Hydraulic parameters of culverts from pipes with normal and spiral form of corrugation

1990 ◽

Vol 48 (3) ◽

pp. 626-627

Author(s):

A. R. Crooker ◽

W. G. Kraft ◽

T. L. Beard ◽

M. C. Myers

Keyword(s):

Helicobacter Pylori ◽

Growth Cycle ◽

Negative Bacterium ◽

Body Formation ◽

Coccoid Form ◽

Spiral Form ◽

Prolonged Culture ◽

H Pylori ◽

Upper Gastrointestinal

Helicobacter pylori is a microaerophilic, gram-negative bacterium found in the upper gastrointestinal tract of humans. There is strong evidence that H. pylori is important in the etiology of gastritis; the bacterium may also be a major predisposing cause of peptic ulceration. On the gastric mucosa, the organism exists as a spiral form with one to seven sheathed flagella at one (usually) or both poles. Short spirals were seen in the first successful culture of the organism in 1983. In 1984, Marshall and Warren reported a coccoid form in older cultures. Since that time, other workers have observed rod and coccal forms in vitro; coccoid forms predominate in cultures 3-7 days old. We sought to examine the growth cycle of H. pylori in prolonged culture and the mode of coccoid body formation.

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Measurement of Thermal-Hydraulic Parameters in Liquid-Metal-Cooled Fast Breeder Reactors

Proceeding of Advanced Course in Measurement Techniques in Heat and MassTransfer ◽

10.1615/ichmt.1985.advcoursemeastechheatmasstransf.190 ◽

1985 ◽

Author(s):

John I. Sackett

Keyword(s):

Liquid Metal ◽

Hydraulic Parameters ◽

Fast Breeder Reactors ◽

Breeder Reactors

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Estimation of hydraulic parameters from an unconfined aquifer test conducted in a glacial outwash deposit, Cape Cod, Massachusetts

Open-File Report ◽

10.3133/ofr00485 ◽

2000 ◽

Cited By ~ 2

Author(s):

A.F. Moench ◽

Stephen P. Garabedian ◽

Denis R. LeBlanc

Keyword(s):

Unconfined Aquifer ◽

Cape Cod ◽

Hydraulic Parameters ◽

Aquifer Test ◽

Glacial Outwash ◽

Outwash Deposit

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Spatial Variation of Aquifer Parameters from Coastal Aquifers of Sindhudurg District, Maharashtra Using Pore-water Resistivity and Bulk Resistivity

10.21523/gcj3.17010104 ◽

2018 ◽

Vol 1 (1) ◽

pp. 28-40

Author(s):

Suneetha Naidu ◽

Gautam Gupta

Keyword(s):

Hydraulic Conductivity ◽

Pore Water ◽

Coastal Aquifers ◽

Hydraulic Parameters ◽

Formation Factor ◽

Bulk Resistivity ◽

Good Correspondence ◽

Aquifer System ◽

Transverse Resistance ◽

Water Resistivity

Estimation of hydraulic parameters in coastal aquifers is an important task in groundwater resource assessment and development. An attempt is made to estimate these parameters using geoelectrical data in combination with pore-water resistivity of existing wells. In the present study, 29 resistivity soundings were analysed along with 29 water samples, collected from the respective dug wells and boreholes, in order to compute hydraulic parameters like formation factor, porosity, hydraulic conductivity and transmissivity from coastal region of north Sindhudurg district, Maharashtra, India. The result shows some parts of the study area reveal relatively high value of hydraulic conductivity, porosity and transmissivity. Further, a negative correlation is seen between hydraulic conductivity and bulk resistivity. The hydraulic conductivity is found to vary between 0.014 and 293 m/day, and the transmissivity varied between 0.14 and 11,722 m2/day. The transmissivity values observed here are in good correspondence with those obtained from pumping test data of Central Ground Water Board. These zones also have high aquifer thickness and therefore characterize high potential within the water-bearing formation. A linear, positive relationship between transverse resistance and transmissivity is observed, suggesting increase in transverse resistance values indicate high transmissivity of aquifers. These relations will be extremely vital in characterization of aquifer system, especially from crystalline hard rock area.

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Study of hydraulic parameters for concreting channels

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/614/1/012054 ◽

2020 ◽

Vol 614 ◽

pp. 012054

Author(s):

A Fatxulloyev ◽

D Allayorov ◽

M Otakhonov

Keyword(s):

Hydraulic Parameters

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A Parametric Approach for Determining Fishway Attraction Flow at Hydropower Dams

Water ◽

10.3390/w13050743 ◽

2021 ◽

Vol 13 (5) ◽

pp. 743

Author(s):

Patrick Heneka ◽

Markus Zinkhahn ◽

Cornelia Schütz ◽

Roman B. Weichert

Keyword(s):

Input Data ◽

Design Criterion ◽

Hydraulic Parameters ◽

Parametric Approach ◽

Temporal Complexity ◽

Hydropower Plants ◽

Hydropower Dams ◽

Migration Corridor ◽

Zone Characteristic ◽

Good Agreement

High discharges at hydropower plants (HPP) may mask fishway attraction flows and, thereby, prevent fishes from locating and using fishways critical for their access to upstream spawning and rearing habitats. Existing methods for determining attraction flows are either based on simple guidelines (e.g., a proportion of HPP discharge) that cannot address the spatial and temporal complexity of tailrace flow patterns or complicated studies (e.g., combinations of detailed hydraulic and biological investigations) that are expensive and time-consuming. To bridge this gap, we present a new, intermediate approach to reliably determine attraction flows for technical fishways at small to medium-sized waterways (mean annual flow up to 400 m3/s). Fundamental to our approach is a design criterion that the attraction flow should maintain its integrity as it propagates downstream from the fishway entrance to beyond the highly turbulent zone characteristic of HPP tailraces to create a discernable migration corridor connecting the fishway entrance to the downstream river. To implement this criterion, we describe a set of equations to calculate the width of the entrance and the corresponding attraction discharge. Input data are usually easy to obtain and include geometrical and hydraulic parameters describing the target HPP and its tailrace. To confirm our approach, we compare model results to four sites at German waterways where the design of attraction flow was obtained by detailed experimental and numerical methods. The comparison shows good agreement supporting our approach as a useful, intermediate alternative for determining attraction flows that bridges the gap between simple guidelines and detailed hydraulic and biological investigations.

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