CitationDownload as .RIS
Emerald Group Publishing Limited
Copyright © 2009, Emerald Group Publishing Limited
Article Type: Guest editorial From: Kybernetes, Volume 38, Issue 7/8
According to a well-grounded tradition, Kybernetes offers the possibility to publish selected papers of World Organisation of Systems and Cybernetics (WOSC) Congresses. The recent 14th International Congress of Cybernetics and Systems of the WOSC held in Wroclaw, Poland in September 2008 was hosted by the Institute of Information Science and Engineering at Wroclaw University of Technology. This special issue being a compilation of a good range of selected papers is one of the announced post-congress publications.
The congress in Wroclaw provided an open forum in which researchers coming from different scientific disciplines and research areas could discuss and share their experience regarding methodological approaches and application areas of cybernetics and systems. The contributions received from more than 200 authors span a broad range of methodological approaches such as:
information and communication systems;
manufacturing and transportation systems; and
education and history of cybernetics and systems.
The papers presented in this issue can be split into five parts which appropriately reflect the main streams represented in the congress presentations, dealing, in majority, with theoretical aspects of cybernetics and systems as well as with their applications in engineering systems of different nature. In total, 29 papers have been selected and the authors have been asked to prepare extended versions of their papers presented during the congress and included in the congress proceedings. Not all selected authors join this issue. The others have reworked their papers presenting updated and revised versions according to comments given by reviewers. Among these papers, there are all contributions delivered by the Congress Plenary Speakers: Professor Tadeusz Kaczorek, Professor Nicolae Bulz and Professor Sifeng Liu as well as by all recipients of Kybernetes Research Awards (for details see Appendix 4 of “Conference reports” published in Kybernetes, Vol. 38 Nos 1/2, 2009, p. 264).
The first part contains contributions concerning systems theory and its application to control systems. It starts with the work of Tadeusz Kaczorek which introduces a new class of fractional positive continuous- and discrete-time linear systems. Solutions to the state equations of the fractional systems are given and necessary as well as sufficient conditions are established for the internal and external positivity and of the reachability and controllability to zero of the fractional systems. The next paper of Łukasz Sajewski concerns a new class of singular hybrid linear systems. Solutions of corresponding state equations and their properties are presented and discussed. The next two papers deal with different aspects of control theory. Aleksandra Nowacka-Leverton and Andrzej Bartoszewicz consider a new sliding mode control algorithm for the second-order dynamic system subject to input signal and velocity constraints. The solution algorithm proposed ensures insensitivity of the controlled system with respect to external disturbance and model uncertainty as well as guarantees fast tracking error convergence to zero without overshoots or oscillations. The purpose of Pavel Pakshin and Sergey Soloviev’s paper is to perform a parametric description of all static output feedback stabilizing controllers for linear stochastic discrete-time systems with Markovian switching systems as well as to use the results for the stabilization of the systems. The algorithms obtained are based on a computationally efficient non-iterative technique. An aspect of symmetry and asymmetry in general systems is addressed in the papers by Nicolae Bulz, Eufrosina Otlacan and Mieczyslaw Jessa. Nicolae Bulz’s comprehensive work gives profound considerations on systemic and cybernetic knowingness: relating according to classical as well as original concepts of (a)symmetry and subtleness. The presentation is illustrated by different examples concerning systems of different nature, e.g. information, knowledge, economic and social ones. Different aspects of the role of symmetry underlines Eufrosina Otlacan in her work where a pair of conjugate systems is investigated, their differential models are considered, and checked is the property of what kind of symmetry or harmony is established in the common evolution of systems under consideration. New properties of continuous- and discrete-time dynamic systems are demonstrated by Mieczyslaw Jessa. The attention is paid to the differences between both systems, and the conclusion is justified that many discrete-time systems cannot be embedded into continuous ones. The controllability of systems described by nonlinear hyperbolic equations is investigated by Marek Majewski and Dorota Bors. A sufficient condition is given which allows to control the systems to the interval, as well as a procedure for finding such a control signal, which leads the systems to a given state, is proposed. Theoretical aspects of general systems concerning a basic behaviour and structure of the systems linkage are studied in the work of Pasqual Esteve-Calvo and Miguel Lloret-Climent. An ordered systems-linkage is stated as well as a role of a turbulence in this context is discussed.
The area of systems modelling is represented in the issue by three papers. The paper by Grzegorz Drałus and Jerzy S´wiatek concerns also complex systems, but it is devoted to their modelling using feed-forward neural networks. This paper confirms that such networks can be used to build global and local dynamic models of dynamic complex systems and gives the illustration of this property using a part of chemical plant of series structure. Marek J. Greniewski presents a very particular problem dealing with a software specification. He shows how to apply known Z-notation for the description of MRP II Software using a general systemic approach to this task. The software implementation of finite-frequency identification method is presented by Ljubov Mikhailova and Albert Alexandrov. A new structure of computer-aided design tool for designers of control systems is proposed. The new variant of finite-frequency identification method with self-tuning of parameters identified is considered.
The following five articles concern uncertain systems, i.e. the topic strongly represented during the congress presentations. Sifeng Liu, Jeffrey Forrest and Robert Vallée give a succinct introduction to the grey systems theory, which contains a short scientific background and a description of a rapid progress that this concept made in a wide spectrum of science. The advances in the grey systems theory and its various successful applications are introduced. The concept of grey modelling is proposed by Yong Wei, Dahong Hu. They propose a new prior check of grey modelling in order to meet a modelling demand of the optimized grey models which have the white exponential law of coincidence. The next two papers employ a formalism of uncertain variables for the description of an uncertainty. The article by Donat Orski concerns the systems composed of operations understood as activities consisting in performing actions with the use of constrained resources. The model of each operation in the form of relation contains an unknown parameter characterized by an expert. The resource allocation algorithm for different cases is presented in the paper. Dariusz Gasior uses the uncertain variables approach for a defined decision-making problem in computer networks. The problem of admission control to avoid the congestion in such networks and to maximize the total utility is considered. The corresponding solution algorithm is described. Fuzzy systems-based approach is used by Grzegorz Bocewicz, Irena Bach and Robert Wójcik for a selected decision-making problem in manufacturing systems. The paper deals with a multi-resource problem in which more than one shared renewable resource type may be required by manufacturing operation and the availability of each type is limited. To solve the problem the constraint programming technique is used.
A very interesting and informative part of the congress presentations was devoted to the history as well as to the educational aspects of cybernetics and systems. The personality of Gordon Pask, a well-known cybernetician as well as his achievements were reminded by Gonçalo Miguel Furtado Cardoso Lopes. In particular, his text concerns exchanges between the fields of cybernetics and arts, and it focuses on Pask’s lifelong exchange with architecture and the manifestation of his ideas in this field. Osvaldo García de la Cerda’s paper shows and explains an innovative educational program in management and engineering that brings students different distinctions in observations to allow facing and managing organizational problems and situations. The program helps to cope with organizational complexity. Gary Boyd and Wojciech M. Jaworski deliver the novel systemic instructional methodology and tools, which can be used to improve students’ learning and development of viable ventures and reliable software systems. The program proposed is based on long-term observations which confirmed its usefulness.
Some papers refer to the application of cybernetic and systemic methodology to different types of systems. Maciej Hojda and Jerzy Józefczyk investigate a two-level decision-making system composed of two interconnected sub-problems: task scheduling and control of the tasks execution. The solution algorithm along with the application to manufacturing systems are presented. The papers by Jernej Belak and Matjaz Mulej as well as Ionela Baltatescu and Petre Prisecaru are focused on economic systems. The first one aims to suggest that awareness of the importance of ethical climate can be of essential meaning for a long-term success of an enterprise. This paper gives some insight into the state of ethical climate in Slovenian enterprises. Michael Heather and Nick Rossiter in their work confirm the possibility of economic planning using computing models. The article provides, among others, some arguments supporting the thesis that computation in a planned economy implies calculus with infinite uncountable domains. The problem of interoperability for information systems is considered in the article by Heather and Rossiter. The application of category theory, restricted to Cartesian-closed categories, to interoperability to increase understanding of the problems and to facilitate the development of practical tools for their solution is proposed.
As the Guest Editor, I wish to acknowledge the contributions of all authors who present very interesting research results. I am indebted to them for their hard work done in due course. Thanks are also due to all anonymous reviewers for their competence and professionalism demonstrated in the review process. They have made a significant contribution to the final version of this special issue.
Jerzy JózefczykGuest Editor