Estimation of Wind Fields for Coastal Modeling
Wind is an essential driving force for waves, circulation, and storm surge in coastal and estuarine areas. As with other horizontally 2-dimensional models, Corps of Engineers' (CE) numerical...

A Semi-Implicit Finite Difference Model for Three-Dimensional Tidal Circulation
A semi-implicit finite difference formulation for the numerical solution of three-dimensional tidal circulation is presented. The governing equations are the three-dimensional Reynolds...

Modelling of Coastal Circulation in Singapore Waters—A Hybrid Approach
A hybrid modelling technique which involves the integration of numerical and physical models has been used to study tide induced circulation in Singapore coastal waters. The modelling...

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...

Approximation of Convective Processes by Cyclic AOI Methods
Convective or advective processes play a role in many models for civil engineering applications. For example in transport equations, in hydrodynamic equations or wave energy equations....

Generating Detailed Emissions Forecasts Using Regional Transportation Models: Current Capabilities and Issues
Mobile source emission estimates have long been calculated using composite emission factors (expressed as grams of emissions per mile) and estimates of vehicle-miles travelled. Techniques...

Characteristics of MOBILE4 and EMFAC7E Models
Several recent studies (e.g., Lawson et al., 1990; Ingalls, 1989) have indicated that the EPA and ARB vehicle emission factor models MOBILE4 and EMFAC7E underpredict in-use vehicle emission...

Maximum and Minimum Storage Trajectories That Meet Specific Risk Levels
One of Hydro-Quebec concerns is to operate its installations so as to satisfy the operating constraints. This paper describes a mathematical tool that enables the utility company to state...

Reliability Analysis of Uncertain Systems Under Random Loadings
This study considers the reliability assessment of uncertain systems under random loadings. The fast integration method (Wen and Chen, 1987) in conjunction with a second order asymptotic...

A Coordinate Reduction Technique With Mass Correction for Dynamic Analysis of Structural Systems
A more accurate technique which can be applied for reducing the order of system matrices when employing the finite element method (FEM) is presented. Unlike traditional reduction techniques,...

Quantifying Uncertainty in Site Characterization
The uncertainties in determining the true geologic conditions at the proposed high-level nuclear waste repository at Yucca Mountain, Nevada needed to be determined as part of the Exploratory...

Sensitivity Evaluation of Simulation Methods for Reliability Assessment
Commonly used reliability assessment methods include the first-order methods, second-order methods, and Monte Carlo simulation methods with or without variance reduction techniques. The...

A Mathematical Tool Set for SORM Reliability Methods
FORM and SORM methods are used for approximating failure probabilities. Here an overview of the main mathematical results of SORM methods is given: Classification of asymptotic behavior,...

Earthquake Ground Motion Modeling with Stochastic Line Source
Principles of geophysics and stochastics are applied to develop an earthquake model, in which the earth medium is idealized as consisting of stratified elastic layers, responding to seismic...

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...

Finite Element Dynamic Reliability Analysis with Condensation
This paper presents the use of matrix condensation in stochastic finite element-based reliability analysis of structures subjected to dynamic loading, in the context of modal superposition....

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...

A New Probabilistic Model for the Fracture Toughness of Concrete
Scatter of strength and toughness parameters as well as scale effect are often observed in brittle materials such as concrete. The recently developed Crack Diffusion Model is utilized....

Stochastic Modeling of Short Fiber Reinforced Composites—A Review
Since the early 1960's, an extensive research and development has been carried out with fiber reinforced cements and concretes. Modeling of such heterogeneous material is still in the...

2-D Evaporation and Root Extraction in an FEM
Two-dimensional processes of soil evaporation and moisture extraction by plant roots (horizontal and vertical) were incorporated into a saturated/unsaturated finite element model (UNSAT2)...

 

 

 

 

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