Mechanical Properties of Lunar Soil and Simulants
Investigation of the physical and mechanical properties of lunar soil carried out by the USSR and the USA; both in situ and on returned samples, has resulted in considerable information...
Environmental Aspects of Lunar Helium-3 Mining
Three potential detrimental effects of lunar 3He mining have been identified; visual changes, atmospheric contamination, and solid waste disposal....
Vacuum Melting and Mechanical Testing of Simulated Lunar Glasses
Lunar silicate glasses may possess superior mechanical properties compared to terrestrial glasses because the anhydrous lunar environment should prevent hydrolytic weakening of the strong...
Mechanical Properties of Compacted Lunar Simulant Using New Vacuum Triaxial Equipment
Mechanical stress-strain-strength properties of Arizona Lunar Simulant (ALS) are investigated by using a newly developed vacuum triaxial device that allows compaction under different initial...
Extraction of Potable Water from Urine for Space Applications
A regenerative technology capable of managing water and wastewater on-board long-term manned space platforms is essential if the Bush Administration's Space Exploration Initiative (SEI)...
An Analysis of Human Performance in Simulated Partial-Gravity Environments
Three unique partial gravity test environments; parabolic flight, water immersion and a mechanical-relief device provide the environment to evaluate human locomotion, reach sweeps, and...
Solid Waste Travel Demand Model Using GIS and Simulation for Evaluating Site Impacts
This study accomplishes two objectives: (1) develops a model to forecast future household travel demands for a given solid waste site in Fairbanks, Alaska and (2) develops precursory techniques...
Continuum Model for Flows in Emergent Marsh Vegetation
Modeling of flows in tidal marshes requires modifications to the classical equations of open channel flow. In this study, the authors formulate an equivalent continuum model for tidal...
Earthquake Considerations in Earth Dam Design
In 1963, the writer was engaged by the State of California Department of Water Resources to make a study of the influence of the hazard of earthquakes on the design of embankment type...
Stochastic Dynamics of Hysteretic Systems
A frequency domain method is discussed in order to evaluate the second order statistical response of nonlinear hysteretic structures. Both shear type systems and lumped mass frames involving...
Variability Response Functions and Stochastic Field Discretization in Stochastic Finite Element Methods
Stochastic systems whose mechanical properties vary spatially are investigated in the present paper. The stochastic response variability of the systems is characterized by means of the...
Responses of Nonlinear Oscillators Excited by Non-Gaussian Pulse Processes
The estimation of the response statistics of nonlinear systems subjected to Poisson-distributed pulse processes is addressed. The procedure to be followed is based on an extension of the...
Earthquake Ground Motion Modeling with Stochastic Line Source
Principles of geophysics and stochastics are applied to develop an earthquake model, in which the earth medium is idealized as consisting of stratified elastic layers, responding to seismic...
Site-Dependence of Spatial Coherency
The spatial coherency of ground motion from nine dense arrays are analyzed to examine the site-dependence of spatial coherency. The spatial coherencies computed for arrays located on alluvium...
A Knowledge Based System with Uncertainty for the Soil
In this paper, we present the methodology that we used to develop the KBSOL Knowledge Based System for the soil. We describe the structure that contains the objects of the domain (layer,...
Low-Cycle Fatigue Prediction for Ramberg-Osgood Type Materials
The prediction of low-cycle fatigue crack growth is successfully made by an equation employing the J-integral range. This equation, originally proposed by Dowling and Begley, is analogous...
Experimental Validation of a Probabilistic Fracture Mechanics Model
A method is developed for validating a probabilistic fracture analysis code (PROFRANC). The method is based on classical statistical techniques and experimental data. It is shown that...
Pre-Test Selection of Static Force and Displacement Measurement Locations for Damage Assessment
An incomplete set of static force and displacement measurements are used for parameter identification of linear elastic structures at the element level. Measurement locations and the level...
Hydrogeotechnical Considerations for the Disposal of Oil Shale Solid Waste Material
Laboratory tests and five large scale lysimeters (7.3?3.0?3.0 m deep) have been constructed to collect information and data on hydrogeotechnical factors which affect an oil shale solid...
Case Studies of Semi-Closed Pipeline Systems for Flexible Deliveries
The semi-closed pipeline system using the best aspects of the open and the closed pipeline systems, has many applications. It is the best adapted system for use with the variable flow...
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