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Full-Text Articles in Engineering
Ground-Water Policy-Making Support: Usem Optimization Modelling Plus Gis And Graphics, Richard C. Peralta, Christopher M. U. Neale, Ali Gharbi, Mazibur Khan, Oscar Daza, Douglas Ramsey, Kurt Vest
Ground-Water Policy-Making Support: Usem Optimization Modelling Plus Gis And Graphics, Richard C. Peralta, Christopher M. U. Neale, Ali Gharbi, Mazibur Khan, Oscar Daza, Douglas Ramsey, Kurt Vest
Civil and Environmental Engineering Faculty Publications
A support tool for ground-water management decision making involves integration of a multiobjective optimization model, GIS and graphics software. Two results are improved consideration of spatial data within the optimization model and improved conversion of optimal strategies to real-world application. Another result is improved visualization of the trade-offs involved between conflicting management goals.
Us/Wells Vs. 1.05 User's Manual, Alaa H. Aly, Richard C. Peralta
Us/Wells Vs. 1.05 User's Manual, Alaa H. Aly, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
Presented is a computer program, US/WELLS, that is designed to solve several types of groundwater management problems. The acronym US/WELLS stands for Utah State WELL System. This decision-support tool is usable by persons slightly familiar with groundwater hydraulics. It can be valuable for practical management of groundwater systems that satisfy certain criteria.
Sprinkler Irrigation-Pesticide Best Management Systems, A. Y. Ranjha, Richard C. Peralta, Robert W. Hill, A. M. Requena, Howard M. Deer, M. Ehteshami
Sprinkler Irrigation-Pesticide Best Management Systems, A. Y. Ranjha, Richard C. Peralta, Robert W. Hill, A. M. Requena, Howard M. Deer, M. Ehteshami
Civil and Environmental Engineering Faculty Publications
The relative reduction in potential groundwater contamination due to pesticides at several sites in Utah was determined by comparing alternative irrigation system designs, water management practices, and pesticides. Alternative sprinkler irrigation distribution coefficients were used to estimate irrigation application depths. The movement of pesticides through soils following sprinkler irrigations was simulated with a one-dimensional model. Pesticide contamination of groundwater can be reduced by careful selection of pesticides, using properly designed irrigation systems, and improved water management techniques. Procedures for selecting an appropriate sprinkler system design and pesticide are presented. KEYWORDS. Pesticides, Leaching, Sprinkler irrigation, Irrigation depth, Irrigation system design, Soil, …
Optimal Linear/Nonlinear, Quantity/Quality Management Of Complex Multilayer Aquifers By Embedding, Ali Gharbi, Richard C. Peralta
Optimal Linear/Nonlinear, Quantity/Quality Management Of Complex Multilayer Aquifers By Embedding, Ali Gharbi, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
The embedding optimization modelling approach is adapted to aid long-term groundwater quality and quantity management of complex nonlinear multilayer aquifers. Implicit block-centered finite-difference approximations of the quasi-three-dimensional unsteady flow equation, and Galerkin finite-element approximations of the twodimensional advection-dispersion transport equation are embedded as constraints in the model. Other hydrological processes are also included as constraints. Cyclical linear differencing permits representation of nonlinear transport, even when contaminant is extracted by unsteady pumping (a decision variable). Also used are nonlinear (discontinuous derivative) constraints describing drainage, stream-aquifer interflow and evapotranspiration. The use of both linear and nonlinear formulations of the entire flow and …
Best Management Practices (Bmps) To Minimize Nitrate Leaching From Irrigated Potatoes, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill
Best Management Practices (Bmps) To Minimize Nitrate Leaching From Irrigated Potatoes, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill
Civil and Environmental Engineering Faculty Publications
Numerous preliminary simulations are again performed to determine the smallest fertilizer amount, applied througii sprinkler irrigations (chemigation), that should still yield 15.3 tons of potatoes per acre. Applying only 68 lbs/ac of ammonium nitrate fertilizer in the first irrigation on June 28, should be sufficient. Again, total crop N uptake equals potential crop N uptake throughout the growing season. Except for the net income and applied fertilizer N uptake efficiency, all the other results computed by NLEAP (Figure 4 and Table 1) are very similar to results of scenario II. Applied fertilizer N uptake efficiency is the highest (91%) in …
Optimal Perennial Groundwater Yield Planning For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta
Optimal Perennial Groundwater Yield Planning For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
Computer models are developed for computing optimal perennial groundwater withdrawal strategies for the East Shore Area of Utah's Great Salt Lake. The underlying aquifer has three confined or unconfined layers. Both embedding and response matrix (RM) approaches are tested and compared. Historically, it has been difficult to incorporate simulation of an unconfined aquifer and many external flow equations described by nonsmooth functions within linear programming models. RM models normally assume system linearity. The presented RM model overcomes this difficulty using cycling and influence coefficients generated with a modified MODFLOW model. In this groundwater flow simulation model, the above nonlinear terms …
Optimal Groundwater Quantity/Quality Planning For Salt Lake Valley, Ali Gharbi, Richard C. Peralta
Optimal Groundwater Quantity/Quality Planning For Salt Lake Valley, Ali Gharbi, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
Generally, the embedding technique for optimizing groundwater management has been limited to small scale or steady-state groundwater flow management cases. The embedding approach causes sparse, highly structured constraint matrices which have been sometimes difficult to solve. Embedding applications have been limited by lack of: optimization algorithms able to easily address such matrices for large scale problems, and efficient methods for addressing common nonlinearities and converging to a solution. Computer software, USUEM, addresses these issues by: creation of alternative linear, nonlinear, combined and partitioned formulations of the same problem, implemention of an efficient cycling procedure, and good selection of optimization algorithm …
Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta
Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
No abstract provided.
Maximizing Sustainable Ground-Water Withdrawals: Comparing Accuracy And Computational Requirements For Steady-State And Transient Digital Modeling Approaches, Richard C. Peralta, R. R.A. Cantiller, Gary L. Mahon
Maximizing Sustainable Ground-Water Withdrawals: Comparing Accuracy And Computational Requirements For Steady-State And Transient Digital Modeling Approaches, Richard C. Peralta, R. R.A. Cantiller, Gary L. Mahon
Civil and Environmental Engineering Faculty Publications
Rigorous models for maximizing sustainable groundwater withdrawals may require more computer memory for their constraint set than is available. In some situations, alternative constraint formulations yield similar or identical answers resulting in great saving in computer memory requirements. In order to evaluate the efficiency of using alternative constraints1 maximum ground-water withdrawal pumping strategies were computed by three digital models for a hypothetical area for a five-decade period. Model A maximized steady ground-water withdrawal. Model B maximized unsteady ground-water mining. Model C maximized unsteady ground-water mining subject to a constraint that final pumping be sustainable after the end of the 50-year …
Fate And Transport Of Tce-Petroleum Hydrocarbon Mixture At Uttr, G. Nash Quashiga, Richard C. Peralta
Fate And Transport Of Tce-Petroleum Hydrocarbon Mixture At Uttr, G. Nash Quashiga, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
In 1988 a preliminary assessment (PA) study was conducted at Chemical Disposal Pit No. 4 to address several concerns of Hill Air Force Base (HAFB), the facility operators. The objectives of the PA were; i) to assess the potential for organic chemical releases to the subsurface environment, and ii) to determine the need for any immediate control measures, if the subsurface environment were threatened.
Optimizing Perennial Groundwater Yield Planning For Nonlinear Systems: Approach Comparison, Shu Takahashi, Richard C. Peralta
Optimizing Perennial Groundwater Yield Planning For Nonlinear Systems: Approach Comparison, Shu Takahashi, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
Four alternative simulation/optimization models useful for computing optimal sustained-yield (steady-state) groundwater pumping strategies are compared in terms of formulation, solution procedure, accuracy, and computational efficiency. The different models require different computer processing time and memory. For the aquifer tested system, if more than 10% of the cells have pumping as a decision variable, a fully linearized embedding model will require less computer memory than any other model. All the models address linear and nonlinear steady-state flow in multilayer, unconfined/confined aquifers. They also address several types of nonsmooth external flows. Newly presented are a response matrix model solving external flows described …
Optimal Management Of Irrigation And Vadose Zone Pesticide Transport, M. A. Hegazy, Richard C. Peralta
Optimal Management Of Irrigation And Vadose Zone Pesticide Transport, M. A. Hegazy, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
A management model is developed for maximizing crop yield while avoiding unacceptable pesticide leaching. Utilized constraint equations: maintain a soil moisture volume balance, describe downward pesticide transport, and limit the amount of pesticide reaching groundwater. The reported optimization model is the first which includes unsaturated zone pesticide transport. It is designed to help prevent nonpoint-source contamination of shallow groundwater aquifers. The model computes optimal irrigation amounts for given soil, crop, chemical, and climate data and irrigation frequencies. The model is tested for different irrigation scenarios. The modeling approach is promising as a tool to aid developing environmentally sound agricultural production …
Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson
Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson
Civil and Environmental Engineering Faculty Publications
Simulation/optimization (S/0) models can be used to speed the process of computing long term groundwater pumping strategies. These combined models can also greatly ease the planning tasks of water management agencies. They make the process of computing optimal perennial yield groundwater management strategies fairly straightforward. S/0 models dramatically improve conjunctive water management and can help minimize the cost of groundwater contaminant clean-up. The differences between S/0 models and the simulation (S) models currently used by over 98 % of practitioners are illustrated with recent applications of S/0 models in regional planning.