibration 4, no. 4 (1997): 231–39. http://dx.doi.org/10.1155/1997/642780.
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Two extensions of the force reconstruction method, the sum of weighted accelerations technique (SWAT), are presented in this article. SWAT requires the use of the structure’s elastic mode shapes for reconstruction of the applied force. Although based on the same theory, the two new techniques do not rely on mode shapes to reconstruct the applied force and may be applied to structures whose mode shapes are not available. One technique uses the measured force and acceleration responses with the rigid body mode shapes to calculate the scalar weighting vector, so the technique is called SWAT-CAL (SWAT using a calibrated force input). The second technique uses the free-decay time response of the structure with the rigid body mode shapes to calculate the scalar weighting vector and is called SWAT-TEEM (SWAT using time eliminated elastic modes). All three methods are used to reconstruct forces for a simple structure.
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Li, Dachen, Simin Qu, Peng Shi, Xueqiu Chen, Feng Xue, Jianfeng Gou, and Wenhao Zhang. "Development and Integration of Sub-Daily Flood Modelling Capability within the SWAT Model and a Comparison with XAJ Model." Water 10, no. 9 (September 15, 2018): 1263. http://dx.doi.org/10.3390/w10091263.
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To date, floods have become one of the most severe natural disasters on Earth. Flood forecasting with hydrological models is an important non-engineering measure for flood control and disaster reduction. The Xin’anjiang (XAJ) model is the most widely used hydrological model in China for flood forecasting, while the Soil and Water Assessment Tool (SWAT) model is widely applied for daily and monthly simulation and has shown its potential for flood simulation. The objective of this paper is to evaluate the performance of the SWAT model in simulating floods at a sub-daily time-scale in a slightly larger basin and compare that with the XAJ model. Taking Qilijie Basin (southeast of China) as a study area, this paper developed the XAJ model and SWAT model at a sub-daily time-scale. The results showed that the XAJ model had a better performance than the sub-daily SWAT model regarding relative runoff error (RRE) but the SWAT model performed well according to relative peak discharge error (RPE) and error of occurrence time of peak flow (PTE). The SWAT model performed unsatisfactorily in simulating low flows due to the daily calculation of base flow but behaved quite well in simulating high flows. We also evaluated the effect of spatial scale on the SWAT model. The results showed that the SWAT model had a good applicability at different spatial scales. In conclusion, the sub-daily SWAT model is a promising tool for flood simulation though more improvements remain to be studied further.
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Kim, Dongho, Jiwon Lee, Hyemin Jeong, Yongsung Kwon, Byeongwon Lee, and Sangchul Lee. "Application and evaluation of SWAT-C model to predict TOC loading in the Hwangryong River Watershed." Journal of Korean Society of Environmental Engineers 44, no. 10 (October 31, 2022): 354–65. http://dx.doi.org/10.4491/ksee.2022.44.10.354.
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Objectives : This study aims to assess the applicability of the SWAT-C water quality model recently developed to predict in-stream Total Organic Carbon (TOC) in a watershed within South Korea.Methods : The SWAT-C model was tested in the Hwangryong River Watershed. SWAT-C is an advanced version of Soil and Water Assessment Tool (SWAT) to simulate carbon cycling at the watershed scale. The model was simulated for 11 years (2010-2020) consisting of 2-year warm-up (2010-2011), 6-year calibration (2012-2017), and 3-year validation (2018-2020) periods. SWAT-C was calibrated and validated against monthly streamflow and TOC loads. The model performance was evaluated using NSE (Nash-Sutcliffe efficiency), KGE (Kling-Gupta efficiency), and PBIAS (percent bias) Simulated Dissolve Organic Carbon (DOC) and Particulate Organic Carbon (POC) loads were also presented to see the major caron type loaded to the downstream.Results and Discussion : The calibration results showed that SWAT-C could depict streamflow and TOC loads with acceptance model performances (NSE > 0.5, KGE > 0.5 and PBIAS =< 25%). Especially, the seasonal variations of TOC loads were well simulated by SWAT-C. The TOC load was predicted to increase in the summer season with high precipitation and slightly lower in the other seasons. This seasonal pattern is likely caused by frequent heavy rainfall events in summer.Conclusion : This study demonstrated that SWAT-C model is applicable in South Korea with sufficient prediction accuracy. Thus, SWAT-C would serve as an efficient tool to monitor TOC loads in South Korea.
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Kumar, Eeshan, Dharmendra Saraswat, and Gurdeep Singh. "Comparative Analysis of Bioenergy Crop Impacts on Water Quality Using Static and Dynamic Land Use Change Modeling Approach." Water 12, no. 2 (February 4, 2020): 410. http://dx.doi.org/10.3390/w12020410.
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Researchers and federal and state agency officials have long been interested in evaluating location-specific impact of bioenergy energy crops on water quality for developing policy interventions. This modeling study examines long-term impact of giant miscanthus and switchgrass on water quality in the Cache River Watershed (CRW) in Arkansas, United States. The bioenergy crops were simulated on marginal lands using two variants of a Soil and Watershed Assessment Tool (SWAT) model. The first SWAT variant was developed using a static (single) land-use layer (regular-SWAT) and for the second, a dynamic land-use change feature was used with multiple land use layers (location-SWAT). Results indicated that the regular-SWAT predicted larger losses for sediment, total phosphorus and total nitrogen when compared to location-SWAT at the watershed outlet. The lower predicted losses from location-SWAT were attributed to its ability to vary marginal land area between 3% and 11% during the 20-year modeling period as opposed to the regular-SWAT that used a fixed percentage of marginal land area (8%) throughout the same period. Overall, this study demonstrates that environmental impacts of bioenergy crops were better assessed using the dynamic land-use representation approach, which would eliminate any unintended prediction bias in the model due to the use of a single land use layer.
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Zhang, Limin, Xianyong Meng, Hao Wang, Mingxiang Yang, and Siyu Cai. "Investigate the Applicability of CMADS and CFSR Reanalysis in Northeast China." Water 12, no. 4 (April 1, 2020): 996. http://dx.doi.org/10.3390/w12040996.
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Reanalysis datasets can provide alternative and complementary meteorological data sources for hydrological studies or other scientific studies in regions with few gauge stations. This study evaluated the accuracy of two reanalysis datasets, the China Meteorological Assimilation Driving Datasets for the Soil and Water Assessment Tool (SWAT) model (CMADS) and Climate Forecast System Reanalysis (CFSR), against gauge observations (OBS) by using interpolation software and statistical indicators in Northeast China (NEC), as well as their annual average spatial and monthly average distributions. The reliability and applicability of the two reanalysis datasets were assessed as inputs in a hydrological model (SWAT) for runoff simulation in the Hunhe River Basin. Statistical results reveal that CMADS performed better than CFSR for precipitation and temperature in NEC with the indicators closer to optimal values (the ratio of standard deviations of precipitation and maximum/minimum temperature from CMADS were 0.92, 1.01, and 0.995, respectively, while that from CFSR were 0.79, 1.07, and 0.897, respectively). Hydrological modelling results showed that CMADS + SWAT and OBS + SWAT performed far better than CFSR + SWAT on runoff simulations. The Nash‒Sutcliffe efficiency (NSE) of CMADS + SWAT and OBS + SWAT ranged from 0.54 to 0.95, while that of CFSR + SWAT ranged from −0.07 to 0.85, exhibiting poor performance. The CMADS reanalysis dataset is more accurate than CFSR in NEC and is a suitable input for hydrological simulations.
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Koycegiz, Cihangir, and Meral Buyukyildiz. "Calibration of SWAT and Two Data-Driven Models for a Data-Scarce Mountainous Headwater in Semi-Arid Konya Closed Basin." Water 11, no. 1 (January 16, 2019): 147. http://dx.doi.org/10.3390/w11010147.
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Hydrologic models are important tools for the successful management of water resources. In this study, a semi-distributed soil and water assessment tool (SWAT) model is used to simulate streamflow at the headwater of Çarşamba River, located at the Konya Closed Basin, Turkey. For that, first a sequential uncertainty fitting-2 (SUFI-2) algorithm is employed to calibrate the SWAT model. The SWAT model results are also compared with the results of the radial-based neural network (RBNN) and support vector machines (SVM). The SWAT model performed well at the calibration stage i.e., determination coefficient (R2) = 0.787 and Nash–Sutcliffe efficiency coefficient (NSE) = 0.779, and relatively lower values at the validation stage i.e., R2 = 0.508 and NSE = 0.502. Besides, the data-driven models were more successful than the SWAT model. Obviously, the physically-based SWAT model offers significant advantages such as performing a spatial analysis of the results, creating a streamflow model taking into account the environmental impacts. Also, we show that SWAT offers the ability to produce consistent solutions under varying scenarios whereas it requires a large number of inputs as compared to the data-driven models.
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Rahmat Rizalmi, Sigit, and Indah Wahyu Utami. "Analisis Beban Kerja Kognitif Dengan Menggunakan Metode Subjective Workload Assessment Technique (SWAT) Pada Karyawan Departemen Quality Control Di PT. XYZ." Journal Science Innovation and Technology (SINTECH) 1, no. 01 (November 14, 2020): 30–35. http://dx.doi.org/10.47701/sintech.v1i01.875.
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Beban kerja merupakan upaya yang dikeluarkan individu dalam memberikan performa untukmelakukan suatu aktivitas. Beban kerja dalam kajian ergonomi terbagi menjadi beban kerja fisikdan beban kerja kognitif. Penelitian ini bertujuan untuk mengukur beban kerja kognitif karyawandepartemen quality control di PT. XYZ. Subjek penelitian ini berjumlah 17 karyawan departemenquality control dan menggunakan metode Subjective workload assessment technique (SWAT).Metode SWAT menggunakan tiga variabel yaitu Time Load, Mental Effort Load danPsychological Stress Load. Tahapan SWAT terdiri dari 2 tahapan yaitu : Scale Development danEvent Scoring. Hasil penelitian dengan menggunakan metode SWAT menunjukan variabelPsychological Stress Load dominan mempengaruhi beban kerja karyawan (45,40%), artinyafaktor motivasi, kelelahan, rasa takut, dan tingkat keahlian, dan lingkungan mempengaruhi bebankerja kognitif karyawan departemen quality control.
Kata Kunci : Beban Kerja Kognitif, Scale Development, Event Scoring, SWAT
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Alemayehu, Tadesse, Ann van Griensven, Befekadu Taddesse Woldegiorgis, and Willy Bauwens. "An improved SWAT vegetation growth module and its evaluation for four tropical ecosystems." Hydrology and Earth System Sciences 21, no. 9 (September 7, 2017): 4449–67. http://dx.doi.org/10.5194/hess-21-4449-2017.
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Abstract. The Soil and Water Assessment Tool (SWAT) is a globally applied river basin ecohydrological model used in a wide spectrum of studies, ranging from land use change and climate change impacts studies to research for the development of the best water management practices. However, SWAT has limitations in simulating the seasonal growth cycles for trees and perennial vegetation in the tropics, where rainfall rather than temperature is the dominant plant growth controlling factor. Our goal is to improve the vegetation growth module of SWAT for simulating the vegetation variables – such as the leaf area index (LAI) – for tropical ecosystems. Therefore, we present a modified SWAT version for the tropics (SWAT-T) that uses a straightforward but robust soil moisture index (SMI) – a quotient of rainfall (P) and reference evapotranspiration (ETr) – to dynamically initiate a new growth cycle within a predefined period. Our results for the Mara Basin (Kenya/Tanzania) show that the SWAT-T-simulated LAI corresponds well with the Moderate Resolution Imaging Spectroradiometer (MODIS) LAI for evergreen forest, savanna grassland and shrubland. This indicates that the SMI is reliable for triggering a new annual growth cycle. The water balance components (evapotranspiration and streamflow) simulated by the SWAT-T exhibit a good agreement with remote-sensing-based evapotranspiration (ET-RS) and observed streamflow. The SWAT-T model, with the proposed vegetation growth module for tropical ecosystems, can be a robust tool for simulating the vegetation growth dynamics in hydrologic models in tropical regions.
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Tan, Mou Leong, Philip W. Gassman, Raghavan Srinivasan, Jeffrey G. Arnold, and XiaoYing Yang. "A Review of SWAT Studies in Southeast Asia: Applications, Challenges and Future Directions." Water 11, no. 5 (May 1, 2019): 914. http://dx.doi.org/10.3390/w11050914.
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The Soil and Water Assessment Tool (SWAT) model is recognized as one of the top hydrological models applied for addressing hydrologic and environmental issues. This is the first review on the SWAT model studies in Southeast Asia, with an emphasis on its applications, current challenges and future research directions. A total of 126 articles were identified since 2006; roughly 50% of these studies were conducted in Vietnam or Thailand. About 16% of the studies were performed at a transnational scale, which included Cambodia, Lao PDR, Thailand, and Vietnam. Model capability assessment, land use, and climate change assessment are the main SWAT applications that have been reported for the region. Most of the SWAT calibration and validation results for these studies were classified as satisfactory to very good results based on widely recognized performance indicators. However, the parameterization, calibration and validation procedures are not well reported in some articles. Availability of reliable data is one of the main problems that SWAT users are confronted with, as these data are either not freely available or restricted from public access in some countries. Hence, future studies should be considered on identification and development of reliable input data for SWAT modeling. SWAT model modification based on the SEA climate, geographical and land use conditions is another research direction to be considered in the future. Moreover, application of SWAT for extreme events simulation requires more attention in this region.