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Full-Text Articles in Engineering
Modular Neural Network To Predict The Distribution Of Nitrate In Ground Water Using On-Ground Nitrogen Loading And Recharge Data, M. Almasri, Jagath J. Kaluarachchi
Modular Neural Network To Predict The Distribution Of Nitrate In Ground Water Using On-Ground Nitrogen Loading And Recharge Data, M. Almasri, Jagath J. Kaluarachchi
Civil and Environmental Engineering Faculty Publications
Artificial neural networks have proven to be an attractive mathematical tool to represent complex relationships in many branches of hydrology. Due to this attractive feature, neural networks are increasingly being applied in subsurface modeling where intricate physical processes and lack of detailed field data prevail. In this paper, a methodology using modular neural networks (MNN) is proposed to simulate the nitrate concentrations in an agriculture-dominated aquifer. The methodology relies on geographic information system (GIS) tools in the preparation and processing of the MNN input–output data. The basic premise followed in developing the MNN input–output response patterns is to designate the …
Assessment Of Aquifer Vulnerability Due To Heavy Metals Using Ordinal Logistic Regression Analysis, N. K. Twarakavi, Jagath J. Kaluarachchi
Assessment Of Aquifer Vulnerability Due To Heavy Metals Using Ordinal Logistic Regression Analysis, N. K. Twarakavi, Jagath J. Kaluarachchi
Civil and Environmental Engineering Faculty Publications
A methodology using ordinal logistic regression is proposed to predict the probability of occurrence of heavy metals in ground water. The predicted probabilities are defined with reference to the background concentration and the maximum contaminant level. The model is able to predict the occurrence due to different influencing variables such as the land use, soil hydrologic group (SHG), and surface elevation. The methodology was applied to the Sumas-Blaine Aquifer located in Washington State to predict the occurrence of five heavy metals. The influencing variables considered were (1) SHG; (2) land use; (3) elevation; (4) clay content; (5) hydraulic conductivity; and …
Multi-Criteria Decision Analysis For The Optimal Management Of Nitrate Contamination Of Aquifers, Mohammad N. Almasri, Jagath J. Kaluarachchi
Multi-Criteria Decision Analysis For The Optimal Management Of Nitrate Contamination Of Aquifers, Mohammad N. Almasri, Jagath J. Kaluarachchi
Civil and Environmental Engineering Faculty Publications
We present an integrated methodology for the optimal management of nitrate contamination of ground water combining environmental assessment and economic cost evaluation through multi-criteria decision analysis. The proposed methodology incorporates an integrated physical modeling framework accounting for on-ground nitrogen loading and losses, soil nitrogen dynamics, and fate and transport of nitrate in ground water to compute the sustainable on-ground nitrogen loading such that the maximum contaminant level is not violated. A number of protection alternatives to stipulate the predicted sustainable on-ground nitrogen loading are evaluated using the decision analysis that employs the importance order of criteria approach for ranking and …
Optimizing Integrated Water Resources Management: Data, Tools, And Examples, Richard C. Peralta
Optimizing Integrated Water Resources Management: Data, Tools, And Examples, Richard C. Peralta
Civil and Environmental Engineering Faculty Publications
Best utilizing water resources requires coordinating their availability and use in time and space. Required can be: spatially and temporally distributed data; simulators to predict system response to stimuli; procedures for defining management goals, constraints, and scenarios; optimizers to compute optimal management strategies; and appropriate strategy implementation techniques. Here, a strategy is a set of controllable groundwater extraction and injection rates and surface water diversions. Simulation/optimization (S/O) models couple simulators and optimizers to compute optimal strategies for posed management problems. S/O models are becoming more commonly used for policy, planning, system design, and management. For example, water planners and managers …
Beneficial Reuse And Sustainability: The Fate Of Organic Compounds In The Land-Applied Waste, M. R. Overcash, Ronald C. Sims, J. L. Sims, K. C. Nieman
Beneficial Reuse And Sustainability: The Fate Of Organic Compounds In The Land-Applied Waste, M. R. Overcash, Ronald C. Sims, J. L. Sims, K. C. Nieman
Biological Engineering Faculty Publications
Land application systems, also referred to as beneficial reuse systems, are engineered systems that have defined and permitted application areas based on site and waste characteristics to determine the land area size requirement. These terrestrial systems have orders of magnitude greater microbial capability and residence time to achieve decomposition and assimilation compared with aquatic systems. In this paper we focus on current information and information needs related to terrestrial fate pathways in land treatment systems. Attention is given to conventional organic chemicals as well as new estrogenic and pharmaceutical chemicals of commerce. Specific terrestrial fate pathways addressed include: decomposition, bound …