Materials and Structures Synergistic with In-Space Materials Utilization
The objective of this paper is to clearly demonstrate the significant advances made in recent months toward actual hardware realizations of various concepts for the utilization of in-space...
Mars Mission Designs: Comparing the Near Term Options
The benefits to be derived from manufacturing chemical rocket propellants from native resources on the Martlan surface are so great that it will almost certainly be a component of any...
Power Sources for Lunar Bases
Working and living on the Moon requires artificial power sources both to operate equipment and to maintain life. This paper briefly surveys the power sources designed or proposed to support...
Lunar Mining?Surface vs. in Situ?A Comparative Study
Surface mining and in situ mining are briefly reviewed and compared. It is verified that the inherent advantages of in situ mining over surface ruining point out that in situ mining should...
Telerobotic Field Geologist: Preliminary Results of a Feasibility Study
We conducted three laboratory studies to explore the feasibility of developing a telerobot to perform planetary field geology. In all, 72 college students attempted to match each of 15...
Very Low Frequency Radio Astronomy from Lunar Orbit
This paper discusses the use of very low frequency aperture synthesis as a probe of astrophysical phenomena. Specifically, the science achievable with the Lunar Observer Radio Astronomy...
Laboratory Evaluation of Footings for Lunar Telescopes
Presented here are the results of laboratory experiments with different footing shapes for lunar telescopes. These experiments used a variety of soils including some to simulate regolith...
Plot-scale Field Experiment of Surface Hydrologic Processes with EOS Implications
Plot-scale hydrologic field studies were initiated at NASA Marshall Space Flight Center to a) investigate the spatial and temporal variability of surface and subsurface hydrologic processes,...
In Situ Recovery of Water from Dormant Comet Cores & CI Carbonaceous Chondrites
Water and volatiles may be produced by drill holes into dormant comet cores or class CI or CM asteroids. This is modeled after in-situ mining as in the Frasch process sulfur mines of the...
Field Verification of a Wave-Induced Current Model
A unique data set of nearshore waves and current measurements over a bar-trough bathymetry was collected during a field experiment at Duck, NC, in October 1990. These high-quality data...
Nondestructive Testing of Concrete Elements and Structures
Quality of a concrete structure depends on good construction practice. On the other hand, continuous repair and maintenance preserve the quality of construction. Nondestructive evaluation...
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...
Laboratory Tests of Modal Emissions and Off-Cycle Corrections to FTP-75
The modeling of emissions from on-road mobile sources is an on-going process. Two broad topics which are currently under study are the evaluation of driving cycles and the development...
Implementing Uncertainty Treatment in AI Development Environment
The seismic vulnerability of existing masonry buildings is investigated by an expert system prototype. Field inspectors have to provide answers which can be of a Boolean, fuzzy or probabilistic...
Fuzzy Measures in the Knowledge Based Diagnosis of Seismic Vulnerability of Masonry Buildings
Rules based expert systems and fuzzy logic have been employed to increase the speed and the reliability of the survey of masonry buildings, to forecast their seismic vulnerability....
Structural Reliability of Seismic Isolation System
Seismic reliability analysis of isolated structure is conducted. In this study focused on are bearing capacity of isolation layer considering strength randomness of isolation bearings...
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...
Probabilistic Evaluation of Redundancy of Bridge Structures
Redundancy of bridge structures and methods to evaluate redundancy are reviewed in this paper. A method to measure redundancy based on the existing theories of probability as related to...
Development of a Limit-State Seismic Code for Bridges
The catastrophic collapse of the Cypress Street Viaduct during the Loma Prieta earthquake of October 17, 1989 and the loss of spans in both the Struve Slough Bridge and the San Francisco-Oakland...
Reliability Model for Bridge Columns under Seismic Loads
This paper develops a model for the analysis of the reliability of bridge columns under earthquake loads. Probability of failure is defined as the probability that the displacement ductility...
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