Dynamical Arguments Research Articles

Dynamic collective argumentation: Constructing the revision and contraction operators

Collective argumentation has always focused on obtaining rational collective argumentative decisions. One approach that has been extensively studied in the literature is the aggregation of individual extensions of an argumentation framework. However, previous studies have only examined aggregation processes in static terms, focusing on preserving semantic properties at a given time. In contrast, this paper investigates whether decisions remain rational when the preservation process is dynamic, meaning that it can incorporate new information. To address the dynamic nature of collective argumentation, we introduce the revision and contraction operators. These operators reflect the idea that when an individual or a group learns something new by accepting or rejecting an argument, they have to update their collective decision accordingly. Our study examines whether the order of revising individual opinions and aggregating them affects the final outcome, i.e., whether aggregation and revision commute.

Shape, velocity, and exact controllability for the wave equation on a graph with cycle

Exact controllability is proved on a graph with cycle. The controls can be a mix of controls applied at the boundary and interior vertices. The method of proof first applies a dynamical argument to prove shape controllability and velocity controllability, thereby solving their associated moment problems. This enables one to solve the moment problem associated with exact controllability. In the case of a single control, either boundary or interior, it is shown that exact controllability fails.

Digital capabilities to manage agri-food supply chain uncertainties and build supply chain resilience during compounding geopolitical disruptions

PurposeThe agricultural supply chain is susceptible to disruptive geopolitical events. Therefore, agri-food firms must devise robust resilience strategies to hasten recovery and mitigate global food security effects. Hence, the central aim of this paper is to investigate how supply chains could leverage digital technologies to design resilience strategies to manage uncertainty stemming from the external environment disrupted by a geopolitical event. The context of the study is the African agri-food supply chain during the Russian invasion of Ukraine.Design/methodology/approachThe authors employ strategic contingency and dynamic capabilities theory arguments to explore the scenario and conditions under which African agri-food firms could leverage digital technologies to formulate contingency strategies and devise mitigation countermeasures. Then, the authors used a multi-case-study analysis of 14 African firms of different sizes and tiers within three main agri-food sectors (i.e. livestock farming, food-crop and fisheries-aquaculture) to explore, interpret and present data and their findings.FindingsDownstream firms (wholesalers and retailers) of the African agri-food supply chain are found to extensively use digital seizing and transforming capabilities to formulate worst-case assumptions amid geopolitical disruption, followed by proactive mitigation actions. These capabilities are mainly supported by advanced technologies such as blockchain and additive manufacturing. On the other hand, smaller upstream partners (SMEs, cooperatives and smallholders) are found to leverage less advanced technologies, such as mobile apps and cloud-based data analytics, to develop sensing capabilities necessary to formulate a “wait-and-see” strategy, allowing them to reduce perceptions of heightened supply chain uncertainty and take mainly reactive mitigation strategies. Finally, the authors integrate their findings into a conceptual framework that advances the research agenda on managing supply chain uncertainty in vulnerable areas.Originality/valueThis study is the first that sought to understand the contextual conditions (supply chain characteristics and firm characteristics) under which companies in the African agri-food supply chain could leverage digital technologies to manage uncertainty. The study advances contingency and dynamic capability theories by providing a new way of interacting in one specific context. In practice, this study assists managers in developing suitable strategies to manage uncertainty during geopolitical disruptions.

Temperature corrections for coaxial cylindrical viscosity measurement method on molten salt

Modern industrial applications often require accurate measurements of high temperature fluids such as molten salts. However, the commonly used coaxial cylindrical viscosity measurement method has an intrinsic bias when the calibration fluid and test fluid are run at significantly different temperatures due to the thermal expansion of solid container materials. In this study, we take a novel approach by deriving and quantifying the thermal expansion bias, β, for various common container materials using fluid dynamics arguments, thermal expansion data, and empirical methods. To the best knowledge of the authors, this work represents the first quantification of the thermal expansion bias and fills a significant gap in the current understanding. To validate our findings, we conducted an experiment on solar salt and applied the derived thermal expansion correction to the results, comparing them to independent studies. The results highlight the importance of the thermal expansion correction, which increases with rising temperature, particularly in high thermal expansion materials such as stainless steel, which has a bias of ∼6 % at 1000 °C. Our contribution provides valuable insights into the accurate measurement of high temperature fluids and offers a substantial advancement in addressing the thermal expansion bias, setting a new standard for future research in this field.

Analisis Penerokaan terhadap Definisi dan Konsep Landskap Budaya

Many have analyzed “cultural landscape” and its meaning. Some recall the basics of diverse fields, such as “a cultural landscape is a landscape that has been cultivated” or “culture that dwells in a landscape.” The need to decipher “cultural landscape” has drive n research on people’s cultural views of their immediate surroundings. This study suggests cultural landscape research in South East Asia against the backdrop of emerging approaches in cultural landscape research worldwide. Thus, this essay will examine cultural dynamics arguments and hypotheses. This exploratory review and inductive qualitative analysis examined “cultural landscape” studies from the early 19th century to the present. Google Scholar, Science Direct, and other professional education search portals were used to find and examine over fifty papers on local cultural landscapes. To understand cultural landscape studies’ interconnectedness, research results are synthesized and thematized. Therefore, the study provides a concise overview of eight (8) significant fields of study: geography, governance, environmental studies, etymology, tourism, agricultural studies, health studies and technology. Only tourism, ecology, geography, and politics study Indonesia’s cultural landscape. However, despite the abundance of creative and literary creation in Indonesia, little progress has been made in this area. Instead, new findings in domains as diverse as literature, semantics, and etymology are advancing our knowledge of the cultural environment and its effects.

The B-type Binaries Characterisation Programme – II. VFTS 291: a stripped star from a recent mass transfer phase

ABSTRACT Recent studies of massive binaries with putative black hole companions have uncovered a phase of binary evolution that has not been observed before, featuring a bloated stripped star that very recently ceased transferring mass to a main-sequence companion. In this study, we focus on the candidate system VFTS 291, a binary with an orbital period of 108 d and a high semi-amplitude velocity (K1 = 93.7 ± 0.2 km s−1). Through our analysis of the disentangled spectra of the two components, together with dynamical and evolutionary arguments, we identify a narrow-lined star of ∼1.5–2.5 $\, \mathrm{M}_\odot$ dominating the spectrum, and an early B-type main-sequence companion of 13.2 ± 1.5 $\, \mathrm{M}_\odot$. The low mass of the narrow-lined star, and the high mass ratio, suggest that VFTS 291 is a post-mass-transfer system, with the narrow-lined star being bloated and stripped of its hydrogen-rich envelope, sharing many similarities with other recently discovered stripped stars. Our finding is supported by our detailed binary evolution models, which indicate that the system can be well explained by an initial configuration consisting of an 8.1 $\, \mathrm{M}_\odot$ primary with an 8 $\, \mathrm{M}_\odot$ companion in a 7 d orbital period. While some open questions remain, particularly concerning the surface helium enrichment of the stripped star and the rotational velocity of the companion, we expect that high-resolution spectroscopy may help reconcile our estimates with theory. Our study highlights the importance of multi-epoch spectroscopic surveys to identify and characterize binary interaction products, and provides important insights into the evolution of massive binary stars.

Constrained stochastic differential games with Markovian switchings and additive structure: The total expected payoff

The main objective of this work is to give conditions for the existence of Nash equilibria for a nonzero-sum constrained stochastic differential game with additive structure and Markovian switchings. In this type of game, each player is interested only in maximizing their finite-horizon total payoff when an additional cost function of the same type is required to be dominated above by another function (in particular, by a constant). The dynamic system for this game is controlled by two players and evolves according to a Markov-modulated diffusion (also known as switching diffusions or piecewise diffusion or diffusion with Markovian switchings). Given that, each player has to solve an optimization problem with constraints. The existence of a Nash equilibrium is thus proved using the Lagrange multipliers approach combined with standard dynamic programming arguments. The Lagrange approach allows the transformation of a constrained game into an unconstrained game. Therefore, this work gives conditions under which a Nash equilibrium for the unconstrained stochastic differential game is also a Nash equilibrium for the corresponding nonzero-sum constrained stochastic differential game. The theory developed here is illustrated by a pollution accumulation problem with two players. Therein, the evolution is governed by a linear stochastic differential equation with Markovian switching, and the decay pollution rate depends on a Markov chain.

Modeling Graph Neural Networks and Dynamic Role Sorting for Argument Extraction in Documents

The existing methods for document-level event extraction mainly face two challenges. The first challenge is effectively capturing event information that spans across sentences. The second challenge is using predefined orders to extract event arguments while disregarding the dynamic adjusting of the order according to the importance of argument roles. To address these issues, we propose a model based on graph neural networks which realizes the semantic interaction among documents, sentences, and entities. Additionally, our model adopts a dynamic argument detection strategy, extracting arguments depending on their number in correspondence with each role. The experimental results confirm the outperformance of our model, which surpasses previous methods by 7% and 1.9% in terms of an F1 score.

Constraints on Evolutionary Timescales for M Dwarf Planets from Dynamical Stability Arguments

The diversity of dynamical conditions among exoplanets is now well established. Yet, the relevance of orbital dynamical timescales to biological evolutionary timescales is poorly understood. Given that even minor orbital changes may place significant pressure on any organisms living on a planet, dynamical sculpting has important implications for the putative evolution of life. In this manuscript, we employ a Monte Carlo framework to investigate how a range of exoplanetary dynamical sculpting timescales affects timescales for biological evolution. We proceed with minimal assumptions for how dynamical sculpting proceeds and the emergence and persistence of life. We focus our investigation on M dwarf stars, the most common exoplanetary hosts in the Milky Way. We assign dynamical statuses, dependent on stellar age, to a suite of planetary systems, varying the rate of dynamical disruption within limits that are consistent with present-day planet demographics. We then simulate the observed yield of planets according to the completeness of NASA's Kepler and TESS missions, and investigate the properties of these samples. With this simplified approach, we find that systems hosting multiple transiting planets ought to have, on average, shorter dynamically uninterrupted intervals than single-transiting systems. However, depending upon the rate of dynamical sculpting, planets orbiting older stars will exhibit the opposite trend. Even modest constraints on stellar age would help identify older stars for which this holds. The degree of these effects varies, dependent upon both the intrinsic dynamical demographics of exoplanets and whether we consider planets detected by NASA’s Kepler or TESS missions.

Die Problematik des relationalen Elends in sittlicher Sicht

For a moral-theological encounter with the issue of suffering, there is necessary to make a distinction within suffering. A distinction is made between pain and misery and the moral role of man. Liberation Theology dealt with the situation of contextual misery. This theology offers new possibilities for analyzing suffering from the perspective of the kingdom of God and identifying resources to combat it. The points of view of liberation theology caused dynamic discussions and arguments in society and the Church: initially they were partially rejected, later, however, accepted. This issue of social misery is also the focus of moral theology.

Selecting embedding delays: An overview of embedding techniques and a new method using persistent homology.

Delay embedding methods are a staple tool in the field of time series analysis and prediction. However, the selection of embedding parameters can have a big impact on the resulting analysis. This has led to the creation of a large number of methods to optimize the selection of parameters such as embedding lag. This paper aims to provide a comprehensive overview of the fundamentals of embedding theory for readers who are new to the subject. We outline a collection of existing methods for selecting embedding lag in both uniform and non-uniform delay embedding cases. Highlighting the poor dynamical explainability of existing methods of selecting non-uniform lags, we provide an alternative method of selecting embedding lags that includes a mixture of both dynamical and topological arguments. The proposed method, Significant Times on Persistent Strands (SToPS), uses persistent homology to construct a characteristic time spectrum that quantifies the relative dynamical significance of each time lag. We test our method on periodic, chaotic, and fast-slow time series and find that our method performs similar to existing automated non-uniform embedding methods. Additionally, n-step predictors trained on embeddings constructed with SToPS were found to outperform other embedding methods when predicting fast-slow time series.

Plume driven plate motion changes: New insights from the South Atlantic realm

Plate motion changes are increasingly well documented in the geologic record. Directional plate motion changes, in particular, provide powerful constrains on plate tectonic torques, because they require a change in plate boundary torques, basal shear stresses or both that can be spatially located. Over the past years a pressure driven, so-called Poiseuille, flow model for upper mantle flux in the asthenosphere has gained increasing geodynamic attention—for a number of fluid dynamic arguments. This conceptually simple model makes a powerful testable prediction: Poiseuille flow induced plate motion changes should coincide with interregional scale mantle convection induced dynamic topography around the origin of the Poiseuille source. Here we focus on the South American plate, which undergoes two distinct directional changes in motion in the Paleogene. During this time period there is evidence for Paleocene and Eocene/Oligocene high dynamic topography in South America and Africa, which we infer by mapping geological hiatus (i.e., gaps in the stratigraphic record). This suggests a high-pressure source in the upper mantle in the South Atlantic. We apply Poiseuille/Couette flow models to show that the Sierra Leone and Tristan plumes are suitably located to provide the torque to initiate these plate motion changes. Our modeling results are entirely consistent with changes in proxy elevation in the African and South American continents at those times. Moreover, they imply that it is possible to locate torques from sources of active upper mantle flow that can explain directional plate motion changes, and identify them for the South American plate with geological features such as the Sierra Leone and Tristan plumes.

The Dynamic Strategy of Common Sense Against Radical Revisionism

Common-sense philosophers typically maintain that common-sense propositions have a certain kind of epistemic privilege that allows them to evade the threats of skepticism or radical revisionism. But why do they have this special privilege? In response to this question, the “Common-Sense Tradition” contains many different strands of arguments. In this paper, I will develop a strategy that combines two of these strands of arguments. First, the “Dynamic Argument” (or the “starting-point argument”), inspired by Thomas Reid and Charles S. Peirce (but which will be strengthened with the help of Gilbert Harman’s epistemology of belief revision). Second, G.E. Moore’s “greater certainty argument” (interpreted along the lines of Soames’ and Pollock’s construal). This combined strategy, I will argue, is the strong core of Common-Sense Philosophy, and relies on extremely modest and widely held assumptions.

LLPS vs. LLCPS: analogies and differences.

We compare the process of Liquid-Liquid Phase Separation (LLPS) of flexible macromolecular solutions, with the Liquid-Liquid Crystalline Phase Separation (LLCPS) of semiflexible polymers and rigid filamentous colloids, which involves the formation of a liquid phase that possesses a directional alignment. Although the observed phase separation follows a similar dynamic path, namely nucleation and growth or spinodal decomposition separating two phases of dilute and concentrated compositions, the underlying physics that defines the theoretical framework of LLCPS is completely different from the one of LLPS. We review the main theories that describe the phase separation processes and relying on thermodynamics and dynamical arguments, we highlight the differences and analogies between these two phase separation phenomena, attempting to clarify the inner mechanisms that regulate those two processes. A particular focus is given to metastable phases, as these intermediate states represent a key element in understanding how phase separation works.

Actuator Scheduling for Linear Systems: A Convex Relaxation Approach

In this letter, we investigate the problem of actuator scheduling for networked control systems. Given a stochastic linear system with a number of actuators, we consider the case that one actuator is activated at each time. This problem is combinatorial in nature and NP-Hard to solve. We propose a convex relaxation to the actuator scheduling problem, and use the relaxed solution as a <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">reference</i> to design an algorithm for solving the original scheduling problem. Using dynamic programming arguments, we provide a suboptimality bound of our proposed algorithm. Furthermore, we show that our framework can be extended to incorporate multiple actuator scheduling at each time and actuation costs. A simulation example is provided, which shows that our proposed method outperforms a random selection approach and a greedy selection approach.

Underrepresentation, Quotas and Quality: A dynamic argument for reform

Underrepresentation, Quotas and Quality: A dynamic argument for reform

Underrepresentation, Quotas and Quality: A Dynamic Argument for Reform

Underrepresentation, Quotas and Quality: A Dynamic Argument for Reform

Optimal consumption and life insurance under shortfall aversion and a drawdown constraint

This paper studies a life-cycle optimal portfolio-consumption problem when the consumption performance is measured by a shortfall aversion preference under an additional drawdown constraint on consumption rate. Meanwhile, the agent also dynamically chooses her life insurance premium to maximize the expected bequest at the death time. By using dynamic programming arguments and the dual transform, we solve the HJB variational inequality explicitly in a piecewise form across different regions and derive some thresholds of the wealth variable for the piecewise optimal feedback controls. Taking advantage of our analytical results, we are able to numerically illustrate some quantitative impacts on optimal consumption and life insurance by model parameters and discuss their financial implications.

Approximating stability for applied argument-based inquiry

• Detecting stability is a CoNP-complete problem in dynamic argumentation. • A claim is stable if more information cannot change its justification status. • We propose a sound and polynomial approximation algorithm for estimating stability. • We provide empirical and theoretical analyses of the algorithm’s performance. • The algorithm is applied in three use cases at the Netherlands Police. In argument-based inquiry, agents jointly construct arguments supporting or attacking a topic claim to find out if the claim can be accepted given the agents’ knowledge bases. While such inquiry systems can be used for various forms of automated information intake, several efficiency issues have so far prevented widespread application. In this paper, we aim to tackle these efficiency issues by exploring the notion of stability: can additional information change the justification status of the claim under discussion? Detecting stability is not tractable for every input, since the problem is CoNP-complete, yet in practical applications it is essential to guarantee efficient computation. This makes approximation a viable alternative. We present a sound approximation algorithm that recognises stability for many inputs in polynomial time and discuss several of its properties. In particular, we show that the algorithm is sound and identify constraints on the input under which it is complete. As a final contribution of this paper, we describe how the proposed algorithm is used in three different case studies at the Netherlands Police.

Shape, Velocity, and Exact Controllability for the Wave Equation

A new method to prove exact controllability for the wave equation is demonstrated and discussed on several examples. The method of proof first uses a dynamical argument to prove shape controllability and velocity controllability, thereby solving their associated moment problems. This enables one to solve the moment problem associated to exact controllability.