Response of Space Structures Under Sudden Local Damage
Damages to space structures can come from such adverse events as impact by foreign objects, docking, drastic temperature changes, and exposure to radiation and charged particles. This...
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...
Regolith Dynamics
Due to the differences of the gravitational accelerations of the Earth and Lunar environments, geotechnical engineering must be applied differently in the two environments. This study...
Principles of Control for Robotic Excavation
Excavation can be considered one of the most unstructured problems in the construction environment. On one hand, many technologies have been developed in the past to build shelters using...
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,...
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...
Preliminary Investigation of a Lunar 16 Meter Optical Telescope
The results of a year-long effort to develop a design concept for the structure of a 16 meter lunar optical telescope are presented. Various mounting configurations and mirror configurations...
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...
3-D Modelling of Heat Discharge from Ul-Jin Power Plant into Coastal Waters of Korea East Sea
This study focuses on the problems of simulating the coastal currents and their effect on the distribution of heated cooling water from the Ul-Jin power plant into coastal waters of Korea...
A Modified Adjoint Method for Inverse Eddy Viscosity Estimation for Use in Coastal Circulation Models
The adjoint method is used to develop an objective analysis technique for estimating the vertical eddy viscosity used in three dimensional oceanic models. A cost functional which consists...
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...
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...
Optimal Flood Warning Threshold: A Case Study in Connellsville, Pennsylvania
A methodology for selecting an optimal flood-warning threshold has been developed by Haimes et al. (1990). The probabilistic evaluation of a forecast system coupled with a stochastic dynamic...
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....
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...
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