Post-MECO Propulsion System Requirements for Placement of an STS External Tank in Low Earth Orbit
This paper discusses the findings of a series of computer simulations carried out at the National Institute of Standards and Technology to investigate the requirements for powered flight...
Motion Control of Space Structures
A new area of civil engineering is emerging as we begin to establish a permanent presence in space. The new area of civil engineering is the motion control of space structures. This paper...
Effects of Initial Conditions on Large Space Structures
Effects of initial conditions of axial deformation (length) and attitude (pitch) angle have been investigated on the subsequent orbital motion, attitude (librational) motion, and axial...
Actively Controlled Optimum Structural Design
This paper deals with the investigation of the number and location of actuators and sensors on the optimum structure and control design of space structures. The optimization problem is...
Wave Propagation in Hyper-Structures
The concept of hyperelement was introduced by E. Kausel and J.M. Roesset, 1977 in connection with the derivation of the dynamic stiffness matrix for layered continuum problems involving...
The Truss-Beam and Space Technology
A method is presented herein to determine the dynamic characteristics of truss-beam systems for both planar and space structures. Results from this approach are compared with those of...
Dynamics of Composite Tubes
A displacement-based stiffness method is used to study the characteristics of dispersive wave propagation in laminated composite cylindrical tubes. It is assumed that the tube is composed...
Effect of Gravity on Dynamic Behavior of Beams
Large space structures will be needed to provide structural framework for maintaining relative positions of individual components of systems in low earth orbit. Particularly because of...
Global Problems: Implementing Mission to Planet Earth
Serious global environmental problems are facing our generation on Earth. The decrease in ozone concentrations and the greenhouse effect have implications for all life forms on the planet....
Fluid Behavior Considerations for Waste Management in Low-Gravity Environments
Design of waste recycling systems for spacecraft requires a knowledge of fluid behavior in microgravity. As gravity is reduced, phenomena usually ignored in the One-G environment of earth...
Design Considerations for a Ceramic Fabric Radiator
The design of an Advanced Ceramic Fabric (ACF) thermal management device for use in both interplanetary and near-earth space must consider several important aspects of the environment....
Application of Statistical Distribution Theory to Launch-on-Time for Space Construction Logistic Support
The Center for Space Construction (CSC) has acquired historical launch vehicle data for analyzing space launch vehicle logistic support of space construction. This analysis will include...
Columbus Generic Element Management Concept
The concept for largely autonomous onboard management of the ESA Columbus project elements relies on the automation of operational procedures. Reconfigurable items are commanded in sequence...
Predicting Watermain Breakage Rates
Recent studies on water main breakage have shown significant spatial and temporal clustering in the breakage pattern. The methodology described in the paper provides the basis for a prediction...
Rehabilitation Model for Water Distribution Systems
This paper presents an optimization model for determining the minimum cost rehabilitation and replacement of pipes in water distribution systems. The advantages of the proposed model include...
Probabilistic Basis for Managing Maintenance
The paper discusses a procedure based on component failure probabilities, consequences of failure, and risk associated with loss of system. Aging effect of structures and equipment on...
Models for Optimal Maintenance of Hydraulic Structures
Corrective maintenance includes the unscheduled repairs required to return a structure from a failed state to an operating or available state. Corrective maintenance is determined by the...
Reliability Estimation for Vertical Lift Gate at Emsworth Dam
The lift gates are composed of two horizontal trusses, two vertical girders, seven diaphragms, and two end frames. A critical element in the structural integrity of the lift gate is a...
Urban Drainage Pipe Systems: Failure Diagnosis and Rehabilitation Planning
A Task Committee on Failure Diagnosis and Rehabilitation of Urban Drainage Infrastructure has been organized by the Urban Water Resorces Committee of the Water Resourcs Planning and Management...
Remote Infrared Thermal Sensing of Sewer Voids
The question addressed by this paper is how to detect unseen problem areas in sewer systems before they give way. At present, progressive sewer administrations may use crawl crews or television...
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