Preface

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In this short note, we outline the history of the Journal, present its recent developments, as well as changes that we are going through, with some attempt at sketching the plans for the future. Some illustrations are provided, concerning the publication statistics, especially with respect to the last 15 years.
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50 years of history, the present and the future

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With this short composition, I’d like to share with you a few events of my scientific life
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Throwback

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This short note is devoted to presentation of the essential points in the history of collaboration between the present-day Department of Computer Science and Artificial Intelligence of the University of Granada and the Systems Research Institute, Polish Academy of Science, with special emphasis on the place, taken in this collaboration by <italic>Control and Cybernetics</italic>. Thus, I mention encounters, conference meetings, jointly undertaken projects, as well as certain selected publications. In doing this, I also try to delineate the substance matter of the collaboration, which formed the backbone of it.
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“Cum grano salis”

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It has turned out that all voting rules fail on some intuitively plausible desiderata. This has led some political scientists to argue that the notion of the will of the people is profoundly ambiguous and the absence of voting equilibria a generic state of a airs. As a constructive remedy to this some authors have introduced the idea of <italic>deliberative democracy</italic>. This view of democracy has much to recommend itself, most importantly the emphasis on individuals in devising the decision alternatives. Some empirical evidence also suggests that the deliberative institutions provide an escape from some of the most notorious incompatibility results in social choice theory. We shall critically examine this suggestion. The view emerging from this examination is that social choice theory and deliberative democracy are complementary, not competing approaches to democratic decision making.
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Social choice, stable outcomes and deliberative democracy

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This paper is devoted to a sufficient second-order condition for a weak local minimum in a simple optimal control problem with one control constraint <italic>G</italic>(<italic>u</italic>) ≤ 0, given by a <italic>C</italic>2-function. A similar second-order condition was obtained earlier by the author for a strong minimum in a much more general problem. In the present paper, we would like to take a narrower perspective than before and thus provide shorter and simpler proofs. In addition, the paper uses the first and second order tangents to the set <italic>U</italic>, defined by the inequality <italic>G</italic>(<italic>u</italic>) ≤ 0. The main difficulty of the proof, clearly shown in the paper, refers to the set, where the gradient <italic>H</italic><italic>u</italic> of the Hamiltonian is small, but the condition of quadratic growth of the Hamiltonian is satisfied. The paper can be valuable for self-explanation and provides a basis for extensions.
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A second-order sufficient condition for a weak local minimum in an optimal control problem with an inequality control constraint

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The Moore-Gibson-Thompson [MGT] dynamics is considered. This third order in time evolution arises within the context of acoustic wave propagation with applications in high frequency ultrasound technology. The optimal boundary feedback control is constructed in order to have on-line regulation. The above requires wellposedness of the associated Algebraic Riccati Equation. The paper by Lasiecka and Triggiani (2022) recently contributed a comprehensive study of the Optimal Control Problem for the MGT-third order dynamics with boundary control, over an infinite time-horizon. A critical missing point in such a study is the issue of uniqueness (within a specific class) of the corresponding highly non-standard Algebraic Riccati Equation. The present note resolves this problem in the positive, thus completing the study of Lasiecka and Triggiani (2022) with the final goal of having on line feedback control, which is also optimal.
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Uniqueness of the Riccati operator of the non-standard ARE of a third order dynamics with boundary control

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We study distributed optimal control problems, governed by space-time fractional parabolic equations (STFPEs) involving time-fractional Caputo derivatives and spatial fractional derivatives of Sturm-Liouville type. We first prove existence and uniqueness of solutions of STFPEs on an open bounded interval and study their regularity. Then we show existence and uniqueness of solutions to a quadratic distributed optimal control problem. We derive an adjoint problem using the right-Caputo derivative in time and provide optimality conditions for the control problem. Moreover, we propose a finite difference scheme to find the approximate solution of the considered optimal control problem. In the proposed scheme, the well-known L1 method has been used to approximate the time-fractional Caputo derivative, while the spatial derivative is approximated using the Grünwald-Letnikov formula. Finally, we demonstrate the accuracy and the performance of the proposed difference scheme via examples.
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Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU)

Distributed optimal control problems driven by space-time fractional parabolic equations

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We consider Helmholtz problems in two and three dimensions. The topological sensitivity of a given cost function <italic>J</italic>(<italic>u</italic>∈) with respect to a small hole <italic>B</italic>∈ around a given point <italic>x</italic>0 ∈ <italic>B</italic>∈ ⊂ Ω depends on various parameters, like the frequency <italic>k</italic> chosen or certain material parameters or even the shape parameters of the hole <italic>B</italic>∈. These parameters are either deliberately chosen in a certain range, as, e.g., the frequencies, or are known only up to some bounds. The problem arises as to whether one can obtain a uniform design using the topological gradient. We show that for 2-d and 3-d Helmholtz problems such a robust design is achievable.
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On the robustness of the topological derivative for Helmholtz problems and applications

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We discuss some aspects of similarity measures in the context of Atanassov’s intuitionistic fuzzy sets (IFSs, for short). IFSs, proposed in 1983, are a relatively new tool for the modeling and simulation and, because of their construction, present us with new challenges as far the similarity measures are concerned. Specifically, we claim that the distances alone are not a proper measure of similarity for the IFSs. We stress the role of a lack of knowledge concerning elements (options, decisions, etc.) and point out the role of the opposing (complementing) elements. We also pay attention to the fact that it is not justified to talk about similarity when one has not enough knowledge about the compared objects/elements. Some novel measures of similarity are presented.
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Similarity measures for Atanassov’s intuitionistic fuzzy sets: some dilemmas and challenges

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We propose a new approach to the bipolar database queries, which involve a necessary (required) and optional (desired) conditions, connected with a non-conventional aggregation operator “and possibly”, combined with a context, exemplified by “find houses which are cheap and – with respect to other houses in town – possibly close to a railroad station”. We use our winnow operator based interpretation of the bipolar queries. We assume that the query, posed by the human user, involves terms, which do not directly relate to attributes, and which are then to be <italic>decoded</italic> using a concept of a query hierarchy, leading to the queries, which involve terms directly related to attribute values. The original query is considered to be of level 0, at the bottom of the precisiation hierarchy, then its required and optional parts are assumed to be bipolar queries themselves, both accounting for context. The precisiation proceeds further, to level 1 queries, level 2, etc. A real estate related example is provided as illustration.
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Faculty of Computer Science, Electronics and Telecommunications

A novel approach to hierarchical contextual bipolar queries: A winnow operator approach

AHEAD OF PRINT

Volume 52 (2023): Issue 2 (June 2023)

Volume 52 (2023): Issue 1 (March 2023)

Volume 51 (2022): Issue 4 (December 2022)

Volume 51 (2022): Issue 3 (September 2022)

Volume 51 (2022): Issue 2 (June 2022)

Volume 51 (2022): Issue 1 (March 2022)

Volume 50 (2021): Issue 4 (December 2021)

Volume 50 (2021): Issue 3 (September 2021)

Volume 50 (2021): Issue 2 (June 2021)

Volume 50 (2021): Issue 1 (March 2021) Special Issue Dedicated to the memory of Gregory E. Kersten Guest Edited by Tomasz Wachowicz, Ewa Roszkowska and Bogumił Kamiński

Control and Cybernetics

 This journal is edited and published by the Systems Research Institute of the Polish Academy of Sciences.  eISSN: 2720-4278 ISSN: 0324-8569   Its main objective is to stimulate the development of broadly conceived systems theory and analysis.  The field of interest covers general concepts, theories, methods, and techniques associated with analysis, modelling, control and management in various systems (e.g., technological, economic, ecological, social).  The journal is particularly interested in results in the following areas of research:  Systems and control theory   General systems theory  Optimal control  Optimization theory  Optimization algorithms  Decomposition and coordination methods  Structural optimization  Data analysis and learning  Artificial intelligence  Machine learning  Modeling and identification  Game theory and polioptimization  Decision and negotiation systems  Stochastic and fuzzy systems  Systems control and management   Systems analysis of national and regional development  Modelling and control of complex systems (in energy, water, industry, agriculture)  Applications of operations research methods  Computer aided management, control and optimal design  Methodological aspects of applications of control and systems methods  The Quarterly journal CONTROL AND CYBERNETICS is being indexed and abstracted in a number of worldwide services (Scopus and Index Copernicus, etc.). Its current issues can be obtained from the Publisher, or via EBSCO and GALE, while issues older than one year are freely available on the web.  Reviews of individual papers from the journal appear in International Abstracts in Operations Research, Mathematical Reviews, and Zentralblatt für Mathematik.  Abstracted in Applied Mechanical Reviews. Indexed also by Polish services BazTech and BazEkon.  See the website control.ibspan.waw.pl.  We hope that Control and Cybernetics will contribute to the development of systems and control sciences and will stimulate and encourage application of systems approach in different areas.  Archiving  Sciendo archives the contents of this journal in Portico - digital long-term preservation service of scholarly books, journals and collections.  Plagiarism Policy  The editorial board is participating in a growing community of Similarity Check System's users in order to ensure that the content published is original and trustworthy. Similarity Check is a medium that allows for comprehensive manuscripts screening, aimed to eliminate plagiarism and provide a high standard and quality peer-review process. 