Academic literature on the topic 'Complex Dynamic Systems Theory (CDST)'
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Journal articles on the topic "Complex Dynamic Systems Theory (CDST)"
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Fogal, Gary G. "Second language writing from a complex dynamic systems perspective." Language Teaching 55, no. 2 (April 2022): 193–210. http://dx.doi.org/10.1017/s0261444821000410.
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This work provides a chronological and thematic account of empirical studies and position papers on second language (L2) writing scholarship from a complex dynamic systems theory (CDST) perspective. As a theoretical framework, CDST was formally introduced into applied linguistics research by Diane Larsen-Freeman in 1994 (Larsen-Freeman, 1994). However, more than a decade passed before CDST-L2 writing studies emerged in the literature, with Larsen-Freeman (2006) frequently cited as the first related publication. Initially, scholarship focused primarily on the quality of linguistic output (e.g., measures of complexity, accuracy, and fluency, or CAF) in North American and European contexts. Since these early foci, studies have expanded to cover a range of constructs and contexts that employ increasingly sophisticated and diverse research methods (for a recent collection of studies, see Fogal & Verspoor, 2020). In this time, a CDST approach to L2 writing research has matured alongside a general CDST view of language change that has contributed, through empirical studies, to understanding the nonlinear, adaptive, context dependent, and complex and dynamic nature of L2 development (see Hiver et al., 2021, for an overview).
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Stotz, Quinton, and Walcir Cardoso. "Applying Complex Dynamic Systems Theory to Identify Dynamic Properties of Plurilingual Repertoires." TESL Canada Journal 38, no. 2 (March 10, 2022): 140–70. http://dx.doi.org/10.18806/tesl.v38i2.1360.
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Language repertoires have been traditionally construed as a set of chronologically determined compartments (first language, second language, etc.), a scheme which upholds several validity and ethical issues when operationalized in research and education (Ortega, 2019). Complex dynamic systems theory (also complexity theory, here CDST) has been hailed as one solution moving forward, but its applicability to plurilingual settings requires further testing. This exploratory study contributes by examining whether inherent properties of complex dynamic systems manifest in the perceptions that plurilinguals have as their language systems change over time. Using retrodictive qualitative modelling (Dörnyei, 2014), this study discerned the developmental trajectory of changing language systems by working backwards through data collected during an observation window. Over a 3-month period, three plurilingual individuals assessed their language systems through weekly surveys and participated in open-ended interviews. A three-stage phenomenological analysis evaluated the data against CDST’s theoretical prism to identify five CDST properties (attractor states, phase shifts, co-adaptation, self-organization, and emergence) in the participants’ perceptions of their changing repertoires. Results indicate that plurilingual repertoires exhibit the aforementioned dynamics, although evidence for emergence was less certain. Importantly, this study shows that CDST dynamics are discernible in an individual’s perception of their language development over time.
Les répertoires langagiers se comprennent traditionnellement comme un ensemble de compartiments déterminés chronologiquement (première langue, deuxième langue, etc.), un mécanisme qui maintient plusieurs problèmes de validité et d’éthique quand il est opérationnalisé dans la recherche et l’enseignement (Ortega, 2019). La théorie des systèmes dynamiques complexes (également appelée théorie de la complexité, ici TSDC) a été acclamée comme une solution pour avancer, mais son applicabilité à des contextes plurilingues devra être testée davantage. L’étude exploratoire suivante apporte sa contribution en examinant le fait de savoir si les propriétés inhérentes aux systèmes dynamiques complexes se manifestent dans les perceptions que les plurilingues ont de leurs systèmes au fur et à mesure que leurs systèmes de langue changent avec le temps. En se servant de la modélisation de la rétrodiction qualitative (Dörnyei, 2014), cette étude discerne la trajectoire de développement de systèmes langagiers changeants en travaillant à l’envers par le biais de données recueillies pendant une fenêtre d’observation. Pendant une période de trois mois, trois personnes plurilingues ont évalué leurs systèmes langagiers au moyen de sondages hebdomadaires et ont participé à des entrevues ouvertes. Une analyse phénoménologique en trois étapes a évalué les données par rapport au prisme théorique de la TSDC afin d’identifier cinq propriétés de la TSDC (l’état d’attractivité, les changements de phases, la co-adaptation, l’auto-organisation et l’émergence) dans la perception que les participants avaient de leurs répertoires changeants. Les résultats indiquent que les répertoires plurilingues démontrent les dynamiques susmentionnées, bien que les preuves de l’émergence soient moins certaines. De façon importante, cette étude montre que les dynamiques de la TSDC sont discernables dans la perception que chaque personne se fait du développement de leur langue avec le temps.
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Jackson, Daniel O. "Working memory and second language development: A complex, dynamic future?" Studies in Second Language Learning and Teaching 10, no. 1 (March 29, 2020): 89–109. http://dx.doi.org/10.14746/ssllt.2020.10.1.5.
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Working memory (WM) is inherently dynamic and complex, being a multi-faceted system that links storage and processing components; yet it is widely understood as internal. Hence, in second language (L2) research, its connection to complex dynamic systems theory (CDST) remains underspecified. This paper seeks to bridge a gap between CDST and WM in L2 research. First, definitions of WM are reviewed, along with evidence for its relationship to L2 outcomes. Next, a brief overview of CDST highlights its metatheoretical and methodological implications. Three perspectives are presented to illustrate how WM can be viewed in terms of major tenets in CDST. These consider WM effects as: (1) context-dependent, (2) interrelated with those of other variables, and (3) amenable to change across the lifespan. Despite this reappraisal, numerous challenges remain. Thus, in addition to noting research opportunities, the paper also considers measurement issues, such as the determination of boundaries and selection of appropriate timescales. In closing, while WM studies have shown its influence on L2 proficiency and processing, to more fully understand its dynamic nature, what is needed is further research on the reciprocal influences of bilingual development and changes in WM components, such as control of attention.
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Yu, Hanjing, and Wander Lowie. "Dynamic Paths of Complexity and Accuracy in Second Language Speech: A Longitudinal Case Study of Chinese Learners." Applied Linguistics 41, no. 6 (July 23, 2019): 855–77. http://dx.doi.org/10.1093/applin/amz040.
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Abstract The present study investigated the developmental patterns of Chinese EFL(AQ) learners’ oral language in terms of complexity and accuracy and looked into the dynamic interactions between them within the framework of Complex Dynamic Systems Theory (CDST). The data were analysed using dynamic analyses (moving min–max graphs, moving correlations and Monte Carlo Simulations). It was found that, firstly, at the group level, the general developmental trends of both complexity and accuracy showed improvements. Secondly, at the individual level, the developmental patterns were non-linear and dynamic with high degrees of variability, and individual language development was influenced by the initial states. Thirdly, the analyses revealed a complex interplay between complexity and accuracy, which gradually shifted from a clearly competitive relationship during the early stages to a supportive relationship in later stages. This shift in interaction shows that complexity goes hand in hand with accuracy, which corroborates the interconnectedness of subsystems as one of the major characteristics of CDST. The findings confirm the applicability of CDST approaches to L2 oral development and carry valuable implications for CDST theory development and oral language teaching.
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Larsen-Freeman, Diane. "Thoughts on the Launching of a New Journal: A Complex Dynamic Systems Perspective." Journal for the Psychology of Language Learning 1, no. 1 (June 23, 2019): 67–82. http://dx.doi.org/10.52598/jpll/1/1/5.
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The launching of The Journal for the Psychology of Language Learning is a signal achievement. I begin this commentary by speculating on why it is that the Psychology of Language Learning (PLL) has enjoyed such vigor of late. I expect that one reason is the coming together of a critical mass of researchers and strong leaders over their shared interests. A second reason may be that a new way of looking at familiar phenomena was introduced in the form of complex dynamic systems theory (CDST). Building on this supposition, I proceed to recommend extending CDST thinking in some new ways in PLL. These ways are phenomenological, relational, processual, and transdisciplinary. I conclude by urging the PLL community to remain connected with other areas of applied linguistics so that it may continue to contribute to a knowledge-building community.
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Hiver, Phil, and Ali H. Al-Hoorie. "Transdisciplinary research methods and complexity theory in applied linguistics: introduction to the special issue." International Review of Applied Linguistics in Language Teaching 60, no. 1 (February 16, 2021): 1–6. http://dx.doi.org/10.1515/iral-2021-0020.
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Abstract Complexity theory/dynamic systems theory (CDST) has captured the imagination of many in the field of applied linguistics (Larsen-Freeman, Diane & Lynne Cameron. 2008. Complex systems and applied linguistics. Oxford: Oxford University Press; Ortega, Lourdes & Zhao Hong Han (eds.). 2017. Complexity theory and language development: In celebration of Diane Larsen-Freeman. Amsterdam: John Benjamins). As recent syntheses of the growing number of CDST-informed strands of applied linguistics research illustrates, it has emerged as an important influence on applied linguists’ thinking (see Larsen-Freeman, Diane. 2017. Complexity theory: The lessons continue. In Lourdes Ortega & Zhao Hong Han (eds.), Complexity theory and language development: In celebration of Diane Larsen-Freeman, 11–50. Amsterdam: John Benjamins). The fact that CDST has continued to permeate questions throughout the field is to be expected and welcomed.
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Amerstorfer, Carmen M. "The dynamism of strategic learning: Complexity theory in strategic L2 development." Studies in Second Language Learning and Teaching 10, no. 1 (March 29, 2020): 21–44. http://dx.doi.org/10.14746/ssllt.2020.10.1.2.
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Learners of foreign languages (L2s) apply strategies to support learning processes and L2 development. They select strategies according to their individual needs and preferences and adjust their strategic actions to suit situational circumstances and contextual conditions. A holistic investigation of strategic L2 learning processes requires the integration of numerous interconnected, flexibly-interacting influences, which are at constant interplay with each other and whose development is difficult to predict. Validated as effective in other fields of applied linguistics, complex dynamic systems theory (CDST) can also provide an appropriate frame for researching strategic L2 learning. Based on state-of-the-art methodological guidance for complexity research, this article presents the re-analysis of empirical data from a previous study through a complexity lens. It further examines the suitability of CDST in strategy research, explores its practical value, and demonstrates that a complexity perspective can generate new, profound information about strategic learning.
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ROKOSZEWSKA, KATARZYNA. "The relationships between the average semester growth rates of lexical sophistication in L2 English writing at secondary school: A learner corpus analysis." Glottodidactica. An International Journal of Applied Linguistics 48, no. 1 (July 1, 2021): 81–102. http://dx.doi.org/10.14746/gl.2021.48.1.05.
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In line with Complex Dynamic Systems Theory (CDST), the aim of the paper is to examine dynamics and causality among the growth rates of lexical sophistication in L2 writing development. The study was based on The Written English Developmental Corpus of Polish Learners (WEDCPL) which consists of over 1,900 essays composed during 21 repeated measurements by 100 learners over three years (2014–2017) at secondary school. Lexical sophistication, operationalised as different frequency levels, was analysed with the Lextutor software (Cobb 2014). The results indicated that the learners relied on the first frequency level. The monthly growth rates (MGRs) of the frequency levels were variable but no significant peaks were registered. The relationships between the average semester growth rates (ASGRs) revealed competition between the first and higher frequency levels, and some support between the higher levels. Thus, developing learners’ lexis beyond the first level counteracts the production of lexically unsophisticated texts and supports the use of more advanced words.
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Rokoszewska, Katarzyna. "Accuracy and complexity as connected growers in L2 English speech at secondary school – a case study of a good, average, and poor language learner." Neofilolog, no. 56/1 (March 31, 2021): 71–90. http://dx.doi.org/10.14746/n.2021.56.1.6.
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Complex Dynamic Systems Theory (CDST), which originated in the natural sciences, has recently been applied to second language acquisition, underlining the interdisciplinary character of this humanistic discipline. According to this theory, language is a complex dynamic system consisting of subsystems which develop in a non-linear way, forming different kinds of supportive, competitive, or conditional relationships. What is more, these subsystems compete for the learner’s limited resources, which causes trade-offs within and between language subsystems, such as complexity, accuracy, and fluency, especially in speech. The present paper constitutes a part of a short series of articles which present different aspects of the same longitudinal case study on the development of L2 English speech at secondary school. The aim of this paper is to examine the relationships between language accuracy and a number of specific measures of syntactic complexity, i.e. general sentence complexity, subordination, coordination, and nominalisation; as well as lexical complexity, i.e. lexical density, sophistication, and variation, in the case of a good, average, and poor language learner at secondary school. In general, the results showed that the relationships between the selected variables fluctuated over time and often differed in the case of a good, average, and poor language learner.
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Rokoszewska, Katarzyna Joanna. "Fluency and complexity as coupled growers in speaking English at secondary school – A case study of a good, average, and poor language learner." Linguistics Beyond and Within (LingBaW) 6 (December 30, 2020): 160–74. http://dx.doi.org/10.31743/lingbaw.11838.
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One of the main assumptions of Complex Dynamic Systems Theory (CDST) is that internally complex language subsystems develop non-linearly while entering different kinds of supportive, competitive, conditional, or dual relationships which are characterised by trade-offs caused by learners’ restricted cognitive processing, especially in foreign language speech. The present paper belongs to a short series of articles which examines various aspects of the development of L2 English speech at secondary school on basis of the same longitudinal, exploratory, and corpus-based case study. The aim of this paper is to investigate the dynamics of the relationships between fluency and both syntactic and lexical complexity in the speech of a good, average, and poor language learner at the level of secondary school. Syntactic complexity was investigated in terms of general sentence complexity, subordination, coordination, and nominalisation, whereas lexical complexity was construed in terms of lexical density, sophistication, and variation. In general, the results indicated predominantly supportive relationships between fluency and different measures of syntactic complexity but competitive or dual relationships between fluency and lexical complexity. However, the relationships between the selected variables fluctuated over time and often differed in the case of a good, average, and poor language learner.
Dissertations / Theses on the topic "Complex Dynamic Systems Theory (CDST)"
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Beach, Joni Leigh. "A Grounded Theory Study of Systems Theory and Clothing and Textiles Theories for the Development of a Dynamic, Complex Human Systems Theory." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/29373.
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Metatheory, a study of theories, was the focus of this research study. A qualitative, grounded theory research design was used to examine documents on systems theory found outside the field of Clothing and Textiles (CT) and the social psychological theories used within CT. Recognizing the dynamic, complex nature of the human system and its interaction with multiple other systems led to the question of: What multidimensional theoretical framework would address this complexity and provide an expanded view for research and education in the field of CT?
Data were collected from documentary materials pertaining to systems theory and CT theories by the researcher in a library search of the literature. Four domains were identified from the data that were collected and analyzed. The domains were Relationship, Process, Organization, and Outcomes. Then, a holistic, systemic theoretical framework and the Human-Environment Systems model were developed from the integration of systems theory and the CT theories. The model was designed to give a general, abstract visual representation of the theoretical concepts of a holistic, systemic view of the human-environment unit. A discussion of the complex societal issue of body image and eating disorders in females served to illustrate the use of the proposed theoretical framework and model. Recommendations were made for future exploration of the use of a holistic perspective for research and educational practices in the field of CT in order to address dynamic, complex human-environment problems.Ph. D.
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Zhang, Daili. "Multi-agent based control of large-scale complex systems employing distributed dynamic inference engine." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33963.
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Increasing societal demand for automation has led to considerable efforts to control large-scale complex systems, especially in the area of autonomous intelligent control methods. The control system of a large-scale complex system needs to satisfy four system level requirements: robustness, flexibility, reusability, and scalability. Corresponding to the four system level requirements, there arise four major challenges. First, it is difficult to get accurate and complete information. Second, the system may be physically highly distributed. Third, the system evolves very quickly. Fourth, emergent global behaviors of the system can be caused by small disturbances at the component level.
The Multi-Agent Based Control (MABC) method as an implementation of distributed intelligent control has been the focus of research since the 1970s, in an effort to solve the above-mentioned problems in controlling large-scale complex systems. However, to the author's best knowledge, all MABC systems for large-scale complex systems with significant uncertainties are problem-specific and thus difficult to extend to other domains or larger systems. This situation is partly due to the control architecture of multiple agents being determined by agent to agent coupling and interaction mechanisms. Therefore, the research objective of this dissertation is to develop a comprehensive, generalized framework for the control system design of general large-scale complex systems with significant uncertainties, with the focus on distributed control architecture design and distributed inference engine design.
A Hybrid Multi-Agent Based Control (HyMABC) architecture is proposed by combining hierarchical control architecture and module control architecture with logical replication rings. First, it decomposes a complex system hierarchically; second, it combines the components in the same level as a module, and then designs common interfaces for all of the components in the same module; third, replications are made for critical agents and are organized into logical rings. This architecture maintains clear guidelines for complexity decomposition and also increases the robustness of the whole system.
Multiple Sectioned Dynamic Bayesian Networks (MSDBNs) as a distributed dynamic probabilistic inference engine, can be embedded into the control architecture to handle uncertainties of general large-scale complex systems. MSDBNs decomposes a large knowledge-based system into many agents. Each agent holds its partial perspective of a large problem domain by representing its knowledge as a Dynamic Bayesian Network (DBN). Each agent accesses local evidence from its corresponding local sensors and communicates with other agents through finite message passing. If the distributed agents can be organized into a tree structure, satisfying the running intersection property and d-sep set requirements, globally consistent inferences are achievable in a distributed way. By using different frequencies for local DBN agent belief updating and global system belief updating, it balances the communication cost with the global consistency of inferences. In this dissertation, a fully factorized Boyen-Koller (BK) approximation algorithm is used for local DBN agent belief updating, and the static Junction Forest Linkage Tree (JFLT) algorithm is used for global system belief updating.
MSDBNs assume a static structure and a stable communication network for the whole system. However, for a real system, sub-Bayesian networks as nodes could be lost, and the communication network could be shut down due to partial damage in the system. Therefore, on-line and automatic MSDBNs structure formation is necessary for making robust state estimations and increasing survivability of the whole system. A Distributed Spanning Tree Optimization (DSTO) algorithm, a Distributed D-Sep Set Satisfaction (DDSSS) algorithm, and a Distributed Running Intersection Satisfaction (DRIS) algorithm are proposed in this dissertation. Combining these three distributed algorithms and a Distributed Belief Propagation (DBP) algorithm in MSDBNs makes state estimations robust to partial damage in the whole system.
Combining the distributed control architecture design and the distributed inference engine design leads to a process of control system design for a general large-scale complex system. As applications of the proposed methodology, the control system design of a simplified ship chilled water system and a notional ship chilled water system have been demonstrated step by step. Simulation results not only show that the proposed methodology gives a clear guideline for control system design for general large-scale complex systems with dynamic and uncertain environment, but also indicate that the combination of MSDBNs and HyMABC can provide excellent performance for controlling general large-scale complex systems.
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Davis, Jacqueline Topsy Mengersen. "The role of culture in children's sex-typed preferences for colours, toys, and affordances : a systems theory approach." Thesis, University of Cambridge, 2019. https://www.repository.cam.ac.uk/handle/1810/289913.
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Children's sex-typed preferences for colours and toys are well-established, and often function as markers of sex-typicality in research on the development of sex-typed behaviour. However, children's sex-typed colour and toy preferences have not been tested cross-culturally, or in remote unindustrialised cultural settings. The present thesis tested children's preferences for sex-typed toys in four cultural settings: Shipibo villages in the Lake Imiria region of the Peruvian Amazon; kastom villages in the mountains of Tanna Island in Vanuatu in the South Pacific; children attending school in Lenakel town on Tanna Island; and in a large industrialised city in Australia. It also tested children's colour preferences in three of these cultures. It was hypothesised that colour and toy preferences would show some similarities across cultures, and further, that similarities in toy preferences across cultures would be explained by the different types of play afforded by the toys. Results suggested that colour preferences, specifically, a sex difference in preference for pink, are specific to industrialised cultures. Results further suggested that some sex differences in toy preferences replicate in different cultures, and that the relationship between toy preferences and children's preferences for play affordances is a potentially important area for further research. The present thesis also provided two demonstrations of how new statistical methods, adapted from complex and dynamic systems theory, could be applied to the cross-cultural dataset. A machine learning method suggested that sex, more than culture, affects children's sex-typed toy preferences. A multistate dynamic method further suggested that sex, more than culture, affects the dynamics of children's toy choices.
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Nebel, Anne Louise. "Emerging from the task : a complex dynamic systems theory investigation of English L2 learner- writing task engagement and the phenomenon of complexity." Thesis, Lancaster University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.658215.
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A number of studies of interest to TBL T and SLA researchers have examined L2 task complexity in pedagogical and assessment contexts by using models of cognitive complexity to predict and account for complexity in learner performances as responses to tasks (e.g. Chalhoub-Deville, 2001; Elder, Iwashita & McNamara, 2002; Robinson, 2001, 2005; Skehan & Foster, 1999,2001; Wigglesworth, 2001). These experimental studies manipulated task variables in order to identify how those variables impact complexity-as determined by quantitative measures of fluency, accuracy and complexity-in the resulting performances. The findings have varied considerably, both within and across studies, however, drawing their underlying assumptions into critical view and creating an opportunity for other theories and methods in applied linguistics to bring new light to the phenomenon of complexity. Complex dynamic systems theory provides a useful framework for better understanding complexity in this applied linguistics problem space (Larsen-Freeman & Cameron, 2008).
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Alharbi, Fahad. "The Dynamics of the L2 Motivational Self System among Saudi Study Abroad Students." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6672.
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Adult second language acquisition takes time over an extended period of time during which the L2 motivation of learners goes through periods of ups and downs. Dörnyei, MacIntyre and Henry (2015) recognized the inherently dynamic nature of L2 motivation and called for adopting the Complex Dynamic System Theory (CDST) when studying this phenomenon. While using a CDST perspective, this mixed method study drew on Dörnyei’s (2009b) model of the Motivational Self System to examine the L2 motivation of 86 Saudi study-abroad students. Also, the construct of the Anti-ought to Self (Thompson, 2015) and aspects of the Appraisal Theory (Schumann, 2001) were adopted to guide this examination. The results of the study showed that the L2 motivation of the participants fell into four main motivational patterns. Also, some of the participants shifted into new attractor states over the course of their academic semester. Another important finding was that the Anti-ought to Self appeared as an important construct. The results of the standard multiple regressions showed that the amount of the variance in the Intended Learning Effort that was accounted for by the Anti-ought to Self alone exceeded the amount of the variance accounted for by the other explanatory variables put together. Also, the analysis of the quantitative and qualitative data showed that the use of the Appraisal Theory improved the construct validity of the Learning Experiences. The implications of these findings and future directions of the L2 motivational research were also discussed in the study.
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Despois, Julien. "Situations d'inclusion de jeunes enfants avec des troubles du spectre autistique à l'école maternelle : évolution de la participation sociale des élèves et des représentations professionnelles des enseignants." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMR080.
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Cette thèse propose d’étudier les situations d’inclusion des jeunes enfants avec TSA scolarisés à l’école maternelle. Plus précisément, cette thèse poursuit trois objectifs. Tout d’abord, cette étude visait à étudier la dynamique d’interaction adultes – élèves avec TSA inclus à l’école maternelle en fonction de l’activité proposée (accueil et ateliers). Ensuite, il s’agissait d’analyser l’évolution de cette dynamique au cours d’une année scolaire. Enfin, le dernier objectif était de mieux comprendre l’évolution des représentations professionnelles des enseignantes à propos des situations d’inclusion. Dans cette optique, huit classes de maternelle accueillant des élèves avec TSA ont d’abord été observées. Puis l’observation s’est poursuivie sur deux classes au cours d’une année scolaire. Parallèlement à ces observations, des entretiens semi-directifs ont été menés avec les enseignantes, à trois moments de l’année, afin d’accéder à leurs représentations professionnelles. L’analyse des données d’observation à partir des State Space Grids indique qu’il n’existe aucune différence entre les activités, ni pour la participation sociale des enfants, ni pour la guidance des adultes. Par ailleurs, les observations réalisées au cours de l’année révèlent que les situations d’inclusion évoluent de manière singulière d’un type d’activité à un autre et d’une situation d’inclusion à une autre. Parallèlement, les résultats des entretiens montrent que les représentations professionnelles évoluent différemment au cours du temps selon l’enseignant et selon la situation d’inclusion dans laquelle ils se trouvent. Ces résultats montrent une diversité des situations d’inclusion à l’école maternelle et interrogent les dispositifs de formation dans le cadre de l’école inclusive. Les conclusions des différentes études nous amènent à proposer un modèle d’analyse tridimensionnel des situations d’inclusion de jeunes enfants avec TSA à l’école maternelleThis thesis studies the situations of inclusion of young children with ASD enrolled in preschool. More precisely, this thesis has three objectives. First, this study aims to study the dynamics of the interaction between adults and pupils with ASD included in a nursery school, according to the proposed activity (free play and teacher-led activities). Then, the evolution of this dynamic was analyzed during a school year. Finally, the last objective was to better understand the evolution of teachers' professional representations of situations of inclusion. In this perspective, eight kindergarten classes welcoming a child with ASD were first observed. Then, the observation continued in (ou with?) two classes during a school year. In parallel to these observations, semi-directive interviews were conducted with teachers at three different times of the year in order to address their professional representations. The analysis of observational data from State Space Grids indicates that there is no difference between the activities for either the social participation of children or adult guidance. Moreover, the observations made during the year reveal that the situations of inclusion evolve in a singular way from one type of activity to another, and from one situation of inclusion to another. At the same time, the interview’s results show that professional representations change differently over time depending on the teacher and the inclusion situation in which they find themselves. These results show a diversity of situations of inclusion in preschool and question the training systems within the framework of inclusive schools. The conclusions of the various studies lead us to propose a three-dimensional analysis model of the situations of inclusion of young children with ASD in preschool
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Marques, Pedro Jorge da Silva. "A metÃfora e a metonÃmia sob a perspectiva dos sistemas dinÃmicos complexos e da teoria fractal no processo de conceitualizaÃÃo da violÃncia urbana na cidade de Fortaleza-CE." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=11786.
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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃA metÃfora sempre ocupou um lugar de destaque nos estudos do significado e, com o avanÃo das pesquisas em LinguÃstica Cognitiva, essa figura apresenta-se mais evidente quando posta em relaÃÃo com a metonÃmia, que ganha pouco destaque nas pesquisas acadÃmicas. Nesse contexto, a presente pesquisa tem como objetivos: (i) estabelecer a primazia da metonÃmia sobre a metÃfora por meio da anÃlise dinÃmica do discurso dos participantes de grupos focais, ao discutirem a violÃncia urbana na cidade de Fortaleza; (ii) verificar se as relaÃÃes metonÃmicas dÃo-se tanto em nÃvel contextual como de enunciado; e (iii) demonstrar que as metonÃmias sÃo responsÃveis pela emergÃncia de grande parte dos veÃculos metafÃricos, tÃo importantes para a construÃÃo do sentido. Para tanto, fez-se necessÃrio discutir as principais abordagens dos fenÃmenos à luz da teoria dos Sistemas DinÃmicos Complexos, ancorados em Larsen-Freeman (1997); Larsen-Freeman e Cameron (2008), na teoria fractal, com fundamentos em Paiva (2010) e Mandelbrot (1982), assim como Capra (2006). Esse referencial teÃrico serviu de base para verificarmos a hipÃtese de que grande parte das metÃforas serà oriunda de metonÃmia e de que as relaÃÃes que contribuem para a emergÃncia dessa figura deram-se tanto em nÃvel contextual como de enunciado, surgindo de forma fragmentada no discurso real dos participantes dos grupos focais. AlÃm disso, a pesquisa propÃe-se tambÃm a descrever o processo de conceitualizaÃÃo da violÃncia urbana com base nos critÃrios do paradigma da complexidade, mostrando sua importÃncia para as atuais pesquisas. Para dar consistÃncia à nossa discussÃo, embasamo-nos em autores como Goosens (1990, 1995), Barcelona (1997) e Radden (2003) que tambÃm discutem a complexa relaÃÃo entre metÃfora e metonÃmia. Nosso estudo està pautado em uma pesquisa qualitativa e teÃrica, que nos permite refletir acerca da primazia da metonÃmia em relaÃÃo à metÃfora, analisando a transcriÃÃo de trÃs grupos focais que discutiram a questÃo da violÃncia urbana na cidade de Fortaleza-CE. A anÃlise permitiu constatar, atà o momento que, em alguns casos, no processo de conceitualizaÃÃo da violÃncia urbana, a metÃfora tem procedÃncia na metonÃmia, visto que as relaÃÃes que estruturam a metonÃmia, como parte pelo todo, instituiÃÃo pelos responsÃveis, efeito pela causa, entre outros, permeiam tanto o enunciado como o contexto da discussÃo dos participantes dos grupos focais. Isso nos fez chegar à conclusÃo de que uma sÃrie de metÃforas provÃm de metonÃmias o que mostra que, apesar de a metÃfora e a metonÃmia interagirem entre si, em alguns casos, hà primazia desta sobre aquela.
The metaphor has always occupied an important place in meaning studies and with the advances on Cognitive Linguistics researches this figure presents itself more evident when put in relation with metonym, which has less importance on academic researches. In this context, this very work aims: (i) establish the primacy of metonym over metaphor by the dynamic discourse analysis of focal group participants when discussing urban violence in the city of Fortaleza; (ii) verify if the metonymic relations appear both in context and wording; and (iii) demonstrate that metonyms are responsible for the emerging of great part of metaphorical vehicles, so important to the construction of meaning. Thus, it was necessary to discuss the main approaches of these phenomena in light of Complex Dynamic Systems theory, anchored on Larsen-Freeman (1997); Larsen-Freeman e Cameron (2008), on fractal theory, based in Paiva (2010) e Mandelbrot (1982), as Capra (2006). This theoretical reference served as base to verify the hypothesis that great part of metaphors emerge from metonyms and that the relations contribute to the emerging of that both contextual and wording levels arise fragmented in the real discourse of focal group participants. Furthermore, the research proposes itself to also describe the process of conceptualization of urban violence based in the criteria of complexity paradigm, showing its importance to the current researches. To give consistency to that discussion we based ourselves in authors such as Goosens (1990, 1995), Barcelona (1997) and Radden (2003), who also discuss the complex relation between metaphor and metonym. Our study is ruled by a qualitative and theoretical research that allows us to reflect about the primacy of metonym over metaphor, analyzing the transcription of three focal groups that discussed the urban violence in the city of Fortaleza. The analysis allowed until this moment the ascertainment that in some cases, in the process of conceptualization, the metaphor arises from metonym, as relations that structure metonym, such as take a tree for a forest, institution for its responsible ones, effect by cause, permeate both wording and context of the discussion of the focal group participants. This made us come to the conclusion that a series of metaphors come from metonyms, what shows that although metaphor and metonym interact themselves, there is a primacy of the second over the first in some cases.
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Martinet, Lucie. "Réseaux dynamiques de terrain : caractérisation et propriétés de diffusion en milieu hospitalier." Thesis, Lyon, École normale supérieure, 2015. http://www.theses.fr/2015ENSL1010/document.
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Durant cette thèse, nous nous sommes intéressés aux outils permettant d'extraire les propriétés structurelles et temporelles de réseaux dynamiques ainsi que les caractéristiques de certains scénarios de diffusion pouvant s'opérer sur ces réseaux. Nous avons travaillé sur un jeu de données spécifiques, issu du projet MOSAR, qui comporte entre autre le réseau de proximité des personnes au cours du temps durant 6 mois à l'hôpital de Berk-sur-mer. Ce réseau est particulier dans le sens où il est constitué de trois dimensions: temporelle, structurelle par la répartition des personnes en services et fonctionnelle car chaque personne appartient à une catégorie socio-professionnelle. Pour chacune des dimensions, nous avons utilisé des outils existants en physique statistique ainsi qu'en théorie des graphes pour extraire des informations permettant de décrire certaines propriétés du réseau. Cela nous a permis de souligner le caractère très structuré de la répartition des contacts qui suit la répartition en services et mis en évidence les accointances entre certaines catégories professionnelles. Concernant la partie temporelle, nous avons mis en avant l'évolution périodique circadienne et hebdomadaire ainsi que les différences fondamentales entre l'évolution des interactions des patients et celle des personnels. Nous avons aussi présenté des outils permettant de comparer l'activité entre deux périodes données et de quantifier la similarité de ces périodes. Nous avons ensuite utilisé la technique de simulation pour extraire des propriétés de diffusion de ce réseau afin de donner quelques indices pour établir une politique de préventionIn this thesis, we focus on tools whose aim is to extract structural and temporal properties of dynamic networks as well as diffusion characteristics which can occur on these networks. We work on specific data, from the European MOSAR project, including the network of individuals proximity from time to time during 6 months at the Brek-sur-Mer Hospital. The studied network is notable because of its three dimensions constitution : the structural one induced by the distribution of individuals into distinct services, the functional dimension due to the partition of individual into groups of socio-professional categories and the temporal dimension.For each dimension, we used tools well known from the areas of statistical physics as well as graphs theory in order to extract information which enable to describe the network properties. These methods underline the specific structure of the contacts distribution which follows the individuals distribution into services. We also highlight strong links within specific socio-professional categories. Regarding the temporal part, we extract circadian and weekly patterns and quantify the similarities of these activities. We also notice distinct behaviour within patients and staff evolution. In addition, we present tools to compare the network activity within two given periods. To finish, we use simulations techniques to extract diffusion properties of the network to find some clues in order to establish a prevention policy
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Yang, Ang Information Technology & Electrical Engineering Australian Defence Force Academy UNSW. "A networked multi-agent combat model : emergence explained." Awarded by:University of New South Wales - Australian Defence Force Academy. School of Information Technology and Electrical Engineering, 2007. http://handle.unsw.edu.au/1959.4/38823.
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Simulation has been used to model combat for a long time. Recently, it has been accepted that combat is a complex adaptive system (CAS). Multi-agent systems (MAS) are also considered as a powerful modelling and development environment to simulate combat. Agent-based distillations (ABD) - proposed by the US Marine Corp - are a type of MAS used mainly by the military for exploring large scenario spaces. ABDs that facilitated the analysis and understanding of combat include: ISAAC, EINSTein, MANA, CROCADILE and BactoWars. With new concepts such as networked forces, previous ABDs can implicitly simulate a networked force. However, the architectures of these systems limit the potential advantages gained from the use of networks. In this thesis, a novel network centric multi-agent architecture (NCMAA) is pro-posed, based purely on network theory and CAS. In NCMAA, each relationship and interaction is modelled as a network, with the entities or agents as the nodes. NCMAA offers the following advantages: 1. An explicit model of interactions/relationships: it facilitates the analysis of the role of interactions/relationships in simulations; 2. A mechanism to capture the interaction or influence between networks; 3. A formal real-time reasoning framework at the network level in ABDs: it interprets the emergent behaviours online. For a long time, it has been believed that it is hard in CAS to reason about emerging phenomena. In this thesis, I show that despite being almost impossible to reason about the behaviour of the system by looking at the components alone because of high nonlinearity, it is possible to reason about emerging phenomena by looking at the network level. This is undertaken through analysing network dynamics, where I provide an English-like reasoning log to explain the simulation. Two implementations of a new land-combat system called the Warfare Intelligent System for Dynamic Optimization of Missions (WISDOM) are presented. WISDOM-I is built based on the same principles as those in existing ABDs while WISDOM-II is built based on NCMAA. The unique features of WISDOM-II include: 1. A real-time network analysis toolbox: it captures patterns while interaction is evolving during the simulation; 2. Flexible C3 (command, control and communication) models; I 3. Integration of tactics with strategies: the tactical decisions are guided by the strategic planning; 4. A model of recovery: it allows users to study the role of recovery capability and resources; 5. Real-time visualization of all possible information: it allows users to intervene during the simulation to steer it differently in human-in-the-loop simulations. A comparison between the fitness landscapes of WISDOM-I and II reveals similarities and differences, which emphasise the importance and role of the networked architecture and the addition of strategic planning. Lastly but not least, WISDOM-II is used in an experiment with two setups, with and without strategic planning in different urban terrains. When the strategic planning was removed, conclusions were similar to traditional ABDs but were very different when the system ran with strategic planning. As such, I show that results obtained from traditional ABDs - where rational group planning is not considered - can be misleading. Finally, the thesis tests and demonstrates the role of communication in urban ter-rains. As future warfighting concepts tend to focus on asymmetric warfare in urban environments, it was vital to test the role of networked forces in these environments. I demonstrate that there is a phase transition in a number of situations where highly dense urban terrains may lead to similar outcomes as open terrains, while medium to light dense urban terrains have different dynamics
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Buyukates, Yesim. "Characterization of the plankton community in the lower Rincon Delta: Investigations regarding new approaches to management." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/1312.
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In light of increasing harmful algal blooms and the need to protect human health and aquatic resources, proactive management approaches merit further study. For this purpose I conducted field samplings to characterize plankton community composition and laboratory experiments to test some approaches to new management schemes in the lower Rincon Delta. On site measurements and microscopic analysis showed that environmental parameters and plankton community composition varied considerably among sampling stations and sampling dates. A recent modeling study suggested that manipulation of freshwater inflow to estuaries might prevent phytoplankton blooms and enhance secondary productivity. To test this theory I conducted three semi-continuous design and flow-through incubation design experiments using natural plankton assemblages. I investigated the effect of two different pulsing regimes of inflow and nutrient loading on zooplankton densities, and phytoplankton biomass and diversity. Despite differences in zooplankton structure and phytoplankton community composition between the two experiment designs, the results confirmed that pulsed inflows might alter plankton dynamics. My findings showed that 3-day pulse treatments consistently supported greater zooplankton densities and higher phytoplankton species diversity when compared to 1-day pulse treatments. In addition, accumulation of phytoplankton biovolume remained low during 3-day pulse treatments. Differences in zooplankton performance between 3-day pulse and 1-day pulse inflow treatments were likely due to the ability of phytoplankton to uptake and store greater amounts of nutrients under conditions of 3-day pulse inflow. This resulted in food of higher quality for zooplankton, and might have supported greater zooplankton population growth rates. Additionally, in an attempt to understand the mechanisms leading to high biodiversity in aquatic ecosystems, I built a resource-storage model and studied the effects of resource-storage on competition of multiple phytoplankton species on multiple abiotic resources. I compared this model with a well-established multi-species competition model. My results showed that for certain species combinations a resource-storage-based model can generate dissimilar outcomes when compared to a model without resource-storage.
Books on the topic "Complex Dynamic Systems Theory (CDST)"
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Fogal, Gary G., and Marjolijn H. Verspoor, eds. Complex Dynamic Systems Theory and L2 Writing Development. Amsterdam: John Benjamins Publishing Company, 2020. http://dx.doi.org/10.1075/lllt.54.
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Herbert, Praehofer, and Kim Tag Gon, eds. Theory of modeling and simulation: Integrating discrete event and continuous complex dynamic systems. 2nd ed. San Diego: Academic Press, 2000.
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Southeast Geometry Seminar (15th 2009 University of Alabama at Birmingham). Geometric analysis, mathematical relativity, and nonlinear partial differential equations: Southeast Geometry Seminars Emory University, Georgia Institute of Technology, University of Alabama, Birmingham, and the University of Tennessee, 2009-2011. Edited by Ghomi Mohammad 1969-. Providence, Rhode Island: American Mathematical Society, 2013.
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Fogal, Gary G., and Marjolijn H. Verspoor. Complex Dynamic Systems Theory and L2 Writing Development. Benjamins Publishing Company, John, 2020.
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Fogal, Gary G., and Marjolijn H. Verspoor. Complex Dynamic Systems Theory and L2 Writing Development. Benjamins Publishing Company, John, 2020.
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Fogal, Gary G., and Marjolijn H. Verspoor. Complex Dynamic Systems Theory and L2 Writing Development. Benjamins Publishing Company, John, 2020.
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Boukas, El-Kébir, and Roland P. Malhamé. Analysis, Control and Optimization of Complex Dynamic Systems. Springer, 2014.
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(Editor), El Kébir Boukas, and Roland P. Malhamé (Editor), eds. Analysis, Control and Optimization of Complex Dynamic Systems (Gerad 25th Anniversary). Springer, 2005.
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Analysis, Control and Optimization of Complex Dynamic Systems (Gerad 25th Anniversary). Springer, 2005.
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Aihara, Kazuyuki, Tetsushi Ueta, and Jun-ichi Imura. Analysis and Control of Complex Dynamical Systems: Robust Bifurcation, Dynamic Attractors, and Network Complexity. Springer, 2016.
Find full textBook chapters on the topic "Complex Dynamic Systems Theory (CDST)"
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Toffoli, Denyze. "Complex Dynamic Systems Theory (CDST)." In Informal Learning and Institution-wide Language Provision, 5–22. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-37876-9_1.
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Verspoor, Marjolijn, and Wander Lowie. "Complex Dynamic Systems Theory (CDST)." In The Routledge Handbook of Second Language Acquisition and Corpora, 189–200. London; New York: Routledge, 2020. |: Routledge, 2020. http://dx.doi.org/10.4324/9781351137904-17.
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Byrnes, Heidi. "Chapter 10. Envisioning L2 writing development in CDST under a curricular optic." In Complex Dynamic Systems Theory and L2 Writing Development, 241–70. Amsterdam: John Benjamins Publishing Company, 2020. http://dx.doi.org/10.1075/lllt.54.10byr.
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Bulté, Bram, and Alex Housen. "Chapter 9. A critical appraisal of the CDST approach to investigating linguistic complexity in L2 writing development." In Complex Dynamic Systems Theory and L2 Writing Development, 207–38. Amsterdam: John Benjamins Publishing Company, 2020. http://dx.doi.org/10.1075/lllt.54.09bul.
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Larsen-Freeman, Diane. "Complex Dynamic Systems Theory." In Theories in Second Language Acquisition, 248–70. Third edition. | New York, NY: Routledge, 2020. | Series: Second language acquisition research: Routledge, 2020. http://dx.doi.org/10.4324/9780429503986-11.
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Friesz, Terry L., and David Bernstein. "Elements of Graph Theory." In Complex Networks and Dynamic Systems, 75–120. Boston, MA: Springer US, 2016. http://dx.doi.org/10.1007/978-1-4899-7594-2_3.
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Ruscoe, Gordon C. "Complex Organizations and Living Systems Theory." In Analysis of Dynamic Psychological Systems, 181–94. Boston, MA: Springer US, 1992. http://dx.doi.org/10.1007/978-1-4615-6440-9_7.
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Ushioda, Ema. "6. Context and Complex Dynamic Systems Theory." In Motivational Dynamics in Language Learning, edited by Zoltán Dörnyei, Peter D. MacIntyre, and Alastair Henry, 47–54. Bristol, Blue Ridge Summit: Multilingual Matters, 2014. http://dx.doi.org/10.21832/9781783092574-008.
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Verspoor, Marjolijn, and Wander Lowie. "Complex Dynamic Systems Theory and Second Language Development." In Research Questions in Language Education and Applied Linguistics, 799–803. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-79143-8_138.
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Fogal, Gary G. "Chapter 11. Unpacking ‘simplex systems’." In Complex Dynamic Systems Theory and L2 Writing Development, 271–94. Amsterdam: John Benjamins Publishing Company, 2020. http://dx.doi.org/10.1075/lllt.54.11fog.
Full textConference papers on the topic "Complex Dynamic Systems Theory (CDST)"
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Butenina, D. V., and V. S. Metrikin. "ON THEORY OF DYNAMIC FRICTIONAL SYSTEMS WITH MEMORY." In Modeling and situational quality management of complex systems. Saint-Petersburg State University of Aerospace Instrumentation, 2020. http://dx.doi.org/10.31799/978-5-8088-1449-3-2020-1-11-19.
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Li, Yuting, and Fuyuan Xiao. "A Complex Dynamic Weight Assignment Method for Conflict Management in Complex Evidence Theory." In 2021 IEEE International Conference on Unmanned Systems (ICUS). IEEE, 2021. http://dx.doi.org/10.1109/icus52573.2021.9641460.
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Chandan, Vikas, Gina Zak, and Andrew Alleyne. "Modeling of Complex Hydronic Systems for Energy Efficient Operation." In ASME 2009 Dynamic Systems and Control Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/dscc2009-2558.
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Energy requirements for heating and cooling of residential, commercial and industrial spaces constitute a major fraction of end use energy consumed. Centralized systems such as hydronic networks are becoming increasingly popular to meet those requirements. Energy efficient operation of such systems requires intelligent energy management strategies, which necessitates an understanding of the complex dynamical interactions among its components from a mathematical and physical perspective. In this work, concepts from linear graph theory are applied to model complex hydronic networks. Further, time-scale decomposition techniques have been employed to obtain a more succinct representation of the overall system dynamics. Lastly, the usefulness of the proposed model for energy efficient operation of the system through advanced control techniques has been discussed.
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Zhang, Ling. "Personalizing Learning Through the Lenses of Complex Dynamic Systems Theory and Universal Design for Learning." In 2020 AERA Annual Meeting. Washington DC: AERA, 2020. http://dx.doi.org/10.3102/1576869.
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Wu, Gao. "Dynamic Blurry Evaluation Model of Complex Risk of the Super-huge Engineering Project Based on Game Theory." In 2014 Fifth International Conference on Intelligent Systems Design and Engineering Applications (ISDEA). IEEE, 2014. http://dx.doi.org/10.1109/isdea.2014.104.
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Mi, Jinhua, Yan-Feng Li, Weiwen Peng, Yuan-Jian Yang, and Hong-Zhong Huang. "Service-Life Assessment of Complex Dynamic Systems Under Interval Uncertainty Based on Bayesian Networks." In ASME 2015 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/detc2015-47113.
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Service-life is a widely used reliability index in reliability engineering. For a complex dynamic system for which whole system tests are limited, and there is insufficient information to determine the distribution function of reliability models. Fortunately, the boundaries of lifetime variable can be obtained, which can be incorporated through the theory of interval uncertainty. In this study, a service-life assessment method for complex dynamic systems under interval uncertainty is introduced based on Bayesian networks (BN). Firstly, a dynamic fault tree (DFT) model is built for a system. Based on the comprehensive integration of test data, field data, design data and engineering experience, the lifetime of system units are expressed as interval numbers. Then, a coefficient of variation (COV) method is employed to determine the parameters of life distributions. Finally, the BN method is used to estimate the mean life of the example system, and the service-life of this system is assessed as well. The presented method can be easily used in engineering practice for service-life evaluation of complex dynamic systems under interval uncertainty, where lifetime data is limited.
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Vadali, Madhu, Zhijie Sun, Yuzhen Xue, and Jason Dykstra. "Dynamic Modeling of Bottomhole Assembly." In ASME 2014 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/dscc2014-5927.
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This paper presents a comprehensive 4D dynamic model of a bottomhole assembly (BHA) used for directional drilling of oil and gas wells. Although directional drilling has been in practice for some time, it still poses several challenges, particularly related to building an autonomous drilling system. The difficulty with drilling automation derives from the complexity of the process that includes interaction with the borehole and fluid (mud) flow and complex downhole vibrations, such as bit-bounce (axial), whirl (lateral), and stick/slip (torsional). Moreover, the measurements from a limited number of downhole sensors are usually contaminated with high noise levels, and can only be transmitted at low rates with long transmission delays using mud pulsing, or at a high cost using wired pipe. Therefore, it is preferable that the directional drilling system work autonomously with limited communication to the surface. To facilitate this, a compressive physics-based model of the BHA behavior was created to be used in control system development. In this work, the 4D dynamic model of the BHA accounts for the dynamics in rotation, axial motion, and bending along two lateral directions. The model uses a lumped mass-spring system and the system parameters (mass and stiffness) are derived from the shear beam theory of a flexible beam under certain boundary conditions. Simulation results of the model were successful in qualitatively replicating the three types of downhole vibrations, namely bit-bounce, whirl, and stick/slip, and are discussed in this paper. The model is shown to qualitatively replicate downhole conditions and can be implemented in real-time, thereby making it suitable for autonomous directional drilling control.
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Lee, Kok-Meng, Wayne Daley, and Tom McKlin. "An Interactive Learning Tool for Dynamic Systems and Control." In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-0235.
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Abstract Although there are many stimulating and practical applications for system dynamics and automatic control, students often find the material too abstract, too mathematical, and difficult to master when it is presented in lectures. The difficulties experienced by students in learning system dynamics and controls include the following: (1) Dynamic and control systems are interdisclipinary in nature and require complex mathematical expressions that were taught in previous courses. (2) Computer simulation and hands-on experiments are necessary in order for the students to fully appreciate the basic concepts of automatic control. (3) Lecture hours are insufficient to provide both the theory and real-world applications of system modeling and automatic control. In order to overcome these problems, an interactive multimedia software tool that allows the students to explore the design space was developed. We discuss here the role of technology as it can be applied in teaching system dynamics and control. The primary goal of this work is to build a tool that assists students in learning system dynamics and control by providing a link between control system design (CSD) theory and laboratory learning. Specifically, the materials developed provide support in three different forms of instruction; labs, lectures and homework.
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Gilmore, B. J., and R. J. Cipra. "Simulation of Planar Dynamic Mechanical Systems With Changing Topologies: Part II — Implementation Strategy and Simulation Results for Example Dynamic Systems." In ASME 1987 Design Technology Conferences. American Society of Mechanical Engineers, 1987. http://dx.doi.org/10.1115/detc1987-0103.
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Abstract Part II presents a technique which uses the general point to line kinematic constraint equation presented in Part I coupled with an incidence matrix to automatically formulate the kinematic constraint equations between contacting rigid bodies and solve the resulting dynamic equations of motion. The automatic determination of system connectivity coupled with impulse-momentum theory enables the strategy to handle impact between rigid bodies in line contact or between rigid bodies in topologically complex systems. The characterizations of the changes in the kinematic constraints, as described by Part I, are combined with the incidence matrix and impact analysis to form an automatic dynamic simulation strategy. The strategy automatically predicts, detects, and determines the changes in the system topology and then reformulates the equations of motion without the user specifying the kinematic constraint changes and resulting system topology. The simulation results of two example systems are presented. The examples illustrate the effect the boundaries have on a system’s motion and show that the only connectivity data required by the strategy is the initial system topology.
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Annaswamy, A. M., C. Thanomsat, N. R. Mehta, and A. P. Loh. "A New Approach to Estimation of Nonlinear Parametrization in Dynamic Systems." In ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0398.
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Abstract Nonlinear parametrizations occur in dynamic models of several complex engineering problems. The theory of adaptive estimation and control has been applicable, by and large, to problems where parameters appear linearly. We have recently developed an adaptive controller that is capable of estimating parameters that appear nonlinearly in dynamic systems in a stable manner. In this paper, we present this algorithm and its applicability to the problem of temperature regulation in chemical reactors. It is shown in that the proposed controller leads to a significantly better performance than those based on linear parametrizations.
Reports on the topic "Complex Dynamic Systems Theory (CDST)"
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Perdigão, Rui A. P., Carlos A. L. Pires, and Julia Hall. Synergistic Dynamic Theory of Complex Coevolutionary Systems: Disentangling Nonlinear Spatiotemporal Controls on Precipitation. Meteoceanics, November 2016. http://dx.doi.org/10.46337/161110.
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Соловйов, Володимир Миколайович, Наталя Володимирівна Моісеєнко, and Олена Юріївна Тарасова. Complexity theory and dynamic characteristics of cognitive processes. Springer, January 2020. http://dx.doi.org/10.31812/123456789/4143.
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The features of modeling of the cognitive component of social and humanitarian systems have been considered. An example of using entropy multiscale, multifractal, recurrence and network complexity measures has shown that these and other synergetic models and methods allow us to correctly describe the quantitative differences of cognitive systems. The cognitive process is proposed to be regarded as a separate implementation of an individual cognitive trajectory, which can be represented as a time series and to investigate its static and dynamic features by the methods of complexity theory. Prognostic possibilities of the complex systems theory will allow to correct the corresponding pedagogical technologies. It has been proposed to track and quantitatively describe the cognitive trajectory using specially transformed computer games which can be used to test the processual characteristics of thinking.
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Nechaev, V., Володимир Миколайович Соловйов, and A. Nagibas. Complex economic systems structural organization modelling. Politecnico di Torino, 2006. http://dx.doi.org/10.31812/0564/1118.
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One of the well-known results of the theory of management is the fact, that multi-stage hierarchical organization of management is unstable. Hence, the ideas expressed in a number of works by Don Tapscott on advantages of network organization of businesses over vertically integrated ones is clear. While studying the basic tendencies of business organization in the conditions of globalization, computerization and internetization of the society and the results of the financial activities of the well-known companies, the authors arrive at the conclusion, that such companies, as IBM, Boeing, Mercedes-Benz and some others companies have not been engaged in their traditional business for a long time. Their partner networks performs this function instead of them. The companies themselves perform the function of system integrators. The Tapscott’s idea finds its confirmation within the framework of a new powerful direction of the development of the modern interdisciplinary science – the theory of the complex networks (CN) [2]. CN-s are multifractal objects, the loss of multifractality being the indicator of the system transition from more complex state into more simple state. We tested the multifractal properties of the data using the wavelet transform modulus maxima approach in order to analyze scaling properties of our company. Comparative analysis of the singularity spectrumf(®), namely, the difference between maximum and minimum values of ® (∆ = ®max ¡ ®min) shows that IBM company is considerably more fractal in comparison with Apple Computer. Really, for it the value of ∆ is equal to 0.3, while for the vertically integrated company Apple it only makes 0.06 – 5 times less. The comparison of other companies shows that this dependence is of general character. Taking into consideration the fact that network organization of business has become dominant in the last 5-10 years, we carried out research for the selected companies in the earliest possible period of time which was determined by the availability of data in the Internet, or by historically later beginning of stock trade of computer companies. A singularity spectrum of the first group of companies turned out to be considerably narrower, or shifted toward the smaller values of ® in the pre-network period. The latter means that dynamic series were antipersistant. That is, these companies‘ management was rigidly controlled while the impact of market mechanisms was minimized. In the second group of companies if even the situation did changed it did not change for the better. In addition, we discuss applications to the construction of portfolios of stock that have a stable ratio of risk to return.
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Soloviev, Vladimir, Natalia Moiseienko, and Olena Tarasova. Modeling of cognitive process using complexity theory methods. [б. в.], 2019. http://dx.doi.org/10.31812/123456789/3609.
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The features of modeling of the cognitive component of social and humanitarian systems have been considered. An example of using multiscale, multifractal and network complexity measures has shown that these and other synergetic models and methods allow us to correctly describe the quantitative differences of cognitive systems. The cognitive process is proposed to be regarded as a separate implementation of an individual cognitive trajectory, which can be represented as a time series and to investigate its static and dynamic features by the methods of complexity theory. Prognostic possibilities of the complex systems theory will allow to correct the corresponding pedagogical technologies.
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Соловйов, В. М., and О. С. Лук’янчук. Фолксономія соціально-економічних об’єктів в складних мережах засобами CorrRank. Брама-Україна, 2014. http://dx.doi.org/10.31812/0564/1307.
Full textAbstract:
The financial and economic crisis 2007-2009 shown that economic institutions are closely linked and the behavior of complex systems is difficult predictable. There is an urgent need to develop new quantitative methods that adequately describe the dynamic changes in complex systems during normal conditions and during the crisis. There is a need for methods that describe the topology of the interaction between economic institutions, using the tools developed in the theory of networks. The paper used a method of investigation of nonlinear dynamics, as the random matrices theory, which when combined with network methods are adequate means for the study of complex systems. The given technique we have implemented the study in the real time series of global stock markets.
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Soloviev, Vladimir, and Andrey Belinskij. Methods of nonlinear dynamics and the construction of cryptocurrency crisis phenomena precursors. [б. в.], 2018. http://dx.doi.org/10.31812/123456789/2851.
Full textAbstract:
This article demonstrates the possibility of constructing indicators of critical and crisis phenomena in the volatile market of cryptocurrency. For this purpose, the methods of the theory of complex systems such as recurrent analysis of dynamic systems and the calculation of permutation entropy are used. It is shown that it is possible to construct dynamic measures of complexity, both recurrent and entropy, which behave in a proper way during actual pre-crisis periods. This fact is used to build predictors of crisis phenomena on the example of the main five crises recorded in the time series of the key cryptocurrency bitcoin, the effectiveness of the proposed indicators-precursors of crises has been identified.
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Shmulevich, Itzhak, Shrini Upadhyaya, Dror Rubinstein, Zvika Asaf, and Jeffrey P. Mitchell. Developing Simulation Tool for the Prediction of Cohesive Behavior Agricultural Materials Using Discrete Element Modeling. United States Department of Agriculture, October 2011. http://dx.doi.org/10.32747/2011.7697108.bard.
Full textAbstract:
The underlying similarity between soils, grains, fertilizers, concentrated animal feed, pellets, and mixtures is that they are all granular materials used in agriculture. Modeling such materials is a complex process due to the spatial variability of such media, the origin of the material (natural or biological), the nonlinearity of these materials, the contact phenomenon and flow that occur at the interface zone and between these granular materials, as well as the dynamic effect of the interaction process. The lack of a tool for studying such materials has limited the understanding of the phenomena relevant to them, which in turn has led to energy loss and poor quality products. The objective of this study was to develop a reliable prediction simulation tool for cohesive agricultural particle materials using Discrete Element Modeling (DEM). The specific objectives of this study were (1) to develop and verify a 3D cohesionless agricultural soil-tillage tool interaction model that enables the prediction of displacement and flow in the soil media, as well as forces acting on various tillage tools, using the discrete element method; (2) to develop a micro model for the DEM formulation by creating a cohesive contact model based on liquid bridge forces for various agriculture materials; (3) to extend the model to include both plastic and cohesive behavior of various materials, such as grain and soil structures (e.g., compaction level), textures (e.g., clay, loam, several grains), and moisture contents; (4) to develop a method to obtain the parameters for the cohesion contact model to represent specific materials. A DEM model was developed that can represent both plastic and cohesive behavior of soil. Soil cohesive behavior was achieved by considering tensile force between elements. The developed DEM model well represented the effect of wedge shape on soil behavior and reaction force. Laboratory test results showed that wedge penetration resistance in highly compacted soil was two times greater than that in low compacted soil, whereas DEM simulation with parameters obtained from the test of low compacted soil could not simply be extended to that of high compacted soil. The modified model took into account soil failure strength that could be changed with soil compaction. A three dimensional representation composed of normal displacement, shear failure strength and tensile failure strength was proposed to design mechanical properties between elements. The model based on the liquid bridge theory. An inter particle tension force measurement tool was developed and calibrated A comprehensive study of the parameters of the contact model for the DEM taking into account the cohesive/water-bridge was performed on various agricultural grains using this measurement tool. The modified DEM model was compared and validated against the test results. With the newly developed model and procedure for determination of DEM parameters, we could reproduce the high compacted soil behavior and reaction forces both qualitatively and quantitatively for the soil conditions and wedge shapes used in this study. Moreover, the effect of wedge shape on soil behavior and reaction force was well represented with the same parameters. During the research we made use of the commercial PFC3D to analyze soil tillage implements. An investigation was made of three different head drillers. A comparison of three commonly used soil tillage systems was completed, such as moldboard plow, disc plow and chisel plow. It can be concluded that the soil condition after plowing by the specific implement can be predicted by the DEM model. The chisel plow is the most economic tool for increasing soil porosity. The moldboard is the best tool for soil manipulation. It can be concluded that the discrete element simulation can be used as a reliable engineering tool for soil-implement interaction quantitatively and qualitatively.