Roof Management Alternatives for Aging Launch Infrastructure
This paper describes a Roof Management System approach to better cope with aging and deteriorating infrastructure support facilities at our national spaceports. It describes facility conditions...

Rocket Fuel to Earth Orbits from Near-Earth Asteroids and Comets
The analysis describes an architecture to bring 10,000 tons units of rocket fuel ore, propellant and construction mass back to low Earth orbit from newly discovered near-Earth comets or...

Metallized Microballoon EMI Shielding Materials
The number of applications requiring shielding against electro-magnetic interference (EMI) is growing. Materials that are lightweight, and formable need to be developed for shielding against...

Model Development for Operational Use to Help Spill Combating and Sea Rescue
Based on twenty years' experience on flow velocity measurements, transport experiments and numerical modeling the three-dimensional (3D) models of water currents, transport and water quality...

A Shell Approach to Modeling Oil Spill Trajectory and Fate and Search and Rescue Operations
A shell approach is employed to facilitate the application of an oil spill trajectory and fate and search and rescue model to a wide variety of geographic areas. In this strategy the model...

Fiber: Good For the Concrete Diet?
Fiber reinforcement of concrete has many advantages, but after thirty years of research those benefits have most often been seen in a laboratory. Some materials, such as synthetic fibers,...

Better Cover-Ups
Designing the final cover for a solid waste landfill or remediation site is often trickier than designing its lining because a cover will undergo more unpredictable stress and distress...

Adding Up Admixtures
The importance of preventive maintenance and lifecycle costs has put added emphasis on concrete performance. For many specifiers, chemical admixtures, added to concrete at the batch plant,...

Apollo 11 Ilmenite Revisited
Various investigations have shown (1) that lunar regoliths are extremely complex materials, (2) that ilmenite is a minor component (8 to 10%) of high-Ti regoliths, and (3) that most of...

Housing?Economic Standard
House project with simplistic spatial concept (integrated system) in order to facilitate construction and further expansions with the same architectural design. The design allows for the...

Methodology for Evaluating Dredged Material Alternatives Using Risk-Cost Analysis Under Uncertainty
A methodology and a case example was presented at the 1989 Conference on Risk-Based Decision Making in Water Resources, Santa Barbara, to perform risk-cost analysis for dredged material...

Linearisation and Offshore Fatigue Reliability
In determining the force effects due to wave action on offshore structures it is conventional to use an equivalent linearisation to convert wave velocities to forces via Morison's equation....

Probability Model of Load Exceedances under Cyclic Loadings
A probability model for nonlinear load exceedances subjected to a Poisson process with reversible cyclic load pulses was developed and is presented in this paper. A reversible cyclic load...

Inspection Planning for Surface Fatigue Cracks
A reliability based method for planning of inspections to detect surface fatigue cracks is presented. Cracks are described as semi-elliptical surface cracks. The conditions governing fatigue...

Some Remarks on BK-Models for Fatigue Crack Growth
The choice of a model parameter for concentrating the entire uncertainties of a constant load amplitude fatigue crack growth process is shown to be sufficient when reproducing the first...

A Fatigue Reliability Model for Railway Bridges
A fatigue reliability model is described for safety evaluation of steel railway bridges. The model is a function of six independent random variables and can accommodate different types...

A Stochastic Approach to the Fatigue Reliability
In this paper, the stochastic approach, which combines the mixed boundary integral equation method (Lua et al (1992a)) with the First Order Reliability Method (FORM), is applied to study...

Some Modeling and Analysis Techniques for Wave Propagation in Random Media
Some mathematical modeling techniques for the problem of wave propagation in randomly imperfect periodic medium are reviewed: multiscale formulation and random evolution modeling. These...

Wavefront Propagation in Random Granular Media
A very brief account is given of a stochastic method developed for analysis of transient waves propagating in one-dimensional random granular-type media. The method is suited to study...

Fatigue Strength of Welded Joints Under Broadband Loadings
Twelve welded high strength steel cruciform specimens were tested under stochastic loadings to determine the influence on fatigue life of the bandwidth of the loading process. Constant...

 

 

 

 

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