Innovative Computing Techniques for Development of an Integrated Computer Control System

Abstract

Over the past decade there has been a shift in emphasis from design and construction of wastewater treatment facilities to operation. Poor plant performance, high costs and damage to the environment have resulted from operational problems. Wastewater treatment consists of a complex sequence of inter-dependent biological, physical and chemical processes subject to time-varying hydraulic and organic load conditions. Wastewater treatment process operation and control is a knowledge intensive task. Research on improving operation and control has centred on identifying important mechanisms responsible for observed behaviour and modelling both the process and optimum ways of operating the process. These models have served as useful tools for improving operation and control. Many different approaches have been used, including deterministic modelling, stochastic modelling and, more recently, linguistic modelling. Complex mathematical models of wastewater treatment processes consisting of large numbers of non-linear differential equations can be constructed using tools such as the General Purpose Simulator (GPS) and, given appropriate data, model parameters can be evaluated and updated using existing optimization routines. Object oriented programming (OOP) and a model based reasoning (MBR) approach provides a useful framework for development of deep-knowledge expert systems (ES). Data-driven modelling methods, including both time series analysis and artificial neural network (ANN) techniques, can also be employed to make maximum use of information contained in process data. Each of these model types is a necessary component of a computer system for operational control of wastewater treatment but, in isolation, none are sufficient for making the system robust. An integrated environment for combining these techniques has been developed for this purpose and the basis for its development is described.

Control algorithms of infiltration water intake under uncertainty

“…The main source of uncertainty at the water intake stage are hydrologic and hydro-geologic processes occurring in the water intakes. In such case one must elaborate specialized control algorithms realizing their function in uncertain and incomplete data conditions about controlled processes [4,7]. …”

“…On the basis of the results the synthesis of control scenario for specified states of the system becomes possible. Moreover, elaborating the computer operators' decision aid turns out to be of a significant meaning, too [7,9].…”

Modelling, Simulation and Control of Urban Wastewater Systems

“…Modules for chlorination, filtration and chemical phosphorus removal are under development. GPS-X is applied to many large-scale treatment plants in several countries (Patry and Barnett, 1992).…”

A Distributed Control System Based on Agent Architecture for Wastewater Treatment

“…Moreover, knowledge-based systems (KBS) have been widely used to implement control systems at treatment plants. Most of the systems reported are off-line KBS designed for diagnosis and advising tools for operators (Gall and Patry, 1989;Barnett et al, 1992;Patry and Barnett, 1992;Ozgur and Stenstrom, 1994). Some KBS have been designed with the main purpose of on-line supervision (Verheijen et al, 1997), although no real-time supervisor control has been used.…”