INTRODUCTION ................................................................................ 882 I. HYRAULIC FRACTURING POSES ENVIRONMENTAL RISKS TO DRINKING WATER SUPPLIES ........................... 885 II. HYDRAULIC FRACTURING REGULATION IN THE UNITED STATES ..................................................................... 887 A. THE SAFE DRINKING WATER ACT AND THE EPA’S TIMID IMPLEMENT...

This paper describes the implementation of a real-time hydraulic model of a water distribution system in Singapore. This on-line system is based on the Integration of real-time hydraulic data with hydraulic computer simulation models and statistical prediction tools. To facilitate this implementation, a network of wireless sensor nodes continuously sample hydraulic data such as pressure and flo...

In order to study the numerical control (NC) servo press hydraulic control system and its control algorithm. The numerical control servo press performance and control principle of hydraulic control system are analyzed. According to the flow equation of the hydraulic control valve, hydraulic cylinder flow continuity equation and the force balance equation of the hydraulic cylinder with load pres...

Abstract In general two basic methods are used for controlling the velocity of a hydraulic cylinder. First by an axial variable-displacement pump for controls flow to the cylinder. This configuration is commonly known as a hydrostatic transmission. Second by proportional valve powered by a constant-pressure source, such as a pressure compensated pump, drives the hydraulic cylinder. In this stud...

1 Hans Kleine Büning, Benno Stein ABSTRACT Configuration is a process of creating complex systems out of a finite set of predefined objects. This process may enclose the selection, the assemblage and the adaptation of these objects. In this paper we want to describe how the configuration of hydraulic plants can be supported. A hydraulic plant is a complex system that consists of electronic, mec...

Editorial Board Eric Britton, Managing Director, EcoPlan International, The Centre for Technology & Systems Stud ies, 10 rue Joseph Bara, 75006 Paris, France. Paul Tra nter , Senior Lecturer, School of Geography & Oceanography, Un iversity College, Australian Defence Force Academy, Canberra ACT 2600, Australia. John Ho we, Professor of Transportation En gineering & Head of Infrastructural En gi...

A lysimeter station has been set up by AMRA for the study of the reactive transport of contaminants in soil at the field-scale. It consists of eight lysimeters that can operate individually and simultaneously. Each lysimeter is a steel cylinder (diameter 1.14m, height 2m) filled with an undisturbed soil monolith, whose upper surface is directly exposed to the external environmental agents. A se...

Recent increases in the use of hydraulic fracturing (HF) to aid extraction of oil and gas from black shales have raised concerns regarding potential environmental effects associated with predictions of upward migration of HF fluid and brine. Some recent studies have suggested that such upward migration can be large and that timescales for migration can be as short as a few years. In this articl...

Generic, ready-to-use preliminary design methodologies for aircraft utility systems, made available by means of a Computer Aided Engineering (CAE) tool do not exist. An attempt is made to apply principles used in preliminary aircraft design to preliminary design of utility systems. This is demonstrated for the flight control and hydraulic system. The Computer-Aided Engineering tool consists of ...