Fractal Characteristics of Fracture Roughness and Aperture Data
In this study mathematical expressions are developed for the characteristics of apertures between rough surfaces. It shown that the correlation between the opposite surfaces influences...

Nondestructive Testing Using Borehole and Surface Seismic Techniques to Evaluate Rock Mass Damage Zones
A suite of seismic tests was performed at the U12g tunnel at the Nevada Test Site. The methods include borehole (crosshole and downhole) and surface (Rayleigh wave and refraction) tests....

An Empirical Data Base for the Investigation of Earthquake-Related Changes in Crustal Hydrology
Both fracture permeability and fluid flow velocity can alter as a result of sudden strain changes associated with earthquake fault rupture. Testing the hydrological signatures of numerous...

Active Control of Structures with Soil-Structure Interaction
The objective of this paper is investigate the effect of soil flexibility on the performance of the active control system for seismic-excited buildings. By using the critical-mode control...

Ground Water: How Contaminated?
It is common knowledge that ground waters, like surface waters, are endangered by pollution from a variety of human activities. Commonsense approaches to the problem are overshadowed by...

Aquifer Restoration: Which Method?
Ground-water contamination is an increasing problem, especially in large urban areas. Toxics that seep into water supplies threaten the health of the community and it's difficult...

Wastewater Reclamation and Reuse for Malibu, California
Engineering-Science is providing consulting engineering services for the design of a sewer system and wastewater reclamation plant for the urban portion of Malibu, California. This project...

Central Valley Groundwater and Surface Water Model: A Conjunctive Use Planning Tool
A three dimensional finite element groundwater simulation model is integrated with a surface water simulation model to evaluate the conjunctive use feasibility for a specific area. The...

An Expert System for the Planning and Design of Flood Control Channels
The planning and design of flood control channels often calls for the evaluation of a unique set of physical conditions which do not lend themselves to standard designs. Consequently,...

What is a Drainage Utility?
A drainage utility is: a financing mechanism, providing a stable and dedicated funding source for surface water quality and quantity control; and a governmental entity whose mission is...

A Comparison of Accuracies of Steady Water Surface Profiles
The author compares the effect of varying boundary conditions and cross sectional spacing on one dimensional steady water surface profiles. Six streams are modeled using both the 10 and...

Numerical Solutions for Transient and Nearly Periodic Waves in Shallow Water
This paper presents a study of several numerical methods for solving transient (time-dependent) model equations for waves in shallow water by means of the method of lines. The physical...

Boundary Element Calculation of Nonlinear Wave Generation and Wave Current Interactions
A boundary element model is used to simulate the problem of nonlinear wave generation, and the interactions of wave and current. The numerical model is established based on the potential...

The Influence of the Viscosity on the Progressive Waves
In a stationary atmosphere, the free-surface progressive wave motion in a real fluid of uniform depth is analysed by using Navier-Stokes equation, and its mechanism is described in first-order...

Hydrodynamic Pressure on an Oscillating Vertical Plate
The hydrodynamic pressure on an oscillating vertical plate could be influenced by the effects of compressibility of fluids and surface waves. The compressibility is effective for higher...

The Moving Contact Line
The flow field around the moving contact line, generated by an impulsive, horizontal motion of a vertical plate, is studied numerically. The two-dimensional, unsteady Navier-Stokes equations,...

Interaction of Viscous Free-Surface Flow with Submerged Structure
The fully-transformed unsteady incompressible Navier-Stokes equations are solved numerically in a time-dependent boundary-fitted coordinate system. In addition, the complete viscous free-surface...

Time-Delayed Control of Nondispersive Continuous Systems
This paper deals with the noncollocated, time-delayed active point control of continuous systems. It considers systems of finite spatial extent which can be modelled by the undamped wave...

Optimal Control Configuration for Active Control of Structural Vibrations
An active tendon control mechanism is used to control the vibrations of a bridge-like structure. A single control force controls three modes of vibrations. Special attention is paid to...

Input-Output Discrete-Time Control of Structures
This paper outlines an approach for active control of structures based on the identification of a linear difference equation to describe the control loop and the design of a discrete-time...

 

 

 

 

Return to search