T Measurements for Irrigation of Sweet Corn
Commonly used scheduling methods are based on a water balance approach where evapotranspiration (ET) must be either estimated from climatic data or by soil water depletion measurements....

Steady State Fluid Transport Model for Plants
Knowledge of water potentials throughout the xylem and phloem elements as well as in individual cells is fundamental for understanding effects of water and temperature stress on transport...

Evaluation of Methods to Determine Peak Period Irrigation Water Requirements
Methods for estimating the peak period irrigation water requirement were evaluated as a component of the review of irrigation facility sizing criteria conducted for the Engineering and...

Evaluation of Basin-Furrow Irrigation Systems
The division of the total flow into basin-furrows is analyzed using both energy and momentum principles. A zero-inertia model is applied to simulate the advance phase using different infiltration...

Estimating Number and Duration of On-Times for Surge Irrigation
Research shows surge flow can achieve efficient and uniform irrigation on some soils. However, most available information focuses on computerized analysis and modeling for research purposes....

Runoff Model for Watersheds of Nonhomogeneous Characteristics
A watershed of any configuration, topography, and spatial distribution of cover, soil and channel characteristics is described as a plannar grid. Time-varying precipitation is applied...

Crop Yield Models Adapted to Irrigation Scheduling Programs
A crop yield model (CRPSM) was adapted to match the data obtained with typical irrigation scheduling programs. Daily soil water content was calculated from weather data, crop growth stage...

Water Table and Salinity Movement in a Silty Clay Soil
The movement of the water table and profile salinity in a shallow drained soil in permanent pasture overlying an artesian aquifer was observed. Soil samples were taken before and after...

Laboratory and Field Determined Seepage (abstract)
In order to obtain quick and reliable estimates of seepage, an attempt was made to establish a relationship between one or more of the properties of concrete canal lining and seepage....

Lights Out at Caribou
The Caribou powerplant restoration is one of the projects to receive an Outstanding Civil Engineering Achievement Award of Merit. On February 24, 1984 a rock slide on the ridge above the...

LFRD Bridge Design as Viewed by the Designer
The load and resistance factor design (LFRD) design concept has been resisted by some bridge engineers on the grounds that it represents a reduction of the 'factor of safety'...

The Behavior of R/C Pinned Bridge Columns under Lateral Loading
Four one-eighth scale one-way hinge details of the type used in highway bridges were tested to study the effect of combined shear and flexure caused by lateral loads. The aspect ratio...

Furrow Modeling with Variable Hydraulic Characteristics
A zero inertia furrow irrigation model was developed to run on an IBM-compatible micro-computer. The depth gradient term of the momentum equation is approximated by averaging over the...

Are Soil Moisture Accounting Models Needed for the Real Time Forecasting of River Flows?
The difficulties inherent in using conceptual rainfall-runoff models in conjunction with filtering techniques, for the real time forecasting of river flows, are reviewed. The issue of...

Effect of Rainfall Intensity Distribution on Excess Precipitation
The effect of the time distribution of rainfall intensity on the prediction of the depth of excess precipitation is evaluated. A comparison is made of the excess precipitation produced...

Seepage/Drainage Investigation Colusa County California
High groundwater in the late winter months saturates the soil profile, causing damage to both crops and soil. Sustained water logging severely damages or destroys orchards. It has generally...

USDA-Water Erosion Prediction Project (WEPP)
The USDA-Water Erosion Prediction Project (WEPP) will develop improved erosion prediction technology based on modern hydrologic and erosion science that will be process-oriented and conceptually...

Verifications and Applications of a Nonpoint Source Pollution Model
To meet the needs of the Illinois Comprehensive Monitoring and Evaluation (CM&E) project of the Rural Clean Water Program (RCWP), the Agricultural Nonpoint Source Pollution Model...

Optimization of Complex Hydrologic Models Using Random Search Methods
The primary objective of automated calibration of complex conceptual hydrologic simulation models is to find the global optimum of a specified response surface. While direct search techniques...

Local Buckling and Cyclic Behavior of Tubular Members
The effect of the local buckling is included in the cyclic analysis of tubular members. The cyclic moment-curvature curves are obtained numerically. Three types of closed form expressions...

 

 

 

 

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