Informatica

Stochastic programming problems with simple recourse belong to problems depending on a random element only through the corresponding probability measure. Consequently, this probability measure can be treated as a parameter of the problem.

A development of algorithms and writing of programs are considered as closely related but not identical parts of computer programming. Some differences between them are important for learning of computer programming, in particular, in distance learning. These differences are identified and discussed from the pedagogical point of view. The arguments for the selection of pedagogical based and cost-effective delivery modes in the case of distance learning are investigated. Practical examples supporting theoretical arguments are given on the activities of Lithuanian schools.

A multiple criteria decision support system has been developed and implemented on the personal computer. Three interactive methods of increasing complexity are realized. The main applications of the system were in the scope of decisions on the best energy development strategy for Lithuania.

Despite the vast and rich panorama of hypertext research, to date there are still no clear definitions of what hypertext really is. Classical references describe the concept “hypertext” as a non-linear way of thinking, reading, and accessing the information which is best done on the computer screen. This paper shows the present situation where hypertext is seen as the interaction between the learner and an information source; it raises questions about how information should be organised so as to promote better learning. Due to the fact that the present empirical results still show no consensus among hypertext researchers about the different representations of educational hypertexts; this paper will bring together three perspectives, in particular traditional, pedagogical and psychological points of view, in order to obtain a coherent view of the current situation in hypertext research. The traditional perspective will outline two main problems that seem endemic to hypertext: problems of navigation and cognitive overload. The pedagogical perspective will summarise the main ideas of three possible theoretical justifications of existing educational hypertexts: the ideas of concept mapping, cognitive flexibility theory, and semantic networking. The psychological perspective will evaluate hypertext from the perspective of human factors (or ergonomics).

A possible interpretation, in terms of fuzzy classification models (fuzzy classifiers), of one of the general principles of choosing a scientific theory – a consistency principle – is considered. A concept of a stability measure of unsupervised fuzzy classifiers is introduced. A general scheme of computing the above measure is proposed. A concrete algorithm for implementing the general scheme and examples of its application are given.

A possible interpretation, in terms of fuzzy classification models (fuzzy classifiers), of one of the general principles of choosing a scientific theory – a consistency principle – is considered. Supervised self-guessing fuzzy classifiers are determined. A theorem on character of restrictions induced on a set of supervised fuzzy classifiers by a self-guessing requirement is proved. Feasible alternatives of using the self-guessing property while constructing supervised fuzzy classifiers are analyzed.

The existing decomposition technology of cooperative developments of multidiscipline technical complexes (MTC) don't provide global optimality die to the imposiolity of solving the problem of developing principles of local project solutions made by a dreat number of specialists of different branches of science. This problem is supposed to be solved by means of controlling of real-time of MTC space structural-parametric synthesis in terms of hierarchically organized variety of assumed scheme-structural and technological solutions. The basis algorithm: 1) realization method for a variety of possible structural organizations of a complex technical system in the form of a network analyzer; 2) method combining synthesis combinatorial operations and parametric operations in search for short routes of the developed network analyzer.

The configuration and essential features of the Computer-Aided Test Program Design System (CATPDS) which generates test programs in an adapted ATLAS subset for analogue units under test are discussed. The requirements for that class of systems are formulated and how to meet these requirements is proposed. The formal model to describe the process of an interactive test program generation and incremental translation is presented.

An analytical equation for a generalization error of minimum empirical error classifier is derived for a case when true classes are spherically Gaussian. It is compared with the generalization error of a mean squared error classifier – a standard Fisher linear discriminant function. In a case of spherically distributed classes the generalization error depends on a distance between the classes and a number of training samples. It depends on an intrinsic dimensionality of a data only via initialization of a weight vector. If initialization is successful the dimensionality does not effect the generalization error. It is concluded advantageous conditions to use artificial neural nets are to classify patterns in a changing environment, when intrinsic dimensionality of the data is low or when the number of training sample vectors is really large.