Formal Representation Research Articles

A Formal Model of IEC 61499-Based Industrial Automation Architecture Supporting Time-Aware Computations

This paper proposes a formal model for industrial cyber-physical systems (CPS) with distributed control based on IEC 61499 standard and supporting time-aware computations for better adaptation to the ever changing environment conditions. Main features of the model include usage of timestamps, flattening, unified and independent behaviour of function block interfaces. This allows to make correct implementation of time-aware systems and significantly simplify the construction of models for verification and simulation, as well as ensure fairness of the model and determinism of the function block system execution at a resource level. The model formalism is based on a well-known abstract state machines (ASM) notion, which can be used as an intermediate formal representation to generate a variety of models for different purposes, e.g. formal verification, and executable code. This paper exemplifies this approach by the generation of models in the SMV language. The paper discusses the time-aware computation concept and its application in a few related case studies.

User interfaces ontology in the cybernetic model of intelligent systems

A model of an intelligent system is proposed for implementing the control and professional use of a knowledge collections related to subject area of software interfaces with external users. The basis of formalization is an abstract model of an intelligent system. It is based on coordinated and balanced invariants of the knowledge representation formalism model. Invariants set includes classes of morphisms for abstract knowledge processing modelling with morphisms' domains, invariants of the multidimensional architecture of intelligent systems components, which includes intercomponent knowledge flows and processes of knowledge synthesis within components, as well as invariants of control agents for abstract knowledge flows and processes within intelligent systems. The intelligent system knowledge base is presented as subject area ontology by non-ordered series of simple knowledge. Fragments of such ontology are distributed between components of intelligent systems three-dimensional architecture. The basis of such structure based on the dimensions of abstraction, structuring and the level of knowledge addressed to and processed within intelligent system's separate components. The ontologies reflect the ideas about the structures of memory and the processes of thinking used to model the schemes of the professional activity of a specialist. The basis for the formalization of such concepts is the fundamental principles of philosophy, linguistics, cognitive psychology, mathematics, and system engineering. This allows deploying a comprehensive system of classes of information structures and processes for complex knowledge synthesizing that support achievement of various cognitive goals implemented by specialists within professional tasks implementation processes. The goals system includes extraction, analysis and application of knowledge about user interfaces. The variety of such goals is modeled by a high-level implementation pattern system. They are composed of basic types of goals and are implemented using knowledge processing cognitive operations. Knowledge structures in the format of semantic hierarchies are used as a unified representation of knowledge. Cognitive goals are realized by combinations of operations on structured knowledge, adapted to special classes of structures.

Dominasi Oligarki dan Ketidakhadiran Partai Politik Hijau di Indonesia

Kerusakan lingkungan dan dampaknya merupakan persoalan yang masih terus berlanjut di Indonesia serta belum cukup mampu untuk mendorong transformasi narasi politik hijau menjadi platform partai politik sebagaimana yang terjadi di negara lain. Literatur sebelumnya seringkali menggunakan kerangka liberalis dan menuntut kesadaran kolektif serta partisipasi masyarakat dalam mengawasi persoalan lingkungan, bukan urgensi keterwakilan politik hijau. Selain itu, perspektif konstitusional dan institusional juga terlampau idealis dan kurang memperhatikan kepentingan individu yang selalu mencari keuntungan. Tulisan ini berupaya untuk menganalisa penyebab dari persoalan lingkungan serta absennya keterwakilan narasi politik hijau dalam bentuk formal dengan menggunakan teori oligarki dan keterwakilan politik. Melalui analisa kualitatif deskriptif dengan metode wawancara dan studi literatur ditemukan: (1) narasi politik Hijau di Indonesia tersebar di berbagai janji kandidat dan partai politik menjelang pemilu, (2) konsentrasi pengelolaan dan penguasaan sumber daya alam merupakan sumber pendapatan oligark yang terus dipertahankan, (3) keterlibatan oligark dalam politik menghambat pertimbangan narasi politik hijau dalam proses pembuatan kebijakan, (4) ketidakhadiran platform partai politik hijau memberi keleluasaan terhadap dominasi oligark, sedangkan (4) konsolidasi platform politik hijau juga terkendala faktor internal berupa pro dan kontra pendirian partai serta faktor eksternal seperti sistem kepartaian dan aturan-aturan pemilihan umum.

Determination of components of route hijack risk by Internet connections topology analysis

The possibility of dynamic routes change between nodes that are not physically connected is a key feature of the Internet routing. The exterior gateway protocol BGP‑4 has been developed to deliver this feature, along with policies and procedures of inter-domain routing. Developed for the network of hundreds nodes that rely on information from each other, after decades BGP-4 is still the same with tens thousands nodes and its crucial lack of routing data integrity. One of the most significant problems deriving from its weaknesses is route leaks and route hijacks. None of the proposed and partially implemented upgrades and add-ons like MANRS and RPKI can not deliver reliable defense against those types of attacks. In this paper, the approach of risk assessment via internetworking links analysis is developed. Although modern information security is based on risk management, in this paper it is proposed to mitigate route hijack risks by enhancing links topology. Estimating the risks of route hijack requires quantitative measurement of the impact of an attack on the routing distortion, and therefore, the loss of information security breach. For this assessment, this paper proposes to use knowledge of the features of the Internet topology at the layer of global routing, which is determined by the interaction of autonomous systems - groups of subnets under common control - according to the routing protocol BGP-4. Based on our formal representation of IP routing, the relationship between topology and the risk of route hijack is shown. A new approach to quantifying information risk using a new risk-oriented model of global routing, which will reflect the properties of Internet nodes in terms of the risk of routes hijack.

On the nondifferentiable exact solutions to Schamel's equation with local fractional derivative on Cantor sets

AbstractThe various aspects of differential calculus are always on the path to progress and excellence, and these trends have been more highlighted in recent decades. More specifically, tremendous advances have been made in the field of fractional calculus. One of the main branches in this field is the local fractional derivative, which has been used successfully to describe many real‐world phenomena in science, and engineering. The present contribution aims to adopt a newly proposed analytical technique to construct exact solutions to local fractional Schamel's equation defined on Cantor sets. To this end, a set of elementary functions are constructed on Cantor sets is defined. Furthermore, the combination of these modified functions is utilized to constitute a formal representation of the searched exact solution for the equation. Numerical simulations related to some of the obtained solutions are also included. The acquired results confirm that the method used is not only very straightforward but also efficient in terms of application. In order to perform complicated and tedious calculations while solving this problem, the use of a symbolic computational packages in Maple or Mathematica is inevitable. The work emphasizes the power of the employed method in providing various exact solutions to different physical problems involving local fractional derivatives.

Complexity of Nonempty Existence Problems in Incomplete Argumentation Frameworks

Abstract argumentation frameworks (AFs) are a prevailing model for the formal representation of argumentations in AI research. The generalized model of incomplete AFs extends the basic model by allowing for the representation of unquantified uncertainty about the existence of elements in an argumentation. For this extended model of AFs, we formally define a natural generalization of the nonempty existence problem, which asks whether there exists a nonempty set of arguments satisfying the conditions specified by a given semantics. Focusing on the fundamental semantics for incomplete AFs and considering a possible and a necessary variant of the nonempty existence problem, this yields a family of related problems, and we provide a full analysis of their computational complexity.

Ontologies' Closures Modeling by Formalisms of Semantic Hierarchies

Schemes are studied for modeling the complex knowledge structures as synthesized from knowledge areas ontologies elements. These structures applications relate to knowledge life cycles and knowledge flows stages within intelligent systems. The format of semantic hierarchies is proposed as unified and universal for the synthesis of these structures. This allows replacing the general case of knowledge algebraic structures by special case of semantic hierarchies. Constructing the synthesized knowledge structures is performed by special operations knowledge alge­braic structures in any knowledge representation formalisms. These operations simulate fundamental mathematical systems functional aspects. They are adapted to the knowledge formalisms attributes. Attributes are explored within different knowledge areas. They associated generally with thinking operations and mind memory structure. Datasets (operations bases) of synthesis processes operations are constructed as special classes of knowledge with a uniform structure. Ontologies for considered knowledge areas are used as source of such bases constructing. Ontologies closures are defined as sets of knowledge that may be constructed off ontologies elements by synthesis operations. They determine the ontologies expressive capabilities. The constructs and operations over ontologies, that proposed at descriptive logics, can be modelled by knowledge complete structural representations, adopted for semantic hierarchies formalisms. Such formalisms are convenient for simulating knowledge presentation and processing. They form foundation for constructing intelligent systems abstract and applied models.. The possibility is proved for trans­ferring the knowledge properties and knowledge processing schemes at semantic hierarchies to the general case of knowledge algebraic structures. The schemes for modeling the ontological constructions as semantic hierarchies are given. This proves possibility of applying such formalisms as the basis for modeling synthesis processes in ontolo­gies. Such schemes allow constructing the ontologies closures as generated by knowledge-processing operations sequences. Last fact means possibility for formalisms of semantic hierarchies to be uniform foundation of modelling the knowledge flows and knowledge transforming processes by intelligent systems.

Development of the Theory of Macrosystems as a Necessary Condition for Improving Quality of Transport Modelling

The issues of development of the theory of transport macrosystems are considered regarding results obtained in the works of A. G. Wilson, Yu. S. Popkov, A. V. Gasnikov, E. V. Gasnikova and others. The transport macrosystem is considered a complex multicomponent system to which series of thermodynamic analogy can be applied (equilibrium state, information entropy as a function of state parameters, the presence of basic phenomenological schemes for filling of states with elements, etc.). To further develop the theory of development of transport modelling, which is the objective of the article, it is proposed to consider circumstances that reflect modern trends in development of transport systems: diversity of transport systems, dynamic nature of its functioning, many different elements that can obey different models for filling of states. To implement this task, various methods are used: equation of the transport process introduced by the author, which makes it quite easy to go to quasi-dynamic formulations of transport modelling problems, as well as a general formal representation of the system as a set of elements, which is determined based on the analysis of many works of domestic authors. The conclusion is dedicated to discussion of issues of further development of the theory of transport macrosystems in a dynamic setting.

ТРАДИЦИОННАЯ КУЛЬТУРА КОРЕННЫХ НАРОДОВ СЕВЕРА КАК ОБЪЕКТ ДИЗАЙН-ИНТЕРПРЕТАЦИИ (НА ПРИМЕРЕ ОБСКИХ УГРОВ)

The article presents the study of the design application, namely practical use of the elements of the traditional culture of Ob Ugric people, that include scenic compositions of rites and rituals as well as contextual attributes and decorations (ornaments). The research goal is to formulate a method of design interpretation that provides for ethically and efficiently embedment of elements of traditional culture into the semantic and image-bearing field of contemporary multicultural reality. This method is expected to further address the challenge of the deliberate development of a new/hybrid culture in the studied region (and, in a broad sense, in the entire territory of the Russian North). The novelty of the research is the detailed exploration of structural elements of the chosen culture in combination with the synchronous selection of tools, such as concepts of social and human sciences, as well as the means of a design that include formal, spatial, social, economic, ecological and technological representations.
 The basic methodology for analyzing research materials a systemic approach and structural elements of culture such as ornaments, rituals, and rituals were examined in a united figurative and semantic context. The combination of the methods of historical analysis and field ethnography allowed to identify the content and evolution of the studied phenomenon, as well as to consider individual cultural patterns and actions in real place and time.
 The proposed method of interpretation includes two following logical steps of identification: (1) the non-changeable content of the cultural core, which provides an inherent connection with the environment where the given culture takes place, and (2) the outer layer (material shell) that is available for transformation/modernization. As a result, the proposed method is presented through, first, the theoretical principles of a proper design interpretation based on the existing examples of cultural borrowings (with the case of traditional ornaments); and second, an educational experiment of designing a new Northern culture through borrowing and interpreting the traditional festivity “The Crow’s Day,” with a potential implementation within the local tourism industry. 
 The final part describes the broad research relevance of the findings, along with the limitations and directions for further research.

The Probabilistic Description Logic

AbstractDescription logics (DLs) are well-known knowledge representation formalisms focused on the representation of terminological knowledge. Due to their first-order semantics, these languages (in their classical form) are not suitable for representing and handling uncertainty. A probabilistic extension of a light-weight DL was recently proposed for dealing with certain knowledge occurring in uncertain contexts. In this paper, we continue that line of research by introducing the Bayesian extension of the propositionally closed DL . We present a tableau-based procedure for deciding consistency and adapt it to solve other probabilistic, contextual, and general inferences in this logic. We also show that all these problems remain ExpTime-complete, the same as reasoning in the underlying classical .

Rough set reasoning using answer set programs

Reasoning about uncertainty is one of the main cornerstones of Knowledge Representation. Formal representations of uncertainty are numerous and highly varied due to different types of uncertainty intended to be modeled such as vagueness, imprecision and incompleteness. There is a rich body of theoretical results that has been generated for many of these approaches. It is often the case though, that pragmatic tools for reasoning with uncertainty lag behind this rich body of theoretical results. Rough set theory is one such approach for modeling incompleteness and imprecision based on indiscernibility and its generalizations. In this paper, we provide a pragmatic tool for constructively reasoning with generalized rough set approximations that is based on the use of Answer Set Programming (Asp). We provide an interpretation of answer sets as (generalized) approximations of crisp sets (when possible) and show how to use Asp solvers as a tool for reasoning about (generalized) rough set approximations situated in realistic knowledge bases. The paper includes generic Asp templates for doing this and also provides a case study showing how these techniques can be used to generate reducts for incomplete information systems. Complete, ready to run clingoAsp code is provided in the Appendix, for all programs considered. These can be executed for validation purposes in the clingoAsp solver.

Carl Menger's Grundsätze as a Foundation for Contemporary Entrepreneurship Research

This paper takes the subjective value theory, conception of economic goods, and the hierarchy of needs from Carl Menger's Grundsätze der Volkswirtschaftslehre (1871) to elaborate a model of strategic entrepreneurship. Menger's account of subjective valuation by buyers of goods in market exchange fills a gap in most conceptual approaches to entrepreneurship, which are based on a highly impermeable boundary around the entrepreneurial firm. We examine how this account "closes" an economic model of entry for an entrepreneurial firm in an existing rivalry network by making the assessment of value explicit with respect to buyer needs relative to goods sold by incumbent firms. A formal representation of Menger's needs hierarchy in the face of qualitatively different market goods is the centerpiece of the strategic entrepreneurship model. This conceptual model is tied to methods of eliciting subjective valuations of product attributes and buyer needs fulfilment from the literatures of consumer behavior, marketing, and organizational psychology. This serves as a methodological basis for scholarship in entrepreneurship.

Assessing High Performers in the Life Sciences: Characteristics of Exams Used at the International Biology Olympiad (IBO) and Their Implications for Life Science Education.

For decades, studies have revealed students’ decreasing interest in science. Extracurricular learning opportunities—the Science Olympiads being a publicly well-known example—are an important means identified to tackle this challenge and help students further differentiate their interests. Better understanding the underlying constructs and characteristics of Science Olympiad exams can provide several implications not just for Science Olympiads, but also science education more broadly, for example, with regard to how the competitions’ international juries defines expectations for high performance in the life sciences. This study analyzes exams set by the International Biology Olympiad (IBO) as an example for a top-tier international competition in the life sciences. The findings extend previous works on test item characteristics toward student competitions and high-performer education. We conducted a systematic analysis of N = 703 closed-ended and laboratory test items from six IBO assessment years across the competition’s history. A categorical framework was developed to analyze items according to four areas: formal characteristics, content and practices, cognitive aspects, and the use of representations. Our findings highlight assessment characteristics used to challenge high-performing students. We derive implications for general life sciences education, as well as for further developing the assessments of Science Olympiads.

Formal reasoning of knowledge in systems engineering through epistemic modal logic

AbstractLarge‐scale systems engineering projects consist of hundreds to thousands of agents (stakeholders, managers, designers, etc.) spread across the organizational hierarchy. Each of these agents possesses knowledge in some form or the other, be it the knowledge of stakeholder needs, domain‐specific knowledge, knowledge of rules and regulations, knowledge gained from experience on previous projects, etc. It is important to formally represent this knowledge possessed by various agents in the systems engineering lifecycle, as this will enable knowledge reuse, reasoning capabilities, inferring new knowledge, and mitigate misinterpretation of knowledge as prevalent in document‐centric approaches. Such a formal representation will also help alleviate some of the challenges posed by the current document‐centric approaches concerning project delays and cost overruns in the development of large‐scale systems. This paper focuses on formally representing knowledge that exists in various phases of the systems engineering lifecycle by leveraging epistemic modal logic. Descriptive examples are used to demonstrate the practical reasoning capabilities of such a formal representation of knowledge in systems engineering projects.

Investigating the Flexibility of the MBSE Approach to the Biomass Mission

Model-based systems engineering (MBSE) represents a move away from the traditional approach of document-based systems engineering (DBSE), and is used to promote consistency, communication, clarity, and maintainability within systems engineering projects. MBSE offers approaches that can address issues associated with cost, complexity, and safety. One way that this can be achieved is by performing early functional validation of the high-level spacecraft functional avionics system. The use case discussed in this article focusses on the Biomass model, a systems modeling language-based representation of the Biomass Earth-observation mission. The MBSE approach is used to calculate the required size of the data handling unit onboard the Biomass spacecraft. The functional response of the system in terms of the onboard memory usage throughout the mission is simulated. Traditionally, this level of analysis would not be available at this early stage. The approach aims to replace ad hoc, spreadsheet-based calculations with a formal representation of the system that can be executed, interrogated and quantified. The flexibility of this MBSE approach is demonstrated by applying changes to the Biomass project and assessing the time required to implement these changes in the Biomass model and propagate them through to the results of the simulation. The changes have been made independently of each other and include: changes to the logical architecture, changes to the functional definition, changes to the mission profile, and changes to the requirements. Potential areas for improvement regarding the structure of the Biomass model are highlighted and discussed.

A uniform model of computational conceptual blending

We present a mathematical model for the cognitive operation of conceptual blending that aims at being uniform across different representation formalisms, while capturing the relevant structure of this operation. The model takes its inspiration from amalgams as applied in case-based reasoning, but lifts them into category theory so as to follow Joseph Goguen’s intuition for a mathematically precise characterisation of conceptual blending at a representation-independent level of abstraction. We prove that our amalgam-based category-theoretical model of conceptual blending is essentially equivalent to the pushout model in the ordered category of partial maps as put forward by Goguen. But unlike Goguen’s approach, our model is more suitable to capture computational realisations of conceptual blending, and we exemplify this by concretising our model to computational conceptual blends for various representation formalisms and application domains.

CAMO: A context-aware movie ontology generated from LOD and movie databases

An ontology is a formal representation of domain knowledge as a set of concepts and their relationships in structured format. Besides various applications, ontology has been frequently used for the development of movie recommender systems that aim to predict the rating a user would give to a movie. Though recommender system is a well-studied research field, issues like cold-start, data sparsity, limited-content, and long tail are still open challenges. Context-aware recommender systems have been considered by many researchers to deal with some of these issues. However, non-existence of domain ontology containing contextual information is the major hindrance for the development of such systems. This is mainly due to the fact that datasets used in most of the existing context-aware recommender systems are either synthetic or generated through surveys. In this paper, we present the development of a context-aware movie ontology (CAMO) that contains movie concepts, relationships, and various representational and interactional contextual features. Since existing movie databases do not contain all contextual features, we have generated a real-world movie dataset from Linked Open Data (LOD) and movie databases like IMDB and Rotten Tomatoes that contain complete context-based movie profiles. CAMO contains the conceptualization of total 1103 movies. Since users generally express their opinion over the interactional features like story, direction, music, visual effects, etc. of the movies, CAMO also contains aspect-based sentiment polarity identified from the reviews generated by 78056 users and 235 critics. The usefulness of CAMO is empirically evaluated using two similarity measures and two state-of-the-art recommendation methods, and it seems a useful movie knowledgebase for the development of context-aware movie recommendation systems. The source code of CAMO is uploaded at https://github.com/vineet-sejwal/CAMO for research and academic reference purposes. The generated movie dataset containing movie details, user ratings, and reviews generated by both users and critics is also uploaded, and it can be used as a benchmark dataset to evaluate movie recommender systems.

Automated Security Risk Identification Using AutomationML-Based Engineering Data

Systems integrators and vendors of industrial components need to establish a security-by-design approach, which includes the assessment and subsequent treatment of security risks. However, conducting security risk assessments along the engineering process is a costly and labor-intensive endeavor due to the complexity of the system(s) under consideration and the lack of automated methods. This, in turn, hampers the ability of security analysts to assess risks pertaining to cyber-physical systems (CPSs) in an efficient manner. In this work, we propose a method that automatically identifies security risks based on the CPS's data representation, which exists within engineering artifacts. To lay the foundation for our method, we present security-focused semantics for the engineering data exchange format AutomationML (AML). These semantics enable the reuse of security-relevant know-how in AML artifacts by means of a formal knowledge representation, modeled with a security-enriched ontology. Our method is capable of automating the identification of security risk sources and potential consequences in order to construct cyber-physical attack graphs that capture the paths adversaries may take. We demonstrate the benefits of the proposed method through a case study and an open-source prototypical implementation. Finally, we prove that our solution is scalable by conducting a rigorous performance evaluation.

Defining Theoretical Foundations to Unified Metamodel For Model Reusability

Background: In model-driven development, model transformation transforms one model to another between different phases of software engineering. In model transformation, metamodel plays a vital role which defines the abstract syntax of models and the interrelationship between their elements. A unified metamodel defines an abstract syntax for both source and target models when they share core elements. Theoretical approaches define language and platform independent representation of models in software engineering. This paper investigates the theoretical foundation to this unified meta-modelling for their consistent transformation. Objective: This paper aims to define the formal foundations to the unified metamodel for generating implementation from design specifications and model reusability. Method: In this paper, the study considers transformation from design to implementation and vice versa using theoretical foundations to build a verified software system. Results: The related tools provide a formal representation of the design phase for verification purpose. Our approach provides a set-theoretical foundation to the unified metamodel for model transformation from USE (UML/OCL) to Spec#. In other words, our approach defines the formal foundation to define a model which consists of all the required properties for verification at the design and implementation phase. Conclusion: This paper introduced a new set of the theoretical framework which acts as an interface between the design and implementation to generate verified software systems.

Simflowny 3: An upgraded platform for scientific modeling and simulation

Simflowny is an open platform which automatically generates efficient parallel code of scientific dynamical models for different simulation frameworks. Here we present major upgrades on this software to support simultaneously a quite generic family of partial differential equations. These equations can be discretized using: (i) standard finite-difference for systems with derivatives up to any order, (ii) High-Resolution-Shock-Capturing methods to deal with shocks and discontinuities of balance law equations, and (iii) particle-based methods. We have improved the adaptive-mesh-refinement algorithms to preserve the convergence order of the numerical methods, which is a requirement for improving scalability. Finally, we have also extended our graphical user interface (GUI) to accommodate these and future families of equations. This paper summarizes the formal representation and implementation of these new families, providing several validation results. Program summaryProgram Title: SimflownyCPC Library link to program files:https://doi.org/10.17632/g9mcw8s64f.2Licensing provisions: Apache License, 2.0Programming language: Java, C++ and JavaScriptJournal Reference of previous version: Comput. Phys. Comm. 184 (2013) 2321–2331, Comput. Phys. Comm. 229 (2018), 170–181Does the new version supersede the previous version?: YesReasons for the new version: Additional featuresSummary of revisions: Expanded support for Partial Differential Equations, meshless particles and advanced Adaptive Mesh Refinement.Nature of problem: Simflowny generates numerical simulation code for a wide range of models.Solution method: Any discretization scheme based on either Finite Volume Methods, Finite Difference Methods, or meshless methods for Partial Differential Equations.Additional comments: Simflowny runs in any computer with Docker [1]. Installation details can be checked in the documentation of Simflowny [2]. It can also be compiled from scratch on any Linux system, provided dependences are properly installed as indicated in the documentation. The generated code runs on any Linux platform ranging from personal workstations to clusters and parallel supercomputers. The software architecture is easily extensible for future additional model families and simulation frameworks. Full documentation is available in the wiki home of the Simflowny project [2].