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The Internet of Things (IoT) is a network of devices that can communicate and cooperate over the Internet. As the IoT expands, guaranteeing the dependability and accuracy of communication systems becomes increasingly important. One of the key challenges faced in the process of system development is the need to detection the errors in the early phases of system development. Formal techniques are the gold standard for ensuring a system's correctness. In the context of the IoT, this paper presents an Event-B formal model for the verification of the correctness of Content-Based Publish/Subscribe Systems (CBPS). We developed our model using Event-B, which is an incrementally formal technique with a plugin-supported platform. Furthermore, it supports both theorem proving and model checking. The incremental method uses a series of refining processes to help manage complexity. The paper offers a thorough exposition of the CBPS architecture, with an emphasis on decentralised design, reliable message delivery, and message ordering. This formalised method ensures that the CBPS system satisfies its criteria and free of errors. As a case study for our concept, we employ a smart home system. Finally, we validate and verify the formal model using proof obligations and the Rodin platform. [ABSTRACT FROM AUTHOR]

A purposely naïve and semi-empirical model allows for the reproduction of the phenomenological behavior of any real microbial culture by adjusting the values of three parameters, which have a biological meaning only for a virtual microbial culture that mimics the behavior of the real ones. Any genomic, biochemical, and physical peculiarity (microbial species, physiological condition, pH, water activity, temperature, etc.) that distinguishes one real culture from another is "translated" to an effect of the degree of progress of the population density and cell age in the virtual culture. The model leads to a self-consistent description of the growth curve, which looks like the result of an autocorrelation effect. This explains why, in spite of genomic and physiologic differences, all the growth curves show a sigmoid trend. The traditional growth curve and the subsequent exponential decay in the log(N)-vs-t plot can be replaced by straight-line trends when referring to the degree of progress of the population density of the virtual culture. [ABSTRACT FROM AUTHOR]

This paper develops a model of voter turnout that embeds Riker and Ordeshooks (1968 Am. Pol. Sci. Rev. 62, 25-42 (doi:10.2307/1953324)) calculus of voting into the context of a social network. In the model, an individuals expressive benefits to voting depend on the behaviour of their social contacts. We show that there may be multiple equilibria and analyse how these equilibria depend on the structure of the network. We discuss six empirical implications of the model for turnout, some of which suggest novel answers to longstanding puzzles in the turnout literature, such as: why are higher income individuals more likely to vote even in cases when registration costs are low? Why is turnout so difficult to predict? Why does lowering registration costs disproportionately increase turnout among high-income voters? And why do we observe inertia in turnout across elections?

A purposely naïve and semi-empirical model allows for the reproduction of the phenomenological behavior of any real microbial culture by adjusting the values of three parameters, which have a biological meaning only for a virtual microbial culture that mimics the behavior of the real ones. Any genomic, biochemical, and physical peculiarity (microbial species, physiological condition, pH, water activity, temperature, etc.) that distinguishes one real culture from another is “translated” to an effect of the degree of progress of the population density and cell age in the virtual culture. The model leads to a self-consistent description of the growth curve, which looks like the result of an autocorrelation effect. This explains why, in spite of genomic and physiologic differences, all the growth curves show a sigmoid trend. The traditional growth curve and the subsequent exponential decay in the log(N)-vs-t plot can be replaced by straight-line trends when referring to the degree of progress of the population density of the virtual culture.

In the process of both European and American state development, legal institutions developed from many separate venues with overlapping jurisdictions to a hierarchical structure with authority concentrated in the lawmaking institutions of the state. This paper investigates the effects of concentrating authority in an institution whose decisions in a current conflict also bind other (subordinate) institutions deciding future conflicts. To do so, I present a simple formalization of this dimension of legal authority and use a formal model to analyze the effects of varying this dimension on competition among groups in society. The structure of legal authority is formalized as a probability that outcomes of group conflict in the current round determine outcomes in future rounds. In the model, concentrating legal authority increases incentives for competing groups to invest in political organization. In turn, this increases political inequality: As all groups invest more effort, groups with a resource advantage are better able to make use of their advantage. This paper contributes to our understanding of state development as well as ways in which the legal authority of the state structures contemporary politics. [ABSTRACT FROM AUTHOR]

Verification of real-time system properties using formal models can improve system design and quality. The Timed Petri net is a formal model for modelling and designing real-time systems with time constraints. Furthermore, model checking is a formal verification method used to verify system properties using model checkers. This article proposes an automated transformation system for mapping a Timed Petri net into one of the common model checkers, the SPIN PROMELA model, to verify real-time system properties. This approach enables the combination of two modelling paradigms and supports system verification using system design models. In this study, the system properties were verified using both the simulation method and linear temporal logic formulas supported by the SPIN model checker. Timed Petri net models of two different case studies, a central server computer system and a manufacturing Kanban system were considered to verify the boundedness, liveness and system behavioral properties using the proposed transformation system.

The digital transformation of critical infrastructures, such as energy or water distribution systems, is essential for their smart management. Faster issue identification and smoother services enable better adaptation to consumers' evolving demands. However, these large-scale infrastructures are often outdated. Their digital transformation is crucial to enable them to support societies. This process must be carefully planned, providing guidance that ensures that the data they rely on are dependable and that the system remains fully operational during the transition. This paper presents a formal model that supports reliable data acquisition in legacy critical infrastructures, facilitating their evolution towards a data-driven smart system. Our model provides the foundation for a flexible transformation process while generating dependable data for system management. We demonstrate the model's applicability in a use case within the water distribution domain and discuss its benefits. [ABSTRACT FROM AUTHOR]

The computational model of school achievement represents a novel approach to theorizing school achievement, conceptualizing educational interventions as modifications to students’ learning curves. By modeling the process and products of educational achievement simultaneously, this tool addresses several unresolved questions in educational psychology through computational modeling. For example, prior research has highlighted perplexing inconsistencies in the relationship between time spent on task and academic achievement. The present simulation reveals that even under the assumption that time-on-task always positively contributes to achievement, the correlations between time-on-task and achievement can vary substantially across different contexts and, in some cases, may even be negative. Analysis of the correlation between prior knowledge and knowledge gains uncovers similar patterns. The computational model of school achievement presents a framework, bolstered through simulation, enabling researchers to formalize their assumptions, address ongoing debates, and design tailored interventions that consider both the school environment and individual student contexts. [ABSTRACT FROM AUTHOR]

In the article, a modification of formal model of risk analysis (FoMRA) was proposed. The modified FoMRA1 method takes into account the guidelines of ISO/IEC 27001 and ISO/IEC 27005 standards. The applied modification and abstraction by resources and security controls (also called countermeasures) significantly shortened the time of risk weight calculation in comparison with the MEHARI method. An attempt was also made to further reduce the time of risk analysis using agents collecting information and data from various network nodes, from operating systems and devices, and additional agents containing information on reports on security procedures, security services, security management and organizational activities related to the information systems (maintenance, insurance, outsourcing contracts, etc.) and transfer it to the local FoMRA1 database. The obtained results indicate that the proposed method together with agents installed in various nodes enable a quick reaction to the system threats and prevention of their impacts (quasi-real-time security monitoring system). [ABSTRACT FROM AUTHOR]

The use of agents across diverse domains within computer science and artificial intelligence is experiencing a notable surge in response to the imperatives of adaptability, efficiency, and scalability. The subject of this study is the application of formal methods to furnish a framework for knowledge interpretation with a specific focus on the agent-based paradigm in software engineering. This study aims to advance a formal approach to knowledge interpretation by leveraging the agent-based paradigm. The objectives are as follows: 1) to examine the current state of the agent-based paradigm in software engineering; 2) to describe the basic concepts of the knowledge interpretation approach; 3) to study the general structure of the rule extraction task; 4) to develop the reference structure of knowledge interpretation; 5) to develop a multi-agent system architecture; 6) and to discuss the research results. This study employs formal methods, including the use of closed path rules and predicate logic. Specifically, the integration of closed path rules contributes to the extraction and explication of facts from extensive knowledge bases. The obtained results encompass the following: 1) a rule mining approach grounded in closed path rules and tailored for processing extensive datasets; 2) a formalization of relevance that facilitates the scrutiny and automated exclusion of irrelevant fragments from the explanatory framework; and 3) the realization of a multi-agent system predicated on the synergy among five distinct types of agents, dedicated to rule extraction and the interpretation of acquired knowledge. This paper provides an example of the application of the proposed formal tenets, demonstrating their practical context. The conclusion underscores that the agent-based paradigm, with its emphasis on decentralized and autonomous entities, presents an innovative framework for handling the intricacies of knowledge processing. It extends to the retrieval of facts and rules. By distributing functions across multiple agents, the framework offers a dynamic and scalable solution to effectively interpret vast knowledge repositories. This approach is particularly valuable in scenarios where traditional methods may struggle to cope with the volume and complexity of information.

Verification of real-time system properties using formal models can improve system design and quality. The Timed Petri net is a formal model for modelling and designing real-time systems with time constraints. Furthermore, model checking is a formal verification method used to verify system properties using model checkers. This article proposes an automated transformation system for mapping a Timed Petri net into one of the common model checkers, the SPIN PROMELA model, to verify real-time system properties. This approach enables the combination of two modelling paradigms and supports system verification using system design models. In this study, the system properties were verified using both the simulation method and linear temporal logic formulas supported by the SPIN model checker. Timed Petri net models of two different case studies, a central server computer system and a manufacturing Kanban system were considered to verify the boundedness, liveness and system behavioral properties using the proposed transformation system. [ABSTRACT FROM AUTHOR]

In this article, I investigate a puzzling feature of American urban politics: cities with more liberal residents tend to enact more restrictive zoning policies and permit fewer new housing units each year than similar conservative cities. To help explain this puzzle, I develop a formal model in which local governments regulate the size of their population to balance the benefits of agglomeration with the costs of congestion. To defend against congestion externalities imposed by new residents, cities enact zoning policies that undersupply housing relative to the social optimum. In liberal cities, where residents value the benefits of agglomeration the most, this undersupply of housing is the most severe. [ABSTRACT FROM AUTHOR]

The use of agents across diverse domains within computer science and artificial intelligence is experiencing a notable surge in response to the imperatives of adaptability, efficiency, and scalability. The subject of this study is the application of formal methods to furnish a framework for knowledge interpretation with a specific focus on the agent-based paradigm in software engineering. This study aims to advance a formal approach to knowledge interpretation by leveraging the agent-based paradigm. The objectives are as follows: 1) to examine the current state of the agent-based paradigm in software engineering; 2) to describe the basic concepts of the knowledge interpretation approach; 3) to study the general structure of the rule extraction task; 4) to develop the reference structure of knowledge interpretation; 5) to develop a multi-agent system architecture; 6) and to discuss the research results. This study employs formal methods, including the use of closed path rules and predicate logic. Specifically, the integration of closed path rules contributes to the extraction and explication of facts from extensive knowledge bases. The obtained results encompass the following: 1) a rule mining approach grounded in closed path rules and tailored for processing extensive datasets; 2) a formalization of relevance that facilitates the scrutiny and automated exclusion of irrelevant fragments from the explanatory framework; and 3) the realization of a multi-agent system predicated on the synergy among five distinct types of agents, dedicated to rule extraction and the interpretation of acquired knowledge. This paper provides an example of the application of the proposed formal tenets, demonstrating their practical context. The conclusion underscores that the agent-based paradigm, with its emphasis on decentralized and autonomous entities, presents an innovative framework for handling the intricacies of knowledge processing. It extends to the retrieval of facts and rules. By distributing functions across multiple agents, the framework offers a dynamic and scalable solution to effectively interpret vast knowledge repositories. This approach is particularly valuable in scenarios where traditional methods may struggle to cope with the volume and complexity of information. [ABSTRACT FROM AUTHOR]

The created methodology offers a technique of projecting a mental model obtained based on visual analytics into the space of machine use. The efficiency of the use of visual analytics consists of mapping the multidimensional space of features into the visual space and providing a mechanism for formalizing the mental model. This allows a person to be integrated into the process of formation and training of a machine learning model. Examples that demonstrate the efficiency of using the proposed methodology for solving practical problems are given. [ABSTRACT FROM AUTHOR]

We propose a technique for projecting a mental model based on visual analytics onto the space of machine use. The efficiency of visual analytics consists in mapping the multidimensional space of features onto the visual space and providing a mechanism for formalizing the mental model. This allows a person to be integrated into the process of formation and training a machine learning model. Examples that demonstrate the efficiency of the proposed methodology for solving practical problems are given. [ABSTRACT FROM AUTHOR]

A system based on the internet of things (IoT) consists of services deployed across several devices that collaborate to fulfil IoT system goals. The growth in the number of IoT services that has occurred concurrently with the growth in the number of IoT devices is posing a significant difficulty for the process of service composition. In order to satisfy increasing demand and rapid expansion while keeping a certain level of quality of service, IoT systems need a scalable IoT service composition. However, building the correct scalable service composition is not guaranteed in IoT systems. This paper proposes formal modeling and verification of the scalability in IoT service composition at design time based on Event-B formal method. To fulfil the requirements of IoT service composition, the proposed model addresses more key qualities, mainly availability and interoperability. Further, by relying on the refinement technique, we create our model sequentially from the requirements analysis level to the target level. Finally, we validate and verify the correctness of the proposed formal model using of the Rodin platform and several proof obligations. Our verified model of the scalable IoT service composition has met its 44 proof obligations, and the Rodin prover was responsible for automatically addressing all of these proof obligations. [ABSTRACT FROM AUTHOR]

Research Summary: This paper uses formal modeling and simulation to develop a more robust theory of how entrepreneurs gain access to human capital resources through their strong and weak social network ties. Whereas prior work focuses on the informational context in which an endeavor operates (i.e., is it risky or uncertain), the models developed in this paper introduce untested assumptions implicit in prior work regarding strong tie superiority, the effects of social media, and human capital heterogeneity. Through a series of simulation analyses, the paper explores a broad range of values for these alternative assumptions and identifies the conditions under which strong and weak ties are the most likely source of human capital for entrepreneurial endeavors. Managerial Summary: Entrepreneurs often need to enlist the support of others to achieve their objectives. This paper develops a better understanding of how entrepreneurs can access the human capital their endeavors require through their social network ties. The paper explores a broad range of conditions to identify when an entrepreneur's strong social network ties are the most likely source of human capital—and when the entrepreneur's weak ties are the most likely source. This paper challenges the assumption that strong ties have an inherent advantage over weak ties in entrepreneurial settings, investigates the impact of social media networks, and highlights the challenges entrepreneurs face when attempting to enlist the support of individuals with different types of human capital. [ABSTRACT FROM AUTHOR]

Model‐Driven Development (MDD) is one of the important approaches to develop complex software systems. This approach tries to model a system in high‐abstraction level. Then through applying multiple transformations step by step, the model abstraction level is reduced and finally yields to executable code. As a result, Model transformation (MT) plays a pivotal role on the realization of MDD goals. Due to the increasing complexity of software systems, MTs naturally become more complex. Hence, qualitative technical issues may be overlooked or forgotten in these model transformations. To alleviate these issues in terms of technical debts/code smells in MTs, we can apply MT patterns. A main drawback on applying patterns is that most of them are cataloged in informal language. Additionally, construction of a conceptual framework to help MT designers through applying patterns requires a precise specification of the underlying MT patterns. With a formal basis, this paper is trying to realize the proposed framework. Hence, some of the existing well‐known MT patterns are formalized. Then based on the identified common technical debts/code smells in MTs, a designer can be directed to apply the appropriate patterns and resolve the detected problems iteratively. For the applicability and functionality of the proposed framework, several examples of problematic model transformations in terms of quality flaws were considered and resolved using the appropriate patterns. We consider the Epsilon Transformation Language (ETL) cases of model transformations in this paper, and other similar MT languages could be treated using the same measures and patterns as well. [ABSTRACT FROM AUTHOR]

This paper develops a model of voter turnout that embeds Riker and Ordeshook’s (1968 Am. Pol. Sci. Rev. 62, 25–42 (doi:10.2307/1953324)) calculus of voting into the context of a social network. In the model, an individual’s expressive benefits to voting depend on the behaviour of their social contacts. We show that there may be multiple equilibria and analyse how these equilibria depend on the structure of the network. We discuss six empirical implications of the model for turnout, some of which suggest novel answers to longstanding puzzles in the turnout literature, such as: why are higher income individuals more likely to vote even in cases when registration costs are low? Why is turnout so difficult to predict? Why does lowering registration costs disproportionately increase turnout among high-income voters? And why do we observe inertia in turnout across elections?

Moving Block is a railway signaling concept that paves the way for increasing line capacity while reducing maintenance and operating costs. Its implementation relies on autonomous solutions for train localization, mainly based on GNSS technology. However, the introduction of such technological innovations leads to the emergence of new risks. These risks need to be investigated meticulously, and some confidence level needs to be assigned to GNSS-based localization solutions in railways while considering various settings. The contribution of this paper falls within this context by bringing formal approaches into play in order to evaluate performance and safety properties related to the use of GNSS-based virtual balises for train localization. Specifically, the adopted model-based approach consists in translating the relevant behavior of the localization system through configurable timed and probabilistic automata. The elaborated models being parameterizable, various test scenarios, considering a wide range of configurations, can be investigated. Quantitative and qualitative analysis results can be generated on the basis of our models by means of statistical model-checking algorithms implemented in the UPPAAL-SMC modeling and verification tool. A case study is used to illustrate the application of the presented approach, and various numerical analysis results are provided. As the present contribution implements a model-driven approach to perform safety analysis in railways, it is fully in line with the increasing willingness to reduce recourse to on-site tests in the sector. Such tests are indeed costly and time-consuming, thus jeopardizing the introduction of technical innovations in railways.

In this article we introduce a formal approach to the evolution of documents with particular attention to the philological perspective and the typical related issues. We propose a mathematical model capable of formalizing various complex phenomena in various research fields such as Computational Linguistics, Digital Philology and Software Engineering, in particular when this is applied to the analysis of documents and texts of historical and literary interest.

The concept of modernizing outdated systems in critical infrastructure through digital transformation has been a widely discussed topic nowadays. Following the transition of energy systems, the attention has now shifted towards digitalizing the water distribution systems. These systems are large-scale but outdated systems that frequently encounter various issues and upgrading them would enable easier to identify issues and provide smoother, more efficient service. However, this process requires cautious planning and guidance to ensure that the generated data is reliable, and the system remains operational during the transition. Hence, the primary objective of this paper is to propose a formal model based on ternary relational semantics that can guide the digital transformation of water distribution networks. The proposed model provides a flexible transformation process while making the system generate reliable data. Additionally, this paper demonstrates the application of the proposed model by developing a proof of concept based on a real-world scenario. [ABSTRACT FROM AUTHOR]

The modern smart grid (SG) is mainly a cyber-physical system (CPS), combining the traditional power system infrastructure with information technologies. SG is frequently threatened by cyber attacks such as False Data Injection (FDI), which manipulates the states of power systems by adding malicious data. To maintain a reliable and secure operation of the smart grid, it is crucial to detect FDI attacks in the system along with their exact location. The conventional Bad Data Detection (BDD) algorithm cannot detect such stealthy attacks. So, motivated by the most recent deep learning (DL) developments and data-driven solutions, a new transformer-based model named XTM is proposed to detect and identify the exact locations of data intrusions in real-time scenarios. XTM, which combines the transformer and long short-term memory (LSTM), is the first hybrid DL model that explores the performance of transformers in this particular research field. First, a new threshold selection scheme is introduced to detect the presence of FDI, replacing the need for conventional BDD. Then, the exact intrusion point of the attack is located using a multilabel classification approach. A formally verified constraints satisfaction-based attack vector model was used to manipulate the data set. In this work, considering the temporal nature of power system, both hourly and minutely sensor data are used to train and evaluate the proposed model in the IEEE-14 bus system, achieving a detection accuracy of almost 100%. The row accuracy (RACC) metric was also evaluated for the location detection module, with values of 92.99% and 99.99% for the hourly and minutely datasets, respectively. Moreover, the proposed technique was compared with other deep learning models as well, showing that the proposed model outperforms the state-of-the-art methods mentioned in the literature. [ABSTRACT FROM AUTHOR]

States create customs unions to accrue consumer welfare gains. Given the incentives to cheat to protect domestic firms from foreign competition, they create regulatory regimes with international courts to manage noncompliance. I develop a formal model that explains how the politics of compliance in regulatory regimes systematically distorts the welfare gains that states accrue from developing customs unions. The model predicts that regulatory regimes are most effective at enforcing compliance (i.e., at reducing trade barriers) in industries with intermediate levels of firm homogeneity in terms of productivity. In highly homogenous industries, regulatory regimes are not effective because noncompliance is minimal enough that litigation is not cost-effective; in highly heterogenous industries, regulatory regimes are not effective because courts, concerned about noncompliance with their rulings, are unlikely to rule against the defendants, deterring the plaintiffs from bringing cases. The model also predicts the downstream consequences for the performance of individual firms and consumer welfare. [ABSTRACT FROM AUTHOR]

Illegal software manipulation is one of the biggest issues in software security. This includes the legally relevant software which are now crucial modules in weight and measuring instruments such as weighbridges. Despite the advancement and complexity of weight and measuring instruments, the inspection methodology is weak and lacks of innovation. The conventional inspection method is merely based on the observation printed certificate of the software. This paper introduces Malaysia Software-Assisted Non-Automatic Weighing Instrument (NAWI) Inspection (MySANI), a method used to enhance the software inspection scheme in legal metrology. MySANI introduces security objects in order to assist and enhance the inspection process. The security evaluation is based on the best practices in IT in metrology, where the attack model on relevant assets of the security objects is simulated for the Attack Probability Tree. The attack tree is verified by integrating formal notation and comparison with finite state transition system domain to verify the correctness properties of the tree design before the model can be further used in a risk analysis procedure within the Attack Probability Tree framework. Results show that the designed attack tree is consistent with the designed simulation. [ABSTRACT FROM AUTHOR]

This study discusses the formal verification of the Worldwide Interoperability for Microwave Access (WiMAX) security protocol. WiMAX security specifications are defined as a security property that must be met by the protocol in a WiMAX network. The security properties that must be met include pseudonymity, information confidentiality, anti-tapping and session key secrecy. Several studies have found several failures to comply with the security properties set by the WiMAX IEEE 802.16-2004 and IEEE 802.16e-2005 standards. Some of the attacks that can occur include jamming, scrambling, DoS attacks, replay attacks, modification of management messages, downgrade attacks, interleaving attacks and other types of security attacks. From some of these attacks there are several solutions to improve security protocols to overcome these attacks so that they can comply with security protocols. Proof of security protocols in the ability to fulfill security properties can be done either formally or informally. The security protocol operational semantic model framework developed by Cas Cremers and Sjouke Mauw is used to carry out formal verification of proposed improvements to the authentication protocol and Privacy and Key Management (PKM) protocol. Modeling the proposed protocol with an operational semantic framework has been able to prove the proposed improvement of the authentication protocol and PKM by using timestamps, SS/BS identity encryption and adding digital signatures or message digest values to ensure authentication is able to meet the specified security properties. [ABSTRACT FROM AUTHOR]

The properties of dynamic interactions in mobile-interactive systems are still difficult to analyze because of the complexity of systems. Thus, we have proposed a new Petri net called the variable petri net (VPN) recently, which specializes in describing dynamic interactions in systems. To make better use of VPN, this article focuses on the model checking method of VPN. It introduces the algorithm to transform a VPN to a Kripke structure that can describe both the system running states and the system connection states in VPN, and the method to transform a property to a temporal logic formula based on VPN and its Kripke structure. The Kripke structure can be optimized by considering the specific property about the system connection states and then be used to perform the targeted verification to the property by using a model checker. A practical example is given to demonstrate the proposed methods. [ABSTRACT FROM AUTHOR]

This paper is devoted to the problems of ontology-based mathematical knowledge management and representation. The main attention is paid to the development of a formal model for the representation of mathematical statements in the Open Linked Data cloud. The proposed model is intended for applications that extract mathematical facts from natural language mathematical texts and represent these facts as Linked Open Data. The model is used in development of a new version of the OntoMath ontology of professional mathematics is described. OntoMath underlies a semantic publishing platform, that takes as an input a collection of mathematical papers in LaTeX format and builds their ontology-based Linked Open Data representation. The semantic publishing platform, in turn, is a central component of OntoMath digital ecosystem, an ecosystem of ontologies, text analytics tools, and applications for mathematical knowledge management, including semantic search for mathematical formulas and a recommender system for mathematical papers. According to the new model, the ontology is organized into three layers: a foundational ontology layer, a domain ontology layer and a linguistic layer. The domain ontology layer contains language-independent math concepts. The linguistic layer provides linguistic grounding for these concepts, and the foundation ontology layer provides them with meta-ontological annotations. The concepts are organized in two main hierarchies: the hierarchy of objects and the hierarchy of reified relationships. [ABSTRACT FROM AUTHOR]

Constitutional monarchies have proved to be resilient, and some have made substantive political interventions even though their positions are mostly hereditary, without granted constitutional channels to do so. This article examines how constitutional monarchs can influence political affairs and what impact royal intervention can have on politics. I argue that constitutional monarchs affect politics indirectly by influencing the preferences of the public who have de jure power to influence political leaders. The analyses herein show that constitutional monarchs do not indiscriminately intervene in politics, but their decisions to intervene reflect the public's preferences. First, constitutional monarchs with little public approval become self-restraining and do not attempt to assert their political preferences. Second, they are more likely to intervene in politics when the public is less satisfied about the incumbent government. These findings are illustrated with historical narratives regarding the political involvement of King Bhumibol Adulyadej of Thailand in the 2000s. [ABSTRACT FROM AUTHOR]

The graphical modeling language GRAFCET is used as a formal specification language in industrial control design. To use these formal specifications for model-driven development of control code it is beneficial to ensure their syntactical and semantic correctness. Therefore in this paper, a detailed meta-model for GRAFCET is presented, which takes so-called terms into account, i.e. logical and arithmetic expressions in conditions and assignments. The meta-model and additionally proposed invariants allow the creation of syntactically correct GRAFCET instances. Based on this, a translation of GRAFCET to Guarded Action Language (GAL) is presented. The resulting transition system in GAL forms the basis for a semantic analysis of the GRAFCET instances by means of model checking in future research. Finally, the models are then employed for automatic code generation in Structured Text.

This work presents formal modeling of Network-on-Chip (NoC) considering detailed functional units of NoC. The intricate modeling of NoC router components like buffer, switch, and arbiter is accomplished using Finite State Machine (FSM). As in the case of a real NoC, parallel execution of these functional units is carried out by maintaining the synchronization between these functional units within a router and between each of the adjacent routers in the presented formal model. Important properties for the correctness of the proposed model are verified using a model checker. Implementing a detailed and a complete NoC model is a memory extensive operation while verifying with a model checker. We have introduced a concept of active windows to verify each router and its communication with the adjacent routers. The correctness of the model is checked by verifying the synchronization between NoC functional units and NoC routers, verifying progress in functional units, and verifying the successful transfer of packets. Verification of starvation freedom in an NoC router is also performed for round-robin arbiter and fixed-priority arbiter. Parallel threads are used in the experiments to reduce the verification time.