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A new methodology was developed for the real-time determination gate control operations of a river-reservoir system to minimize flooding conditions. The methodology is based upon an optimization-simulation model approach interfacing the genetic algorithm within MATLAB with simulation software for short-term rainfall forecasting, rainfall–runoff modeling (HEC-HMS), and a one-dimensional (1D), two-dimensional (2D), and combined 1D and 2D combined unsteady flow models (HEC-RAS). Both real-time rainfall data from next-generation radar (NEXRAD) and gaging stations, and forecasted rainfall are needed to make gate control decisions (reservoir releases) in real-time so that at time t, rainfall is known and rainfall over the future time-period (Δt) to time t + Δt can be forecasted. This new model can be used to manage reservoir release schedules (optimal gate operations) before, during, and after a rainfall event. Through real-time observations and optimal gate controls, downstream water surface elevations are controlled to avoid exceedance of threshold flood levels at target locations throughout a river-reservoir system to minimize the damage. In an example application, an actual river reach with a hypothetical upstream flood control reservoir is modeled in real-time to test the optimization-simulation portion of the overall model.
Hasan Albo-Salih; Larry Mays. Testing of an Optimization-Simulation Model for Real-Time Flood Operation of River-Reservoir Systems. Water 2021, 13, 1207 .
AMA StyleHasan Albo-Salih, Larry Mays. Testing of an Optimization-Simulation Model for Real-Time Flood Operation of River-Reservoir Systems. Water. 2021; 13 (9):1207.
Chicago/Turabian StyleHasan Albo-Salih; Larry Mays. 2021. "Testing of an Optimization-Simulation Model for Real-Time Flood Operation of River-Reservoir Systems." Water 13, no. 9: 1207.
Since prehistoric times, water conflicts have occurred as a result of a wide range of tensions and/or violence, which have rarely taken the form of traditional warfare waged over water resources alone. Instead, water has historically been a (re)source of tension and a factor in conflicts that start for other reasons. In some cases, water was used directly as a weapon through its ability to cause damage through deprivation or erosion or water resources of enemy populations and their armies. However, water conflicts, both past and present, arise for several reasons; including territorial disputes, fight for resources, and strategic advantage. The main reasons of water conflicts are usually delimitation of boundaries, waterlogging (e.g., dams and lakes), diversion of rivers flow, running water, food, and political distresses. In recent decades, the number of human casualties caused by water conflicts is more than that of natural disasters, indicating the importance of emerging trends on water wars in the world. This paper presents arguments, fights, discourses, and conflicts around water from ancient times to the present. This diachronic survey attempts to provide water governance alternatives for the current and future.
Andreas Angelakis; Mohammad Valipour; Abdelkader Ahmed; Vasileios Tzanakakis; Nikolaos Paranychianakis; Jens Krasilnikoff; Renato Drusiani; Larry Mays; Fatma El Gohary; Demetris Koutsoyiannis; Saifullah Khan; Luigi Giacco. Water Conflicts: From Ancient to Modern Times and in the Future. Sustainability 2021, 13, 4237 .
AMA StyleAndreas Angelakis, Mohammad Valipour, Abdelkader Ahmed, Vasileios Tzanakakis, Nikolaos Paranychianakis, Jens Krasilnikoff, Renato Drusiani, Larry Mays, Fatma El Gohary, Demetris Koutsoyiannis, Saifullah Khan, Luigi Giacco. Water Conflicts: From Ancient to Modern Times and in the Future. Sustainability. 2021; 13 (8):4237.
Chicago/Turabian StyleAndreas Angelakis; Mohammad Valipour; Abdelkader Ahmed; Vasileios Tzanakakis; Nikolaos Paranychianakis; Jens Krasilnikoff; Renato Drusiani; Larry Mays; Fatma El Gohary; Demetris Koutsoyiannis; Saifullah Khan; Luigi Giacco. 2021. "Water Conflicts: From Ancient to Modern Times and in the Future." Sustainability 13, no. 8: 4237.
Agricultural developments require changes in land surface and subsurface hydraulic functions as protection from floods, reclamation of flooded land, irrigation, and drainage. Drainage of agricultural land has a long history and apparently traces back to the earliest civilizations of Mesopotamia and Iran before 4000 BC. In the Eastern Mediterranean, the Minoan and Mycenaean civilizations developed techniques and strategies of drainage of agricultural lands from the middle of the 2nd millennium BC. After the collapse of the Aegean Bronze-age civilizations, society building and agricultural innovation in the archaic and Classical periods (ca. 800–300 BC) included successful attempts at controlling drainage and irrigation techniques. In addition, China, India, and Mesoamerica have extensive histories of drainage. The aim of this review paper is to trace the evolution of the main foundings on agricultural drainage technologies through the centuries until the present. This historical review reveals valuable insights into ancient hydraulic technologies as well as irrigation and drainage management that will help to find bright horizons for sustainable agriculture in future.
Mohammad Valipour; Jens Krasilnikof; Stavros Yannopoulos; Rohitashw Kumar; Jun Deng; Paolo Roccaro; Larry Mays; Mark E. Grismer; Andreas N. Angelakis. The Evolution of Agricultural Drainage from the Earliest Times to the Present. Sustainability 2020, 12, 416 .
AMA StyleMohammad Valipour, Jens Krasilnikof, Stavros Yannopoulos, Rohitashw Kumar, Jun Deng, Paolo Roccaro, Larry Mays, Mark E. Grismer, Andreas N. Angelakis. The Evolution of Agricultural Drainage from the Earliest Times to the Present. Sustainability. 2020; 12 (1):416.
Chicago/Turabian StyleMohammad Valipour; Jens Krasilnikof; Stavros Yannopoulos; Rohitashw Kumar; Jun Deng; Paolo Roccaro; Larry Mays; Mark E. Grismer; Andreas N. Angelakis. 2020. "The Evolution of Agricultural Drainage from the Earliest Times to the Present." Sustainability 12, no. 1: 416.
A new methodology is presented for real-time operation of water distribution systems (WDS) under the critical condition of limited electrical energy. The critical conditions could arise due to electric grid failure, extreme drought, or other severe conditions related to natural and artificial disasters such as sabotage, vandalism, terrorism, or war. The methodology presented considers both quantity and quality requirements of various water demands. The basic objective of optimizing water distribution system operations under limited availability of electrical power and/or water is to satisfy the required (requested) demand for service areas (or pressure zones) while meeting system pressure and water quality requirements of the system. The approach combines a genetic algorithm optimization procedure with the simulator EPANET in the framework of an optimal control problem. Combining the simulator and the genetic algorithm is accomplished within a MATLAB framework. The new methodology is illustrated using an example system incorporating both a WDS and electrical power distribution system (PDS) cooling-water system to evaluate the operations of the WDS under limited power supply conditions.
Puneet Khatavkar; Larry W. Mays. Model for Real-Time Operations of Water Distribution Systems under Limited Electrical Power Availability with Consideration of Water Quality. Journal of Water Resources Planning and Management 2018, 144, 04018071 .
AMA StylePuneet Khatavkar, Larry W. Mays. Model for Real-Time Operations of Water Distribution Systems under Limited Electrical Power Availability with Consideration of Water Quality. Journal of Water Resources Planning and Management. 2018; 144 (11):04018071.
Chicago/Turabian StylePuneet Khatavkar; Larry W. Mays. 2018. "Model for Real-Time Operations of Water Distribution Systems under Limited Electrical Power Availability with Consideration of Water Quality." Journal of Water Resources Planning and Management 144, no. 11: 04018071.
Reclaimed water (RW) is a reliable alternative water supply for irrigation in the agricultural sector, which is the predominant consumer of water in Iraq. A mixed-integer nonlinear programming reclaimed water allocation optimization model was developed to maximize the net benefit generated from the cultivation of different types of crops, comparing the use of reclaimed water type A (tertiary treated water), and reclaimed water type B (secondary treated water). The model was solved using the Algorithms for coNTinuous/Integer Global Optimization of Nonlinear Equations (ANTIGONE) optimizer in the general algebraic modeling system (GAMS). A total of 84 agricultural farms located on 5300 ha to the south of Baghdad, Iraq were available for irrigation with reclaimed water. Analysis considered varying quantities of available reclaimed water and different irrigation efficiencies (45–85%). The net benefits from using lower quantities of reclaimed water were similar for both types of reclaimed water, and the highest net benefit crop was cultivated on 384 ha. As the quantities of water increased, the amount of cultivated land increased and the net benefit per hectare decreased as the model required the cultivation of more crops with lower economic value. Irrigation with reclaimed water has potential to increase agricultural and economic activity adjacent to Baghdad.
Ahmed A. Aljanabi; Larry W. Mays; Peter Fox. Optimization Model for Agricultural Reclaimed Water Allocation Using Mixed-Integer Nonlinear Programming. Water 2018, 10, 1291 .
AMA StyleAhmed A. Aljanabi, Larry W. Mays, Peter Fox. Optimization Model for Agricultural Reclaimed Water Allocation Using Mixed-Integer Nonlinear Programming. Water. 2018; 10 (10):1291.
Chicago/Turabian StyleAhmed A. Aljanabi; Larry W. Mays; Peter Fox. 2018. "Optimization Model for Agricultural Reclaimed Water Allocation Using Mixed-Integer Nonlinear Programming." Water 10, no. 10: 1291.
A methodology for computation of system resilience for the real-time operation of water distribution systems (WDS) under critical conditions of limited water and limited electrical energy is presented. Critical emergencies in WDS operations can result from extreme drought, electric grid failure, and other severe natural conditions. The basic objective of this study is to apply the concepts of system resilience within an optimization-simulation model for real-time optimal operation of water distribution systems under conditions of limited water and energy availability. The modeling approach interfaces a genetic algorithm optimization procedure with the WDS hydraulic simulator (EPANET) in the framework of an optimal control problem. The methodology is implemented within the framework of MATLAB. An example WDS is used to demonstrate the application of the resilience concepts to assess the performance.
Puneet Khatavkar; Larry W. Mays. Resilience Computations for Optimal Operation of Water Distribution Systems. World Environmental and Water Resources Congress 2018 2018, 1 .
AMA StylePuneet Khatavkar, Larry W. Mays. Resilience Computations for Optimal Operation of Water Distribution Systems. World Environmental and Water Resources Congress 2018. 2018; ():1.
Chicago/Turabian StylePuneet Khatavkar; Larry W. Mays. 2018. "Resilience Computations for Optimal Operation of Water Distribution Systems." World Environmental and Water Resources Congress 2018 , no. : 1.
Climate change, pollution, civil conflicts, political instability, and a high rate of population growth all contribute to water shortages in Iraq which are predicted to increase in the future. Due to the importance of agriculture in Iraq which forms more than 75 percent of total demand, a sustainable agricultural water allocation scheme is necessary to find practical and applicable water conservation measures that helps mitigate the impact of potential droughts and water shortages. An agricultural irrigation reclaimed wastewater allocation optimization model was developed to optimally allocate crops and reclaimed wastewater (RW) on cultivated farmlands in order to maximize the net benefit. The optimization model is formulated using mixed-integer nonlinear programming (MINLP) solved by the branch and reduce optimization navigator (BARON) in the general algebraic mathematical solver (GAMS). The model maximizes the net farm income to determine the cultivated crop assigned to each farmland using three types of reclaimed wastewater (RW); tertiary treated wastewater; secondary treated wastewater; and primary treated wastewater. Constraints in the optimization model include: (1) reclaimed wastewater availability constraints and (2) irrigated farmlands constraints. The optimization model has been applied to 7045 hectares of farms located in the Alrustumia district to the south east of Baghdad, Iraq with 5.5 × 105 m3/d of treated wastewater. The use of tertiary treated wastewater provided the greatest net benefit under most scenarios evaluated while primary effluent provided the lowest net benefit as only low value crops could be cultivated.
Ahmed A. Aljanabi; Larry W. Mays; Peter Fox. A Reclaimed Wastewater Allocation Optimization Model for Agricultural Irrigation. Environment and Natural Resources Research 2018, 8, 55 .
AMA StyleAhmed A. Aljanabi, Larry W. Mays, Peter Fox. A Reclaimed Wastewater Allocation Optimization Model for Agricultural Irrigation. Environment and Natural Resources Research. 2018; 8 (2):55.
Chicago/Turabian StyleAhmed A. Aljanabi; Larry W. Mays; Peter Fox. 2018. "A Reclaimed Wastewater Allocation Optimization Model for Agricultural Irrigation." Environment and Natural Resources Research 8, no. 2: 55.
The magnitude of water resources shortages in the Middle East represents an important factor in the stability of the region and it is a vital element in protecting sustained economic development in the region. This investigation addresses the ongoing challenge of water governance in Iraq by examining how profitability, at both the farm and basin levels, is affected by various water appropriation systems. Farmland irrigation in Iraq was evaluated using three water appropriation systems; upstream (UPR), downstream (DPR) and proportional (PSR) sharing rule. Their impacts on farm income under normal, dry, and drought water supply scenarios were evaluated using an irrigation water model coupled with a nonlinear programming (NLP) optimization model. As compared to UPR, PSR provided a 32% and 75% increase in total farm income for the Tigris River under dry and drought supply conditions, respectively. As compared to DPR, PSR provided a 47% and 83.5% increase in total farm income for the Euphrates River under dry and drought supply conditions, respectively.
Ahmed A. Aljanabi; Larry W. Mays; Peter Fox. Application of an Optimization Model for Assessing the Performance of Water Appropriation in Iraq. Environment and Natural Resources Research 2017, 8, 105 .
AMA StyleAhmed A. Aljanabi, Larry W. Mays, Peter Fox. Application of an Optimization Model for Assessing the Performance of Water Appropriation in Iraq. Environment and Natural Resources Research. 2017; 8 (1):105.
Chicago/Turabian StyleAhmed A. Aljanabi; Larry W. Mays; Peter Fox. 2017. "Application of an Optimization Model for Assessing the Performance of Water Appropriation in Iraq." Environment and Natural Resources Research 8, no. 1: 105.
A new methodology for determining a sustainability index (SI) for the management of river basins is developed. Sustainability is defined in terms of minimizing the long-term risks to supply and maintaining the ecological, environmental and hydrological integrity of a river resource. The SI procedure developed uses two groups of performance criteria. The first group is based on demand-supply deficits and measures the risk to water supplies. The second group is only applied to river demands and compares a river’s allocation to a target flow regime using the Range of Variability Approach (RVA) and the Modified Hydrological Alteration factor. The RVA measures differences in flow regimes and is used to compare a projected flow regime to a targeted flow regime. This is the first attempt to use the RVA to develop a sustainability index for river basin management. A combined sustainability metric for the system (SS) is also determined. The methodology is applied to an area including the Prescott Active Management Area (AMA) in north-central Arizona. Sustainability for the entire system is determined using the weighted sum of the sustainability indices. The methodology has been used to measure and compare the sustainability of two allocation scenarios for the Prescott AMA.
Robert L. Oxley; Larry W. Mays. Sustainability Index for the Management of River Basins Based Upon Ecological, Environmental and Hydrological Integrity and the Minimization of Long Term Risks to Supply. Environment and Natural Resources Research 2017, 7, 1 .
AMA StyleRobert L. Oxley, Larry W. Mays. Sustainability Index for the Management of River Basins Based Upon Ecological, Environmental and Hydrological Integrity and the Minimization of Long Term Risks to Supply. Environment and Natural Resources Research. 2017; 7 (4):1.
Chicago/Turabian StyleRobert L. Oxley; Larry W. Mays. 2017. "Sustainability Index for the Management of River Basins Based Upon Ecological, Environmental and Hydrological Integrity and the Minimization of Long Term Risks to Supply." Environment and Natural Resources Research 7, no. 4: 1.
Puneet Khatavkar; Larry W. Mays; Jon E. Zufelt. Testing an Optimization/Simulation Model for the Real-Time Operations of Water Distribution Systems under Limited Power Availability. Congress on Technical Advancement 2017 2017, 1 -9.
AMA StylePuneet Khatavkar, Larry W. Mays, Jon E. Zufelt. Testing an Optimization/Simulation Model for the Real-Time Operations of Water Distribution Systems under Limited Power Availability. Congress on Technical Advancement 2017. 2017; ():1-9.
Chicago/Turabian StylePuneet Khatavkar; Larry W. Mays; Jon E. Zufelt. 2017. "Testing an Optimization/Simulation Model for the Real-Time Operations of Water Distribution Systems under Limited Power Availability." Congress on Technical Advancement 2017 , no. : 1-9.
An optimization model for pump operation based upon minimizing operation and maintenance costs of pumps for a specified demand (load) curve is presented. The purpose of this model is to determine pump operation to meet the known consumer demands as well as to satisfy the pressure requirements in the water distribution system. In addition, constraints on the number of pump (‘on-off’) switches are included as a surrogate to minimizing the maintenance costs. This model is a mixed integer nonlinear programming (MINLP) problem to consider the uncertainty in demand using a chance constraint formulation of the demand constraint. The optimization model was solved using the LocalSolver option in A Mathematical Programming Language (AMPL). The model was first applied to the operation of the example pumping system for an urban water distribution system (WDS) illustrating a reduction in operation costs using the optimization model. The optimization model with the chance-constraint on meeting demand was applied for a range of demand satisfaction uncertainties. A decrease in the operation costs was observed with an increased uncertainty in demand satisfaction, which shows that the model further optimizes the operations considering the relaxed constraints. Model application could be extended to operations of pumping systems during emergencies and contingencies such as droughts, component failures, etc.
Puneet Khatavkar; Larry W. Mays; Anna Pridmore; Jim Geisbush. Model for Optimal Operation of Water Distribution Pumps with Uncertain Demand Patterns. Pipelines 2017 2017, 1 .
AMA StylePuneet Khatavkar, Larry W. Mays, Anna Pridmore, Jim Geisbush. Model for Optimal Operation of Water Distribution Pumps with Uncertain Demand Patterns. Pipelines 2017. 2017; ():1.
Chicago/Turabian StylePuneet Khatavkar; Larry W. Mays; Anna Pridmore; Jim Geisbush. 2017. "Model for Optimal Operation of Water Distribution Pumps with Uncertain Demand Patterns." Pipelines 2017 , no. : 1.
Puneet Khatavkar; Larry W. Mays; Christopher N. Dunn; Brian Van Weele. Model for the Real-Time Operation of Water Distribution Systems under Limited Power Availability. World Environmental and Water Resources Congress 2017 2017, 171 -183.
AMA StylePuneet Khatavkar, Larry W. Mays, Christopher N. Dunn, Brian Van Weele. Model for the Real-Time Operation of Water Distribution Systems under Limited Power Availability. World Environmental and Water Resources Congress 2017. 2017; ():171-183.
Chicago/Turabian StylePuneet Khatavkar; Larry W. Mays; Christopher N. Dunn; Brian Van Weele. 2017. "Model for the Real-Time Operation of Water Distribution Systems under Limited Power Availability." World Environmental and Water Resources Congress 2017 , no. : 171-183.
Vegetative filter strips (VFS) are an effective methodology for runoff management and control of sediment flow and soil erosion, particularly for large urban parking lots, and for irrigation water management. An optimization model for the design of vegetative filter strips for runoff management, that minimizes the amount of land required for the strips, is developed herein. The resulting optimization model is based upon the kinematic wave equation for overland sheet flow along with equations defining the cumulative infiltration and infiltration rate. The nonlinear programming (NLP) optimization model has been applied using the General Algebraic Modeling System (GAMS). The runoff management model is extended for the control of sediment. These new models provide flexibility for site-specific conditions and are a step forward in the development of new design methodologies for stormwater and irrigation flow management. The optimization models have been applied using a sensitivity analysis of parameters such as different soil types, rainfall characteristics etc., performed to validate the model. Results of the example model applications indicate the usefulness of the models for practical applications in the field. To our knowledge this is the first optimization model developed for the design of vegetative filter strips for runoff and sediment control.
Puneet Khatavkar; Larry W. Mays. Optimization Models for the Design of Vegetative Filter Strips for Stormwater Runoff and Sediment Control. Water Resources Management 2017, 31, 2545 -2560.
AMA StylePuneet Khatavkar, Larry W. Mays. Optimization Models for the Design of Vegetative Filter Strips for Stormwater Runoff and Sediment Control. Water Resources Management. 2017; 31 (9):2545-2560.
Chicago/Turabian StylePuneet Khatavkar; Larry W. Mays. 2017. "Optimization Models for the Design of Vegetative Filter Strips for Stormwater Runoff and Sediment Control." Water Resources Management 31, no. 9: 2545-2560.
Application of an optimization/simulation model for the simulated real-time flood control for river-reservoir systems to the catastrophic May 2010 flood on the Cumberland River at Nashville, Tennessee is described. The optimization/simulation model includes five major components, including a hydrologic rainfall-runoff model, a hydraulic unsteady flow model, a short-term rainfall forecasting model, a reservoir operation model, and a genetic algorithm optimization model. The model application revealed that the reservoir upstream of Nashville was more contained and that an optimal gate release schedule could have decreased the floodwater levels in downtown Nashville below the 100-year flood stage. The application is for demonstrative purposes only, but does reflect the suitability of the optimization/simulation model for real-world application.
Daniel Che; Larry W. Mays. Application of an Optimization/Simulation Model for Real-Time Flood-Control Operation of River-Reservoirs Systems. Water Resources Management 2017, 31, 2285 -2297.
AMA StyleDaniel Che, Larry W. Mays. Application of an Optimization/Simulation Model for Real-Time Flood-Control Operation of River-Reservoirs Systems. Water Resources Management. 2017; 31 (7):2285-2297.
Chicago/Turabian StyleDaniel Che; Larry W. Mays. 2017. "Application of an Optimization/Simulation Model for Real-Time Flood-Control Operation of River-Reservoirs Systems." Water Resources Management 31, no. 7: 2285-2297.
There are many people on Earth today that live with severe water shortages and severe lack of sanitation, particularly among the poor. These people for the most part do not understand the knowledge base of methodologies of harvesting and conveying water and sanitation methods that have been around for thousands of years. A survey of ancient water technologies used in semi-arid and arid regions is presented in this paper. The survey will include methodologies used by Mesopotamians, the Persians, the Egyptians, and the Nabataeans. The attempt here is to explore how these traditional methods developed by the ancients in semi-arid and arid regions of the world could possibly be used to help solve the present-day water resources sustainability problems, especially in developing parts of the world. The advantages of the traditional knowledge of ancient water technologies are explored with the goal of determining ways to help poor people with water shortages and sanitation.
Larry W. Mays. Survey of ancient water technologies in semi-arid and arid regions: traditional knowledge for the future. Water Supply 2017, 17, 1278 -1286.
AMA StyleLarry W. Mays. Survey of ancient water technologies in semi-arid and arid regions: traditional knowledge for the future. Water Supply. 2017; 17 (5):1278-1286.
Chicago/Turabian StyleLarry W. Mays. 2017. "Survey of ancient water technologies in semi-arid and arid regions: traditional knowledge for the future." Water Supply 17, no. 5: 1278-1286.
An optimization model for the sustainable water resource management that maximizes sustainable net economic benefit over a long-term planning horizon is applied to the Prescott Active Management Area (Prescott AMA), a management area in north-central Arizona experiencing rapid population growth and limited water resources. Population growth in the Prescott AMA has stressed available water resources and a plan has been proposed to pump and transport ground-water from a remote location. Studies have suggested that pumping water at the proposed location will impact flows on the Verde River. Four scenarios were evaluated for purposes of validating the developed model, to gage the model viability, and to provide examples of potential application. This paper serves to illustrate the modeling capabilities available in the optimization model.
Robert L. Oxley; Larry W. Mays. Application of an Optimization Model for the Sustainable Water Resource Management of River Basins. Water Resources Management 2016, 30, 4883 -4898.
AMA StyleRobert L. Oxley, Larry W. Mays. Application of an Optimization Model for the Sustainable Water Resource Management of River Basins. Water Resources Management. 2016; 30 (13):4883-4898.
Chicago/Turabian StyleRobert L. Oxley; Larry W. Mays. 2016. "Application of an Optimization Model for the Sustainable Water Resource Management of River Basins." Water Resources Management 30, no. 13: 4883-4898.
Throughout history, various civilizations developed methodologies for the collection and disposal of human waste. The methodologies throughout the centuries have been characterized by technological peaks on the one hand, and by the disappearance of the technologies and their reappearance on the other. The purpose of this article is to trace the development of sewage collection and transport with an emphasis on toilets in ancient civilizations. Evolution of the major achievements in the scientific fields of sanitation with emphasis on the lavatory (or toilets) technologies through the centuries up to the present are presented. Valuable insights into ancient wastewater technologies and management with their apparent characteristics of durability, adaptability to the environment, and sustainability are provided. Gradual steps improved the engineering results until the establishment of the contemporary toilet system, which provides a combined solution for flushing, odor control, and the sanitation of sewerage. Even though the lack of proper toilet facilities for a great percentage of the present day global population is an embarrassing fact, the worldwide efforts through millennia for the acquisition of a well-engineered toilet were connected to the cultural level of each period.
Georgios P. Antoniou; Giovanni De Feo; Franz Fardin; Aldo Tamburrino; Saifullah Khan; Fang Tie; Ieva Reklaityte; Eleni Kanetaki; Xiao Yun Zheng; Larry W. Mays; Andreas N. Angelakis. Evolution of Toilets Worldwide through the Millennia. Sustainability 2016, 8, 779 .
AMA StyleGeorgios P. Antoniou, Giovanni De Feo, Franz Fardin, Aldo Tamburrino, Saifullah Khan, Fang Tie, Ieva Reklaityte, Eleni Kanetaki, Xiao Yun Zheng, Larry W. Mays, Andreas N. Angelakis. Evolution of Toilets Worldwide through the Millennia. Sustainability. 2016; 8 (8):779.
Chicago/Turabian StyleGeorgios P. Antoniou; Giovanni De Feo; Franz Fardin; Aldo Tamburrino; Saifullah Khan; Fang Tie; Ieva Reklaityte; Eleni Kanetaki; Xiao Yun Zheng; Larry W. Mays; Andreas N. Angelakis. 2016. "Evolution of Toilets Worldwide through the Millennia." Sustainability 8, no. 8: 779.
This paper presents a new methodology for the sustainable and optimal allocation of water for a river basin management area. The model distinguishes between short and long-term planning horizons and goals using a short-term modeling component (STM) and a long term modeling component (LTM) respectively. An STM is a linear programming problem, and optimizes a monthly allocation schedule on an annual basis in terms of maximum net economic benefit. A cost of depletion is included in the STM net benefit calculation to address the non-use value of groundwater. An LTM consists of an STM for every year of the long-term planning horizon. Each LTM is quantified using a sustainability index, with sustainability defined in terms of risk to supply and ecological, environmental, and hydrological integrity. The LTMs are optimized to determine the most sustainable net economic benefit for the management area using a genetic algorithm. The model is applied to a test case representative of a management area in Arizona in order to highlight its potential utility.
Robert L. Oxley; Larry W. Mays; Alan Murray. Optimization Model for the Sustainable Water Resource Management of River Basins. Water Resources Management 2016, 30, 3247 -3264.
AMA StyleRobert L. Oxley, Larry W. Mays, Alan Murray. Optimization Model for the Sustainable Water Resource Management of River Basins. Water Resources Management. 2016; 30 (9):3247-3264.
Chicago/Turabian StyleRobert L. Oxley; Larry W. Mays; Alan Murray. 2016. "Optimization Model for the Sustainable Water Resource Management of River Basins." Water Resources Management 30, no. 9: 3247-3264.
The design of urban stormwater systems and sanitary sewer systems consists of solving two problems: generating a layout of the system and the pipe design which includes the crown elevations, slopes and commercial pipe sizes. A heuristic model for determining the optimal (minimum cost) layout and pipe design of a storm sewer network is presented. The hierarchical procedure combines a sewer layout model formulated as a mixed-integer nonlinear programming (MINLP) problem which is solved using the General Algebraic Modeling System (GAMS) and a simulated annealing optimization procedure for the pipe design of a generated layout was developed in Excel. The GAMS and simulated annealing models are interfaced through linkage of Excel and GAMS. The pipe design model is based upon the simulated annealing method to optimize the crown elevations and diameter of pipe segments in a storm sewer network using layouts generated using GAMS. A sample scenario demonstrates that using these methods may allow for significant costs saving while simultaneously reducing the time typically required to design and compare multiple storm sewer networks.
Joshua C. Steele; Kurt Mahoney; Omer Karovic; Larry W. Mays. Heuristic Optimization Model for the Optimal Layout and Pipe Design of Sewer Systems. Water Resources Management 2016, 30, 1605 -1620.
AMA StyleJoshua C. Steele, Kurt Mahoney, Omer Karovic, Larry W. Mays. Heuristic Optimization Model for the Optimal Layout and Pipe Design of Sewer Systems. Water Resources Management. 2016; 30 (5):1605-1620.
Chicago/Turabian StyleJoshua C. Steele; Kurt Mahoney; Omer Karovic; Larry W. Mays. 2016. "Heuristic Optimization Model for the Optimal Layout and Pipe Design of Sewer Systems." Water Resources Management 30, no. 5: 1605-1620.
Real-time optimal operation models for river-reservoir systems, unfortunately, are not widely available. Such models are still in their infancy perhaps due to the complexity of the application. This paper presents the development and testing of a methodology for determining reservoir release schedules before, during, and after an extreme flood event in real time. The problem is formulated as a real-time optimal control problem in which reservoir releases represent the decision variables. The model consists of five major components: (1) the U.S. Army Corps of Engineers (USACE) Hydrologic Engineering Center - Hydrologic Modeling System (HEC-HMS), which simulates rainfall-runoff processes of watershed systems; (2) the U.S. Army Corps of Engineers Hydrologic Engineering Center - River Analysis System (HEC-RAS) for one-dimensional unsteady flow routing; (3) a reservoir release operation model; (4) a short-term rainfall forecasting model to project rainfall over the next few hours during a rainfall event; and (5) a genetic algorithm (GA) optimizer interfaced with the other components that determine the real time operation of a river-reservoir systems. An example application is used to test the development of the modeling framework, also illustrating the use of such a model. Each model component and its interface in the modeling framework was tested for quality assurance.
Daniel Che; Larry W. Mays. Development of an Optimization/Simulation Model for Real-Time Flood-Control Operation of River-Reservoirs Systems. Water Resources Management 2015, 29, 3987 -4005.
AMA StyleDaniel Che, Larry W. Mays. Development of an Optimization/Simulation Model for Real-Time Flood-Control Operation of River-Reservoirs Systems. Water Resources Management. 2015; 29 (11):3987-4005.
Chicago/Turabian StyleDaniel Che; Larry W. Mays. 2015. "Development of an Optimization/Simulation Model for Real-Time Flood-Control Operation of River-Reservoirs Systems." Water Resources Management 29, no. 11: 3987-4005.