The discrete-time maximum principle : a survey and some new results

In this paper we present a review of the development of the discrete maximum principle. In the presentation, the emphasis is on a geometrical interpretation. The crucial assumptions in the theory developed are pointed out, and the attempts to overcome the limitation in the resulting theorems ore exposed. Following the review, we present a new approach to optimization of the multi-stage optimization problems called the ’ upper boundary approach ’. The classical methods of solving this problem are shown to fit smoothly into the new approach. Moreover, using this approach a number of new results have been developed, among these a new generalized version of the discrete maximum principle. The new version does not require the assumption of directional convexity.     

Free inductive K-semialgebras

We consider rational power series over an alphabet Σ with coefficients in a ordered commutative semiring K and characterize them as the free ordered semialgebras in various classes defined by the least pre-fixed point rule and its dual. The results are generalizations of Kozen’s axiomatization of regular languages.     

Knowledge base specification to automate the fluid critical point of fluids

In this paper an analytical procedure implemented to structure the knowledge required by an expert system applied for controlling a chemical process is described. The analytical approach is based on L ifecycle of Systems and on Task Model approaches. It was validated with an experimental procedure related to the determination of the critical point of pure fluids (CO₂, N₂O, SF₆) and mixtures of low concentration (CO₂-limonene). For the implementation of the control system an expert system shell (CHRONOS?) was used.     

DEVELOPMENT TOOL FOR COMPUTER VISION SYSTEMS AT PIXEL LEVEL

This paper describes a tool to aid the development of computer vision applications for pixel-level diagnosis. A conceptual framework for constructing pixel processors is described. The proposed tool is based on two domains: one deals with numerical images, named features, and the other deals with symbolic images, named classes. A reduced set of image and operator types is defined. Based on it, an object-oriented language is described. The main objects define features and classes and their associated operators, namely procedures, classifiers, and rules. All system control is goal oriented and is designed to provide symbolic images as results when a request is received from a higher level of the image understanding system. Some knowledge engineering concepts, such as certainty control and instances, are also included.     

AN APPROACH TOWARD CONSISTENCY DEGREES OF FUZZY THEORIES

In fuzzy logic-in wider, but also in narrow sense-the problem of consistency has been discussed more or less occasionally from different points of view. Up to now, however, it has usually not been taken as really important. This may be partly caused by a rather restricted understanding of what is to be meant by consistency or inconsistency in fuzzy logic in the wider sense-e.g. in fuzzy control as one of the main applicational fields of fuzzy logic.

In this paper we deal with fuzzy theories in the realm of the fuzzy logic in narrow sense. Based on the fact that usually an "interactive", r-norm based conjunction is considered together with the min-based conjunction one has in a natural way two different consistency condition. We look here at the weaker one.     

Identification of equivalent topography in an open channel flow using Lagrangian data assimilation

We present a Lagrangian data assimilation experiment in an open channel flow above a broad-crested weir. The observations consist of trajectories of particles transported by the flow and extracted from a video film, in addition to classical water level measurements. However, the presence of vertical recirculations on both sides of the weir actually conducts to the identification of an equivalent topography corresponding to the lower limit of a surface jet. In addition, results on the identification of the Manning coefficient may allow to detect the presence of bottom recirculations.     

An application-oriented,optimization-based methodology for interactive design of engineering systems†

Motivated by a control system example, a new methodology is proposed for tackling optimal design of engineering systems. This methodology emphasizes designer's intuition and man-machine interaction. It includes a classification of specifications into various types and a scaling of specification space and parameter spaces based on the designer's knowledge of the particular application. An algorithm is proposed for solving the resulting constrained ‘minimax’ optimization problem and its convergence is proved. Finally, an application-oriented user front-end is presented. The methodology discussed in this paper has been implemented in the DELIGHT system and has been successfully used in various types of applications.     

Technical Note Simulation of MEIS-II data on 5S code to quantify algal concentration in an intertidal area

An atmospheric correction algorithm due to Deschamps et al. (1981) has been applied to MEIS-II data. Some atmospheric conditions such as continental and maritime aerosol models have been used in this work. Simulation on 5S code was made with Thematic Mapper Band 4 and Spot band 3. All these pieces of the puzzle permitted the qualification of algal concentration in an intertidal area, which was the aim of this work. Continental or maritime aerosol models gave a similar result due probably to the specific area, located between land and nearshore. Apparent radiance is smaller than corrected radiance because absorption process takes place in this part of the spectrum (0.8 to 0.9μm). When apparent radiance is higher than 30 Wm^?2 sr^?1 μm^?1 algal concentration is overestimated by up to 60 per cent.