hydrological drought refers to a persistently low discharge and volume of water in streams and reservoirs, lasting months or years. hydrological drought is a natural phenomenon, but it may be exacerbated by human activities. hydrological droughts are usually related to meteorological droughts, and their recurrence interval varies accordingly. this study pursues to identify a stochastic model (o...

Flood forecasting is always a challenge in Taiwan, which has a subtropical climate and high mountains. This paper develops a fuzzy clustering neural network (FCNN), and implements this novel structure and reasoning process for flood forecasting. The FCNN has a hybrid learning scheme; the unsupervised learning scheme employs fuzzy min-max clustering to extract information from the input data. Th...

physiographic characteristics and climatic conditions are factors which contributing to river flow regime and understanding of relations between these factors and river flow in a basin result in its application for the ungauged sub-basins river flow prediction. in this research the relation between physiographic and climatic parameters of golestan province and rivers flow were examined by appli...

Heavy metal pollution dispersion simulation in rivers and predicting spatial and temporal variations of pollutants can be used to determine the precise place and to schedule water withdrawal time for drinking, agriculture, aquaculture and ecosystem studies. To study the movement of heavy metal pollution through Karoon flow model, MIKE 11 was employed fpr simulation of the flow model of Karoon R...

This paper presents an alternative approach to time series forecasting, through use of artificial neural networks (ANNs), a relatively new concept in hydrological research. Box and Jenkins ARMAX (autoregressive moving average with exogenous inputs) models have been widely used in modeling various time series with satisfactory results. This study shows that ANNs can produce comparable, to ARMAX,...

Investigating the features and flow behavior and related component is one of the complex phenomena that make using of software inevitable. The rivers carry sediment content along with water which is created by erosion of riverbed sediment and erosion caused by rainfall or surface runoff flowing over the catchment area. If the action of river dewatering occurs, the entry of sediment into the int...

1. River management involves satisfying societal preferences alongside environmental needs for a healthy river ecosystem. Environmental flows is a discipline that aims to define streamflow requirements that achieve desired social and ecological conditions in rivers. 2. The ecological limits of hydrologic alteration (ELOHA) framework takes a regional approach towards assessing relationships betw...

abstract due to transmission losses and lack of initial flow, flood routing in ephemeral streams is not possible with common methods and it is necessary the flood routing models have been developed for these streams. therefore in this study a computer model for natural river cross section has been developed in that after linearization of partial differential equations of unsteady none uniform f...