Bulk Stomatal Resistance in Operational Estimates of Evapotranspiration
General relationships for estimating canopy or bulk stomatal resistance and aerodynamic resistances of grass and alfalfa reference crops for use in the Penman-J.L. Monteith equation are...
Stable Channels with Loose Boundary
Recently, G. Parker suggested that the lateral transport of downstream momentum due to Reynolds stresses should be included in the momentum balance used to calculate the boundary shear...
Near-Bed Sediment Concentration in Non-Uniform Flows Over Gravel Beds
The calculation of near-bed sediment concentration is formulated in terms of equations governing the dispersion of heavy particles in non-uniform turbulent shear flows over stable gravel...
Analytical and Numerical Modeling at High Sediment Concentrations
Methods for classifying sediment-water mixtures according to material concentration and rheologic properties are discussed. Results from laboratory and field measurements show that bed...
Entrainment of Bed Sediment by Density Underflows
The erosion caused by a density-driven underflow has been studied experimentally. The observations indicate that a strong density current can entrain substantial amounts of bed sediment....
Ultimate Sediment Concentration
The sediment rating curve is used to relate sediment discharge to water discharge, under steady equilibrium flow conditions. The slope of the sediment rating curve is a measure of the...
Effectiveness of Spur Dike Notching
The most widely used technique of ameliorating the environmental effects of river-training works has been to construct notches in spur dikes (or to allow notches to remain in damaged dikes)...
Snow-Melt Triggered Debris Flows Affecting Utah's Megalopolis
During the abnormally wet years of 1983 and 1984, debris flows were triggered late in spring on the west flank of the Wasatch Mountains and elsewhere in Central Utah. These debris flows...
Analysis of Onsite Measurements of Scour at Piers
Existing onsite measurements of local scour at bridge piers were assembled and analyzed to obtain an equation that predicts the expected maximum depth of local scour at a bridge pier....
Prediction of Scour Depth Under Armoring Conditions
A simple procedure is proposed to compute scour depth on an alluvial bed having graded materials under flow conditions which produce armor layer at the bed surface. The procedure is based...
The Effects of Sediment Transportation Changes on Aquatic Habitat
Sediments are a natural part of the riverine and estuarine environment. However, if the sediment load changes or bed sediment type occur, direct and sometimes detrimental and sometimes...
Estimation of Uplift Pressure in Cracks in Concrete Gravity Dams
This paper presents an analytical solution to predict uplift pressures in cracks in concrete gravity dams. It is shown that drainage systems are effective in reducing such pressures....
Lunar Resources: What is Known and Expected
The lunar regolith is the source of a number of basic materials which can be utilized in lunar construction. These materials include those which are obtained directly from the regolith...
Environmental Considerations for Lunar Base Engineering
Currently a large number of conceptual designs are being offered for the lunar base involving various types of structural materials and equipment for construction or resource recovery....
Generation of Native FE in Lunar Soil
Electron Spin Resonance (ESR) studies on lunar samples produced some unexpected results which led to recognition of the presence of abundant single-domain Feo...
Hot Pressing of Lunar Soil and Qualification for Manned Applications
Lunar soil may be fabricated into useful building materials analogous to those used for masonry, concrete and ceramic pipe applications on earth. The process has been analyzed theoretically...
Sintering Lunar Simulants Using 2.45 GHz Radiation
In situ sintering of lunar regolith may be useful for slope stabilization, dust control, and other applications around a lunar base. Having a knowledge of the mechanical properties of...
Carbonyl Extraction of Lunar and Asteroidal Metals
The century-old Mond process for carbonyl extraction of metals from ore shows great promise as an efficient, low energy scheme for producing high-purity Fe, Ni, Cr, Mn, and Co from lunar...
Use of Alkali Activation of Alumino-Silicates to Form Binders from Lunar Soil
The establishment of a permanently manned lunar base requires construction materials which can withstand the lunar environment and can be obtained from locally available lunar materials....
Cement-Based Materials for Planetary Facilities
The use of concrete and other materials based on a cementitious matrix is evaluated for the construction of planetary base facilities. Consideration is given to the most recent developments...
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