Systems Theory Research Articles

Markovian dynamics for a quantum/classical system and quantum trajectories

Quantum trajectory techniques have been used in the theory of open systems as a starting point for numerical computations and to describe the monitoring of a quantum system in continuous time. We extend this technique to develop a general approach to the dynamics of quantum/classical hybrid systems. By using two coupled stochastic differential equations, we can describe a classical component and a quantum one which have their own intrinsic dynamics and which interact with each other. A mathematically rigorous construction is given, under the restriction of having a Markovian joint dynamics and of involving only bounded operators on the Hilbert space of the quantum component. An important feature is that, if the interaction allows for a flow of information from the quantum component to the classical one, necessarily the dynamics is dissipative. We show also how this theory is connected to a suitable hybrid dynamical semigroup, which reduces to a quantum dynamical semigroup in the purely quantum case and includes Liouville and Kolmogorov–Fokker–Planck equations in the purely classical case. Moreover, this semigroup allows to compare the proposed stochastic dynamics with various other proposals based on hybrid master equations. Some simple examples are constructed in order to show the variety of physical behaviors which can be described; in particular, a model presenting hidden entanglement is introduced.

Memory’s gatekeeper: The role of PFC in the encoding of congruent events

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.

Study on the Effect of Fly Ash on Mechanical Properties and Seawater Freeze–Thaw Resistance of Seawater Sea Sand Concrete

When using seawater and sea sand as mixes, the mechanical properties and durability of concrete are adversely affected because the raw materials themselves contain harmful ions. Fly ash is the tailings formed in the process of industrial production, the use of which does not require the burning of clinker, reducing CO2 emissions. Moreover, it belongs to a new type of cementitious materials with low emissions and high environmental protection. Fly ash enhances the properties of concrete and reduces the effect of harmful ions on concrete. Based on the above considerations, the corresponding specimens were prepared and subjected to cubic compressive strength, flexural strength, and seawater freezing and thawing resistance tests by using fly ash admixture as the main variable. A combination of macro-analysis and micro-analysis was used to investigate the effect of fly ash on the performance of seawater sea sand concrete. The results showed that fly ash significantly enhanced the mechanical properties and resistance to seawater freezing and thawing of seawater sea sand concrete. The best improvement in compressive strength and resistance to seawater freezing and thawing was achieved at a substitution rate of 20%. The maximum increase in compressive strength was 13.22%. The maximum reduction in mass loss rate was 57.26% and the strength loss rate was 43.14% after the specimens were subjected to seawater freezing and thawing 75 times. The maximum enhancement in flexural strength was 17.06% for a substitution rate of 10%. Through microanalysis, it can be seen that the incorporation of coal ash can enhance the compactness of concrete through the microaggregate effect as well as the volcanic ash reaction to promote the secondary hydration reaction, so as to strengthen the seawater freeze–thaw resistance of seawater sea sand concrete. Finally, the damage prediction model established using the mean GM (1, 1) model of gray system theory meets the requirements of the first level of prediction accuracy and can accurately predict the damage of seawater sea sand concrete under seawater freezing and thawing.

The logical structure of modular semantic theories of software systems

AbstractThis paper studies the structure of semantic theories over modular computational systems and applies the algebraic Theory of Institutions to provide a logical representation of such theories. A modular semantic theory is here defined by a cluster of semantic theories, each for a single program's module, and by a set of relations connecting models of different semantic theories. A semantic theory of a single module is provided in terms of the set of Σ‐models mapped from the category Th of Σ‐theories and generating a hierarchy of structures from an abstract model to a concrete model of data. The collection of abstract models representing different modules of a program is formalised as the category of institutions INS, where theory morphisms express refinements, integrations, and compositions between couples of modules. Finally, it is required that a morphism in INS at any level occurs iff the same morphism occurs at the lower level alongside the Th hierarchy.

Towards cyber-cooperatives: Studying the sharing economy of the tourism industry through an evolutionary approach to organizational cybernetics

Purpose: The lodging industry is transitioning to the online collaborative economy, with digital platforms mediating between hosts and guests. However, this has created significant inequalities between the platform management and the service providers. Objective. The paper proposes (a) to contribute to organisational cybernetics through evolutionary theory, (b) to analyse the emergence of platform cooperativism, and (c) to propose a platform cooperative based on the VSM, which we have called a cyber-cooperative. Design: Applying cybernetic evolutionary epistemology and the VSM, the article analyses the current state of the platform lodging industry and proposes the core characteristics of the cyber-cooperative. Findings: The article finds: a) it contributes to the theory of viable systems by integrating evolutionary theory; b) it uses the proposed theory to explain the developments in the collaborative economy of the lodging industry; c) it relates meme theory with the identity of the system and identifies the political ideas in cooperative organisations; d) it proposes the idea of the cyber-cooperative for developing the lodging industry. Originality: Evolutionary epistemology in organisational cybernetics, and the politics of identity in cooperativism are both novel approaches in the VSM. Type of paper: Research paper.

Chaotic Pattern and Solitary Solutions for the (21)-Dimensional Beta-Fractional Double-Chain DNA System

The dynamical behavior of the double-chain deoxyribonucleic acid (DNA) system holds significant implications for advancing the understanding of DNA transmission laws in the realms of biology and medicine. This study delves into the investigation of chaos patterns and solitary wave solutions for the (2+1) Beta-fractional double-chain DNA system, employing the theory of planar dynamical systems and the method of complete discrimination system for polynomials (CDSP). The results demonstrate a diverse spectrum of solitary wave solutions, sensitivity to perturbations, and manifestations of chaotic behavior within the system. Through the utilization of the complete discrimination system for polynomials, a multitude of novel solitary wave solutions, encompassing periodic, solitary wave, and Jacobian elliptic function solutions, were systematically constructed. The influence of Beta derivatives on the solutions was elucidated through parameter comparison analysis, emphasizing the innovative nature of this study. These findings underscore the potential of this system in unraveling various biologically significant DNA transmission mechanisms.

Understanding the factors related to how East and Southeast Asian immigrant youth and families access mental health and substance use services: A scoping review.

The objective of the review is to identify factors related to how East and Southeast Asian immigrant youth aged 12-24 and their families access mental health and substance use (MHSU) services. To address how East and Southeast Asian youth and their families access mental health and substance use services, a scoping review was conducted to identify studies in these databases: PubMed, MEDLINE (Ovid), EMBASE (Ovid), PsychINFO, CINAHL, and Sociology Collection. Qualitative content analysis was used to deductively identify themes and was guided by Bronfenbrenner's Ecological Systems Theory, the process-person-context-time (PPCT) model, and the five dimensions of care accessibility (approachability, acceptability, availability and accommodation, appropriateness, affordability). Seventy-three studies met the inclusion criteria. The dimensions of healthcare accessibility shaped the following themes: 1) Acceptability; 2) Appropriateness; 3) Approachability; 4) Availability and Accommodation. Bronfenbrenner's Ecological Systems Theory and the PPCT model informed the development of the following themes: 1) Immediate Environment/Proximal Processes (Familial Factors, Relationships with Peers; 2) Context (School-Based Services/Community Resources, Discrimination, Prevention, Virtual Care); 3) Person (Engagement in Services/Treatment/Research, Self-management); 4) Time (Immigration Status). The study suggests that there is a growing body of research (21 studies) focused on identifying acceptability factors, including Asian cultural values and the model minority stereotype impacting how East and Southeast Asian immigrant youth access MHSU services. This review also highlighted familial factors (16 studies), including family conflict, lack of MHSU literacy, reliance on family as support, and family-based interventions, as factors affecting how East and Southeast Asian immigrant youth access MHSU care. However, the study also highlighted a dearth of research examining how East and Southeast Asian youth with diverse identities access MHSU services. This review emphasizes the factors related to the access to MHSU services by East and Southeast Asian immigrant youth and families while providing insights that will improve cultural safety.

Filtered Right Coprime Factorization and Its Application to Control a Pneumatic Cylinder

The main objective of this research is to expand right coprime factorization based on operator theory in nonlinear systems. A novel method for right coprime factorization is proposed by introducing an operator that can deform the system’s response into an arbitrary shape. This enables the design of control systems that are highly effective against noise. As an application, we use a pneumatic stage. The effectiveness of this method is verified through simulations and real-world experiments.

Swedish student teachers’ perceptions of consequences of the teacher shortage for their future profession

The current teacher shortage is a global phenomenon, and it has spurred research from various perspectives. However, there is limited research on student teachers' perceptions, in particular in the Nordic countries. This study, therefore, is based on 75 student teachers' perceptions of the teacher shortage and its consequences for their future profession, their students, and society at large. Empirical data was analysed with reflexive thematic analysis and following Bronfenbrenner's ecological systems theory. The answers show great concern from all three perspectives. The conclusions are that the teacher shortage must be understood and addressed on a broad front that includes student teachers.

Seismic Risk Assessment and Analysis of Influencing Factors in the Sichuan–Yunnan Region

Investigating the distribution characteristics of earthquake disaster risks in the Sichuan–Yunnan region is of great importance for enhancing government emergency response capabilities and achieving sustainable regional development. This study, based on disaster systems theory, constructs a seismic risk evaluation index system for the Sichuan–Yunnan region and employs the entropy method to determine the comprehensive risk index for earthquake disasters across 37 prefecture-level cities. The findings reveal the following: (1) High-risk areas for disaster-causing factors are located in the Hengduan Mountain region and the North–South Mountain Range Valley Region; medium-risk areas are distributed along the northwestern edge of the Sichuan Basin; low-risk areas are situated in the eastern part of the Sichuan Basin and the Yunnan Plateau. (2) High-risk disaster-prone environments are found in the Hengduan Mountain region; medium-risk areas are present on the Yunnan Plateau and the western part of the North–South Mountain Range Valley Region; low-risk areas are in the Sichuan Basin. (3) High-vulnerability areas include the central Sichuan Basin and Kunming on the Yunnan Plateau; medium-vulnerability areas are located in the eastern and western parts of the Sichuan Basin; low-vulnerability areas are in the less developed parts of the Yunnan Plateau, the North–South Mountain Range Valley Region, and the Hengduan Mountain region. (4) High-risk seismic disaster areas are concentrated in the developed regions of the Sichuan Basin and the Yunnan Plateau; medium-risk areas are concentrated in the western part of the North–South Mountain Range Valley Region; low-risk areas are sporadically distributed in the eastern parts of the Sichuan–Yunnan region. (5) The vulnerability of the population, economy, and lifeline systems significantly explain the variation in seismic risk levels, all exceeding 0.70; the synergistic effects of disaster-causing factor danger, disaster-prone environment stability, and disaster-prone environment sensitivity are the most pronounced, with explanatory power exceeding 0.85 after factor interaction.

Building a comprehensive acupuncture clinical intervention system from individualized diagnosis and treatment to systematic design: reflections based on the modern rehabilitation treatment model

The acupuncture clinical practice system is presenting a diversity of intervention methods and intervention concepts as modern technological civilization progresses. Therefore, it is of practical significance to construct a comprehensive acupuncture clinical intervention system and to scientifically design and implement the intervention system. This article aims to combine the current development status of rehabilitation treatment models, starting from the perspective of systems theory, to explore the importance of constructing a comprehensive acupuncture intervention system and its implementation strategies, providing new ideas and directions for the modern development of acupuncture clinical practice.

Acetylene and Ethylene Adsorption during Floating Fe Catalyst Formation at the Onset of Carbon Nanotube Growth and the Effect of Sulfur Poisoning: a DFT Study.

Here, we investigated the adsorption of acetylene and ethylene on iron clusters and nanoparticles, which is a crucial aspect in the nascent phase of carbon nanotube growth by floating catalyst chemical vapor deposition (FCCVD). The effect of sulfur on adsorption was also studied due to its indispensable role in the process and its commonly known impact on metal catalyst poisoning. We performed systematic density functional theory (DFT) computations, considering numerous adsorption configurations and iron particles of various sizes (Fen, n = 3-10, 13, 55). We found that acetylene binds significantly more strongly than ethylene and prefers different adsorption sites. The presence of sulfur decreased the adsorption strength only in the immediate proximity of the adsorbate, suggesting that the effect of sulfur is mainly of steric origin while electronic effects play only a minor role. Higher sulfur coverage of the catalyst surface significantly weakened the binding of acetylene or ethylene. To further investigate this interaction, Bader's atoms in molecules (AIM) analysis and charge density difference (CDD) were used, which showed electron transfer from iron clusters or nanoparticles to the adsorbate molecules. The charge transfer exhibited a decreasing trend as sulfur coverage increased. These results can also contribute to the understanding of other iron-based catalytic processes involving hydrocarbons and sulfur, such as the Fischer-Tropsch synthesis.

Review of chaos in hair-cell dynamics

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.

Influence of Boards of Management Practices on Teachers Performance in Public Secondary Schools in Kenya: A Case of Manga Sub-County Nyamira County, Kenya

The purpose of the Basic Education Act No. 14 of 2013 is to increase professionalism in the administration of public elementary schools by establishing Boards of Management. The purpose of this research is to analyse the effect that Boards of Management policies have on student achievement in public primary schools in the Manga sub-county of Kisii County, Kenya. The study set out to answer several questions about the impact of various factors on students' academic success, including the availability of instructional resources, the quality of the school's physical environment, the quality of the teaching staff, and the effectiveness of the school's management's efforts to motivate its employees. The research was based on the open systems theory and the Path Goal Leadership Theory. The study used a variety of research strategies. Concurrent triangulation, a research strategy that blends quantitative and qualitative data, was used for this investigation. Principals, BOM members, and the Sub County Director of Education made up the study population. Sampling was performed using a stratified random sampling technique. Strata were designated as learning environments. Questionnaires and interview scripts were used to compile the data. The researcher piloted the surveys with two elementary schools in Manga Sub County that have certain demographic and social characteristics with the study area. Pearson's Product Coefficient was used to verify reliability. Co-efficient. If the dependability co-efficient was lower than 0.7, then the instruments would need to be improved. The instruments' validity and reliability were established by having them crafted under the watchful eyes of the supervisors and by consulting with subject-matter experts. Both qualitative and quantitative techniques were used to analyse the data. Descriptive and inferential statistics were used in the quantitative approaches. Descriptive statistics included measurements of central tendency and dispersion, such as means and standard deviations. Chi-square tests and spearman rank order correlations were used for inferential statistics. Analysing qualitative data required making sense of the responses and contrasting them with prior research. Frequency tables, percentages, and other numerical were used. Ethical considerations were taken into account during the investigation. The vast majority of respondents agreed that their schools' ability to provide necessary teaching and learning resources was facilitated by adhering to a schedule of events. The majority of respondents said that BOM members are capable of accurately forecasting and budgeting for physical infrastructure on their own. All respondents said that those working in BOM were trustworthy because of their moral rectitude and upright character. The research concluded that the Ministry of Education should institute safeguards to guarantee that only qualified individuals serve on public elementary school governing boards. It is imperative that steps be taken to guarantee the exchequer allocates sufficient funds for the purchase of physical infrastructure for public elementary schools

The Impact of Edge Computing on Real-Time Data Processing

Purpose: The study sought to explore the impact of edge computing on real-time data processing. Methodology: The study adopted a desktop research methodology. Desk research refers to secondary data or that which can be collected without fieldwork. Desk research is basically involved in collecting data from existing resources hence it is often considered a low cost technique as compared to field research, as the main cost is involved in executive’s time, telephone charges and directories. Thus, the study relied on already published studies, reports and statistics. This secondary data was easily accessed through the online journals and library. Findings: The findings reveal that there exists a contextual and methodological gap relating to the impact of edge computing on real-time data processing. Preliminary empirical review reveled that edge computing significantly reduced latency and enhanced efficiency in real-time data processing across various industries by bringing computational resources closer to data sources. It highlighted the technology's ability to handle large volumes of IoT-generated data, improve security by localizing data processing, and drive innovation and economic growth through new applications and services. Edge computing's decentralized approach proved essential for reliable and robust data handling, particularly in critical sectors like healthcare and finance, ultimately solidifying its importance in the digital transformation landscape. Unique Contribution to Theory, Practice and Policy: The Diffusion of Innovations Theory, Resource-Based View (RBV) and Sociotechnical Systems Theory may be used to anchor future studies on edge computing on real-time data processing. The study recommended expanding theoretical frameworks to include the unique aspects of edge computing, investing in robust edge infrastructure, and developing standardized protocols and best practices. It emphasized the need for government incentives and supportive regulatory frameworks to promote adoption, and suggested that academic institutions incorporate edge computing into curricula. Additionally, the study called for ongoing research to address emerging challenges and opportunities, ensuring continuous advancement and effective implementation of edge computing technologies.

Social Systems Theory and Family Business: A Perspective Article

Social Systems Theory and Family Business: A Perspective Article

Decoding of MDP Convolutional Codes over the Erasure Channel under Linear Systems Point of View

This paper attempts to highlight the decoding capabilities of MDP convolutional codes over the erasure channel by defining them as discrete linear dynamical systems, with which the controllability property and the observability characteristics of linear system theory can be applied, in particular those of output observability, easily described using matrix language. Those are viewed against the decoding capabilities of MDS block codes over the same channel. Not only is the time complexity better but the decoding capabilities are also increased with this approach because convolutional codes are more flexible in handling variable-length data streams than block codes, where they are fixed-length and less adaptable to varying data lengths without padding or other adjustments.

Strongly hyperbolic quasilinear systems revisited, with applications to relativistic fluid dynamics

We revisit the theory of first-order quasilinear systems with diagonalizable principal part and only real eigenvalues, what is commonly referred to as strongly hyperbolic systems. We provide a self-contained and simple proof of local well-posedness, in the Hadamard sense, of the Cauchy problem. Our regularity assumptions are very minimal. As an application, we apply our results to systems of ideal and viscous relativistic fluids, where the theory of strongly hyperbolic equations has been systematically used to study several systems of physical interest.

Strongly hyperbolic quasilinear systems revisited, with applications to relativistic fluid dynamics

We revisit the theory of first-order quasilinear systems with diagonalizable principal part and only real eigenvalues, what is commonly referred to as strongly hyperbolic systems. We provide a self-contained and simple proof of local well-posedness, in the Hadamard sense, of the Cauchy problem. Our regularity assumptions are very minimal. As an application, we apply our results to systems of ideal and viscous relativistic fluids, where the theory of strongly hyperbolic equations has been systematically used to study several systems of physical interest.

The ‘Coronavirus Crisis’ and xenophobia in South Africa: How did the pandemic affect anti‐immigrant sentiment?

AbstractThe impact of the COVID‐19 pandemic on xenophobia in South Africa is little understood. The Behavioural Immune System (BIS) theory would predict that hostility towards immigrants increases during periods of heightened pathogen stress. This BIS‐hypothesis is tested against the relative strength of three other possible drivers of anti‐immigrant sentiment. These included anger at the national lockdown system, intertemporal relative deprivation, and racial transformation ideology. For these tests nationally representative data (N = 2996), gathered during the height of the ‘Omicron’ wave, were used. Multivariate analysis showed that COVID‐19 exposure was not associated with more negative sentiments towards immigrants. Fear‐based reactions to the Coronavirus were, in fact, correlated with pro‐immigrant attitudes. Intertemporal relative deprivation and transformation orientations were much better predictors of anti‐immigrant sentiment than pathogen stress. These findings raised questions about the applicability of the BIS‐hypothesis in the context of the Coronavirus and suggest new avenues of academic inquiry.