Jo Klaessens

Expert systems and analytical chemistry

Les systemes experts. Quelques exemples. Fonctionnement. Revue des systemes experts en chimie. 22 references

Digital simulation as an aid to sample scheduling in a routine laboratory for liquid chromatography

Abstract A computer model is described to aid decision-making in a routine laboratory for liquid chromatography. The managerial demand was to reduce the delay times of the samples in the laboratory despite an increasing sample input. Knowledge derived from records on the laboratory and from the experience of the laboratory staff is used to develop a simulation model of the laboratory. The model is applied to study the effects of several factors on the performance of the laboratory in order to trace the bottlenecks.

Interactive calibration by a recursive generalized standard addition method

Abstract The generalized standard addition method (GSAM) has recently been introduced for calibration to avoid matrix effects and many interferences. In GSAM, all additions and measurements precede the calculations of the K matrix (sensitivities of all analytes at all sensors_ and the analyte concentration. A recursive version of GSAM is presented here. Some new powerful properties are added to the method: (1) on-line checking of the validity of the linear model during the data acquisition stage, (2) simultaneous evaluation of the value and precision of the elements of the K matrix during the additions, and (3) access to an on-line interactive calibration, terminating the addition when the precision is within the desired limits or a deficiency in the model has been detected. The method is demonstrated for spectrophotometric measurements of copper and nickel in the presence of EDTA.

LABGEN, expert system for knowledge-based modelling of analytical laboratories : Part 2. Application to a Laboratory for Quality Control

Abstract A simulation project is described for evaluation of the performance of a section of a laboratory for quality control. The simulations are done with two recently-developed software modules. The simulation model is constructed automatically by the expert system LABGEN. Historical laboratory data stored in the information-management system are processed in a preliminary step with the programs of the module FEA. The results of the simulation project are discussed.

Problem solving by expert systems in analytical chemistry

ZusammenfassungEs ist zu erwarten, daß künstliche Intelligenz und besonders „expert systems” einen großen Einfluß auf die analytische Chemie ausüben werden. In dieser Arbeit wird ein Überblick über dieses in schneller Entwicklung befindliche Gebiet gegeben. Zunächst werden die „expert systems” im allgemeinen behandelt (Darstellung und Handhabung von Wissen, Behandlung von Unsicherheiten, Anwendung von Software zur Konstruktion der „expert systems”). Anschließend werden Anwendungen in der Chemie — speziell der analytischen Chemie — diskutiert und zukünftige Entwicklungen aufgezeigt.SummaryIt is expected that artificial intelligence and more particularly, expert systems, will have a profound effect upon analytical chemistry. This paper provides an overview of this rapidly evolving field. General aspects of expert systems are dealt with first, such as knowledge representation, knowledge manipulation, dealing with uncertainty, and the application of software tools to facilitate the construction of expert systems. The accomplishments with respect to the application of expert systems to chemistry — particularly analytical chemistry — are discussed. Future directions of the research and applications are forecasted.

Towards computer supported management of analytical laboratories

Abstract In daily practice, the laboratory management must control several complex data flows in the analytical laboratory. Computer aids to support the management are discussed. Commercially available laboratory information management systems (LIMS) apply to the flow of data about the individual samples and the subsequent test results. Additional software modules are needed to deal with data about the performance of the laboratory as an organization, to provide decision support. Two modules for this purpose are presented: FEA for processing of historical laboratory data and LABGEN for application of digital simulation by the laboratory management.

A chemometric tool for computer-aided decision making in analytical laboratory management

Abstract One of the tasks of management in analytical laboratories is the scheduling of analyses and the organization of the laboratory resources with respect to the workload. By a simulation of the laboratory operations, one can describe and eventually forecast the magnitude of the sample backlog and result delays with respect to the followed strategy to schedule samples and resources. However the design and validation of a simulation model is a lengthy and expensive task, requiring the help of a specialist in the area of operations research. In this paper an expert system is described that guides the laboratory manager through the various stages of the model design. The output of the expert system is a simulation model written in program code (SIMULA) that after compilation can be used to simulate the laboratory.