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Investigation and implementation of Active Willis Metamaterials (AWM) have been done exclusively, in all the available literature, by approaches that do not rely on any solid control theory basis. When coupled with piezoelectric control elements, the available approaches have not included, from the first principles, the exact form of the constitutive relationship of the piezoelectric materials. Furthermore, in all these approaches, stability analysis, robustness, ability to accommodate uncertainty or parameter changes, or consideration of disturbance rejection has not been addressed at all. More importantly, the available formulations have always mixed the flow and effort variables of the AWM, resulting in a form that is totally incompatible for the use in generating, investigating, or even designing any appropriate sensing or control applications of the material. In this paper, the piezoelectric-based AWM is modeled, from the first principles, to develop a constitutive coupling form that enables its use in actuation, sensing, and as an integrated controller that can be analyzed, designed, and optimized using the classical, optimal, and robust control system theories. Lagrange dynamics formulation is used to generate the equations governing the Willis coupling, the piezoelectric coupling, as well as the active robust controller. With this developed controlled-based structure of the AWM, the inherent and powerful capabilities of the AWM that lie in its ability to robustly control the material properties themselves such as the compliance (or stiffness) and specific volume (or density) are demonstrated in great detail via several numerical examples. Controlling these properties enables the AWM to be used in numerous important and imaginative applications such as cloaking, beam shifting, beam focusing, as well as many other applications that are limited only by our imagination. [ABSTRACT FROM AUTHOR]

We report high-level calculations of the excited states of [2,2]-paracyclophane (PCP), which was recently investigated experimentally by ultrafast pump–probe experiments on oriented single crystals [Haggag et al., ChemPhotoChem 6 e202200181 (2022)]. PCP, in which the orientation of the two benzene rings and their range of motion are constrained, serves as a model for studying benzene excimer formation. The character of the excimer state and the state responsible for the brightest transition are similar to those of the benzene dimer. The constrained structure of PCP allows one to focus on the most important degree of freedom, the inter-ring distance. The calculations explain the main features of the transient absorption spectral evolution. This brightest transition of the excimer is polarized along the inter-fragment axis. The absorption of the light polarized in the plane of the rings reveals the presence of other absorbing states of Rydberg character, with much weaker intensities. We also report new transient absorption data obtained by a broadband 8 fs pump, which time-resolve strong modulations of the excimer absorption. The combination of theory and experiment provides a detailed picture of the evolution of the electronic structure of the PCP excimer in the course of a single molecular vibration. [ABSTRACT FROM AUTHOR]

Supply chain decarbonisation has become a strategic requirement in the era of a net-zero economy. Despite the significant role of Big Data Analytics (BDA) in decarbonising the supply chain (SC), no prior study has evaluated it systematically. The present study aims to provide a systematic literature review on the applications and outcomes of big data analytics in SC decarbonisation. A total of 69 papers on applying BDA technology for supply chain decarbonisation published between 2016 and 2021 have been selected following the PRISMA protocol. The findings show that the topic is evolving. Studies employed methods such as surveys (30), case studies (11), and conceptual research designs (8). Thematic analysis reveals that 65% of the studies are grounded in resource-advantage theories, organisational theories, and system theories. Studies from India and China (35%) dominate the topic, while most studies have been conducted on the food and manufacturing industries. Further, this study applied the Antecedent-Decision-Outcomes (ADO) framework in BDA-based SC decarbonisation. Antecedents include BDA resources and capabilities, workforce skills, and supplier capabilities. Decisions refer to improving decision-making across the supply chain. Outcomes refer to improving decarbonisation, sustainable growth, and sustainable innovativeness. Future research directions and questions are provided using the Theory-Context-Methodology (TCM) framework. [ABSTRACT FROM AUTHOR]

Employees play a central role in organizational functioning and representation. HR managers thus strive to create an attractive employer image that stimulates employees' attachment and ambassadorship. However, presently, there is limited research about how employees perceive and react toward their organization's employer brand. More importantly, the studies available have focused on content attributes only (i.e., instrumental and symbolic image dimensions). This has resulted in limited (content‐based) understanding of the construct and failure to incorporate its branding‐related aspects (process attributes) which represent the crux of employer branding theory. Thus, using the HRM system strength theory and employer branding literature, this article examines three process characteristics (i.e., employer brand distinctiveness, consistency, and consensus) vis‐à‐vis instrumental and symbolic content attributes to understand employee reactions (i.e., employer attractiveness, organizational identification, and employee ambassadorship). Data were collected at two times through Prolific Academic with 254 UK and US employees. Results suggest that employer brand process attributes are valuable sources to enhance employees' identification with their organization. Moreover, distinctiveness and consistency seem especially instrumental in enhancing employees' attractiveness perceptions and display of positive ambassadorship. In addition, the process attributes explain significant incremental and unique variance beyond content attributes in employee reactions. [ABSTRACT FROM AUTHOR]

Instanton-based rate theory is a powerful tool that is used to explore tunneling in many-dimensional systems. Yet, it diverges at the so-called "crossover temperature." Using the uniform semiclassical transmission probability of Kemble [Phys. Rev. 48, 549 (1935)], we showed recently that in one dimension, one might derive a uniform semiclassical instanton rate theory, which has no divergence. In this paper, we generalize this uniform theory to many-dimensional systems. The resulting theory uses the same input as in the previous instanton theory, yet does not suffer from the divergence. The application of the uniform theory to dissipative systems is considered and used to revise Wolynes' well-known analytical expression for the rate [P. G. Wolynes, Phys. Rev. Lett. 47, 968 (1981)] so that it does not diverge at the "crossover temperature." [ABSTRACT FROM AUTHOR]

International collaborations are important for developing science systems. Using a dataset of South African university scientists, we ask whether social capital relevant to international collaboration held by one scientist spills over to local colleagues. Distinguishing between different ways of acquiring foreign ties, we find that 20% of our cases resemble the most-studied form of international collaborations, via the unique ties of an individual with specific characteristics, e.g., foreign research training. In all other cases, both personal and local peers' international social capital is relevant for foreign tie formation. Underlining the systemic functioning of science, international social capital is activated through scientific collaboration among local scientists. The mediating effect of local scientific collaboration is present across all scientific fields and holds for scientists trained locally or abroad. Our findings thus imply that local collaboration is a relevant mechanism to strengthen international collaboration and the formation of international social capital. [ABSTRACT FROM AUTHOR]

A multi-tier supply chain is a complex system as it covers a focal company and multiple tiers of suppliers in a complex supply chain network. This study explores the complexity in multi-tier sustainable supply chain management (SSCM) through a social systems theory perspective. We carried out a case study on IKEA China's sustainable cotton initiative and examined its five cotton-textile supply chains. The primary data were collected through 22 semi-structured interviews with managers of IKEA China and their multi-tier suppliers. The findings suggest that in order to cope with environmental complexity in implementing multi-tier sustainable initiatives, focal companies tend to create both internal complexity and collaborative complexity in a variety of governance mechanisms. In addition, environmental overlap and available collaborative complexity increase in this process and can feed back into systems to facilitate further creation of requisite variety. We contribute to the multi-tier SSCM literature through providing an in-depth understanding of nuanced mechanisms of managing different tiers of suppliers to cope with complexities by adopting a social systems theory perspective. We also contribute to multi-tier supply chain governance mechanisms from an evolution perspective. [ABSTRACT FROM AUTHOR]

In spring 2020, schools across the world closed down due to the COVID-19 pandemic. Since then, there have been numerous inquiries into how the school closures affected students. However, most of these inquiries apply a simple causal perspective according to which school closures are described as cause, and poor wellbeing and learning loss as effects. The aim of this article is to identify the complex social mechanisms that were triggered in the schoolchildren’s everyday lives in relation to school and home, thus identifying a significant missing link between cause and effect. The method employed is to analyze quantitative and qualitative data concerning students’ (n = 5,953) and parents’ (n = 5,054) reactions to the school closures in Denmark through the lens of a system theoretical understanding of inclusion and exclusion mechanisms. The analysis demonstrates that one important reason for the consequences of school closures was that fundamental school-based inclusion and exclusion processes were interrupted, and that these processes could not be fully compensated by parents and siblings or by the use of digital media. Finally, the analysis argues that the closures not only affected the students’ learning and wellbeing but also presented a threat to their acquisition of fundamental inclusion and exclusion competencies. [ABSTRACT FROM AUTHOR]

The sums S N ω , ζ = ∑ n - 0 N - 1 1 n 1 + e - 2 π i ω n + ω 2 + ζ , where ω and ζ are parameters, are related to trigonometric products from the theory of quasi-periodic operators as well as to a special function kindred to the Malyuzhinets function from the diffraction theory, the hyperbolic Ruijsenaars G-function, which arose in connection with the theory of integrable systems, and the Faddeev quantum dilogarithm, which plays an important role in the knot theory, Teichmuller quantum theory and the complex Chern–Simons theory. Assuming that ω ∈ (0, 1) and ζ ∈ ℂ−, we describe the behavior of logarithmic sums for large N using renormalization formulas similar to those well-known in the theory of Gaussian exponential sums. [ABSTRACT FROM AUTHOR]

The BC-method is the approach to inverse problems based on their connection with control theory and theory of systems. The main fragment of its numerical implementation is the matrix inversion of the so-called connecting operator. In multidimensional problems, its matrix is ill-conditioned and large in size, which yields the rapid growth of the volume of computations. The paper reveals block-Toeplitz structure of this matrix, using which one can significantly reduce the amount of computations. [ABSTRACT FROM AUTHOR]

Background: Current local food environments encourage poor diets, posing a significant threat to public and planetary health. Acknowledging and addressing its inherent complexity is vital to making meaningful improvements to the food environment. Using a participatory approach with local stakeholders, this study aims to gain insight into the factors and mechanisms underlying the local food environment and to identify leverage points and system-based actions to foster healthy and sustainable local food environments. Methods: A systems-thinking approach was used in a Dutch municipality in 2022. Two group model building (GMB) workshops were held with community stakeholders (e.g. local policymakers, retailers and residents). During the first workshop (June 2022), factors and mechanisms influencing the local food environment were identified and visualized through a causal loop diagram (CLD). During the second workshop, leverage points and system-based actions to improve food environments were identified by the stakeholders. Four months after (October 2022), an action-implementation meeting was organized to stimulate the implementation of selected actions. Progress was monitored through brief telephone interviews 6 and 12 months after the second workshop. Results: The CLD visualises the factors and mechanisms influencing the local food environment from the point of view of the community stakeholders. The CLD consists of 46 factors shaping the local food environment, which were categorized into four identified subsystems: societal factors, individual, socio-economic factors, commercial factors and political factors. Eight leverage points were identified within the CLD, for example, 'lobby from food industry', 'governmental food policies' and 'e-commerce and platform economy'. Stakeholders formulated 20 actions targeting the identified leverage points. During the action-implementation meeting, long-term plans were created for five actions. After 1 year, only one participant (policy advisory role) remained actively engaged in three of these actions. Conclusions: This study yields insight into the numerous factors and mechanisms underlying the local food environment and identified system-based actions as perceived by local stakeholders to improve this food environment locally. The CLD offers stakeholders valuable insights on employing a systems approach when enhancing food environments. More research is necessary, especially into the long-term processes and effects of implementing system-oriented actions to improve local food environments. [ABSTRACT FROM AUTHOR]

There is growing support and interest in postsecondary interdisciplinary environmental education, which integrates concepts and disciplines in addition to providing varied perspectives. There is a need to assess student learning in these programs as well as rigorous evaluation of educational practices, especially of complex synthesis concepts. This work tests a text classification machine learning model as a tool to assess student systems thinking capabilities using two questions anchored by the Food-Energy-Water (FEW) Nexus phenomena by answering two questions (1) Can machine learning models be used to identify instructor-determined important concepts in student responses? (2) What do college students know about the interconnections between food, energy, and water, and how have students assimilated systems thinking into their constructed responses about FEW? Reported here is a broad range of model performances across 26 text classification models associated with two different assessment items, with model accuracy ranging from 0.755 to 0.992. Expert-like responses were infrequent in our dataset compared to responses providing simpler, incomplete explanations of the systems presented in the question. For those students moving from describing individual effects to multiple effects, their reasoning about the mechanism behind the system indicates advanced systems thinking ability. Specifically, students exhibit higher expertise in explaining changing water usage than discussing trade-offs for such changing usage. This research represents one of the first attempts to assess the links between foundational, discipline-specific concepts and systems thinking ability. These text classification approaches to scoring student FEW Nexus Constructed Responses (CR) indicate how these approaches can be used, in addition to several future research priorities for interdisciplinary, practice-based education research. Development of further complex question items using machine learning would allow evaluation of the relationship between foundational concept understanding and integration of those concepts as well as a more nuanced understanding of student comprehension of complex interdisciplinary concepts. [ABSTRACT FROM AUTHOR]

While intellectual property (IP) management is critical for innovation, specific knowledge and innovation patterns within it can obstruct commercialisation. This study explores how these patterns impede the path to market success for emerging innovations. We introduce a novel method to detect and recognise these patterns, offering insights into factors contributing to innovation system failure. Applying the Triple Helix Model, we leverage text mining, network analysis, and structural equation modelling within the Russian pharmaceutical industry. Our research reveals limitations in the triple helix model’s ability to capture problematic innovation patterns. Notably, local-closed and local semi-closed innovation networks emerge as significant barriers to commercialisation, further exacerbated by foreign dominance. While strong actor synergy is crucial, it alone cannot guarantee competitive advantage. Factors like geographical distance, disciplinary silos, and limited external collaboration further hinder success. This study highlights the need for effective knowledge production and collaboration practices, alongside strong synergy, to achieve market-leading innovations. Recognising and addressing these patterns can inform policy decisions, ultimately fostering more robust innovation outcomes, advancing innovation system theory in the process. [ABSTRACT FROM AUTHOR]

As digitally enabled information systems play an increasingly central role in culture and economics, their negative consequences have become apparent. This guest editorial addresses the urgent need for information scientists to take a more deliberate stance in designing and guiding the evolution of these systems. We propose a framework for conceptualizing “healthier information ecosystems” by drawing on theories from complex systems and ecological research, grounded in a value‐oriented approach. The article reviews key concepts from systems science, complex systems, and ecology, with a focus on ecosystem and adaptation research. These perspectives offer analytical approaches for decomposing information ecosystems and provide a foundation for understanding “health” in the context of evolving, open systems. Unlike natural ecosystems, information ecosystems must be evaluated according to human values; thus, we articulate a set of values as a starting point for defining health in this context. By introducing insights from beyond the field of information systems, we aim to instigate scholarly dialog, connect prior work in new ways, and reveal new opportunities for research and intervention. This connective and argumentative contribution is intended to guide future research and identify solutions to the proliferating problems in our current information ecosystems. [ABSTRACT FROM AUTHOR]

Machine learning influences numerous aspects of modern society, empowers new technologies, from Alphago to ChatGPT, and increasingly materializes in consumer products such as smartphones and self-driving cars. Despite the vital role and broad applications of artificial neural networks, we lack systematic approaches, such as network science, to understand their underlying mechanism. The difficulty is rooted in many possible model configurations, each with different hyper-parameters and weighted architectures determined by noisy data. We bridge the gap by developing a mathematical framework that maps the neural network's performance to the network characters of the line graph governed by the edge dynamics of stochastic gradient descent differential equations. This framework enables us to derive a neural capacitance metric to universally capture a model's generalization capability on a downstream task and predict model performance using only early training results. The numerical results on 17 pre-trained ImageNet models across five benchmark datasets and one NAS benchmark indicate that our neural capacitance metric is a powerful indicator for model selection based only on early training results and is more efficient than state-of-the-art methods. Understanding of artificial neural networks function, and their ability to effectively solve specific tasks, still require more rigorous analytical background. Using network science and dynamical systems tools, the authors develop a framework for predicting the performance of artificial neural networks [ABSTRACT FROM AUTHOR]

Background: Primary care is often described as slow to change. But conceptualized through complexity theory, primary care is continually changing in unpredictable, non-linear ways through self-organization processes. Self-organization has proven hard to study directly. We aimed to develop a methodology to study self-organization and describe how a primary care clinic self-organizes over time. Methodology: We completed a virtual case study of an urban primary care clinic from May-Nov 2021, applying methodological insights from actor-network theory to examine the complexity theory concept of self-organization. We chose to focus our attention on self-organization activities that alter organizational routines. Data included fieldnotes of observed team meetings, document collection, interviews with clinic members, and notes from brief weekly discussions to detect actions to change clinical and administrative routines. Adapting schema analysis, we described changes to different organizational routines chronologically, then explored intersecting changes. We sought feedback on results from the participating clinic. Findings: Re-establishing equilibrium remained challenging well into the COVID-19 pandemic. The primary care clinic continued to self-organize in response to changing health policies, unintended consequences of earlier adaptations, staff changes, and clinical care initiatives. Physical space, technologies, external and internal policies, guidelines, and clinic members all influenced self-organization. Changing one created ripple effects, sometimes generating new, unanticipated problems. Member checking confirmed we captured most of the changes to organizational routines during the case study period. Conclusions: Through insights from actor-network theory, applied to studying actions taken that alter organizational routines, it is possible to operationalize the theoretical construct of self-organization. Our methodology illuminates the primary care clinic as a continually changing entity with co-existing and intersecting processes of self-organization in response to varied change pressures. [ABSTRACT FROM AUTHOR]

In this work, we study the invasion dynamics of a stage-structured population located in a one-dimensional periodic lattice. With a biologically relevant hypothesis that the population diffuses in its immature stage, we derive a novel spatially heterogeneous population model with coupled local and nonlocal effects. Assuming a KPP-type structure, we obtain the existence and variational characterization of spreading speed by appealing to monotone dynamical system theories. Further, we study the dependence of the spreading speed on the dispersal rate of immature population; it turns out that there exists an optimal dispersal strategy to maximize the speed. Numerical simulations further suggest that such an optimal strategy is unique. [ABSTRACT FROM AUTHOR]

Diplomacy is often presented as subordinated to politics as if it merely received politically willed 'inputs' to produce politically structured 'outputs'. However, diplomacy often deviates from political instructions. It can even operate almost without any political considerations whatsoever. This observation gives rise to a sense that politics and diplomacy operate as two separate systems that are mutually dependent and yet simultaneously independent from each other. To illuminate this relationship, the present paper draws from Modern Systems Theory (especially Parsons and Luhmann) to argue that politics and diplomacy engage in double interchanges: (1) they stimulate each other through premises for actions like 'foreign policy goals', and (2) they implement each other such that diplomatic happenings can be booked as political successes and vice versa. The discussion section outlines how the autonomy of the two systems varies empirically – such as in the case of politically appointed diplomats – and how extreme cases of autonomous operations (apolitical diplomacy or adiplomatic politics) face negative sanctions. [ABSTRACT FROM AUTHOR]

The four-dimensional ellipsoid of an anisotropic hyper-structure corresponds to the four-dimensional sphere of an isotropic hyper-structure. In three dimensions, both theories for spherical and ellipsoidal harmonics have been developed by Laplace and Lamé, respectively. Nevertheless, in four dimensions, only the theory of hyper-spherical harmonics is hitherto known. This void in the literature is expected to be filled up by the present work. In fact, it is well known that the spectral decomposition of the Laplace equation in three-dimensional ellipsoidal geometry leads to the Lamé equation. This Lamé equation governs each one of the spectral functions corresponding to the three ellipsoidal coordinates, which, however, live in non-overlapping intervals. The analysis of the Lamé equation leads to four classes of Lamé functions, giving a total of 2n + 1 functions of degree n. In four dimensions, a much more elaborate procedure leads to similar results for the hyper-ellipsoidal structure. Actually, we demonstrate here that there are eight classes of the spectral hyper-Lamé equation and we provide a complete analysis for each one of them. The number of hyper-Lamé functions of degree n is (n + 1)2; that is, n2 more functions than the three-dimensional case. However, the main difficulty in the four-dimensional analysis concerns the evaluation of the three separation constants appearing during the separation process. One of them can be extracted from the corresponding theory of the hyper-sphero-conal system, but the other two constants are obtained via a much more complicated procedure than the three-dimensional case. In fact, the solution process exhibits specific nonlinearities of polynomial type, itemized for every class and every degree. An example of this procedure is demonstrated in detail in order to make the process clear. Finally, the hyper-ellipsoidal harmonics are given as the product of four identical hyper-Lamé functions, each one defined in its own domain, which are explicitly calculated and tabulated for every degree less than five. [ABSTRACT FROM AUTHOR]

We study multiple orthogonal polynomials exploiting their explicit determinantal representation in terms of moments. Our reasoning follows that applied to solve the Hermite–Padé approximation and interpolation problems. We also study families of multiple orthogonal polynomials obtained by variation of the measures known from the theory of discrete‐time Toda lattice equations. We present determinantal proofs of certain fundamental results of the theory, obtained earlier by other authors in a different setting. We also derive quadratic identities satisfied by the polynomials, which are new elements of the theory. Resulting equations allow to present multiple orthogonal polynomials within the theory of integrable systems. [ABSTRACT FROM AUTHOR]

Public administration is the largest part of the democratic state and a key consideration in understanding its legitimacy. Despite this, democratic theory is notoriously quiet about public administration. One exception is deliberative systems theories, which have recognized the importance of public administration and attempted to incorporate it within their orbit. This article examines how deliberative systems approaches have represented (a) the actors and institutions of public administration, (b) its mode of coordination, (c) its key legitimacy functions, (d) its legitimacy relationships, and (e) the possibilities for deliberative intervention. It argues that constructing public administration through the pre-existing conceptual categories of deliberative democracy, largely developed to explain the legitimacy of law-making, has led to some significant omissions and misunderstandings. The article redresses these issues by providing an expanded conceptualization of public administration, connected to the core concerns of deliberative and other democratic theories with democratic legitimacy and democratic reform. [ABSTRACT FROM AUTHOR]

Formation control is a fundamental task in the realm of autonomous multiagent systems. To drive a group of agents to maneuver continuously with the desired formation, this paper studies the finite‐time affine formation control problem with disturbances, input constraints and safety guarantee. A non‐singular terminal sliding mode control (NTSMC) is implemented to achieve finite‐time convergence of all followers to their desired positions. Additionally, an auxiliary system is deployed to address input constraints resulting from the physical properties of the affine formation system. To mitigate the impact of lumped disturbances, a finite‐time disturbance observer (FTDO) is employed to estimate the disturbances and compensate for their effects. Based on FTDO, the auxiliary system and the above NTSMC, a finite‐time robust controller is developed as the nominal controller. By modifying the nominal controllers to comply with safety constraints, control barrier functions are employed to ensure the safety of the formation system in obstacle‐filled environment. Finally, the effectiveness and feasibility of this method are validated through simulations and real‐world experiments. [ABSTRACT FROM AUTHOR]

Informed by ecological and Black feminist approaches, this inductive, thematic analysis analyzed narratives from 24 Black college women, ages 18–25, about the sexual socialization they received from multiple agents within and outside of the family. The themes were: Avoidance, Safety and Consent, Fun and Action-Centered Acts, (Mis)Information About Sexual Health, Gendered Norms, and Purity versus Sexual Freedom. The women received messages of avoidance, purity, safety, consent, and gendered norms, from their families and schools. Peers and media socialized women to view sex as fun and action centered. Given the persistent increases in sexually transmitted infections and diseases, and formation of longer-lasting romantic relationships during the college years, it is important for young adult women, including Black women, to receive adequate knowledge and skills to advocate for safe and healthy romantic sexual relationships. Implications of the findings are discussed. [ABSTRACT FROM AUTHOR]

We consider a class of forced continuous-time Lur'e systems obtained by applying nonlinear feedback to a higher-order linear differential equation which defines an input-output system in the sense of behavioural systems theory. This linear system directly relates the input and output signals and does not involve any internal, latent or state variables. A stability theory subsuming results of circle criterion type is developed, including criteria for input-to-output stability and strong integral input-to-output stability, concepts which are very much reminiscent of input-to-state stability and strong integral input-to-state stability, respectively. The methods used in the paper combine ideas from the behavioural approach to systems and control, absolute stability theory and input-to-state stability theory. [ABSTRACT FROM AUTHOR]

Critical systems heuristics (CSH) has been influential in the development of critical systems thinking. However, it is a relatively underutilised method compared with soft systems approaches such as soft systems methodology (SSM) and cognitive mapping. This may be in part due to the complexity of ideas underpinning CSH. Core ideas with which users must feel confident include boundary critique, coercion, emancipation, and "is" vs "ought to be" framings. These ideas were the subject of the early discourse surrounding CSH, which considered the role of boundary critique in systems research, the extent to which CSH could meaningfully address coercion, and the claims of CSH as an emancipatory approach. The purpose of this review is to provide clarity on these key concepts by reflecting on how they have been addressed in the CSH literature to date. We find that CSH has been applied in a range of problem contexts and is most frequently applied to address coercion or power asymmetries. CSH research is frequently associated with advocacy for marginalised groups, and we believe this is a natural extension of the methodological emancipation to which CSH aspires. In providing an overview of the key ideas underpinning CSH, we hope to lower the barrier to application for systems researchers and practitioners. [ABSTRACT FROM AUTHOR]

In past couple of years, management scholars have developed significant literature on the impact of Covid pandemic across various business and organizations formats. Although, the extant literature studied various aspects of SMEs, but they did not explore the pandemic impact to SMEs from the lenses of the systems approach. We examined how SMEs navigated through the Covid pandemic from the systems theory. We engaged narrative inquiry method and captured narrations from CEOs/board members of thirty SMEs in India. The grounded theory approach was adopted to analyse the data. The study found that SMEs' navigation through the pandemic was a complex and dynamic system encompassing input factors, immediate output, systemic output, navigating strategy, and policy environment. At the end, the study developed system-theoretic ecosystem framework of Covid impact on SMEs. [ABSTRACT FROM AUTHOR]

The goal of this study is to construct a novel iterative method to compute the matrix sign function using a different approach. It is discussed that the new method is globally convergent and asymptotically stable. It achieves the sixth order of convergence and only requires five matrix–matrix multiplications. The obtained results are extended to compute the number of eigenvalues of a matrix in a specified region of the complex plane. This is done by performing appropriate sequence of matrix sign computations. An application of this technique has been discussed in stability analysis of linear time‐invariant dynamic systems in control theory. Numerical results have been given to justify the effectual performance and superiority of the proposed method. Matrices of various sizes have been considered for this purpose. [ABSTRACT FROM AUTHOR]

The purpose of this research is to address the problem of synchronization between two identical biological hyperchaotic snap oscillator systems with unknown parameters at a fixed time, as well as to design a new theory for synchronizing two different chaotic systems. Firstly, we designed an adaptive controller using Lyapunov stability and fixed-time stability theory to achieve synchronization between two identical biological hyperchaotic snap oscillator in fixed time under unknown parameters. Among the results obtained, we found that the synchronization time for system states occurred in a very short time compared to results in previous research. Secondly, we extended and generalized synchronization between non-identical chaotic systems by creating a theory for achieving synchronization in which adaptive control and fixed-time stability are combined. Through the new theory, the unknown parameters in chaotic systems were estimated, and the settling time was determined, which turned out to be very short and independent of the initial conditions of the system states. One of what makes the scheme important is that it can be easily applied to most chaotic and even hyperchaotic systems in the shortest possible time. Finally, we gave examples of different systems to test the feasibility and effectiveness of the scheme that was designed. [ABSTRACT FROM AUTHOR]

This article revisits saturated stabilization of the feed‐forward systems that are subject to lower‐order perturbations, with the purpose of providing new analysis approaches. To carry out the saturation reduction analysis, we do not use the existing time‐interval based contradiction approach, but propose a Lyapunov function method; to deal with the reduced system (the closed‐loop system that does not contain saturation any longer), we do not use the "adding a power integrator" backstepping scheme, but propose an approach which is established by jointly using the vector Lyapunov function theory, a matrix measure stability theory and the switching systems theory. As a result, a quite number of inequality computations can be avoided, and the stability conditions summarized in two analysis procedures can be expressed by directly using the system parameters. This article also shows that the established approaches are applicable to the uncertain feedforward systems subject to linear input perturbation and consequently, allows to present new stabilizing control laws for several intractable under‐actuated systems. [ABSTRACT FROM AUTHOR]

For the position synchronization control problem of multiple nonlinear manipulator systems, a bounded distributed cooperative controller is designed in this paper. Based on a fixed‐time position observer, a distributed finite‐time synchronization controller is designed by using the saturated control technique and homogenous system theory. Compared with the existing results, the proposed distributed cooperative control algorithm not only guarantees finite‐time convergence but also satisfies the input saturation. Finally, some numerical simulation results are presented to verify the feasibility of the theory results with six‐degree‐of‐freedom robots. [ABSTRACT FROM AUTHOR]

This paper is concerned with the secure output consensus problem for the heterogeneous multi-agent systems under the event-triggered scheme in the presence of the denial-of-service attack. Without detecting the attack, the hold-input controller update strategy is adopted when some transmission data may be lost due to the effect of the attack. Based on the tolerable duration of the attack, a novel edge-based event-triggered scheme is developed. The scheme can avoid continuous communication and exclude Zeno behavior. With the aid of the switched system theory, output consensus is preserved. An example shows the effectiveness. • Secure problem for the heterogeneous multi-agent systems is solved in the presence of the denial-of-service attack. • A novel edge-based event-triggered scheme is developed based on the tolerable duration of the attack. • Without detecting the attack, the hold-input controller update strategy is adopted. • Output consensus is preserved with the aid of the switched system theory. [ABSTRACT FROM AUTHOR]

Many Australian students fail to meet an acceptable standard of reading proficiency. This can negatively impact their academic progress, social, and emotional well-being, and increase their risk of developing challenging behaviors. These risks and challenges have been found to compound over the lifetime of the learner. Unfortunately, the proportion of Australian students who fail to meet reading proficiency standards increases as they move through their years of schooling, and reading difficulties disproportionately affect historically marginalized groups. This has raised concerns about the effectiveness of instructional approaches used within the Australian education system, particularly in reading, and prompted discussions of reform. The purpose of this review paper was to examine the contributions of the science of reading and science of behavior to our collective knowledge regarding reading development and effective reading instruction, and how this knowledge is currently being used in the Australian context. We provide a discussion on the current state of reading instruction and achievement in Australia by considering national trends, inequities, and systemic challenges. Implications and recommendations to address inequities in reading outcomes, using both the science of reading and science of behavior, are discussed. [ABSTRACT FROM AUTHOR]

This paper intends to use UAM Corpus Tool 6.2 corpus annotation software to conduct a comparative ecological discourse analysis of the selections of the ecological literary work Walden - The Ponds and The Pond in Winter from the perspective of the attitude system of appraisal theory, aiming to reveal Thoreau’s attitude towards ecological environment and to prove the practicality of appraisal theory in the ecological discourse analysis of the literary work, and at the same time, to broaden the research for the ecological discourse analysis. It was found that the number of appreciative resources in The Ponds (412) was much greater than the number of judgement (61) and affect (39) resources and that the number of positive eco-discourses (270) and neutral/ambiguous eco-discourses (179) was also much greater than the number of negative discourses (63). The number of appraisal resources (185) in The Pond in Winter is much larger than that of judgement resources (50) and emotion resources (35), and the number of positive ecological discourses (270) and neutral/ambiguous ecological discourses (179) is much larger than that of negative ecological discourses (63), and positive ecological discourse (172) is much larger than neutral/ambiguous ecological discourse (65) and negative discourse (33). This reflects Thoreau’s ecological orientation of loving nature, respecting nature, opposing excessive destruction of nature by human beings, and advocating calling on human beings to protect nature. [ABSTRACT FROM AUTHOR]

Palliative care is dedicated to terminally ill patients with advanced disease, regardless of diagnosis, under the overarching premise of optimizing quality of life. This narrative review examines the extent to which principles of cybernetics and psychophysiology underlie this approach. Psychophysiology researches the physiological equivalents of psychological states and traits such as activation and individual reactivity, the interoception and the personal characteristics. Cybernetics specifies these principles, which are possible by understanding terms such as "psychophysiology" or "cybernetics" or "self-organization/autopoiesis". The meaning of these terms for palliative care can also be elucidated in relation to the terms "biofeedback", "consciousness", "pain", and "anxiety". The common themes of cybernetics and psychophysiology are environment, subjectivity, personality characteristics, the difference between time scale separation in cybernetic systems, and real-time procedures in environment and rhythm. These lead to special therapies based on psychophysiology, such as consciousness training. The concepts of quality of life, causality, the biopsychosocial model, therapy, and autonomy are examined as palliative care concepts. The equivalents can be described from the perspective of cybernetics. For some palliative care-related terms, cybernetic thinking is already present (quality of life, autonomy, symptom control), while for others, it is not (biopsychosocial). Cybernetic terms (complexity, stability, identity, rhythm) are still used to a lesser extent in palliative care. Terms like genetic basis are common in cybernetics and psychophysiology to explain the identity of the subject in transition. Identity, on the other hand, is the basis of the concept of dignity in palliative care. Psychophysiology investigates disturbances like pain and psychological illnesses, which are also present in palliative care. Psychophysiology, cybernetics, and palliative care have subjectivity and resources in common. Therapies based on cybernetic principles of psychophysiology can also be used for symptom control in palliative care in the oncology setting. [ABSTRACT FROM AUTHOR]

The tourism country's competitiveness is important especially when countries strive for bigger market shares as European countries are. The COVID-19 pandemic has had devastating effects on tourism and the entire tourism industry must be rethinking and reshaping given some opportunities and challenges to the entrepreneurs, local communities, local administrations, governments of competitiveness destinations. In this paper we measured if the Google and Apple mobility indices cand predict (or not) the movement of TTCI during pandemic compared with pre-pandemic TTCI ranks by using grey system theory and statistical methods. The aim of the paper is to validate the Grey Relational Analysis (GRA) as identifier of the good predictor (statistically significant for p-value< 0.05) for European tourism competitiveness (measured by TTCI) in particular conditions, especially before and during COVID-19 pandemic time by take into consideration the Google Mobility and Apple Mobility data and their relationship with overnight stays for 11 European countries. To validate the GRA as method for good and accurate predictor for tourism competitiveness for TTCI 2021 (during COVID-19 pandemic time) a GLM – General Linear Model ANOVA with interaction effects and Tukey HSD Post Hoc Multiple Comparisons was applied. Our results validated the powerful of GRA for tourism competitiveness, statistically significant according to GLM with interaction effects, and emphasis (especially for entrepreneurs) that the overnight stays will give the right rank on top of tourism competitiveness, prior to other ITC support as Google and Apple Mobility indices proved by reflection of overnights on TTCI 2021 – during pandemic. [ABSTRACT FROM AUTHOR]

Background: Independent prescribing (IP) has not been extensively investigated in community pharmacy (CP). Normalization process theory (NPT) constructs help explain how interventions are integrated into practice and include: 'coherence' (understanding), 'cognitive participation' (what promotes engagement), 'collective action' (integration with existing systems), and 'reflexive monitoring' (evaluation). Aim: To use NPT to investigate the integration of pharmacist IP in CP. Method: NHS Scotland Pharmacy First Plus (PFP) is a community pharmacy IP service. Questionnaire items were developed using the NPT derived Normalisation MeAsure Development (NoMAD) tool for an online survey of all PFP IP pharmacists. Demographic data were analysed descriptively and scale scores (calculated from item scores for the 4 NPT constructs) were used for inferential analysis. Results: There was a 73% (88/120) response rate. Greater than 90% 'strongly agreed'/'agreed' to NoMAD items relating to most NPT constructs. However, responses to 'collective action' items were diverse with more participants answering 'neither agree nor disagree' or 'disagree'. A statistically significant difference in NPT construct scale scores with significant p-values (ranging from p < 0.001 to p = 0.033) was shown on all the NPT constructs for the variable 'On average, how often do you consult with patients under the PFP service?'. Conclusion: This theory-based work offers perspectives on IP integration within CP. Despite its geographic focus this work offers insights relevant to wider contexts on IP integration. It shows 'collective action' focused 'organisation' and 'group process' challenges with a need for further work on staff training, resource availability and utilisation, working relationships, communication and management. [ABSTRACT FROM AUTHOR]

Purpose: The paper starts from an observation of a discrepancy between the ambitions for sustainable change in the agro-industry and the actual changes being implemented. We offer one possible explanation by investigating the organizational structures conditioning change in this industry. Design/methodology/approach: We apply a case study methodology, focusing on the Danish pig industry and its organizational conditions for change. Based on interviews and document analysis, and building on systems theory, we develop the concept of change structures, understood as decision premises that guide the change of further decision premises. Findings: The analysis suggests that the pig industry's change structures predominantly enable changes that cut costs and optimize the production, which may conflict with and possibly foreclose the changes needed to realize the industry's sustainable ambitions. This conflict and its implications are not acknowledged by the industry. Practical implications: The analysis indicates that the industry may be locked in its current form of organizational change. We suggest a way to overcome the lock-in by fostering organizational mechanisms that enable alternative interpretations to emerge internally. Without this, achieving the required sustainable change in the industry may hinge on stronger external regulation and support. Originality/value: Conceptually, the notion of change structures supplements actor-oriented analytical approaches that focus on change agents and sense-making. Empirically, we contribute with an analysis of the conditions of possibility for sustainable change in an important yet understudied industry in organization studies; namely, the conventional agro-industry. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to investigate the impact of an intervention on primary school students' construction of knowledge on ocean acidification and the development of their systems thinking. Eighty-five 11 to 12-year-old students from five different classes of two public primary schools in Greece participated in the 8-h intervention. The intervention included inquiry-based and knowledge-integration activities, and students worked in groups during all activities. Rich pictures, made by the groups at the beginning and the end of the intervention, were used to evaluate their progress in their knowledge concerning the carbon cycle, as well as in their systems thinking. Our findings showed that the intervention contributed to primary students' conceptual knowledge of the carbon cycle and the inclusion of ocean acidification in the carbon cycle. It also helped them improve their systems thinking, indicating that students' systems thinking at this age could be developed through formal instruction with interventions which emphasize content knowledge and use an earth systems approach. Moreover, our findings indicate that the systems thinking perspective can serve as an effective approach to help children better understand and critically engage with complex environmental issues, such as ocean acidification. [ABSTRACT FROM AUTHOR]

This paper reports results on the classification of traveling wave solutions, including nonnegative traveling wave solutions in a weak sense, in the spatial 1D degenerate parabolic equation. These are obtained through dynamical systems theory and geometric approaches (in particular, Poincaré compactification). Classification of traveling wave solutions means enumerating those that exist and presenting properties of each solution, such as its profile and asymptotic behavior. The results examine a different range of parameters included in the equation, using the same techniques as discussed in the earlier work [Y. Ichida, Discrete Contin. Dyn. Syst., Ser. B, 28 (2023), no. 2, 1116-1132]. In a clear departure from this previous work, the classification results obtained in this paper and the successful application of the known transformation also yield results for the classification of (weak) nonnegative traveling wave solutions for spatial 1D porous medium equations with special nonlinear terms. Finally, the bifurcations at infinity occur in the two-dimensional ordinary differential equations that characterize these traveling wave solutions are shown. [ABSTRACT FROM AUTHOR]

Practical combustors in furnaces, industrial heaters, and gas turbine engines face a sudden loss of flame due to rich blowout (RBO) at an extremely rich fuel-air mixture or lean blowout (LBO) at an extremely lean fuel-air mixture. Thus, the stability limits of the combustion regime are governed by RBO and LBO. In the present study, we focus on the dynamics of swirl-stabilized premixed combustion near lower and higher flammability limits, where the possibilities of LBO and RBO, respectively, are observed. Near RBO and LBO, we employ metrics from statistics and dynamical systems theory to characterize the transition in flame dynamics. We observe that the range of frequencies obtained using Fourier Transform near RBO and LBO is alike. The emergence of dominantly low-frequency oscillation near those blowout limits is investigated using Hilbert Transform. The mean frequency of the combustion system gradually reduces near both blowout limits due to behavioral oscillations prominently observed. The scaling property of flame oscillation is examined using the Hurst exponent, and we observe a decreasing trend of the parameter as combustion approaches both LBO and RBO. Therefore, for the gradual reduction of the Hurst exponent near both flammability limits, we can use the parameter as a precursor for both RBO and LBO. [ABSTRACT FROM AUTHOR]

The work is a brief review of the results obtained in nonautonomous dynamics based on the concept of uniform equivalence of nonautonomous systems. This approach to the study of nonautonomous systems was proposed in [24] and further developed in the works of the second author, and recently — jointly by both authors. Such an approach seems to be fruitful and promising, since it allows one to develop a nonautonomous analogue of the theory of dynamical systems for the indicated classes of systems and give a classification of some natural classes of nonautonomous systems using combinatorial type invariants. We show this for classes of nonautonomous gradient-like vector fields on closed manifolds of dimensions one, two, and three. In the latter case, a new equivalence invariant appears, the wild embedding type for stable and unstable manifolds [5, 8], as shown in a recent paper by the authors [19]. [ABSTRACT FROM AUTHOR]

In this paper, we study the localization of an electron in a binary quantum system formed by a pair of quantum dots (QDs). The traditional theoretical consideration of such systems is limited to the symmetrical case when QDs in such double quantum dot (DQD) are assumed identical in all respects. In this paper, we model the effects of breaking QD similarities in a DQD by studying two-dimensional (2D) DQDs as a double quantum well (DQW). This is done by solving the Schrödinger equation, with parameters chosen to describe an InAs/GaAs heterostructure. We calculate the energy spectrum of the electron confinement and the spectral distribution of localized/delocalized spatial states. Both symmetric and asymmetric QW shapes are considered and their effects are compared. The effects of symmetry breaking are explained within the framework of the two-level system theory. We delineate the QW weak and strong coupling cases in DQW. In particular, we show that the coherence in ideal DQW is unstable in the case of a weak QW coupling. Within the framework of the proposed approach, a charge qubit realized on a DQD is discussed and, as an example, a qubit based on an almost ideal DQD is proposed. [ABSTRACT FROM AUTHOR]

The existence of multiple biomolecular condensates inside living cells is a peculiar phenomenon not compatible with the predictions of equilibrium statistical mechanics. In this work, we address the problem of multiple condensates state (MCS) from a functional perspective. We combine Langevin dynamics, reaction-diffusion simulation, and dynamical systems theory to demonstrate that MCS can indeed be a function optimization strategy. Using Arp2/3 mediated actin nucleation pathway as an example, we show that actin polymerization is maximum at an optimal number of condensates. For a fixed amount of Arp2/3, MCS produces a greater response compared to its single condensate counterpart. Our analysis reveals the functional significance of the condensate size distribution which can be mapped to the recent experimental findings. Given the spatial heterogeneity within condensates and non-linear nature of intracellular networks, we envision MCS to be a generic functional solution, so that structures of network motifs may have evolved to accommodate such configurations. Biomolecular condensates often appear as a multi-droplet system inside living cells. Here, using multi-scale simulations, the authors show that such configurations are functionally more efficient in catalyzing cell signaling. [ABSTRACT FROM AUTHOR]

Theoretical models conventionally portray the consolidation of memories as a slow process that unfolds during sleep. According to the classical Complementary Learning Systems theory, the hippocampus (HPC) rapidly changes its connectivity during wakefulness to encode ongoing events and create memory ensembles that are later transferred to the prefrontal cortex (PFC) during sleep. However, recent experimental studies challenge this notion by showing that new information consistent with prior knowledge can be rapidly consolidated in PFC during wakefulness and that PFC lesions disrupt the encoding of congruent events in the HPC. The contributions of the PFC to memory encoding have therefore largely been overlooked. Moreover, most theoretical frameworks assume random and uncorrelated patterns representing memories, disregarding the correlations between our experiences. To address these shortcomings, we developed a HPC--PFC network model that simulates interactions between the HPC and PFC during the encoding of a memory (awake stage), and subsequent consolidation (sleeping stage) to examine the contributions of each region to the consolidation of novel and congruent memories. Our results show that the PFC network uses stored memory "schemas" consolidated during previous experiences to identify inputs that evoke congruent patterns of activity, quickly integrate it into its network, and gate which components are encoded in the HPC. More specifically, the PFC uses GABAergic long-range projections to inhibit HPC neurons representing input components correlated with a previously stored memory "schema," eliciting sparse hippocampal activity during exposure to congruent events, as it has been experimentally observed. [ABSTRACT FROM AUTHOR]

Securing complete control of complex systems comprised of tens of thousands of interconnected nodes holds immense significance across various fields, spanning from cell biology and brain science to human-engineered systems. However, depending on specific functional requirements, it can be more practical and efficient to focus on a pre-defined subset of nodes for control, a concept known as target control. While some methods have been proposed to find the smallest driver node set for target control, they either rely on heuristic approaches based on k-walk theory, lacking a guarantee of optimal solutions, or they are overly complex and challenging to implement in real-world networks. To address this challenge, we introduce a simple and elegant algorithm, inspired by the path cover problem, which efficiently identifies the nodes required to control a target node set within polynomial time. To practically apply the algorithm in real-world systems, we have selected several networks in which a specific set of nodes with functional significance can be designated as a target control set. The analysed systems include the complete connectome of the nematode worm C. elegans, the recently disclosed connectome of the Drosophila larval brain, as well as dozens of genome-wide metabolic networks spanning major plant lineages. The target control analysis shed light on distinctions between neural systems in nematode worms and larval brain insects, particularly concerning the number of nodes necessary to regulate specific functional systems. Furthermore, our analysis uncovers evolutionary trends within plant lineages, notably when examining the proportion of nodes required to control functional pathways. [ABSTRACT FROM AUTHOR]

The remarkable signal-detection capabilities of the auditory and vestibular systems have been studied for decades. Much of the conceptual framework that arose from this research has suggested that these sensory systems rest on the verge of instability, near a Hopf bifurcation, in order to explain the detection specifications. However, this paradigm contains several unresolved issues. Critical systems are not robust to stochastic fluctuations or imprecise tuning of the system parameters. Further, a system poised at criticality exhibits a phenomenon known in dynamical systems theory as critical slowing down, where the response time diverges as the system approaches the critical point. An alternative description of these sensory systems is based on the notion of chaotic dynamics, where the instabilities inherent to the dynamics produce high temporal acuity and sensitivity to weak signals, even in the presence of noise. This alternative description resolves the issues that arise in the criticality picture. We review the conceptual framework and experimental evidence that supports the use of chaos for signal detection by these systems, and propose future validation experiments. [ABSTRACT FROM AUTHOR]