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Civil and Environmental Engineering and Construction Faculty Research
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Articles 1 - 20 of 20
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An Analysis Of Energy Consumption And The Use Of Renewables For A Small Drinking Water Treatment Plant, Saria Bukhary, Jacimara Batista, Sajjad Ahmad
An Analysis Of Energy Consumption And The Use Of Renewables For A Small Drinking Water Treatment Plant, Saria Bukhary, Jacimara Batista, Sajjad Ahmad
Civil and Environmental Engineering and Construction Faculty Research
One of the pressing issues currently faced by the water industry is incorporating sustainability considerations into design practice and reducing the carbon emissions of energy-intensive processes. Water treatment, an indispensable step for safeguarding public health, is an energy-intensive process. The purpose of this study was to analyze the energy consumption of an existing drinking water treatment plant (DWTP), then conduct a modeling study for using photovoltaics (PVs) to offset that energy consumption, and thus reduce emissions. The selected plant, located in southwestern United States, treats 0.425 m3 of groundwater per second by utilizing the processes of coagulation, filtration, and disinfection. …
Bringing Statistical Learning Machines Together For Hydro-Climatological Predictions - Case Study For Sacramento San Joaquin River Basin, California, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad, Kenneth W. Lamb, Venkat Lakshmi
Bringing Statistical Learning Machines Together For Hydro-Climatological Predictions - Case Study For Sacramento San Joaquin River Basin, California, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad, Kenneth W. Lamb, Venkat Lakshmi
Civil and Environmental Engineering and Construction Faculty Research
Study region: Sacramento San Joaquin River Basin, California Study focus: The study forecasts the streamflow at a regional scale within SSJ river basin with largescale climate variables. The proposed approach eliminates the bias resulting from predefined indices at regional scale. The study was performed for eight unimpaired streamflow stations from 1962–2016. First, the Singular Valued Decomposition (SVD) teleconnections of the streamflow corresponding to 500 mbar geopotential height, sea surface temperature, 500 mbar specific humidity (SHUM500), and 500 mbar U-wind (U500) were obtained. Second, the skillful SVD teleconnections were screened non-parametrically. Finally, the screened teleconnections were used as the streamflow predictors …
Phytoplankton Community And Algal Toxicity At A Recurring Bloom In Sullivan Bay, Kabetogama Lake, Minnesota, Usa, Victoria G. Christensen, Ryan P. Maki, Erin A. Stelzer, Jack E. Norlan, Eakalak Khan
Phytoplankton Community And Algal Toxicity At A Recurring Bloom In Sullivan Bay, Kabetogama Lake, Minnesota, Usa, Victoria G. Christensen, Ryan P. Maki, Erin A. Stelzer, Jack E. Norlan, Eakalak Khan
Civil and Environmental Engineering and Construction Faculty Research
Kabetogama Lake in Voyageurs National Park, Minnesota, USA suffers from recurring late summer algal blooms that often contain toxin-producing cyanobacteria. Previous research identified the toxin microcystin in blooms, but we wanted to better understand how the algal and cyanobacterial community changed throughout an open water season and how changes in community structure were related to toxin production. Therefore, we sampled one recurring bloom location throughout the entire open water season. The uniqueness of this study is the absence of urban and agricultural nutrient sources, the remote location, and the collection of samples before any visible blooms were present. Through quantitative …
A Dynamic Quantitative Microbial Risk Assessment For Norovirus In Potable Reuse System, Erfaneh Amoueyan, Sajjad Ahmad, Joseph N.S. Eisenberg, Daniel Gerrity
A Dynamic Quantitative Microbial Risk Assessment For Norovirus In Potable Reuse System, Erfaneh Amoueyan, Sajjad Ahmad, Joseph N.S. Eisenberg, Daniel Gerrity
Civil and Environmental Engineering and Construction Faculty Research
This study describes the results of a dynamic quantitative microbial risk assessment (QMRA) for norovirus (NoV) that was used to evaluate the relative significance of foodborne, person-to-person, and person-to-sewage-to-person transmission pathways. This last pathway was incorporated into simulated potable reuse systems to evaluate the adequacy of typical treatment trains, operational conditions, and regulatory frameworks. The results confirm that secondary and foodborne transmission dominate the overall risk calculation and that waterborne NoV likely contributes no appreciable public health risk, at least in the scenarios modeled in this study. De facto reuse with an environmental buffer storage time of at least 30 …
Melpf Version 1: Modeling Error Learning Based Post-Processor Framework For Hydrologic Models Accuracy Improvement, Rui Wu, Lei Yang, Chao Chen, Sajjad Ahmad, Sergiu M. Dascalu, Frederick C. Harris Jr.
Melpf Version 1: Modeling Error Learning Based Post-Processor Framework For Hydrologic Models Accuracy Improvement, Rui Wu, Lei Yang, Chao Chen, Sajjad Ahmad, Sergiu M. Dascalu, Frederick C. Harris Jr.
Civil and Environmental Engineering and Construction Faculty Research
This paper studies how to improve the accuracy of hydrologic models using machine-learning models as post-processors and presents possibilities to reduce the workload to create an accurate hydrologic model by removing the calibration step. It is often challenging to develop an accurate hydrologic model due to the time-consuming model calibration procedure and the nonstationarity of hydrologic data. Our findings show that the errors of hydrologic models are correlated with model inputs. Thus motivated, we propose a modeling-error-learning-based post-processor framework by leveraging this correlation to improve the accuracy of a hydrologic model. The key idea is to predict the differences (errors) …
Rheological Properties Of Modified Crumb Rubber Asphalt Binder And Selecting The Best Modified Binder Using Ahp Method, Mehdi Khalili, Kazem Jadidi, Serji Amirkhanian
Rheological Properties Of Modified Crumb Rubber Asphalt Binder And Selecting The Best Modified Binder Using Ahp Method, Mehdi Khalili, Kazem Jadidi, Serji Amirkhanian
Civil and Environmental Engineering and Construction Faculty Research
Crumb rubber modifier (CRM) is one of the most popular asphalt binder modifiers due to the economic benefits and desired physical and rheological properties of asphalt binders and asphalt mixes. This research focuses on evaluating the properties of rubber-modified asphalt binders and selecting the best modified binder. The modified binders were produced by blending virgin binders with CRM at various contents of different gradations, and different methods of grinding. CRM made through ambient and cryogenic grinding methods with two gradation sizes were produced and tested. Three different virgin binders from two sources were obtained and used. The Analytic Hierarchy Process …
Bulbous Pier: An Alternative To Bridge Pier Extension As A Countermeasure Against Bridge Deck Splashing, Moses Karakouzian, Amilcar Chavez, Donald Hayes, Mohammad Nazari-Sharabian
Bulbous Pier: An Alternative To Bridge Pier Extension As A Countermeasure Against Bridge Deck Splashing, Moses Karakouzian, Amilcar Chavez, Donald Hayes, Mohammad Nazari-Sharabian
Civil and Environmental Engineering and Construction Faculty Research
Bridge deck splashing causes deterioration to a bridge’s structure and renders the bridge unsafe for motorists and pedestrians. The traditional countermeasure for bridge deck splashing has been pier extension. Pier extensions move the pier wave and the associated splash away from the bridge deck, but retrofitting existing bridges with pier extensions is costly. This research evaluates the use of a bulbous added to the pier as an alternative to pier extension. A bulb placed on the upstream side of a bridge pier affects the splashing. The energy in the passing water is redirected from the impact by streamlining the flow. …
Development Of Threshold Levels And A Climate-Sensitivity Model Of The Hydrological Regime Of The High-Altitude Catchment Of The Western Himalayas, Pakistan, Muhammad Saifullah, Shiyin Liu, Adnan Ahmad Tahir, Muhammad Zaman, Sajjad Ahmad, Muhammad Adnan, Dianyu Chen, Muhammad Ashraf, Asif Mehmood
Development Of Threshold Levels And A Climate-Sensitivity Model Of The Hydrological Regime Of The High-Altitude Catchment Of The Western Himalayas, Pakistan, Muhammad Saifullah, Shiyin Liu, Adnan Ahmad Tahir, Muhammad Zaman, Sajjad Ahmad, Muhammad Adnan, Dianyu Chen, Muhammad Ashraf, Asif Mehmood
Civil and Environmental Engineering and Construction Faculty Research
Water shortages in Pakistan are among the most severe in the world, and its water resources are decreasing significantly due to the prevailing hydro-meteorological conditions. We assessed variations in meteorological and hydrological variables using innovative trend analysis (ITA) and traditional trend analysis methods at a practical significance level, which is also of practical interest. We developed threshold levels of hydrological variables and developed a non-parametric climate-sensitivity model of the high-altitude catchment of the western Himalayas. The runoff of Zone I decreased, while the temperature increased and the precipitation increased significantly. In Zone II, the runoff and temperature increased but the …
Effect Of Overburden Height On Hydraulic Fracturing Of Concrete-Lined Pressure Tunnels Excavated In Intact Rock: A Numerical Study, Moses Karakouzian, Mohammad Nazari-Sharabian, Mehrdad Karami
Effect Of Overburden Height On Hydraulic Fracturing Of Concrete-Lined Pressure Tunnels Excavated In Intact Rock: A Numerical Study, Moses Karakouzian, Mohammad Nazari-Sharabian, Mehrdad Karami
Civil and Environmental Engineering and Construction Faculty Research
: This study investigated the impact of overburden height on the hydraulic fracturing of a concrete-lined pressure tunnel, excavated in intact rock, under steady-state and transient-state conditions. Moreover, the Norwegian design criterion that only suggests increasing the overburden height as a countermeasure against hydraulic fracturing was evaluated. The Mohr–Coulomb failure criterion was implemented to investigate failure in the rock elements adjacent to the lining. A pressure tunnel with an inner diameter of 3.6 m was modeled in Abaqus Finite Element Analysis (FEA), using the finite element method (FEM). It was assumed that transient pressures occur inside the tunnel due to …
Investigation Of Tactile Sensory System Configuration For Construction Hazard Perception, Sayan Sakhakarmi, Jeewoong Park
Investigation Of Tactile Sensory System Configuration For Construction Hazard Perception, Sayan Sakhakarmi, Jeewoong Park
Civil and Environmental Engineering and Construction Faculty Research
The application of tactile-based wearable devices to assist in navigation for people with low sight/low memory has demonstrated the feasibility of using such devices as a means of communication. Accordingly, a previous study in construction research investigated various parameters of tactile signals to develop a communicable system for potential application in construction hazard communication. However, the nature of construction limits the application of such devices to the body of construction workers, and it is important to understand sensor design parameters for improved communication, which has not been given significant attention yet. Therefore, this study aims to determine key design factors …
Optimization Of Photocatalytic Degradation Of Acid Blue 113 And Acid Red 88 Textile Dyes In A Uv-C/Tio2 Suspension System: Application Of Response Surface Methodology (Rsm), Ali Saber, David E. James, Soroosh Mortazavian
Optimization Of Photocatalytic Degradation Of Acid Blue 113 And Acid Red 88 Textile Dyes In A Uv-C/Tio2 Suspension System: Application Of Response Surface Methodology (Rsm), Ali Saber, David E. James, Soroosh Mortazavian
Civil and Environmental Engineering and Construction Faculty Research
Textile industries produce copious amounts of colored wastewater some of which are toxic to humans and aquatic biota. This study investigates optimization of a bench-scale UV-C photocatalytic process using a TiO2 catalyst suspension for degradation of two textile dyes, Acid Blue 113 (AB 113) and Acid Red 88 (AR 88). From preliminary experiments, appropriate ranges for experimental factors including reaction time, solution pH, initial dye concentration and catalyst dose, were determined for each dye. Response surface methodology (RSM) using a cubic IV optimal design was then used to design the experiments and optimize the process. Analysis of variance (ANOVA) was …
Changes In Snow Phenology From 1979 To 2016 Over The Tianshan Mountains, Central Asia, Tao Yang, Qian Li, Sajjad Ahmad, Hongfei Zhou, Lanhai Li
Changes In Snow Phenology From 1979 To 2016 Over The Tianshan Mountains, Central Asia, Tao Yang, Qian Li, Sajjad Ahmad, Hongfei Zhou, Lanhai Li
Civil and Environmental Engineering and Construction Faculty Research
Snowmelt from the Tianshan Mountains (TS) is a major contributor to the water resources of the Central Asian region. Thus, changes in snow phenology over the TS have significant implications for regional water supplies and ecosystem services. However, the characteristics of changes in snow phenology and their influences on the climate are poorly understood throughout the entire TS due to the lack of in situ observations, limitations of optical remote sensing due to clouds, and decentralized political landscapes. Using passive microwave remote sensing snow data from 1979 to 2016 across the TS, this study investigates the spatiotemporal variations of snow …
Water Quality Modeling Of Mahabad Dam Watershed–Reservoir System Under Climate Change Conditions, Using Swat And System Dynamics, Mohammad Nazari-Sharabian, Masoud Taheriyoun, Sajjad Ahmad, Moses Karakouzian, Azadeh Ahmadi
Water Quality Modeling Of Mahabad Dam Watershed–Reservoir System Under Climate Change Conditions, Using Swat And System Dynamics, Mohammad Nazari-Sharabian, Masoud Taheriyoun, Sajjad Ahmad, Moses Karakouzian, Azadeh Ahmadi
Civil and Environmental Engineering and Construction Faculty Research
The total phosphorus (TP) concentration, as the primary limiting eutrophication factor in the Mahabad Dam reservoir in Iran, was studied, considering the combined impacts of climate change, as well as the scenarios on changes in upstream TP loadings and downstream dam water allocations. Downscaled daily projected climate data were obtained from the Beijing Normal University Earth System Model (BNU-ESM) under moderate (RCP4.5) and extreme (RCP8.5) scenarios. These data were used as inputs of a calibrated Soil and Water Assessment Tool (SWAT) model of the watershed in order to determine the effects of climate change on runoff yields in the watershed …
Flow-Induced Stresses And Displacements In Jointed Concrete Pipes Installed By Pipe Jacking Method, Moses Karakouzian, Mehrdad Karami, Mohammad Nazari-Sharabian, Sajjad Ahmad
Flow-Induced Stresses And Displacements In Jointed Concrete Pipes Installed By Pipe Jacking Method, Moses Karakouzian, Mehrdad Karami, Mohammad Nazari-Sharabian, Sajjad Ahmad
Civil and Environmental Engineering and Construction Faculty Research
Transient flows result in unbalanced forces and high pressure in pipelines. Under these conditions, the combined effects of flow-induced forces along with sudden pipe displacements can create cracks in the pipeline, especially at the junctions. This situation consequently results in water leakage and reduced operational efficiency of the pipeline. In this study, displacements and stresses in a buried pressurized water transmission pipe installed by pipe jacking method are investigated using numerical modeling and considering interactions between fluid, pipe, and soil. The analyses were performed consecutively under no-flow, steady flow, and transient flow conditions, in order to investigate the effects of …
Modeling Of Grace-Derived Groundwater Information In The Colorado River Basin, Md Mafuzur Rahaman, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad
Modeling Of Grace-Derived Groundwater Information In The Colorado River Basin, Md Mafuzur Rahaman, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad
Civil and Environmental Engineering and Construction Faculty Research
Groundwater depletion has been one of the major challenges in recent years. Analysis of groundwater levels can be beneficial for groundwater management. The National Aeronautics and Space Administration’s twin satellite, Gravity Recovery and Climate Experiment (GRACE), serves in monitoring terrestrial water storage. Increasing freshwater demand amidst recent drought (2000–2014) posed a significant groundwater level decline within the Colorado River Basin (CRB). In the current study, a non-parametric technique was utilized to analyze historical groundwater variability. Additionally, a stochastic Autoregressive Integrated Moving Average (ARIMA) model was developed and tested to forecast the GRACE-derived groundwater anomalies within the CRB. The ARIMA model …
Identification Of Critical Source Areas (Csas) And Evaluation Of Best Management Practices (Bmps) In Controlling Eutrophication In The Dez River Basin, Hadi Babaei, Mohammad Nazari-Sharabian, Moses Karakouzian, Sajjad Ahmad
Identification Of Critical Source Areas (Csas) And Evaluation Of Best Management Practices (Bmps) In Controlling Eutrophication In The Dez River Basin, Hadi Babaei, Mohammad Nazari-Sharabian, Moses Karakouzian, Sajjad Ahmad
Civil and Environmental Engineering and Construction Faculty Research
Best Management Practices (BMPs) are commonly used to control pollution in the river basins. Prioritization of BMPs helps improve the efficiency and effectiveness of pollution reduction, especially in Critical Source Areas (CSAs) that produce the highest pollution loads. Recently, the Dez River in Khuzestan, Iran, has become highly eutrophic from the overuse of fertilizers and pesticides. In this basin, dry and irrigated farming produce 77.34% and 6.3% of the Total Nitrogen (TN) load, and 83.56% and 4.3% of the Total Phosphorus (TP) load, respectively. In addition, residential, pasture, and forest land uses together account for 16.36% of the TN and …
Gis Framework For Spatiotemporal Mapping Of Urban Flooding, Sayed Joinal Hossain Abedin, Haroon Stephen
Gis Framework For Spatiotemporal Mapping Of Urban Flooding, Sayed Joinal Hossain Abedin, Haroon Stephen
Civil and Environmental Engineering and Construction Faculty Research
This research aims to develop a framework using the Geographic Information System (GIS) to perform modeling and mapping of flood spatiotemporal variation in urban micro-watersheds. The GIS-framework includes a workflow of several methods and processes including delineation of urban watershed, generation of runoff hydrographs, and time series mapping of inundation depths and flood extent. This framework is tested in areas previously known to have experienced flooding at the University of Nevada, Las Vegas main campus, including Black Parking Lot (Blacklot) and East Mall. Calibration is performed by varying Digital Elevation Model (DEM) resolution, rainfall temporal resolution, and clogging factor whereas …
Toughness, Tenacity And Maximum Initial Strength Of Rubber Modified Asphalt Binders, Kazem Jadidi, Mehdi Khalili, Moses Karakouzian, Serji Amirkhanian
Toughness, Tenacity And Maximum Initial Strength Of Rubber Modified Asphalt Binders, Kazem Jadidi, Mehdi Khalili, Moses Karakouzian, Serji Amirkhanian
Civil and Environmental Engineering and Construction Faculty Research
The toughness and tenacity test method, which was developed in the 1980s, is popular for evaluating a polymermodified binder. Several states like Nevada require performing this test to evaluate non-modified binder samples, as well as other types of modified binders. In this regard, a toughness and tenacity test was performed on rubber-modified samples produced from virgin binder PG58-28, PG64-16 and AC-20. In order to take the rubber size, type and content into account, two rubber sizes, mesh #20 and #40, two rubber types, ambient and cryogenic, and three rubber contents, 10%, 15%, and 20% were produced and tested. The results …
Effects Of Enso On Temperature, Precipitation, And Potential Evapotranspiration Of North India’S Monsoon: An Analysis Of Trend And Entropy, Kazi Tamaddun, Ajay Kalra, Miguel Bernandez, Sajjad Ahmad
Effects Of Enso On Temperature, Precipitation, And Potential Evapotranspiration Of North India’S Monsoon: An Analysis Of Trend And Entropy, Kazi Tamaddun, Ajay Kalra, Miguel Bernandez, Sajjad Ahmad
Civil and Environmental Engineering and Construction Faculty Research
The influence of El Niño Southern Oscillation (ENSO) on the north Indian temperature, precipitation, and potential evapotranspiration (PET) change patterns were evaluated during the monsoon season across the last century. Trends and shifts in 146 districts were assessed using nonparametric statistical tests. To quantify their temporal variation, the concept of apportionment entropy was applied to both the annual and seasonal scales. Results suggest that the El Niño years played a greater role in causing hydro-climatological changes compared to the La Niña or neutral years. El Niño was more influential in causing shifts compared to trends. For certain districts, a phase …
A Graph-Based Reinforcement Learning Method With Converged State Exploration And Exploitation, Han Li, Tianding Chen, Hualiang Teng, Yingtao Jiang
A Graph-Based Reinforcement Learning Method With Converged State Exploration And Exploitation, Han Li, Tianding Chen, Hualiang Teng, Yingtao Jiang
Civil and Environmental Engineering and Construction Faculty Research
In any classical value-based reinforcement learning method, an agent, despite of its continuous interactions with the environment, is yet unable to quickly generate a complete and independent description of the entire environment, leaving the learning method to struggle with a difficult dilemma of choosing between the two tasks, namely exploration and exploitation. This problem becomes more pronounced when the agent has to deal with a dynamic environment, of which the configuration and/or parameters are constantly changing. In this paper, this problem is approached by first mapping a reinforcement learning scheme to a directed graph, and the set that contains all …