A hybrid time series-nonparametric sampling approach, referred to herein as semiparametric, is presented for the estimation of model predictive uncertainty. The methodology is a two-step procedure whereby a distributed hydrologic model is first calibrated, then followed by brute force application of time series analysis with nonparametric random generation to synthesize serially correlated mode...

River science and management often require a design or reference discharge. The common (and sometimes unavoidable) use of such discharges may, however, obscure the fact that the magnitude and frequency of critical flows can differ due to various hydrological, geomorphological, and ecological criteria. Threshold stages and discharges were identified for six lower Brazos River, Texas gaging stati...

Flood estimation can be performed on the basis of event-based simulation or continuous simulation. A model with continuous water balance accounting has the attractive feature that dynamic factors affecting runoff production may be represented explicitly (Lamb 1999). In particular, a conceptual rainfall-runoff model can simulate the changing antecedent moisture conditions that determine the catc...

In the aggregate freight demand modeling literature, temporal assignment (annual to daily flows) is often oversimplified or neglected altogether. Unlike passenger flows, freight flows over the course of a year are not uniform and can vary significantly as the result of trade-offs between inventory and transportation cost management. We introduce the first temporal assignment model that explicit...

An Artificial Neural Network is a flexible mathematical structure which is capable of identifying complex nonlinear relationships between input and output data sets. Such Neural Networks have been characterized by passive neurons that are not able to select and estimate their own inputs. In a new approach, which corresponds in a better way to the actions of human nervous system, the connections...

Successive daily peak flows from hydropower plants can disrupt aquatic ecosystems and alter the composition and structure of macroinvertebrates downstream. We evaluated the influence of peak flow changes on macroinvertebrate drift downstream of a hydroelectric plant as a basis for determining ecological flows that might reduce the disturbance of aquatic biota. The aim of this study was to asses...

abstract given the importance of environmental cycles had led to allocation of water-right for water species and ecosystems which is known as environmental flow or in stream flow. from among the various methods for estimating environmental flow, building block approach is considered as a very powerful tool for estimating the water needs. in this paper, beside simplifying the building block appr...