Formal Model Research Articles

A strategy to what end? “The strategy of model building in population biology” in its programmatic context

Abstract“The Strategy of Model Building in Population Biology” published by Richard Levins in 1966 has been cited over 2500 times. For a paper concerned with modeling approaches in population biology a surprisingly large part of the attention. The Strategy received comes from history and philosophy of biology, and specifically from accounts on model and model formulation. The Strategy is an unusual paper; it presents neither new data nor a new formal model; at times it reads like a manifesto for some modeling approach, without specifying which broader program that approach intends to support. When these peculiarities of The Strategy are even mentioned, the philosophical literature tends to explain them away by invoking Levins’ Marxist commitments. In contrast, I argue that those peculiarities can be explained by examining the programmatic purpose of the paper; starting from his doctoral work, Levins was trying to establish a research program meant to account for the relations between fitness and environment in different terms than the prevalent lock-and-key view. My paper brings that program back to the discussion, explains its relation to competing approaches and examines Levins’ approach to modeling in light of that context

Expertise and Inequality Amid Environmental Crisis: A View from the Yukon-Kuskokwim Delta

ABSTRACT Scientific expertise is crucial for responding effectively to environmental crises. Nevertheless, under conditions of political inequality, expert policy making can inhibit policy solutions by altering incentives of powerful interest groups. This is the situation facing the predominantly Alaska Native communities of the Yukon-Kuskokwim Delta, which have long relied on salmon for subsistence and are now experiencing a collapse of the salmon population. Scientific evidence indicates that climate change is a primary cause, and experts therefore have opposed demands by Native subsistence fishers for ameliorative measures—especially restricting pollock fishing—as likely to be ineffective. However, this approach eliminates incentives for the influential pollock industry to support policies to address the salmon crisis, including climate-change mitigation. This article presents a simple formal model that demonstrates these incentive effects. This argument contributes to theories of business power and shows how expert policy making can inadvertently force marginalized communities to bear the burden of climate change.

Mentoring in the context of music teacher education: A systematic review

The preparation of music teachers represents a key factor within the educational framework. In a world in constant evolution, the need to integrate new training proposals that cater to different environments is of vital importance to strengthen music education. The aim of this study is to analyze the use of mentoring in the context of music teaching through a systematic review using PRISMA. Among the results, the main areas addressed by mentoring are observed, being centered around professional development and the accompaniment of both students and teachers who are new to teaching. The profile of the participants in the mentoring relationship (mentor-mentee) is detailed in the systematic review, being the formal models of mentoring, linked to an institution, the most widespread throughout the article. Among the main conclusions, the prominence of the USA in the research and development of mentoring programs is noted and the positive impact of mentoring in both formal and informal contexts is highlighted, emphasizing individualized and group mentoring for professional and personal development in higher education.

Scalar/spinor cosmological model and covariant formalism

Scalar/spinor cosmological model and covariant formalism

The Prenuptial Agreement of Business Spouses: Guarantees of Respect for Mutual Interests and Protection of the Rights of the Parties

Introduction: in the light of modern socio-economic realities, an urgent problem is the effective protection of the property interests and rights of spouses who own a family business. The conclusion of a prenuptial agreement provides spouses who have a family business and are parties to the prenuptial agreement with the opportunity to reduce financial risks and provide themselves with additional legal protection in the event of termination of the marital relationship. The inclusion of legally verified contractual structures in a prenuptial agreement is very effective in preventing future conflicts between spouses who own a joint business. Purpose: to reveal the legal content of the prenuptial agreement concluded between spouses who own a joint business in the system of contractual structures and to develop recommendations for improving the contractual regulation. Objectives: to identify conflicts related to the legal guarantees of respect for mutual interests of spouses who have a family business and are parties to a prenuptial agreement; to identify contractual structures used to minimize conflicts between the subjects of a prenuptial agreement; and to develop a conceptual model for concluding a prenuptial agreement between spouses who own a joint business remotely via the Internet. Methods: the methodological framework for the research is based on the general scientific methods: systematic analysis, abstraction, and the dialectical method, as well as a set of specific scientific methods: structural and functional, formal legal, comparative law, forecasting, and modeling. Results: it is proposed to amend Art. 11 of Federal Law No. 193-FZ dated July 27, 2010, “On an Alternative Dispute Settlement Procedure with the Participation of an Intermediary (Mediation Procedure),” supplementing its paragraph 8; in the context of the effective implementation of the concept of “Electronic State,” the Federal Notary Chamber it is proposed to develop, test, and implement a virtual assistant based on artificial intelligence technologies, which will function not only on the Federal Notary Chamber website but also on the online resources of the notary chambers of the constituent entities of the Russian Federation. Conclusions: it is recommended to normalize the mediation procedure for spouses who have a family business and are parties to a prenuptial agreement through information and communication technologies; as part of the implementation of the concept of “Electronic State,” the Federal Notary Chamber should develop, test, and implement a virtual assistant (“chatbot”) based on artificial intelligence, which will be available not only on the Federal Notary Chamber website but also on the websites of notary chambers of the constituent entities of the Russian Federation, and at the request of users, including spouses who have a joint family business, it will perform an advisory function when drafting a prenuptial agreement.

Ostracism in Japan

Abstract Informal social sanctions such as ostracism are the primary means of controlling deviance in communities. Formal legal sanctions are a costly back-up. Yet outside of university laboratories, studies of ostracism barely exist. We examine legal cases brought by targets of ostracism in Japan, encompassing nearly all the non-trivial reported opinions. The cases do not involve villagers who actually offended their community. Instead, most plaintiffs are victims of opportunistic ostracism, where ostracism is used to extort property, hide community-wide malfeasance, or harass rivals. We explore carefully the non-random character of the disputes and provide a formal model in the annex. We conclude that typical plaintiffs in these lawsuits are not seeking to harness the government's coercive power. Instead, they bring suit for the informational role of courts, aiming to have the court publicly certify that they did not misbehave, contrary to what ostracism might be thought to imply. This analysis contributes to the growing body of legal scholarship on social norms and the role of the courts as informational intermediaries.

Ultra-Short Pulses Laser Heating of Dielectrics: A Semi-Classical Analytical Model.

Femtosecond laser pulses are currently regarded as an emerging and promising tool for processing wide bandgap dielectric materials across a variety of high-end applications, although the associated physical phenomena are not yet fully understood. To address these challenges, we propose an original, fully analytical model combined with Two Temperatures Model (TTM) formalism. The model is applied to describe the interaction of fs laser pulses with a typical dielectric target (e.g., Sapphire). It describes the heating of dielectrics, such as Sapphire, under irradiation by fs laser pulses in the range of (1012-1014) W/cm2. The proposed formalism was implemented to calculate the free electron density, while numerical simulations of temperature field evolution within the dielectrics were conducted using the TTM. Mathematical models have rarely been used to solve the TTM in the context of laser-dielectric interactions. Unlike the TTM applied to metals, which requires solving two heat equations, for dielectrics the free electron density must first be determined. We propose an analytical model to solve the TTM equations using this parameter. A new simulation model was developed, combining the equations for non-equilibrium electron density determination with the TTM equations. Our analyses revealed the non-linear nature of the physical phenomena involved and the inapplicability of the Beer-Lambert law for fs laser pulse interactions with dielectric targets at incident laser fluences ranging from 6 to 20 J/cm2.

Model Checking Spatial Reachability Specifications of Public Transport Networks

Well-designed spatial configurations of public transport stops and routes in big cities contribute to enhancing daily travel services for citizens, effectively mitigating traffic congestion, and addressing other pertinent challenges. When examining spatial layouts of public transport networks (PTNs), various reachability demands between stops or urban Points of Interest (POIs) are crucial issues should be firstly taken into account. Existing methods to investigate spatial reachability properties of PTNs generally need to construct some evaluation functions, or survey reachability metrics through some network analysis techniques. These methods are often impractical, as the functional relations always cannot be accurately defined, or some global network metrics cannot provide explicit evidences for PTN layout planning or optimization.In this paper, we introduce spatial model checking techniques to the formal verification of the reachability specifications of PTN to guarantee the rationality of PTN layout. First, we extend closure space structure by incorporating attribute labeling functions and logical propositions for public transport stops and routes to develop a formal spatial verification model for PTN spatial layout. Second, we propose several novel reachability operators based on the logical operators of the Spatial Logic for Closure Space (SLCS) to facilitate the logical characterization of reachability specifications. Third, we perform the verification of the transformed reachability formulas by the spatial model checker topochecker. Examples demonstrate the effectiveness of our approach and indicate that it can perform automatic, descriptive and comprehensible verification of the reachability properties PTN layouts.

Ensuring the Correctness and Reliability of CBPS System Using Event‐B

ABSTRACTDuring the early phases of software system development, error detection can be challenging due to the complexity of both the requirements and the operating environments. This paper advocates for the utilization of formal modelling and verification throughout the first phases of systems development to promptly detect and correct errors. The formalism employed throughout is Event‐B, which is backed by the Rodin toolset. To conquer requirements complexity, the frameworks of set theory and first‐order logic are employed, which provide the necessary tools for formalizing and analysing the properties and behaviours associated with Event‐B. Also, we detail the way in which modelling may be used to achieve abstraction, as well as the way in which refinement can be used to manage complexity through layering. Furthermore, we emphasize the significance of model validation and verification in improving the precision of formal models and requirements in IoT communication systems. The model is exemplified using a Content‐Based Publish Subscribe System (CBPS), with a special emphasis on a fire alarm system as a motivating example.

Correlative Activation Free Energy (CAFE) Model: Application to Viscous Processes in Inorganic Oxide Glass-Formers

We explore the concept of correlative activation free energy (CAFE) for the analysis and interpretation of viscosity data of a collection of 847 inorganic oxide glass formers that exhibit various degrees of non-Arrhenius behavior. The CAFE model formalism is strictly based on transition state theory and accounts for the variation in the activation barrier for the viscous dissipation due to the structural evolution the system undergoes upon traversing the glass transition regime. Thus, fitting parameters are meaningful in a statistical thermodynamic context. Compared to the VFT and MYEGA equations, fits using the CAFE model are more robust when extrapolating to infinite temperature because the latter encodes non-enthalpic contributions to the rate coefficient more realistically. The CAFE model-based analysis reveals a strong connection between melt fragility and the degree of change in the potential energy landscape with temperature. Accordingly, while the average ground-state potential energy of the glass forming liquid gradually increases with temperature, the energy of the activated state remains relatively invariant. Our analysis also allows one to estimate the number of atoms involved in the viscous relaxation process, which ranges from approximately 10 to 50 atoms for the oxide glass formers studied. We observe that thermally activated dynamic phenomena exhibited by glassy networks, such as the mixed alkali effect, persist into the supercooled liquid state.

Optimizing Traveler Behavior Between MADINA and JEDDA Using UPPAAL Stratego: A Stochastic Priced Timed Games Approach

This study looks at how travelers move between MADINA and JEDDA, using the UPPAAL Stratego tool to tackle the complexities of urban mobility. As cities grow, effective transportation planning becomes more challenging. Travelers have three options: car, bus, and train. The choices for car and bus travel are impacted by traffic conditions, which can vary between heavy and light, affecting both travel time and cost. We propose a detailed mathematical model that captures all possible scenarios related to these travel options, incorporating the uncertainties of real life. This allows us to simulate different traffic situations. By using UPPAAL Stratego, we evaluate three strategies: the Safe Strategy, which minimizes risk; the Fast Strategy, which aims to reduce travel time; and the Fast and Safe Strategy, which seeks a balance between speed and safety. This paper starts with an introduction to the Stochastic Priced Timed Games approach, highlighting its relevance in modeling dynamic travel environments. We then provide an overview of UPPAAL Stratego, showcasing its abilities in generating, optimizing, and comparing strategies. Next, we outline our mathematical model, explaining the assumptions, parameters, and data sources we used. Our simulation results illustrate how each strategy performs under different conditions, shedding light on traveler preferences and behaviors. The findings underscore the significance of accounting for traffic variability in travel planning and offer important insights for urban transportation policies aimed at improving the traveler experience and optimizing resource use. Additionally, we emphasize the theoretical contributions of our model by demonstrating its applicability to real-world scenarios and its potential to inform future research in urban mobility optimization. Ultimately, this research adds to the growing knowledge of smart transportation systems, demonstrating how formal mathematical modeling can address complex real-world challenges and inform future urban mobility strategies.

Awareness Revision and Belief Extension

ABSTRACT What norm governs how an agent should change their beliefs when they encounter a completely new possibility? Orthodox Bayesianism has no answer, as it takes all learning to involve updating prior beliefs. A partial proposal is Reverse Bayesianism, which mandates the preservation of ratios of prior probabilities, but it faces counterexamples introduced by Mahtani (2021). I propose to separate awareness growth into two stages: awareness revision and belief extension. I argue that Mahtani’s cases highlight that we need to theorize awareness revision before we can define a proposal for belief extension, such as Reverse Bayesianism. I provide a formal model of awareness revision which makes explicit how propositions are distinguished within awareness states and identified across them. Reformulating Reverse Bayesianism to take input from my model allows it to navigate Mahtani-style cases. My model leaves open how agents choose to identify propositions across awareness states, and I propose that they ought to do so conservatively: preserving undisturbed prior reasoning about the structure of their awareness. I then spell out this proposal in a special case. This is a partial proposal, and I close with a discussion of how to elaborate on it and how to advance research into awareness revision.

New trends in didactic research in university mathematics education

AbstractRecent research in university mathematics education has moved beyond the traditional focus on the transition from secondary to tertiary education and students' understanding of introductory courses such as pre-calculus and calculus. There is growing interest in the challenges students face as they move into more advanced mathematics courses that require a shift toward formal reasoning, proof, modeling, and problem-solving skills. This survey paper explores emerging trends and innovations in the field, focusing on three key areas: innovations in teaching and learning advanced mathematical topics, transitions between different levels and contexts of mathematics education, and the role of proof and proving in advanced university mathematics. The survey reflects the evolving landscape of mathematics education research and addresses the theoretical and practical challenges of teaching and learning advanced mathematics across various contexts.

Modeling collaborative memory with SAM.

While humans often encode and retrieve memories in groups, the bulk of our knowledge of human memory comes from paradigms with individuals in isolation. The primary phenomenon of interest within the relatively new field of collaborative memory is collaborative inhibition: the tendency for collaborative groups to underperform in free recall tasks compared with noncollaborative groups of the same size. This effect has been found in a variety of materials and group compositions. However, most research in this field is led by verbal conceptual theories without guidance from formal computational models. We present a framework to scale the Search of Associative Memory model (SAM) to collaborative free recall paradigms with multiple models working together. Multiple SAM models recalling together naturally produce collaborative inhibition when the group members use recalls by the group as cues to retrieve from memory, strongly supporting the "retrieval disruption" hypothesis. This work shows that SAM can act as a unified theory to explain both individual and collaborative memory effects and offers a framework for future predictions of scaling to increased group sizes, shared knowledge, and factors facilitating the spread of false memories in groups.

Refining the Scrum Paradigm: A Comprehensive Study of Software Development Practices (2020-2023)

This article presents a complex vision on software production practices aimed at enhancing the Scrum methodology within software project management. The recommended best practices are closely aligned with contemporary trends in the IT sector, including the total digitalization and virtualization of production processes, the transition to fully remote software development models, the incorporation of artificial intelligence technologies, and the implementation of cost-effective models in team organization. The modifications to software production processes discussed herein are grounded in research conducted between 2020 and 2023, encompassing insights from leading Russian, European, and global IT companies. This research underscores a significant transformation in IT business practices, reflecting a shift towards new benchmarks for Scrum team efficiency. These benchmarks emphasize the data-driven formalization of production models, automation facilitated by AI tools, and noticeable cost optimization within engineering teams, which collectively align with the evolving demands of the modern IT landscape. The article details a series of management strategies designed to adapt to these shifts, including the formalization of sprint goals and processes within Scrum, management of technical debt, and the cost-efficient organization of development teams.

Legislative communication and power: measuring leadership in the U.S. House of Representatives from social media data

Abstract Control over the legislative messaging agenda has important political, electoral and policy consequences. Existing models of congressional agenda-setting suggest that national polarization drives the agenda. At the same time, models of home style and formal models of leadership hypothesize that legislators shift their messaging as they balance coordination and information problems. We say the coordination problem dominates when conditions incentivize legislators to agree on the same message rather than fail to reach consensus. Conversely, the information problem is said to dominate in circumstances where legislators prefer to say nothing at all rather than reach consensus on the wrong political message. Formal theories predict that when coordination problems are pressing, legislative members follow the policy positions of party leaders. When their party’s information problem is acute, party members instead rely on the wisdom of the caucus to set the party’s agenda. To test these theories, we analyze the Twitter accounts of U.S. House members with a Joint Sentiment Topic model, generating a new understanding of House leadership power. Our analyses reveal complex leader-follower relationships. Party leaders possess the power to substantially affect the propensity of rank-and-file members to discuss topics, especially when the coordination problem dominates; these effects are pronounced even when coordination problems are pressing. That said, when the underlying politics are unclear, rank-and-file members exert influence on the discussion of a topic because the information problem is more acute. At the same time and for these uncertain topics, leadership influence decreases, consistent with theory. We show these results are robust to the underlying dynamics of contemporary political discussion and context, including leading explanations for party leadership power, such as national polarization.

On formal modeling, analysis and optimization of reconfigurable manufacturing systems

ABSTRACT This paper deals with the formal specification and multi-objective optimization of reconfigurable manufacturing systems (RMSs). RMSs are characterized by their dynamic structure, crucial for responding to functional variations, adjusting production capacity and overcoming operational dysfuntions promptly and cos-effectively. The effective utilization of this dynamic capability depends on thorough study and optimization of RMS configurations. To tackle this challenge, a novel formalism called genetic reconfigurable object nets (Gen-RONs) is introduced. Gen-RONs formalism integrates the modeling, verification and reconfiguration capabilities of reconfigurable object nets with advanced multi-objective techniques from genetic algorithms. Within Gen-RONs, Petri nets serve to: (i) encode RMS configurations, (ii) manage RMS scheduling and (iii) employ graph transformation theory rules as genetic algorithm operators for real-time system reconfiguration. Thus, Gen-RONs formalism provides a robust framework for optimizing RMSs using genetic algorithms. To ensure deadlock-free RMS configurations, Gen-RONs incorporate a binary tree-based technique. Furthermore, Taguchi’s method is employed to fine-tune genetic algorithm parameters. The contribution of this paper is demonstrated through a case study involving an RMS and the widely used genetic algorithm NSGA-II. Significant gains in terms of the number of solutions (i.e. configurations) and the criteria values are achieved.

"We Want to be There to Support … Do We Have the Capacity to Do That?" Current Priorities and Challenges in School Social Work.

While adolescent mental health needs have continued to rise, schools have become a central location for adolescents seeking support for mental health needs, and approximately 96% of public schools in the United States report providing some form of mental health care to students. This study aims to explore school social workers' current challenges and priorities in their roles. Qualitative focus groups with current school social workers in Virginia (N = 16) were conducted for this study. Participants worked in middle and high schools for a minimum of 3 years across the state. Braun and Clarke's steps for thematic analysis were used to guide coding and themes. The current study found 3 primary themes: (1) role confusion due to vast scope of responsibilities within their schools; (2) a disconnect between desired roles and assigned roles and responsibilities; and (3) lack of formal model of service provision. Focus should be placed on the integration of current models of school social work practice to ensure the effective utilization of their services. The study reveals important information regarding the current and future state of school social work practice.

X-RMTV: An Integrated Approach for Requirement Modeling, Traceability Management, and Verification in MBSE

Formal requirements modeling and traceability management are essential for effectively implementing Model-Based Systems Engineering (MBSE). However, few studies have explored the integration of requirement modeling, traceability management, and verification within MBSE-based systems engineering methodologies. Moreover, the predominant modeling language for MBSE, SysML, lacks sufficient capabilities for requirement description and traceability management and for depicting physical attributes and executable capabilities, making it challenging to verify functional and non-functional requirements collaboratively. This paper proposes an integrated approach for requirement modeling, traceability management, and verification, building on the previously proposed integrated modeling and the simulation language called X language. Our contributions primarily include defining the ReqXL specification for MBSE-oriented requirement modeling based on X language, proposing an algorithm for automatically generating requirement traces, and an integrated framework for requirements modeling, traceability management, and verification was developed by combining the X language with ReqXL. These functionalities were customized on the self-developed integrated modeling and simulation platform, XLab, which is specifically tailored for the X language. Furthermore, we showcase the efficacy and promise of our approach through a case study involving the design of an aircraft electrical system.

Mathematical Model of Horizontal Track Conflict Prevention Algorithm in Detect-and-Avoid Framework

With the proliferation of Unmanned Aerial Vehicle (UAV) technology, the demand for effective collision avoidance technology has intensified. The DAIDALUS algorithm, devised by NASA Langley Research Center under the Detect-and-Avoid (DAA) framework, provides conflict prevention bands for remotely piloted UAVs navigating in intricate airspace. The algorithm computes the bands in two distinct phases: Conflict and Recovery. The formal model for both phases has been established and implemented through iterative programming approaches. However, the mathematical model remains incomplete. Therefore, based on the model, this paper proposes the mathematical model for the two phases of the horizontal track conflict prevention algorithm. Firstly, Cauchy’s inequality is proposed to formulate the model that addresses trajectory conflicts considering the UAV non-instantaneous maneuvering dynamics model, and then a prudent maneuvering strategy is designed to optimize the model for the recovery phase. Finally, the execution procedure of the algorithm within the two-stage mathematical model is also detailed. The results demonstrate that the proposed model achieves a higher precision in the preventive bands, implements an effective collision avoidance strategy, and consistently aligns with the DAIDALUS model while offering a larger buffer time or distance. This work theoretically validates the formal model of the DAIDLAUS algorithm and provides insights for further refinement.