Explicit Theory Research Articles

Explicit Commutativity for Lamé Linear Time‐Varying Differential Systems

ABSTRACTThis article studies the commutativity and sensitivity of the Lamé linear time‐varying systems (LTVSs), and investigates the effects of disturbances on such systems. The commutative pair for the Lamé LTVS of order is found, that is, a new Lamé LTVS of order is derived using the explicit commutative theories for zero initial conditions (ICs). For the case of nonzero ICs, the commutativity between the connected input–output of Lamé systems and is studied. New and simple explicit commutative theories and conditions for second‐order LTVSs are derived, simplifying the use of commutativity for practical and industrial scenarios. These findings enable us to analyse the commutativity, sensitivity, robustness and stability of Lamé systems, and to determine the effects of disturbances. The explicit results presented in this article are supported by simulations and verified by examples and constitute a significant contribution to science and engineering applications.

EXPRESS: The lexical boost is not an automatic part of sentence production: Evidence from Japanese structural priming.

The lexical boost is an increase in structural priming with overlapping elements like verbs. Residual activation priming theories argue that the boost is an automatic side effect of sentence planning. In contrast, explicit memory theories of the boost argue that it is the result of a non-automatic explicit memory retrieval. These theories were contrasted in Japanese by including a prime memory task in a structural priming study. Structural priming was found for both datives and passives, but no lexical boost was found and one possible reason was that explicit memory for the prime structure was weak. In a follow-up study, priming was found in a sentence completion task, but there was no lexical boost. The existence of abstract priming and the lack of a lexical boost in these studies falsifies theories that argue that verb overlap automatically creates a boost under conditions that exhibit abstract priming.

B - 115 How Training Conditions Impact Performance on a Theoretically-Derived Learning Instrument

Abstract Objective Few neuropsychological measures were developed using an explicit theory that accounts for individual performance. We developed a novel associative learning measure to address this limitation and investigated whether training conditions could influence accuracy and response time. Methods Fifty young, community-dwelling adult participants completed the novel relational learning task, which explicitly trained two stimulus pairs (A- > B, A- > C) and involved a single common stimulus. Participants identify six unique relationships between stimuli: trained relations (A- > B, A- > C), mutually entailed relations (B- > A, C- > A), and combinatorial relations (B- > C, C- > B). Participants were randomly assigned to a congruent (A is opposite B, A is opposite C) or incongruent (A is opposite B, B is the same as C) training condition and completed the procedure when stimuli were observably (e.g., color-coded shapes) or arbitrarily related (e.g., letters). Results Comparisons of accuracy between training conditions using Bayesian independent samples t-tests found moderate evidence of no reliable difference between training groups when stimuli were observably related (BF01 = 3.4, δ = 0.06) and arbitrarily related (BF01 = 3.5, δ = 0.03). Comparisons of response time found strong evidence that participants took longer to identify relations when receiving incongruent training when the stimuli were visually related (BF10 = 38.8, δ = 0.9) but inconclusive evidence when the stimuli were arbitrarily related (BF10 = 1.5, δ = 0.49) (See Table 1). Conclusion These findings suggest that manipulating training conditions does not appreciably impact the ability to identify relationships between stimuli accurately. However, training appears to increase the response time needed to identify visibly related stimuli accurately. While this is a promising theoretically-derived learning paradigm, further research is required for validation in clinical practice.

Nonlinear chiral forms in the Sen formulation

The Sen formulation for chiral (2p)-form in 4p+2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$4p+2$$\\end{document} dimensions describes a system with two separate sectors, one is physical while the other is unphysical. Each contains a chiral form and a metric. In this paper, we focus on the cases where the self-duality condition for the unphysical sector is linear while for the physical sector can be nonlinear. We show the decoupling at the Hamiltonian and Lagrangian levels. The decoupling at the Hamiltonian level follows the idea in the literature. Then by an appropriate field redefinition of the corresponding first-order Lagrangian, the separation at the Lagrangian level follows. We derive the diffeomorphism of the theory in the case where the chiral form in the physical sector has nonlinear self-dual field strength and couples to external (2p+1)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(2p+1)$$\\end{document}-form field. Explicit forms of Sen theories are also discussed. The Lagrangian for the quadratic theory is separated into two Henneaux–Teitelboim Lagrangians. We also discuss the method of generating explicit nonlinear theories with p=1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$p=1$$\\end{document}. Finally, we also show that the M5-brane action in the Sen formulation is separated into a Henneaux–Teitelboim action in unphysical sector and a gauge-fixed PST in physical sector.

Holographic 12\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\frac{1}{2} $$\\end{document}-BPS surface defects in ABJM

We study the class of AdS3 × ℂℙ3 solutions to massive Type IIA supergravity with osp\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\mathfrak{osp} $$\\end{document}(6|2) superconformal algebra recently constructed in [1]. These solutions are foliations over an interval preserving N\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\mathcal{N} $$\\end{document} = (0, 6) supersymmetry in two dimensions, that in the massless limit can be mapped to the AdS4 × ℂℙ3 solution of ABJM/ABJ. We show that in the massive case extra NS5-D8 branes, that we interpret as 12\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\frac{1}{2} $$\\end{document}-BPS surface defect branes within the ABJ theory, backreact in the geometry and turn one of the 3d field theory directions onto an energy scale, generating a flow towards a 2d CFT. We construct explicit quiver field theories that we propose flow in the IR to the (0, 6) SCFTs dual to the solutions. Finally, we show that the AdS3 solutions realise geometrically, in terms of large gauge transformations, an extension to the massive case of Seiberg duality in ABJ theories proposed in the literature.

A generalized framework of two-way coupled numerical model for fluid-structure-seabed interaction (FSSI): Explicit algorithm

In a complex marine dynamics environment, the consideration of fluid-structure-seabed interaction (FSSI) plays a vital role in reliably analyzing the dynamic response of marine structures, and in assessing their structural dynamic stability. Currently, the predominant numerical analysis used worldwide for the problems of wave-seabed interaction and seawater-structure-seabed interaction is primarily the one-way coupling method. While only a few two-way coupled models are being developed. Consequently, two issues are brought up: (1) For the cases involving small deformation and displacement, the degree of discrepancy can't be quantitatively identified between the results obtained respectively from one-way coupling models and two-way coupled models which are more rigorous in mathematics and physics. (2) For the cases involving large deformation and displacement, one-way coupling models should be non-applicable. To address this problem, this study first proposes an explicit two-way coupling theory for the fluid-structure-seabed interaction. Then, a two-way coupled numerical model is developed by integrating the soil-structure dynamics software FssiCAS, and an OpenFOAM-based CFD solver OlaFlow by utilizing the data exchange library preCICE. This two-way coupled model has been embedded into the software FssiCAS. The reliability of the developed two-way coupled model is systematically validated through a rigorous verification process. Subsequently, a comparative study is conducted between the newly developed two-way coupled model and the existing one-way coupling model, to investigate the ocean wave-seabed interaction, as well as the interaction process between ocean wave, a breakwater, and seabed foundation. A comprehensive analysis is performed by comparing the differences in the wave profiles in fluid domain, dynamic displacement of structure and seabed foundation, seepage, pore pressure accumulation, and liquefaction in seabed foundation solved by the two-way and one-way coupled models. Finally, the suitability of the one-way and two-way coupled models in different applicable scenarios was discussed.

Soap bubbles and convex cones: optimal quantitative rigidity

We consider a class of recent rigidity results in a convex cone Σ ⊆ R N \Sigma \subseteq \mathbb {R}^N . These include overdetermined Serrin-type problems for a mixed boundary value problem relative to Σ \Sigma , Alexandrov’s soap bubble-type results relative to Σ \Sigma , and Heintze-Karcher’s inequality relative to Σ \Sigma . Each rigidity result is obtained here by means of a single integral identity and holds true under weak integral overdeterminations in possibly non-smooth cones. Optimal quantitative stability estimates are obtained in terms of an L 2 L^2 -pseudodistance. In particular, the optimal stability estimate for Heintze-Karcher’s inequality is new even in the classical case Σ = R N \Sigma = \mathbb {R}^N . Stability bounds in terms of the Hausdorff distance are also provided. Several new results are established and exploited, including a new Poincaré-type inequality for vector fields whose normal components vanish on a portion of the boundary and an explicit (possibly weighted) trace theory – relative to the cone Σ \Sigma – for harmonic functions satisfying a homogeneous Neumann condition on the portion of the boundary contained in ∂ Σ \partial \Sigma . We also introduce new notions of uniform interior and exterior sphere conditions relative to the cone Σ ⊆ R N \Sigma \subseteq \mathbb {R}^N , which allow to obtain (via barrier arguments) uniform lower and upper bounds for the gradient in the mixed boundary value-setting. In the particular case Σ = R N \Sigma =\mathbb {R}^N , these conditions return the classical uniform interior and exterior sphere conditions (together with the associated classical gradient bounds of the Dirichlet setting).

The origin and function of external representations

External representations ( ERs) are objects or performances in the world whose proper function is to communicate about other things in the world. Why and how did we make them, and what do they give us? We outline a simple framework for thinking about ERs grounded in modern machine learning. We propose a minimal set of neural mechanisms needed for open-ended ER production. Our constructivist enactive view contrasts with nativist views which propose specialist neural modules requiring symbolic internal representations. We propose a plausible set of (biological and cultural) evolutionary steps to full Gricean symbolic communication via a set of increasingly complex enactive algorithms for ER production. A pragmatic space of games is defined, which includes not only fully cooperative language games but also science, art, and evolved signal manipulation games. This space is defined by the complexity of learning needed by sender and receiver. We propose that one important step towards open-ended ER use was selection for bush reading, which like mind-reading is an inferential process requiring complex contextual and syntactic understanding of cues about events displaced in space and time. Bush reading pre-adapted receivers to be receptive, competent, and perspicacious interpreters of later intentionally produced signals about hidden topics such as felt mental states. This paved the way for minimally Gricean communication, which subsequently could be bootstrapped into explicit theories of mind, folk psychology narratives, and symbolic language in general. Recent findings in cognitive archaeology are integrated within the framework, and new experiments in machine learning suggested.

Brumer–Stark units and explicit class field theory

Brumer–Stark units and explicit class field theory

Developing theories of change to advance center for teaching and learning work

A theory of change is a prediction about desired outcomes and the actions that may prompt them. Research on educational change suggests that explicit theories of change are essential for effectively engaging in academic change work. While many centers for teaching and learning (CTL) express aims around organizational change, a recent study was not able to identify any theories of change made public in annual reports or websites. Therefore, we outline an adaptable process for other CTLs to discuss and make explicit their own theories of change. This process involves four steps, moving across scale of a CTL (large group, small group, and individual). We offer recommendations for other types of CTLs, such as “centers of one,” to develop a theory of change and theorize about current and potential utility of a theory of change for a CTL’s work.

A Novel Explicit Canonical Dynamic Modeling Method for Multi-Rigid-Body Mechanisms Considering Joint Friction

Friction is an inevitable phenomenon in mechanical systems that affects the dynamic characteristics of systems. To reduce the modeling complexity of complex multi-rigid-body mechanisms, a novel explicit canonical dynamic modeling method considering joint friction is proposed. Based on the explicit dynamic modeling theory that we have proposed, the solution of the constraint force required by the joint friction modeling of multi-rigid-body mechanisms is derived and improved, which greatly simplifies the solution of the constraint force. According to the obtained explicit expression of the constraint force equations, two joint friction models of the Coulomb–viscous effect and Stribeck effect are derived in analytical form. Moreover, the Stribeck effect of the joint is experimentally analyzed. A five-axis tree-chain mechanism and a three-loop closed-chain mechanism are chosen to demonstrate the method and compared with ADAMS software. Moreover, the proposed model is analyzed and compared with other methods.

Topic models indicate textual aboutness and pragmatics: Valuation practices in Islamophobic discourse

This study investigates the analysis of evaluative linguistic patterns within the context of the German-language Islamophobic online blog PI-News. The corpus consists of texts that refer to the Quran. The innovation of this research lies in two primary dimensions: Firstly, it adopts John Dewey’s pragmatism to establish an explicit valuation theory. Secondly, it extends the boundaries of topic modeling in the digital humanities by integrating van Dijk’s differentiation between aboutness and pragmatic macrostructures of texts. Notably, within these pragmatic macrostructures, the study highlights the practice of quoting Quran suras as a significant linguistic pattern. Together with the analysis of topic distribution and topic pathways in texts, the paper illustrates how evaluative practices reinforce the ideal of an Islam-free Europe.

Dual-process theories, cognitive architectures, and hybrid neural-symbolic models

This position paper discusses relationships among hybrid neural-symbolic models, dual-process theories, and cognitive architectures. It provides some historical backgrounds and argues that dual-process (implicit versus explicit) theories have significant implications for developing neural-symbolic (neurosymbolic) models. Furthermore, computational cognitive architectures can help to disentangle issues concerning dual-process theories and thus help the development of neural-symbolic models (in this way as well as in other ways).

Probing the Representational Structure of Regular Polysemy via Sense Analogy Questions: Insights from Contextual Word Vectors.

Regular polysemes are sets of ambiguous words that all share the same relationship between their meanings, such as CHICKEN and LOBSTER both referring to an animal or its meat. To probe how a distributional semantic model, here exemplified by bidirectional encoder representations from transformers (BERT), represents regular polysemy, we analyzed whether its embeddings support answering sense analogy questions similar to "is the mapping between CHICKEN (as an animal) and CHICKEN (as a meat) similar to that which maps between LOBSTER (as an animal) to LOBSTER (as a meat)?" We did so using the LRcos model, which combines a logistic regression classifier of different categories (e.g., animal vs. meat) with a measure of cosine similarity. We found that (a) the model was sensitive to the shared structure within a given regular relationship; (b) the shared structure varies across different regular relationships (e.g., animal/meat vs. location/organization), potentially reflective of a "regularity continuum;" (c) some high-order latent structure is shared across different regular relationships, suggestive of a similar latent structure across different types of relationships; and (d) there is a lack of evidence for the aforementioned effects being explained by meaning overlap. Lastly, we found that both components of the LRcos model made important contributions to accurate responding and that a variation of this method could yield an accuracy boost of 10% in answering sense analogy questions. These findings enrich previous theoretical work on regular polysemy with a computationally explicit theory and methods, and provide evidence for an important organizational principle for the mental lexicon and the broader conceptual knowledgesystem.

The planar limit of the N\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\mathcal{N} $$\\end{document} = 2 E-theory: numerical calculations and the large λ expansion

We study correlation functions of local operators and Wilson loop expectation values in the planar limit of a 4d N\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\mathcal{N} $$\\end{document} = 2 superconformal SU(N) YM theory with hypermultiplets in the symmetric and antisymmetric representations of the gauge group. This so called E theory is closely related to N\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\mathcal{N} $$\\end{document} = 4 SYM and has a holographic description in terms of a ℤ2 orientifold of AdS5 × S5. Using recent matrix model results based on supersymmetric localization we develop efficient numerical methods to calculate two- and three-point functions of certain single trace operators as well as 1/2-BPS Wilson loop expectation values as a function of the ’t Hooft coupling λ. We use our numerical results to arrive at simple analytic expressions for these correlators valid up to sixth order in the λ−1/2 strong coupling expansion. These results provide explicit field theory predictions for the α′ corrections to the supergravity approximation of type IIB string theory on the AdS5 × S5/ℤ2 orientifold.

Social media in accounting research: A review and future research agenda

In recent years, accounting scholars have shown growing interest in utilizing social media (SM) for research. Using a structured literature review of 86 articles, this study aims to reconcile insights from diverse literature to understand the current trends in SM accounting research and propose an agenda for future studies. Our findings reveal that SM accounting research is still at an early stage despite the increase of articles in recent years. In particular, we find that most studies focus on (publicly listed) corporate use of SM (mostly Twitter and Facebook) to disseminate financial and non-financial information in the North American and European regions. However, there is still a limited understanding of how SM interactions among various parties may push for greater transparency in different forms of organizations and in countries where stakeholder interests are less protected. While SM studies use system-oriented (such as institutional, legitimacy, and stakeholder theories) and economic-based theories, most studies only use SM as an empirical platform and rely on empirically developed arguments without reference to explicit theories. Finally, we identify common research themes and suggest promising avenues for future accounting research.

Process evaluation of a primary care-based type 2 diabetes remission project in the North East of England.

A type 2 diabetes remission project, Remission in Diabetes (REMI.D), funded by Sport England, was developed by stakeholders based in the North East of England and begun in early 2020. This local delivery pilot sought to tackle health inequalities by working with multiple organisations to demonstrate a way of scaling up an effective type 2 diabetes remission strategy which included both physical activity and dietary components. The intended delivery of the original project was impacted by the COVID-19 pandemic and changes were made to the project delivery in 2022. The aim of this process evaluation was to learn from the reactive decisions taken by stakeholders which altered the REMI.D project in response to the COVID-19 pandemic. Twelve stakeholders (from local authorities, secondary care, universities, NHS England commissioning, Diabetes UK, Sport England, Everyone Active and Active Partnerships) involved in the design and delivery of the intervention took part in a semi-structured interview lasting up to 60 min. Interviews were recorded and transcribed verbatim. Thematic analysis used the pre-determined 'core content' themes from the Medical Research Council and National Institute for Health Research framework for developing and evaluating complex interventions. Three topics for discussion emerged as follows: (a) lack of effective collaboration, (b) perception of change and (c) scalability of the intervention. Hierarchy within the stakeholder group initially hampered collaboration. Change was reactive as a result of the COVID-19 pandemic. Project changes reduced project sustainability and scalability but offered valuable learning about the need for explicit project theory for partnership working, co-production with service users and project flexibility for long-term health behaviour change.

Characterising the interventions designed to affect the reporting of musculoskeletal imaging: a scoping review protocol using the COM-B model

IntroductionAttributing musculoskeletal (MSK) pain to normal and commonly occurring imaging findings, such as tendon, cartilage and spinal disc degeneration, has been shown to increase people’s fear of movement, reduce their...

Peer support interventions in maternal and child healthcare delivery in sub-Saharan Africa: protocol for a realist review

BackgroundPeer support has been proposed as a promising policy intervention for addressing adverse maternal and child healthcare (MCH) outcomes in sub-Saharan Africa (SSA). Existing reviews on peer support largely draw on evidence from high-income countries or focus on single services like breastfeeding, nutrition or postnatal care. In contrast, this review aims to provide a comprehensive overview of the empirical literature on peer support interventions across various MCH services in sub-Saharan Africa. Specifically, we aim to understand how, why, for whom, and in what circumstances different forms of MCH peer support interventions contribute to improving healthcare outcomes in sub-Saharan Africa.MethodsThis review follows five iterative steps for undertaking realist reviews (1) defining the review scope; (2) developing initial programme theories; (3) searching for evidence; (4) selecting and appraising evidence; and (5) extracting, analysing and synthesising evidence. Four databases–Cochrane Library, PubMed, CINAHL, and EMBASE–were repeatedly searched between March and June 2021. From a large volume of records retrieved from the database and citation search, 61 papers have been selected for review. We will conduct a second search of the same database covering June 2021 to the present before the final extraction and synthesis. The final list of selected papers will be imported into NVivo 12 software and organised, extracted, analysed and synthesised iteratively to examine and illustrate the causal links between contexts, mechanisms and outcomes of MCH peer support interventions in SSA. We have drawn on the existing literature on peer support in healthcare generally to develop initial programme theories. We will then use the empirical literature on MCH peer support interventions in SSA, inputs from a stakeholders’ workshop in Ghana and a conference presentation to refine the initial programme theory.DiscussionThe review will develop an explicit theory of peer support intervention in healthcare delivery and provide insights for developing evidence-informed policy on the intervention. Drawing lessons from the different national contexts and diverse areas of MCH in SSA, the review will provide an analytically generalizable programme theory that can guide intervention design and implementation. While focusing on MCH peer support interventions in SSA, the review contributes to evolving conversations on the use of theory for health policy planning and complex intervention design and implementation globally.Trial registrationPROSPERO registration ID: CRD42023427751.

Utility-based predictions of military escalation: Why experts forecasted Russia would not invade Ukraine

ABSTRACT When Russia amassed troops in the winter of 2021–2022, many analysts deemed a large-scale invasion of Ukraine unlikely. Surveying the expert literature, we establish that these arguments largely relied on utility-based reasoning: Analysts thought an invasion was improbable, as it would foreseeably entail massive costs for Russia, its people, and its regime. We show that this regnant expert opinion had not sufficiently accounted for the Russian regime’s tendencies to increasingly accept risks, coupled with an inadequate processing of information on Ukrainian and Western views and policies. We argue that analysts miscalculated partially because the most prominent facts, long-term trends, and causal mechanisms available to them jointly suggested Russian cost-sensitivity, but provided only weak signs of countervailing factors. We thereby showcase that good forecasting requires explicit theory with a view on multiple interacting causal factors, area expertise and Socratic humility on the extent, context and certainty of our findings.