Ioannis M. Dokas

Fault tree analysis and fuzzy expert systems: Early warning and emergency response of landfill operations

In this paper we argue that Early Warning Systems for engineering facilities can be developed by combining and integrating existing technologies and theories. As example, we present an efficient integration of fuzzy expert systems, fault tree analysis and Worldwide Web technologies to their application in the development of the Landfill Operation Management Advisor (LOMA), a novel early warning and emergency response system for solid waste landfill operations. The aim of LOMA is to provide assistance to landfill managers on their efforts in preventing accidents and operational problems and to help them to develop emergency response plans if these operational problems shall occur. Additional aim is to disseminate information and knowledge to the public on landfill operational problems and their adverse effects. This aim is related to solid waste organizations that have to accord with legislations which are similar to the European Unions EC Directive (2003/4/EC) on Public Access to Environmental Information. When using LOMA, the user first describes the working conditions at the landfill. Then, based on this description, LOMA informs user about the potential operational problems. Afterwards, it analyzes the operational problems in more detail and it estimates the possibility of their occurrence. Finally, it provides advice on how to prevent them and how to respond if any of them occurs. This paper thoroughly investigates LOMA development as well as its integral methodologies and validates it by outlining its performance in test cases that were performed by experts during the operation of a real landfill as well as in test cases extracted from a specially constructed database with synthetic events.

A new hybrid schema-sharing technique for multitenant applications

This paper presents a new schema-sharing technique for multitenant applications. Our approach is built on top of the Extension table method and makes use of the native XML data support to store the additional data supplied by each tenant. Our proposed technique can be used to implement multitenancy on top of a standard relational database. This paper also describes an implementation of our approach using a real-world case study aiming at improving the communication channel of information related to drinking water quality parameters used by all stakeholders involved in the water treatment process in Ireland. These include the Environmental Protection Agency, the Health Service Executive, drinking water treatment plant staff, local authorities and everybody consuming water.

Towards a Novel Early Warning Service for State Agencies: A Feasibility Study

The paper presents the results of a feasibility study in need to determine if viable, effective and reliable web based early warning service in the domain of drinking water utilities can be developed. The early warning service is intended to be used by many actors in the Republic of Ireland including water utilities managers, the Irish Environmental Protection Agency personnel and the Irish Health and Safety Executive personnel. The results of this feasibility study include an assessment of whether or not a statement of requirements for a novel early warning service can be realised using a set of existing technologies. Based on these results it is concluded that it is feasible to develop a reliable and effective web-based early warning service for drinking water utilities by adapting technologies derived from multiple disciplines including safety engineering, artificial intelligence, software and web engineering.

Knowledge Acquisition and Risk Analysis in Material Recovery Facilities by a Virtual Team

A knowledge acquisition process that has been implemented by a virtual team for the development of a knowledge based early warning system in Material Recovery Facilities (MRFs) operations will be presented. During the process, hazard and risk analysis techniques have been used extensively. In this paper emphasis will be given on the: a) activities and workflow, b) communication methods and tools used, c) the model of collaboration The result was to acquire and codify the complicated picture of the events, which are acting as triggering mechanisms to a number of operational problems, incidents and accidents during MRFs operations.