this study proposed a new discharge estimation method using a mean velocity formula derived from chiu’s 2d velocity formula of probabilistic entropy concept and the river bed shear stress of channel. in particular, we could calculate the mean velocity, which is hardly measurable in flooding natural rivers, in consideration of several factors reflecting basic hydraulic characteristics such as ri...

A large amount of the water diverted for irrigated agriculture seeps from earthen canals during its conveyance to fields. Besides a shortfall in availability, variety environmental and economic damages are caused by canal seepage . Polymer sealants provide an economical alternative permanent liners reducing temporarily. Field studies polymer sealant linear anionic polyacrylamide (LAPAM) conduct...

Instream flow needs (IFN) assessment studies are performed to provide guidelines for stream water management and to assess the impacts of different water projects such as weirs, dams and stream diversions on the available fish habitat. The physical habitat simulation is one of the IFN assessment methods and also a powerful tool in management of river ecosystem that has not become a common metho...

the variety of sprinkler devices available for the center pivot and linear irrigation systems has been increased dramatically in recent years. in the current study, via conducting some indoor experiments, one type of fixed pad spray sprinkler (d3000) and two types of moving pad spray sprinklers (r3000 and s3000) with various configurations (working pressure, nozzle size and type of deflector pa...

Separation of certain bacteria from liquids is important in the food, water quality management, bioengineering, and pharmaceutical industries. In this study, we developed a microfluidic device for the hydrodynamic separation of motile bacteria (Escherichia coli) using drift velocity. We first investigated drift tendencies of bacteria and found that cells tended to move in a spanwise direction w...

The hyporheic zone of three reaches of Sycamore Creek, Arizona consisted of an average 63 cm depth of predominantly sand or fine gravel (0.5-5 mm). Sediments were highly porous (1923% interstitial space) and interstitial water volume was 3-4 times that of surface water. Spatial distribution of temperature, sediment organic matter, interstitial nutrients, and subsurface oxygen indicate that phys...