Dynamical Theory Research Articles

Pulsed Laser-Bleaching Semiconductor and Photodetector.

Pulsed lasers alter the optical properties of semiconductors and affect the photoelectric function of the photodetectors significantly, resulting in transient changes known as bleaching. Bleaching has a profound impact on the control and interference of photodetector applications. Experiments using pump-probe techniques have made significant contributions to understanding ultrafast carrier dynamics. However, there are few theoretical studies to the best of our knowledge. Here, carrier dynamic models for semiconductors and photodetectors are established, respectively, employing the rectified carrier drift-diffusion model. The pulsed laser bleaching effect on seven types of semiconductors and photodetectors from visible to long-wave infrared is demonstrated. Additionally, a continuous bleaching method is provided, and the finite-difference time-domain (FDTD) method is used to solve carrier dynamic theory models. Laser parameters for continuous bleaching of semiconductors and photodetectors are calculated. The proposed bleaching model and achieved laser parameters for continuous bleaching are essential for several applications using semiconductor devices, such as infrared detection, biological imaging, and sensing.

The Use and Misuse of East Asian History in IR Theorizing

Abstract The past two decades have witnessed a wave of research into the history of East Asian international relations (IR). Scholars seek to broaden the historical frames of reference in IR for both theory testing and theory generation. The article reviews this recent trend, examining its limitations and exploring future agenda. In studying historical East Asian IR, scholars have different expectations regarding whether their research would support, complement, or undermine mainstream Western IR. The spatial and temporal scope of their historical inquiries, as well as theoretical ambitions, therefore, differ significantly. Scholars no longer treat all East Asian history as simply one case, but as multiple cases with divergent patterns, and they recognize that the system consisted not solely of China but of multiple actors. In addition to contrasting East Asia with Western Europe, they explore also the similarities between East Asia and other non-Western regions. To advance the agenda, however, scholars must scrupulously navigate three tensions. They are: the tension between the “East” and “West”; the tension between the two disciplines of history and IR; and the tension between past and present. Future studies, therefore, must broaden their horizons in order to better transcend ethnocentrism and exceptionalism, refine their methodology both to avoid selection bias and conduct more sophisticated comparisons, and to maintain a proper distance from contemporary politics. Most importantly, they should combine high-quality historical research with cutting-edge IR theoretical trends to construct dynamic theories that could be applied to other regions.

The Interplay of Corporate Social Responsibility, Innovation Capability, Organizational Learning, and Sustainable Value Creation: Does Stakeholder Engagement Matter?

At the crossroads of innovation and responsibility, our study delves into CSR’s pivotal role in steering organizations toward sustainable value creation. Combining the frameworks of stakeholder theory, the resource-based view, and dynamic capabilities theory, this study examines the influence of corporate social responsibility (CSR) in enhancing sustainable value creation (SVC), with a keen focus on how organizational learning (OL) and innovation capability (IC) mediate this relationship and the degree to which stakeholder engagement (SE) moderates the impact of CSR on OL, IC, and SVC. Using a quantitative research approach, 416 managers in the Turkish manufacturing sector (e.g., textiles, building materials, and food processing firms) were surveyed using electronic and physical questionnaires. To test the research model, AMOS 24 was employed. The results confirmed that CSR positively influences SVC, OL, and IC; OL and IC positively influence SVC; OL and IC partially mediate the relationship between CSR and SVC. Likewise, the findings suggest that stakeholder engagement (SE) plays a moderate role in strengthening the relationship between CSR and organizational learning (OL), CSR and innovation capability (IC), and CSR and sustainable value creation (SVC), with increased SE enhancing the positive effect of CSR on OL, IC, and SVC. This study explains the complex ways that CSR enhances SVC, focusing on OL and IC’s mediating roles and SE’s moderating effects. It offers manufacturing sectors in Turkey useful information for promoting sustainability and innovation.

Mapping the South China Sea Conflict through the Dynamic Framework Theory on Conflict Prevention and Peacebuilding

he dynamics of the South China Sea conflict hold the potential for certain levels of escalation. The complexity of the conflict in the South China Sea needs to be specifically unraveled through the theory of the dynamic framework for conflict prevention and peace. This involves identifying the components that trigger and drive the conflict, which can then serve as a reference for formulating measures to prevent the escalation of the conflict. In this study, the South China Sea conflict is the primary object of exploration using the dynamic framework theory for conflict identification. The dynamic conflict framework has interrelated components that can be synthesized to determine that the South China Sea conflict is in a critical situation

DIGITAL LEADERSHIP AND CREATIVE PERFORMANCE IN TOURISM AND HOTEL ENTERPRISES: LEVERAGING STRATEGIC AGILITY AND ORGANIZATIONAL LEARNING CULTURE

The aim of this study is to explore the effect of digital leadership (DL) on creative performance (CP) by investigating the mediating roles of strategic agility (SA) and organizational learning culture (OLC) in tourism and hospitality industry. The study analyzed 320 responses from middle-level management at five-star hotels and category-A travel agencies in Egypt using the PLS-SEM technique and WarpPLS statistical software 7.0. Findings reveal that digital leadership positively affects creative performance, strategic agility, and organizational learning culture. In addition, CP is positively affected by SA and OLC. Moreover, findings confirm the mediation effects of strategic agility and organizational learning culture in the DL→CP relationship. The study provides practical insights for tourism and hospitality enterprises using Dynamic Capabilities Theory to enhance performance and agility in the digital age.

A Frequency Up-Conversion Piezoelectric Energy Harvester Shunted to a Synchronous Electric Charge Extraction Circuit.

A frequency up-conversion piezoelectric energy harvester (FUC-PEH) consists of a force amplifier, a piezoelectric stack, a low-frequency oscillator (LFO), and a stop limiter. The force amplifier generates the amplification of stress on the piezoelectric stack. The LFO, comprising a spring and a mass block, impacts the stop limiter during vibration to induce high-frequency oscillations within the piezoelectric stack. In this paper, we represent and simplify the FUC-PEH as a lumped-parameter model based on piezoelectric material constitutive equations and structural dynamic theories. Using the electromechanical analogy, we developed an equivalent circuit model (ECM) of the FUC-PEH. A parametric study was performed to investigate the impact of system parameters, such as spring stiffness and concentrated mass, on the FUC-PEH performance. The collision-induced amplitude truncation (AT) effect enlarges the operation bandwidth. ECM simulations show that low-frequency input excitation is converted into a high-frequency output response, enhancing the energy conversion efficiency. Furthermore, we aimed to improve the FUC-PEH's performance using a synchronous electric charge extraction (SECE) circuit. Using the ECM approach, we established a system-level model that considers the electromechanical coupling behavior. The simulation results provide insights into the performance of FUC harvesters with SECE circuits and offer valuable design guidance.

Dark energy and dark matter interaction: A nonlinear dynamical system study

This paper presents a methodical dynamical analysis of the Big Bang model, taking into account dark matter and an arbitrary form of dark energy. Nevertheless, why dynamic analysis? The primary advantage of the dynamical analysis approach is that it obviates the necessity to precisely solve the system for every individual dependent variable. Instead, it enables the prediction of the overall evolutions. In this regard, there are some powerful tools of non-dynamical systems (theorems, perturbation, etc.) which can help us a lot. The model under consideration is a nonlinear system with two dimensions (2D). In order to investigate this, we employ a sophisticated form of nonlinear dynamical systems theory in our research. We have delved into the full potential of nonlinear dynamical system theory known until now in our work. This analysis has produced very interesting solutions, which are in quite a contrast with the linear analysis approach. The stability of the system is considered at length, and the corresponding evolutions of the universe are also discussed consequently. A handful number of figures are given to visualize the behavior of the evolutions. The plots that are presented here are vector field plots and a new plotting technique initiated by us and used in our earlier papers. Interestingly, our work indicates the universe might resemble “phantom” evolution. Also, among the fixed points of our model, one is able to escape the singular situation called “Big Rip”.

A prediction method for blade deformations of large-scale FVAWTs using dynamics theory and machine learning techniques

There is renewed interest in floating vertical axis wind turbines (FVAWTs) as offshore wind turbines progressively increase in size and move into deeper waters. To explore the potential of large-scale FVAWTs for future commercialization, it is crucial to investigate blade deformations using an accurate and effective method. In this study, we developed a hybrid model, namely, the SVST-ANN, which integrates dynamic theory and machine learning techniques to predict blade deformations. Specifically, an artificial neural network (ANN) module is incorporated into the slack coupled vertical axis wind turbine simulation tool (SVST), which significantly reduces the total computational time. A comparative study was conducted between the SVST-ANN model and the traditional SVST model, employing a 10 MW helical-type FVAWT as an example. The results show that the SVST-ANN model can accurately and efficiently predict blade deformations. The maximum errors for the maximum value, average value, and standard deviation across all nodes are minimal, with a corresponding computational time reduction of approximately 60 %. This study provides a novel method for investigating the dynamic behavior of the FVAWTs, which is more effective for calculating the elastic deformations of blades than traditional numerical methods.

Prioritizing drug targets by perturbing biological network response functions.

Therapeutic interventions are designed to perturb the function of a biological system. However, there are many types of proteins that cannot be targeted with conventional small molecule drugs. Accordingly, many identified gene-regulatory drivers and downstream effectors are currently undruggable. Drivers and effectors are often connected by druggable signaling and regulatory intermediates. Methods to identify druggable intermediates therefore have general value in expanding the set of targets available for hypothesis-driven validation. Here we identify and prioritize potential druggable intermediates by developing a network perturbation theory, termed NetPert, for response functions of biological networks. Dynamics are defined by a network structure in which vertices represent genes and proteins, and edges represent gene-regulatory interactions and protein-protein interactions. Perturbation theory for network dynamics prioritizes targets that interfere with signaling from driver to response genes. Applications to organoid models for metastatic breast cancer demonstrate the ability of this mathematical framework to identify and prioritize druggable intermediates. While the short-time limit of the perturbation theory resembles betweenness centrality, NetPert is superior in generating target rankings that correlate with previous wet-lab assays and are more robust to incomplete or noisy network data. NetPert also performs better than a related graph diffusion approach. Wet-lab assays demonstrate that drugs for targets identified by NetPert, including targets that are not themselves differentially expressed, are active in suppressing additional metastatic phenotypes.

An investigation of the impact of intellectual capital on entrepreneurial performance: A moderated mediation analysis on global firms

The stability of multinational corporations is under threat due to the intensifying turbulence of global competition, which prevents intellectual capital from actively promoting performance. To meet the challenges brought by diverse and tumultuous environmental contexts, multinationals urgently need to develop new approaches that will resolve risks at headquarters and mitigate the adverse effects of the crisis on cross-border business operations. Building on the resource-based theory and dynamic capabilities theory, this research aims to seek possible solutions that would optimize the structure of intellectual capital in various subsidiary regions so as to maximize their effectiveness in sustaining parent company performance in the presence of turmoil. Taking listed multinational corporations (MNCs) as the research subject, this paper explored the impact of intellectual capital of foreign subsidiaries on their parent company performance through the mediating and moderating dynamics of slack resources and institutional distance respectively. Furthermore, we explored the above mechanism by comparing a developed-economy MNC and a developing-economy MNC contexts. Through investigating a dataset of 1237 listed foreign subsidiaries during the period 2012 to 2021, we found that foreign subsidiaries' intellectual capital behaved in largely different mechanisms comparing developed and developing economies such that, subsidiaries' intellectual capital in developed economies was found to be contributing to parent company performance, whereas, subsidiaries' intellectual capital in developing economies fail to play a positive role on parent company performance. Meanwhile, the results showed that, absorbed slack played an indirect-only mediating role on the relationship between subsidiaries' intellectual capital and parent company performance in developing countries, and unabsorbed slack resources played a competitive mediating role for the full sample. Whereas, institutional distance fails to play moderate role in the effect of foreign subsidiaries' intellectual capital on parent company performance. Our study has implications for MNCs in the post-COVID era. It can help them minimize external threat and develop strategies and measures to maximize the structure of intellectual capital in different host locations, thereby enhancing their multinational performance.

A Dynamic Entropy Approach Reveals Reduced Functional Network Connectivity Trajectory Complexity in Schizophrenia.

Over the past decade and a half, dynamic functional imaging has revealed low-dimensional brain connectivity measures, identified potential common human spatial connectivity states, tracked the transition patterns of these states, and demonstrated meaningful transition alterations in disorders and over the course of development. Recently, researchers have begun to analyze these data from the perspective of dynamic systems and information theory in the hopes of understanding how these dynamics support less easily quantified processes, such as information processing, cortical hierarchy, and consciousness. Little attention has been paid to the effects of psychiatric disease on these measures, however. We begin to rectify this by examining the complexity of subject trajectories in state space through the lens of information theory. Specifically, we identify a basis for the dynamic functional connectivity state space and track subject trajectories through this space over the course of the scan. The dynamic complexity of these trajectories is assessed along each dimension of the proposed basis space. Using these estimates, we demonstrate that schizophrenia patients display substantially simpler trajectories than demographically matched healthy controls and that this drop in complexity concentrates along specific dimensions. We also demonstrate that entropy generation in at least one of these dimensions is linked to cognitive performance. Overall, the results suggest great value in applying dynamic systems theory to problems of neuroimaging and reveal a substantial drop in the complexity of schizophrenia patients' brain function.

Student Engagement with Teacher Written Corrective Feedback among Chinese Private College Students of Varying Language Proficiencies

While the efficacy of teacher written corrective feedback (WCF) has been extensively explored, a research gap exists in examining the disparities in how low-proficiency (LP) and high-proficiency (HP) students receive such feedback in second language (L2) writing. Through an analysis of five writing tasks distributed over a 16-week course, this research explored the affective, behavioral, and cognitive dimensions of student engagement with WCF. Six Chinese EFL sophomores, three designated as LP and three as HP students, were selected through purposive sampling. Data collection methods included analysis of students’ L2 writing tasks and stimulated recall sessions. The findings illustrate varying engagement patterns, highlighting LP students’ frustrations and HP students’ reflective and constructive interactions with feedback. These patterns are interpreted through the lens of sociocultural, social cognitive, student engagement, and complex dynamic systems theories, offering a multifaceted framework for understanding the influence of WCF on L2 writing proficiency. These findings also contribute to language learning pedagogy by highlighting the importance of tailored feedback strategies that address the comprehensive dimensions of student engagement to enhance the pedagogical effectiveness of WCF in fostering language proficiency and engagement in EFL settings.

On the role of seamounts in upwelling deep-ocean waters through turbulent mixing

Turbulent mixing in the ocean exerts an important control on the rate and structure of the overturning circulation. However, the balance of processes underpinning this mixing is subject to significant uncertainties, limiting our understanding of the overturning's deep upwelling limb. Here, we investigate the hitherto primarily neglected role of tens of thousands of seamounts in sustaining deep-ocean upwelling. Dynamical theory indicates that seamounts may stir and mix deep waters by generating lee waves and topographic wake vortices. At low latitudes, stirring and mixing are predicted to be enhanced by a layered vortex regime in the wakes. Using three realistic regional simulations spanning equatorial to middle latitudes, we show that layered wake vortices and elevated mixing are widespread around seamounts. We identify scalings that relate mixing rate within seamount wakes to topographic and hydrographic parameters. We then apply such scalings to a global seamount dataset and an ocean climatology to show that seamount-generated mixing makes an important contribution to the upwelling of deep waters. Our work thus brings seamounts to the fore of the deep-ocean mixing problem and urges observational, theoretical, and modeling efforts toward incorporating the seamounts' mixing effects in conceptual and numerical ocean circulation models.

Optimal control of oscillatory neuronal models with applications to communication through coherence

Macroscopic oscillations in the brain are involved in various cognitive and physiological processes, yet their precise function is not completely understood. Communication through coherence (CTC) theory proposes that these rhythmic electrical patterns might serve to regulate the information flow between neural populations. Thus, to communicate effectively, neural populations must synchronize their oscillatory activity, ensuring that input volleys from the presynaptic population reach the postsynaptic one at its maximum phase of excitability. We consider an Excitatory–Inhibitory (E–I) network whose macroscopic activity is described by an exact mean-field model. The E–I network receives periodic inputs from either one or two external sources, for which effective communication will not be achieved in the absence of control. We explore strategies based on optimal control theory for phase–amplitude dynamics to design a periodic control that sets the target population in the optimal phase to synchronize its activity with a specific presynaptic input signal and establish communication. The control mechanism resembles the role of a higher cortical area in the context of selective attention. To design the control, we use the phase–amplitude reduction of a limit cycle and leverage recent developments in this field in order to find the most effective control strategy regarding a defined cost function. Furthermore, we present results that guarantee the local controllability of the system close to the limit cycle.

Digital Leadership and Sustainable Competitive Advantage: Leveraging Green Absorptive Capability and Eco-Innovation in Tourism and Hospitality Businesses

This study explores the influence of digital leadership (DL) on sustainable competitive advantage (SCA) in tourism and hospitality businesses, focusing on green absorptive capability (GAC) and eco-innovation (EI) as mediators. This study focused on middle-line management in travel agencies and hotels in Saudi Arabia. A total of 323 valid responses were collected and analyzed using WarpPLS 7.0, a PLS-SEM analysis tool. DL positively affected SCA, GAC, and EI. In addition, SCA was positively impacted by GAC and EI. Furthermore, this study found that GAC and EI significantly mediated the DL→SCA relationship. This study enhances the Dynamic Capabilities Theory, offering valuable insights for tourism and hospitality managers to utilize digital strategies and environmental initiatives for eco-conscious market competitiveness.

Causalized Convergent Cross Mapping and Its Implementation in Causality Analysis.

Rooted in dynamic systems theory, convergent cross mapping (CCM) has attracted increased attention recently due to its capability in detecting linear and nonlinear causal coupling in both random and deterministic settings. One limitation with CCM is that it uses both past and future values to predict the current value, which is inconsistent with the widely accepted definition of causality, where it is assumed that the future values of one process cannot influence the past of another. To overcome this obstacle, in our previous research, we introduced the concept of causalized convergent cross mapping (cCCM), where future values are no longer used to predict the current value. In this paper, we focus on the implementation of cCCM in causality analysis. More specifically, we demonstrate the effectiveness of cCCM in identifying both linear and nonlinear causal coupling in various settings through a large number of examples, including Gaussian random variables with additive noise, sinusoidal waveforms, autoregressive models, stochastic processes with a dominant spectral component embedded in noise, deterministic chaotic maps, and systems with memory, as well as experimental fMRI data. In particular, we analyze the impact of shadow manifold construction on the performance of cCCM and provide detailed guidelines on how to configure the key parameters of cCCM in different applications. Overall, our analysis indicates that cCCM is a promising and easy-to-implement tool for causality analysis in a wide spectrum of applications.

Seizing Capabilities and Performance of Supermarkets in Kenya

In Kenya the supermarkets provide market access for the manufacturers’ and small and medium enterprises’ products. In the recent past renowned supermarket brands such as Nakumatt, Tuskys, Choppies and Uchumi have collapsed due to underperformance. This paper examines the influence of seizing capabilities on the performance of supermarkets in Kenyan cities. The study was anchored on the dynamic capability theory (DCT). The study was grounded on positivism research philosophy and adopted crossectional descriptive research design. A structured questionnaire was used to collect primary data from 629 licensed supermarkets. A sample size of 304 respondents from a population of 1258 senior managers was used. Stratified random sampling method was used to select the sample size in Nairobi, Mombasa, Kisumu, and Nakuru. Descriptive statistics such as mean and standard deviation and inferential statistics which included correlation and regression are the statistical tools that were used to analyse the data. Statistical package for social scientists (SPSS) software version 28 was utilized to explore the data. The findings demonstrated that seizing capabilities have a statistically significance (β = 0.511, t = 12.501, p < 0.05) influence on the performance of supermarkets in the Kenyan cities. The study demonstrated that it is vital for supermarkets’ management to consciously design business models and allocate resources that can facilitate the optimal exploitation of new business opportunities to add value to the supermarkets. The management should develop a resource mobilization strategy to fund long term projects that are aimed at seizing opportunities that will improve supermarket’s survival and performance.

Spectral features of a single type III burst in the frequency range of 10–70 MHz

Spectral properties of a single type III burst in the wide frequency band from 10 to 70 MHz are studied in detail. It is shown that electrons corresponding to different levels of type III emission move with different velocities. Moreover, these electron velocities decrease from the maximum value, which corresponds to the 0.1 level of the maximum type III flux at its front, to the minimum value, corresponding to the 0.1 level of the maximum type III flux at its back. The velocity of electrons corresponding to the maximum type III flux was approximately 0.31 c. This value equals 0.6 of maximum velocity, and, namely, it was predicted by the gas dynamic theory of electron propagation through the coronal plasma. In addition, we adduce arguments that the type III radio emission is the harmonic emission. In supposition that type III electrons move through the Newkirk coronal plasma, we find electron velocities for every level of the type III burst. The duration dependence on frequency obtained from the observations is close to Elgaroy–Lingstad dependence. We discuss the contribution of electron velocity dispersion to the type III burst duration. In addition, we derived type III flux dependence on frequency in the frequency bands of 10–33 MHz and 33–62 MHz.

The Ripple Effects of the Illegitimacy of War

Abstracts Recent data show systematic changes in the diplomacy and practice of war. Conquests, peace treaties, declarations of war, and state boundary changes have declined or disappeared. There are still wars, but they are increasingly fait accomplis, and their outcomes are often not recognized as legal. How can we explain this wide-ranging but seemingly contradictory transformation? Existing accounts, such as those based on a territorial integrity norm, do not adequately explain these changes. This paper uses norm dynamics theory to show that all of these changes can be explained as ‘ripple effects’ of war becoming illegitimate as a way to solve international disputes. The kinds of rhetorical justifications states can convincingly give for engaging in violence have changed. States are navigating this changed international social environment through legitimacy management behaviors. The paper specifies three types of ripple effect, Reframing, Displacement, and Consistency-Maintenance, corresponding to changes in what states say, the actions they perform, and how the audience reacts. We show how this theory unifies all of the existing data into a single explanatory framework. We also apply the theory to the decline of peace treaties to show how ripple effects play out in more detail.

Violation of a Leggett-Garg Inequality Using Ideal Negative Measurements in Neutron Interferometry.

Leggett-Garg inequalities (LGIs) have been proposed in order to assess how far the predictions of quantum mechanics defy "macroscopic realism." With LGIs, correlations of measurements performed on a single system at different times are described. We report on an experiment that demonstrates the violation of an LGI with neutrons. The final measured value of the Leggett-Garg correlator K=1.120±0.007(stat)±0.019(sys), obtained in a neutron interferometric experiment, is clearly above the limit K=1 predicted by macrorealistic theories. The experimental results are analyzed within the framework of dynamical theory of neutron diffraction, evidently reproducing the obtained values.