An approach to integrating intelligentdiagnostics and supervision of machine tools

Arguments are presented for the necessity of integrating diagnostics and supervision in technological machines. An example of integrated diagnostics and supervision of the machine tool main drive, based on an expert system and neural network, is shown. Problems of intelligent thermal displacement supervision and questions related to practical supervision of machining centres are presented.     

Structure of differential-algebraic equations for control problems in mechanics

A problem of control of a mechanical system in a partly specified motion is studied. It is shown that the structure of differential-algebraic equations (DAEs) describing the problem may essentially differ from the structure of governing equations for a constrained mechanical system. The control forces chosen to realize the program constraints may have arbitrary directions with respect to the constraint manifold, and, in the extreme, they may be tangent. Thus, the index of the original DAEs of the problem may exceed three and a special approach to the problem solution has to be undertaken. Such an approach is proposed; a systematic formulation is given for the transformation of the DAEs into index-one DAEs or ODEs. Criteria for solvability of the problem are included.     

Stabilization of linear multivariable constant delay-differential systems

The article presents the iterative method of stabilizing control signal selection in the form of the state-feedback of a multivariable linear time-invariant plant with delays. The proposed method is based on the consecutive assignment of the single system eigenvalues λ_j so that its stabilizability will be preserved for a given iteration step and the assigned eigenvalues will not be changed, even though a dynamical element identified by the matrix K_j(z) (where z is an elementary delay operator) is placed into the state feedback. To illustrate the abovementioned method, a simplified example is given.     

Computational algorithm for input-signal optimization in distributed-parameter systems identification

This paper deals with the problem of optimum choice of testing signals for identification in linear distributed-parameter systems. It is based on earlier theoretical results of one of the authors, which are extended here by investigating the structure of the optimal input signal. These investigations allow the proposal of an efficient computational algorithm. Its convergence is proved and the convergence rate is verified by numerical studies     

ON PRAXIOLOGY OF PREPARATORY ACTIONS

Praxiology, the so-called science of efficient action, is a French-Polish contribution to systemism. The French chapter of praxiology belongs to its prehistory, while the classical praxiology of the 20th century has been originated and developed by Polish philospher Tadeusz Kotarbinski (1886-1981), a member of well known Lvov-Warsaw school of philosophy and logic. The paper is dedicated to the 100th anniversary of Tadeusz Kotarbithski's birthday.

In the article a new chapter of praxiological studies, i.e., science of efficient action preparation, called preparatorics, is introduced. The sub-discipline is considered as praxiological response to the growing importance of pre-actions in general and meta-actions, like decision-making, designing, planning, and other practical problem solving activities, in particular.     

Inductive Learning in Civil Engineering: Rough Sets Approach

The paper discusses several potential civil engineering applications of inductive systems based on the theory of rough sets. This theory is discussed briefly. An inductive system is proposed for applications in knowledge acquisition for expert systems, for problem-solving, shallow modeling, learning about different domains, and in learning expert systems.     

DEVELOPMENT OF A HYBRID MODEL PREDICTING THE MOUTHFEEL OF YOGURT

Texture perception and mouthfeel are sensory variables that still need further clarification. A reliable method to describe mouthfeel quantitatively by means of physicochemical measurements is missing so far. The current study focuses on a better understanding of the texture perception of yogurt. The final aim of the study consists of the development of a novel hybrid model, which is able to predict mouthfeel sensations objectively. For this purpose, cognitive methods are used in order to merge underlying data pools with respect to process parameters and the composition of dry matter content. These employed data pools result from rheological characterizations as well as sensory analyses of yogurt and from numerical simulations of fluid flow in a simplified anatomical model of the human mouth. This paper introduces the exact procedure of the study. Furthermore, the methods for generating the underlying data pools are described, and the results are presented.

PRACTICAL APPLICATIONS

The in-mouth model is based on fluid mechanics and enables the investigation of human consumption processes that accompany fluid flow in the oral cavity. Here, it reveals mechanical stimuli, which occur because of the movement of the tongue during deglutition. Therewith, the ongoing study affords a new approach to understand factors influencing the popularity and consumer acceptance of several products as their behavior in the mouth can be clarified. Having the software development completed, this innovation represents a great potential for the food industry. While supporting future sensory analyses, it both shortens development cycles of new products and optimizes existing foodstuff.     

Microstructural analysis of iron aluminide formed by self-propagating high-temperature synthesis mechanism in aluminium matrix composite

An aluminium matrix composite with iron aluminide formed in situ as a result of self‐propagated high‐temperature synthesis was examined. The structural characteristics of the reinforcement investigated by scanning electron microscopy and transmission electron microscopy methods are presented. Iron aluminide particles with a very fine grain size and of two shapes, cubic and needle‐like, were observed. No differences in their phase composition were found by the selective electron diffraction pattern method. The composite reinforcement formed in the early stage of self‐propagating high‐temperature synthesis consisted only of the Al₃Fe phase.