Regularization Methods for Identification of Structural Damage
Generally, various non-unique solutions may be obtained from ill-conditioned equations. Several methods are available to obtain a unique (minimum energy) solution to a modified and thus...
Updating Dynamic Models and Their Associated Uncertainties for Structural Systems
The problem of updating a structural model and its associated uncertainties using dynamic test data is addressed, considering uncertainties which arise from measurement noise, modeling...
Effect of Active Control on Closely Spaced Natural Frequencies
Current problems in structural control involve structures with closely spaced natural frequencies (M.J. Balas, 1983). The purpose of this paper is to show how control affects a structure...
Computer Simulation of Dry Layered Granular Flow Down an Incline Composed of Grains
Experiments show that gravity-driven dry granular flows are essentially layered for smooth spheres. This paper describes layer-to-layer interaction in the flow. Assuming two-dimensional...
Full Scale Application of Active Bracing Systems
A full scale active bracing system has been installed in a structure in Tokyo, Japan. The practical problems associated with the implementation of this system, and the corresponding solutions...
Interaction Effects in the Hybrid Control of Euler-Bernoulli Beams
The effect of viscous and Voigt damping upon the open loop response of simple continua such as Euler-Bernoulli beams is well understood. However, when attempting to control a distributed...
Recent Findings in Active Structural Control
Over the past decade, tremendous advancements have been made in the development of structural control paradigms and in the necessary supporting technologies. The fundamental paradigm that...
Structural Control Under Stochastic Seismic Loads
This paper presents a method of controlling nonlinear and hysteretic civil engineering structures subjected to stochastic earthquake ground excitations. Emphasis is placed on control of...
Inflation Instability of Cylindrical Membranes
A new procedure which investigates inflation instability of cylindrical nonlinear membranes is developed. The general characteristics of inflation instability are described. An efficient...
Nonlinear Eigensolver for Exact Vibration Analysis
Vibration analysis of structural systems is concerned with accurately predicting the free vibration modes and frequencies of the vibrating system. This analysis process involves two general...
An Expert System for Impeller Mechanical Design and Analysis
Impeller is the most critical component of centrifugal compressors. The mechanical efficiency and durability of the impeller determines the performance of the compressors. The shapes and...
Lunar Oasis
The Lunar Oasis emphasizes development toward self-sufficiency in order to reduce dependence on the Earth for resupply and to enable expansion utilizing indigenous resources. The Oasis...
A Horizontal Inflatable Habitat for SEI
The inflatable habitat described in this paper is a horizontally-oriented cylindrical pneumatic structure. It is part of NASA's ongoing effort to study inflatables as alternative habitats...
Cables and Cranes for a Flexible Lunar Transportation System
This paper will discuss the results of preliminary research on a cable-based transportation system for the moon. The paper will address the principles of cableway design and will present...
Performance-Based Evaluation of Lunar Base Construction Equipment and Methods
Existing literature regarding the selection of lunar base construction equipment and methods is heavily dependent upon qualitative measures for evaluation of equipment concepts. Selection...
The Application of Open System Architecture to Planetary Surface Systems
This paper investigates the issues that future planet surface activities must confront, defines the basic concepts that provide the basis for establishing an Open System Architecture,...
Chemical Analysis in Space Exploration: A Lunar-based Chemical Analysis Laboratory (LBCAL)
Many questions need to be answered before humans can be supported for extended periods in space - an environment inimical to terrestrial life. While some questions of a physiological nature...
A Modified Sulfate Process to Lunar Oxygen
A modified sulfate process which produces oxygen from iron oxide-bearing minerals in lunar soil is under development. Reaction rates of ilmenite in varying strength sulfuric acid have...
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...
Design Concepts for a Lunar Electric Power System
This paper discusses the results of ongoing research and the evaluation of various concepts for transmission, distribution and utilization of electric power for a lunar liquid oxygen plant....
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