Dissertations / Theses: 'Behavioural dynamics'

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Yusuf, Afees Olanrewaju. "Behavioural aspects of self-employment dynamics." Thesis, Kingston University, 2014. http://eprints.kingston.ac.uk/29883/.

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Using data from the British Household Panel Survey, the thesis provides both empirical evidence and theoretical explanations to show the nature, behaviour, and roles of job satisfaction and personality on self-employed entrepreneurship survival. The thesis poses three research questions: Does self-employed job satisfaction adapt? Does job satisfaction predict the likelihood of survival of self-employed businesses after start-ups? Does personality play a role in the survival probability of men and women who manage self-employed enterprises? The first question hypothesises that the initial boost in job satisfaction associated with the transition into self-employment is transitory, dissipating rapidly during the early years of the self-employment venture. Findings suggest that men who become self-employed enjoy a more permanent boost in overall job satisfaction, satisfaction with pay and, to some extent, satisfaction with the nature of the work itself. Women experience a boost in satisfaction with the nature of the work itself and to, a lesser extent, a boost in satisfaction with pay. Both of these effects for women are short-lived, casting doubt on the importance of job satisfaction, work-schedule flexibility, and work-life balance as pull factors into self-employment. The second question re-examines the link between job satisfaction and self-employment survival and argues that the relationship is not necessarily a contemporaneous one. That is, job satisfaction at time t is not necessarily the best predictor of survival/exit at time t, but it is the whole self-employment experience that matters rather than the last reported satisfaction. The results show that job satisfaction does not predict the probability of survival. Rather, the maximum job satisfaction and the peak-end combinations during the self-employment episode are better predictors of survival. The last question draws on the robust measures of personality to forecast the survival chances of men and women-managed enterprises, paying attention to occupational differences. Findings show that, unlike previous studies, different personality traits predict men and women-managed ventures survival chances over time; and that the likelihood of survival overtime of both men and women-managed enterprises by occupational categories is dependent on the different personality traits complementing themselves in different scenarios. The thesis contributes to the existing literature by offering a novel behavioural research perspective into the analysis of self-employment dynamics.

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Bouvet, Cécile. "Auditory-motor entrainment : behavioural and cerebral dynamics." Thesis, Montpellier, 2020. http://www.theses.fr/2020MONT4002.

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Nous synchronisons nos mouvements avec les rythmes auditifs présents dans notre environnement sans même en avoir l’intention. Cette coordination, qui influence la stabilité du mouvement produit, s’est avéré bénéfique dans des contextes sportifs et thérapeutiques. À ce jour, la recherche a atteint un large consensus sur les mécanismes sous-tendant les processus de coordination sensori-motrice intentionnelle, mais explore toujours les mécanismes d’entraînement audio-moteur spontanés. Cette thèse aborde la dynamique de synchronisation non-intentionnelle pour différentes relations de fréquence entre un mouvement périodique et un rythme auditif. À travers quatre études complémentaires, ce travail questionne le rôle de multiples niveaux de graduation temporelle et de leur accentuation dans l’émergence et la stabilité de formes simples vs. complexes de synchronisation. La 1ère étude confirme quantitativement l’émergence d’une synchronisation audio-motrice spontanée, différente d’une relation de fréquence de 1:1. La 2ème étude introduit le bénéfice de l’addition d’un patron d’accentuation congruent pour l’émergence de synchronisation à différents rapports de fréquence. Elle permet également d’observer qu’un patron d’accentuation ternaire est plus favorable à la synchronisation qu’un patron d’accentuation binaire. La 3ème étude s’intéresse à cette découverte via l’enregistrement Électroencéphalographique des réponses neurales aux différents patrons d’accentuation, confirmant une différence de réponse aux stimulations binaires et ternaires, liée aux performances comportementales. La 4ème étude se concentre sur le bénéfice des patrons d’accentuation sur la production de mouvement plus complexe. Elle considère également les réponses neurales aux différents patrons d’accentuation en prenant en compte la congruence avec la coordination motrice produite, démontrant l’influence des systèmes sensoriels et moteur sur la perception rythmique. En résumé, ces résultats démontrent qu’un entraînement audio-moteur spontané peut émerger à différents ratios de fréquences en conformité avec les prédictions de l’approche des systèmes dynamiques de l’action et de la perception. De plus, l’entraînement audio-moteur spontané est modulé (i.e., promu ou dégradé) par l’addition de patrons d’accentuation, selon leur congruence avec le mode de fréquence audio-moteur et les réponses neurales. D’autre part, des formes plus complexes de coordination répondent de façon similaire à la présence d’accentuation, soutenues par le couplage audio-moteur et les processus de perception rythmique auditive. Ainsi, les conclusions de cette thèse ouvrent de nouvelles pistes de recherche sur la synchronisation audio-motrice spontanée et son application à l’entraînement et la réhabilitation des performances motrices
We often synchronise our movements to auditory rhythms in our environment without the intention to do so. Such coordination influences the stability of movement performance, and, therefore, can be used to our benefit in sport and therapeutic contexts. Research to date has largely reached a consensus about the mechanisms underlying intentional sensory-motor coordination, but spontaneous auditory-motor entrainment is still under exploration. This thesis addresses the dynamics of unintentional synchronisation towards various frequency relationships between periodic movement and auditory rhythm frequencies. It presents four complementary studies questioning the role of multiple metrical levels and their accentuation on the emergence and stability of simple vs. complex synchronisation in healthy adults. The 1st study confirms quantitatively the emergence of spontaneous synchronisation at frequency ratios different from 1:1. The 2nd study introduces the benefit of a congruent accentuation pattern on the emergence of various frequency ratios. It leads to the observation that a ternary accentuation pattern facilitates synchronisation more than a binary accentuation pattern. The 3rd study examines this new finding through the recording of neural responses to various accented patterns using Electroencephalography, confirming a differential response to ternary and binary patterns linked to behavioural performance. The 4th study focuses on the benefit of accentuation patterns for the production of a more complex type of movement coordination. It also measured neural tracking of the accentuation pattern relative to the congruence of the motor coordination performed, showing that both sensory and motor systems influenced rhythm perception. All together, these results demonstrate that spontaneous auditory-motor entrainment can emerge at various frequency ratios in accordance with the predictions of the dynamical systems approach to action and perception. Furthermore, spontaneous auditory-motor entrainment is modulated (i.e., increased or decreased) by the addition of simple accentuation patterns, depending on congruence with the auditory-motor frequency mode and the neural response to the accents. In addition, more complex multi-limb motor coordination performance responds similarly to accentuation, underpinned by auditory-motor coupling and sensory processing of the auditory rhythms. Therefore, the findings of this thesis open new avenues for future research on spontaneous auditory-motor coordination and its application in the training and rehabilitation of motor performance

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Borragan, Pedraz Guillermo. "Behavioural bases and functional dynamics of cognitive fatigue." Doctoral thesis, Universite Libre de Bruxelles, 2016. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/237311.

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La fatigue cognitive représente un phénomène auquel nous sommes tous familiers. Nous en faisons quotidiennement l'expérience, celle-ci étant associée à une réduction de productivité, une augmentation de risques professionnels et une diminution de notre qualité de vie. Malgré l’importance sociétale de ces implications, qui ont fait de l'étude de la fatigue cognitive une de plus investiguées dans le domaine des sciences cognitives, il subsiste un manque de vision commune ainsi qu'une théorie unifiée de la fatigue cognitive, déterminant son origine et ses fonctions, tandis que son caractère stochastique continue à diviser le milieu scientifique. La présente dissertation présente une approche multimodale combinant des données comportementaux et de neuroimagerie spectroscopie proche infrarouge (fNIRS) pour investiguer les facteurs à l’origine du déclenchement du phénomène ainsi que les dynamiques cérébrales associées. Nos résultats suggèrent que la fatigue cognitive ressentie associée à la chute de performance est une fonction de la charge cognitive définie par le Time Based Shared Resources Model (TBRS). Au niveau neural, nous discutons la présence des systèmes de compensation et les changements de connectivité cérébrale dans ce déclenchement. et comment les possibles mécanismes responsables de la maintenance de performance durant des demandes attentionnelles soutenues y sont associées.
Doctorat en Sciences psychologiques et de l'éducation
info:eu-repo/semantics/nonPublished

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Kunc, Martin Horacio. "Dynamics of competitive industries : a micro behavioural framework." Thesis, London Business School (University of London), 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417597.

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Kulich, Martin. "Dynamic Template Adjustment in Continuous Keystroke Dynamics." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2015. http://www.nusl.cz/ntk/nusl-234927.

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Dynamika úhozů kláves je jednou z behaviorálních biometrických charakteristik, kterou je možné použít pro průběžnou autentizaci uživatelů. Vzhledem k tomu, že styl psaní na klávesnici se v čase mění, je potřeba rovněž upravovat biometrickou šablonu. Tímto problémem se dosud, alespoň pokud je autorovi známo, žádná studie nezabývala. Tato diplomová práce se pokouší tuto mezeru zaplnit. S pomocí dat o časování úhozů od 22 dobrovolníků bylo otestováno několik technik klasifikace, zda je možné je upravit na online klasifikátory, zdokonalující se bez učitele. Výrazné zlepšení v rozpoznání útočníka bylo zaznamenáno u jednotřídového statistického klasifikátoru založeného na normované Euklidovské vzdálenosti, v průměru o 23,7 % proti původní verzi bez adaptace, zlepšení však bylo pozorováno u všech testovacích sad. Změna míry rozpoznání správného uživatele se oproti tomu různila, avšak stále zůstávala na přijatelných hodnotách.

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Papiorek, Sarah [Verfasser]. "Behavioural and ecological dynamics in competitive pollination networks / Sarah Papiorek." Düsseldorf : Universitäts- und Landesbibliothek der Heinrich-Heine-Universität Düsseldorf, 2015. http://d-nb.info/1071947109/34.

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Zeng, Chaoshu. "Behavioural basis of larval dynamics in the crab Carcinus maenas." Thesis, Bangor University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296340.

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Mohammadian, Saeed. "Freeway traffic flow dynamics and safety: A behavioural continuum framework." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/227209/1/Saeed_Mohammadian_Thesis.pdf.

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Congestion and rear-end crashes are two undesirable phenomena of freeway traffic flows, which are interrelated and highly affected by human psychological factors. Since congestion is an everyday problem, and crashes are rare events, congestion management and crash risk prevention strategies are often implemented through separate research directions. However, overwhelming evidence has underscored the inter-relation between rear-end crashes and freeway traffic flow dynamics in recent decades. This dissertation develops novel mathematical models for freeway traffic flow dynamics and safety to integrate them into a unifiable framework. The outcomes of this PhD can enable moving towards faster and safer roads.

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Horsfield, Giles Frederick. "Behavioural aspects of the population genetics of the domestic cat." Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284672.

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Nehme, Rabih. "Dynamics of audit quality : behavioural approach and governance framework : UK evidence." Thesis, Durham University, 2013. http://etheses.dur.ac.uk/9385/.

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The research objective is to study and analyse different factors potentially involved in influencing the measuring of auditor behaviour and audit quality that would lead to auditorsꞌ failure. It covers areas related to auditing, accounting, and corporate governance. The first empirical study assesses auditors' behaviour against audit firm factors (time deadline, time budget and performance evaluation). It also explains how behaviour may differ among experienced auditors and audit trainees. The results show that the majority of auditors commit dysfunctional behaviour but they try to avoid it in technical audit areas. The majority of auditors knowingly commit dysfunctional behaviour for the sake of better performance. It is noted that some of dysfunctional behaviour acts are due to a misperception of the concept of dysfunctional behaviour during an audit assignment. Auditors assume they are contributing to the benefit of an audit assignment while in fact they are committing dysfunctional behaviour. The second empirical model is constructed to assess the theoretical and statistical relationship between audit quality and clients' corporate governance characteristics. As for corporate governance mechanisms, the results show that audit quality has a significant positive relationship with board of directors' size and independence and a negative relationship with role duality. It can be concluded that within the British context, a bigger board of directors with diverse backgrounds leads to better audit quality. Also, more independent directors lead to better audit quality. For audit committee variables and their impact on audit quality, the results show that there is no significant statistical relationship between audit committee independence and size and audit quality; but there is a positive significant relationship between audit committee meetings and audit quality. This result gives an indicator that the more active audit committees in British companies, the better audit quality is achieved.

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Wang, Tongya. "Behavioural biases and evolutionary dynamics in an agent-based financial market." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/7911/.

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This research is devoted to the study of financial market dynamics in a framework which combines agent-based modelling and concepts from behavioural finance. The thesis explores, in an agent-based financial market model, the interlinkage between investor heterogeneity, bounded rationality, behavioural biases and the aggregate market dynamics. We develop a dynamic equilibrium model of a financial market in the presence of heterogeneous, boundedly rational investors. The model combines a performance-driven strategy-switching mechanism of an adaptive belief system (Brock and Hommes, 1998) and an evolutionary finance model (Evstigneev, Hens and Schenk-Hopp´e, 2011). A key feature of this new model is that it contains a combination of passive and active learning dynamics. Passive learning refers to the market force by which wealth accumulates on investment strategies which have done relatively well. Active learning refers to the switching behaviour by which investors actively move their wealth into strategies which have performed well in the recent or distant past. This thesis extends the literature by examining the joint effect of passive and active learning in relation to the evolutionary dynamics of financial markets. By drawing in concepts from behavioural finance, we focus on the micro-level modelling of various heuristics and behavioural biases which may affect investors’ active learning and financial forecasting, such as overconfidence, recency bias, sentiment, etc. We quantify the macro-level market impact of these behavioural elements and study the evolutionary prospects of market dynamics. We show that the interaction between passive and active learning is crucial to understanding the market selection of dominant strategy or the survival of different strategies. Investors’ bounded rationality and behavioural biases in active learning and financial forecasting play an important role in shaping the market dynamics. Our findings point to the causes of the persistence of market inefficiencies and a variety of stylised facts of financial market. The added value of drawing together agent-based modelling and behavioural finance on the study of financial markets dynamics is demonstrated.

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Griffiths, D. P. "The dynamics of stimulus representation during filial imprinting : behavioural analysis and modelling." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.599724.

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The aim of this study was to test behavioural predictions made by a neural network model of filial importing formulated by Bateson and Horn (1994), namely those involving the phenomena of generalisation, classification together and reversibility in the context of filial importing. The experiments were designed in such a fashion as to stand on their own in providing insights into these aspects of imprinting whilst allowing model predictions to be tested. The results obtained were interpreted in terms of the model, highlighting accurate predictions and suggesting amendments to the model. An initial series of experiments attempted to eliminate the classification together of two stimuli, a red triangle and a purple circle, that resulted from sequential exposure to those stimuli in close temporal contiguity termed mixed exposure by Honey et al. (1994). The results of these experiments suggested that there was a predisposed preference bias for the purple circle over the red triangle, and that exposure to a jungle flow stimulus after mixed exposure reduced this bias. It was also found that exposure to the novel stimulus reduced the bias for purple circle that was presented in naive chicks. This effect was observed in both a heat-reinforced discrimination between the purple circle and the red triangle and a simple sequential preference test between the stimuli. A second set of experiments examined whether the reversal of preference from one stimulus to another proceeds as the neural net model predicts. The results showed that a trained preference for the red triangle could be overturned by subsequent exposure to the purple circle. It took a greater amount of exposure to the purple circle to reverse the preference for the red triangle than it took to initially establish the preference for the red triangle. Furthermore, the preference for the red triangle did not change significantly after exposure to the purple circle when tested against a novel stimulus, a blue cylinder. Both of these results were consistent with the predictions of the model.

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Nystrand, Magdalena. "Effects of Habitat Quality on Behavioural Decisions and Population Dynamics in the Siberian Jay." Doctoral thesis, Uppsala universitet, Institutionen för ekologi och evolution, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6835.

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The dynamics of natural populations may be influenced by a variety of factors, ranging from feeding interference and territoriality to the risk of predation and climatic effects. The relative influence of these factors may be contingent upon the quality of the habitat in which individuals reside. A factor that can largely affect population dynamics and that often covaries with habitat structure is predation risk. However, the combined effect of habitat and predation risk can vary according to the social context and intrinsic characteristics that affect individual behavioural responses. This thesis investigates the effects of habitat quality at the level of the population and the individual, and examines how it relates to the above factors in Siberian jays (Perisoreus infaustus), a territorial, group-living species in which the main cause of mortality is predation. The results demonstrate a strong effect of habitat on survival, reproduction and behaviour. Mortality was generally higher in open areas and managed forests and reproductive success decreased after forest management. Breeding females were more sensitive to environmental factors than males, possibly because of higher reproductive costs. Estimates of spatial demography suggested that there were more sinks than sources, and that they were located in open, managed forests. Behavioural decisions confirmed that open forests were associated with higher predation risks. However, decisions depended on social context; immigrants took highest risks and were the recipients of most aggression, largely an effect of social subordination. Also, parents provide their offspring with benefits that are withheld from immigrants. As a result, first-year survival was higher in retained offspring. Investigating the effects of multi-scale habitat quality on individual behaviour and population dynamics has generated an increased understanding of the effects of forest management on the dynamics of this population. This approach should facilitate development of an effective conservation management policy for this species.

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Garofalo, Paola. "Study and Analysis of Socio-behavioural Dynamics for Decision Support Systems in Smart Buildings." Doctoral thesis, Università degli studi di Trento, 2019. http://hdl.handle.net/11572/243316.

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This thesis deals with the energy saving in smart building with focus on the impact of the user behaviour on the energy consumption. The problem of human behaviour modelling has been widely studied in the state of the art, but it is still an open problem in the field of smart building since the stochastic nature of the behaviour is difficult to be accurately represented by numerical tools. An interdisciplinary approach is proposed in order to identify the suitable user features from the psychological and social point of view and to integrate such a representation into a DSS for appliance scheduling and energy cost reduction. The proposed method has exploited location-based features of the users in order to represent their habits and needs and to compute the schedules that maximize the user acceptance toward an “energy-aware” behaviour. The obtained results point out a reduction of the peak-to-average ratio higher than 40% also considering the user constraints imposed by their presence into the building.

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Garofalo, Paola. "Study and Analysis of Socio-behavioural Dynamics for Decision Support Systems in Smart Buildings." Doctoral thesis, Università degli studi di Trento, 2019. http://hdl.handle.net/11572/243316.

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This thesis deals with the energy saving in smart building with focus on the impact of the user behaviour on the energy consumption. The problem of human behaviour modelling has been widely studied in the state of the art, but it is still an open problem in the field of smart building since the stochastic nature of the behaviour is difficult to be accurately represented by numerical tools. An interdisciplinary approach is proposed in order to identify the suitable user features from the psychological and social point of view and to integrate such a representation into a DSS for appliance scheduling and energy cost reduction. The proposed method has exploited location-based features of the users in order to represent their habits and needs and to compute the schedules that maximize the user acceptance toward an “energy-aware” behaviour. The obtained results point out a reduction of the peak-to-average ratio higher than 40% also considering the user constraints imposed by their presence into the building.

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GALLIERA, ARIANNA. "Adaptation dynamics in individual and strategic behavior: an experimental analysis." Doctoral thesis, Luiss Guido Carli, 2016. http://hdl.handle.net/11385/201083.

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When we look at the first rounds of an experiment, the large differences and variance among individual performances might be driven by a lack of experience and results tend to overestimate this heterogeneity. An experiment based on many rounds helps participants to adapt and improve decisions, both in strategic and non-strategic games; additionally, some individuals may be unaccustomed to a specific game and need some time to understand properly the task and their best (individual) strategy to apply. This dissertation focuses, in four chapters, on adaptation dynamics and experience in strategic games and individual decision games. In particular, the role of experience through time that helps agents to improve their performances in accordance with their preferences. Game repetition allows agents to fill the gap of experience in specific tasks, improving their performances and individual self-confidence. In this sense this dissertation aims to explore different experimental settings in which individuals, playing repeatedly the same task through the whole experiment, are able to become more sophisticated compared to early performances. Two chapters focus on strategic behavior in a bargaining problem, in particular we compare how participants change their behavior through time. A third chapter focuses on the individual adaptation dynamics in a Hybrid Public Good game, in particular the motivation of participants when contributing to a public good in the role of "leader" or "follower". In this work we distinguish between conditional cooperators and exploiters, which adapt differently to the game. The last chapter, looks at individual decisions and experience effect in gambling games. We focus on a well-known cognitive bias, the almost- winning bias; agents misrepresenting the game are unable to distinguish between situations in which near misses signal ability and those in which no ability is involved.

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Pastra, Aspasia S. "Board of directors' dynamics, board effectiveness and organisational performance : the case of Nordic region." Thesis, Brunel University, 2017. http://bura.brunel.ac.uk/handle/2438/15791.

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The thesis aims to explore the effect of team dynamics on team and organisational outcomes. Dynamics is a broad term that encompasses all the processes and attitudes that exist between team members and influence the direction of team's performance. Trust, conflict and behavioural integration comprise psychological facets of teamwork and are amongst the most common dynamics of a team. The current study aims to shed light on the perceptions of board members about the level of conflict, trust and behavioural integration during board meetings, which comprise the most critical forum of the group. Trust, conflict and behavioural integration are the primary attitudes, behaviors, and cognitions that arise within the board and encompass the core aspects of teamwork. There is a gap in the literature for examining the role of social-psychological processes and interactions between the board members because access to the boardroom is difficult and the researchers are forced to turn their attention on secondary data and proxies for board behaviors. Although that board of directors is an upper echelons group of executives who can ensure the long-term survival of the organisations, there is scarce of research in studying boards from a team perspective. Until today, we have limited knowledge of team processes, such as conflict, both inside the boardrooms and in the context of strategy implementation. The literature review in this thesis is drawn from multiple disciplines, including management, psychology and sociology, which enable us to gain a deep understanding of team's dynamics. The methodology has been based on a positivist approach since the focus is centered around the data collection process and the statistical interpretation of the findings. Primary data was collected from board members in Nordic countries, namely Denmark, Finland, Sweden, Iceland and Norway. The data was collected with the use of survey method and the findings are based on 186 usable responses. The Nordic corporate governance model remains still the less known outside the Nordic region (Thomsen, 2016) but this thesis postulates that valuable lessons can emanate from its study. The study of the Nordic model could give us useful lessons for the roles of the board and the structure of their organisations. The statistical analysis of the model involved: Descriptive Analysis, Exploratory Factor Analysis (EFA), Confirmatory Factory Analysis (CFA) and Structural Equation Modeling (SEM). The results of this thesis provide theoretical and managerial recommendations for achieving superior board performance. The importance of the role of the Behavioural Integration inside the boardroom is underlined as a significant finding of this study. Moreover, the role of Trust in the board context raises some important questions about its priority since there may be other processes or dynamics which present more clear-cut results on board effectiveness. Furthermore, the deleterious effects of conflict have been underlined. It is also underlined that in this competitive era boards should go beyond fiduciary responsibilities to a more strategic role on a broader range of matters With the exception of a few studies, researchers still to move inside the "black box" of the upper echelons processes and understand how the executives in the board interact. Building a strong board of directors requires a focus beyond demographic characteristics to board interactions. The most effective boards have the strongest board dynamics and are characterized by openness, teamness and collaborative behaviour. The power of the board comes from the ability of the directors to effectively work together and hopefully the current study contributes substantially to the corporate governance field and the way that team processes affect team outcomes.

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Jones, Theresa. "Social Network Dynamics and Information Transmission in Wild Black-capped Chickadees (Poecile atricapillus)." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34974.

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Animals exhibit a wide variety of social behaviours that are shaped by the external group social structure. Thus, understanding social behaviours and processes requires examining the individual social associations that form the basis of a group’s social network. The first objective of this thesis was to assess the consistency of social position within wild networks of black-capped chickadees (Poecile atricapillus) and to evaluate the effects of individual behavioural traits (exploratory personality and social dominance) on network position. Intra-annual social position was found to be repeatable and centrality increased with dominance rank, suggesting that dominant individuals occupy more central positions. The second objective of this thesis was to evaluate how network position and individual traits influence the transmission of social information through groups; the use of information acquired by other group members is expected to be an important benefit to group living. Social information regarding the location of novel foraging patches was observed to be transmitted through all eight chickadee groups. The rate of information transmission was found to be positively associated with dominance rank, but was not influenced by exploratory personality, indicating that dominant individuals may have greater access to social information than more subordinate individuals. The final aim of this thesis was to assess if social information transmission varied between urban and rural environments, as increased resource variability in more rural sites was expected to lead to higher reliance on social foraging cues. However, no effect of level of urbanisation was detected on the transmission of social information regarding novel food sources, which may indicate a habitat-independent strategy of social information use in chickadees. In general the results from this thesis indicate the importance of dominance status on individuals’ position within a social group, which can lead to differential exposure to social processes, such as social information transmission.

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Decroix, Jérémy. "Dynamics of processing of visual kinematics and goal-related information during the recognition of object directed actions : behavioural and neurophysiological evidence." Thesis, Lille 3, 2020. https://pepite-depot.univ-lille.fr/RESTREINT/EDSHS/2020/2020LIL3H005.pdf.

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Les actions sont des mouvements complexes dirigés vers un but. En dépit du fait que ces buts ne soient pas directement visibles, nous parvenons, en tant qu’observateur, à les identifier et à les anticiper avec succès. Dans cette thèse, nous avons identifié deux approches pour expliquer comment, en tant qu’observateur, nous parvenons à reconnaitre les actions d’autrui. Les approches sensorimotrices considèrent la reconnaissance des actions d’autrui comme une propagation ascendante de la perception des gestes à la reconnaissance des buts. Les gestes sont vus ici comme la principale source d’information à partir de laquelle le but de l’acteur peut être extrait. A l’opposé, les approches prédictives considèrent que l’observateur ne peut pas comprendre les gestes de l’autre sans préalablement prédire son but probable. L’observateur doit donc extraire le but probable de l’action à partir d’autres sources d’information pour le guider dans son traitement des gestes observés. Les connaissances sur le traitement dynamique des gestes observés d’une part et des informations sur le but d’autre part sont critiques pour dissocier ces deux approches et pour permettre une meilleure compréhension des mécanismes qui sous-tendent la reconnaissance des actions d’autrui. Néanmoins, les données empiriques dans cette direction manquent cruellement. Afin de combler cette lacune, nous nous sommes intéressés à la priorité donnée aux gestes observés relativement à celle donnée aux informations sur le but lors de la reconnaissance des actions d’autrui. La contribution des informations sur le geste observé et sur le but a été évaluée indépendamment grâce à l’introduction de violation de geste et/ou de but dans des photographies d’actions dirigées vers des objets. Grâce à des méthodes comportementales (amorçage et tâche de recherche visuelle), nous avons constaté que les informations liées au but sont priorisées durant les premiers stades du traitement visuel des actions, alors que les informations liées aux gestes observés sont priorisées durant les derniers stades du traitement visuel des actions. Grâce à des méthodes neurophysiologiques (potentiels évoqués et stimulation magnétique transcrânienne), nous avons observé que si les deux types d’information sont décodées dès les stades perceptifs du traitement des actions, c’est le traitement informations sur le but (et non sur le geste) qui guide les étapes sémantiques du traitement des actions. Nous apportons par ailleurs des arguments justifiant de l’implication critique du réseau fronto-pariétal dans l’intégration des deux sources d’information. Enfin, nous montrons que la tendance à donner plus d’importance aux informations sur le but relativement à celles sur les gestes observés dépend de caractéristiques individuelles. Dans l’ensemble, les données rapportées ici sont en accord avec les approches prédictives de la reconnaissance des actions. Ces résultats sont discutés à la lumière d’un faisceau d’arguments qui suggèrent que les gestes observés sont utilisés pour mettre à jours des prédictions sur le but de l’acteur, elles-mêmes préalablement dérivées d’autres sources d’informations. Nos données nous amènent finalement à envisager une approche pluraliste de la reconnaissance des actions observées, avec un ensemble de stratégies dont l’usage varie en fonction des situations et des individus
Actions are complex, goal-directed, movements, and despite being hidden in the actor’s mind, observers successfully identify and anticipate actor’s goal. In this thesis, we identified two main approaches to explain how observers recognise others’ actions. Sensorimotor approaches consider action recognition as bottom-up propagation from the perception of visual kinematics to the recognition of action goals. Visual kinematics are viewed here as the primary source of visual information from which goal-related information is extracted. In contrast, predictive approaches assume that observers cannot make sense of visual kinematics without a prediction about the actor’s goal. Observers would extract goal-related information from non-motor sources of information to guide the processing of the visual kinematics. Information about the temporal dynamics of activation of visual kinematics and goal-related information during action visual processing is critical to disentangle the two approaches and to provide a better understanding of the mechanisms underlying action recognition, but empirical data in this direction are clearly lacking. In order to fill this gap, we investigated the relative priority given to visual kinematics versus non-motor goal-related information during the recognition of others’ actions. The contribution of visual kinematics and non-motor goal-related information was independently evaluated by introducing violations of grip and/or visual goal in photographs of object-directed actions. Using behavioural methods (priming and visual-search paradigms), we demonstrated that non-motor goal-related information was prioritised over visual kinematics during the first steps of visual action processing, whereas visual kinematics were prioritised over goal-related information later during visual action processing. Using neurophysiological methods (event-related potential and transcranial magnetic stimulation priming paradigms), we found that both visual kinematics and non-motor goal-related information are already processed during the perceptual stages of action processing, but that action semantic processing is guided by goal-related information rather than visual kinematics. We further provide evidence supporting the critical involvement of the frontoparietal network in the later integration of visual kinematics and non-motor goal-related information. We finally showed that the priority given to non-motor goal-related information over visual kinematics during action visual processing depends on individual social characteristics. Together, the findings reported are consistent with predictive approaches of action recognition. Results are discussed in the light of converging evidence suggesting that visual kinematics are used to update goal predictions that have been previously derived from non-motor goal-related information. Yet findings further orient towards a pluralist view of action understanding, in which the strategies used to process others’ actions may vary depending on situations and individuals

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Petrynych, V. V. "Dynamics of changes of behavioural reactions in sexually mature rats in case of manganese intoxication, depending on the speed of acetylation type." Thesis, БДМУ, 2021. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/19108.

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Sbizera, Martinez Aline. "Reevaluating the dynamics of intertidal rocky shores: The foraging and behavioural ecology of an understudied grazer and its effects on benthic assemblages." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/15485.

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The strongest grazing effect among all marine benthic systems is on intertidal rocky shores. Among intertidal grazers, limpets are well-known structuring agents altering the distribution of rocky shore assemblages. Globally, there are other abundant herbivores whose ecological importance in the dynamics of rocky shores is poorly studied as is the case for herbivorous starfish. Parvulastra exigua is a small starfish that occurs at great densities in rock pools on intertidal shores. This research aimed to understand the behavioural ecology of P. exigua by investigating the feeding and foraging habits of the starfish, competitive interactions between P. exigua and limpets, and the consequent effects on algal assemblages. Parvulastra exigua showed a narrow diet breadth with selection for microalgal food. This species fed during all periods of the tidal cycle. During immersion, the starfish foraged within and around rock pools and only foraged in pools whilst the tide was out. The starfish foraged near their rock pools, potentially creating a halo effect due to localized grazing. Rock pool fidelity in P. exigua varied among locations suggesting that the impact of this starfish on algal assemblages might be contingent on the availability of refugia at low tide and that the extent of the halo effect by P. exigua will vary from place to place. Parvulastra exigua revealed to be an equal competitor to a key limpet on the shore and the starfish was as efficient in controlling macroalgal growth as the limpet, with the strongest effect inside rock pools. These findings demonstrate that P. exigua is an important grazer in intertidal rocky shores. Herbivorous starfish occur on other rocky shores around the world and in sand flats, seagrass and kelp forests. Thus, future work is relevant to examine the effects of starfish herbivory on other shores and ecosystems.

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Miller, Andrew. "Successful interventions with difficult pupil behaviour in primary schools : a critique of consultative practice between educational psychologists and teachers from the perspective of applied behavioural analysis, organisational dynamics and attribution shift." Thesis, University of Sheffield, 1994. http://etheses.whiterose.ac.uk/3477/.

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This two-part study examines practice by educational psychologists who draw upon behavioural psychology when consulting with teachers of pupils of primary age range deemed to be displaying difficult behaviour. The first section examines the content and effectiveness of strategies and aspects of the consultative relationship by means of a postal questionnaire completed by a sample of 68 educational psychologists from 13 Local Education Authorities. Unlike published accounts of successful interventions, this questionnaire study examines practice with a variety of outcomes. Results show that educational psychologists favour approaches that frequently incorporate contingent teacher praise but that there are few grounds to warrant concerns about the 'dangers of a mindless technology' (Berger 1979) or 'behavioural overkill' (Wheldall 1981). The second section of the study concentrates upon the teachers' perspectives and is based upon a structured interview with 24 primary range teachers in 8 LEAs. The teachers were identified by local educational psychologists as having taken part in consultations concerning the difficult behaviour of a pupil in their class. The sample was also selected so that each had experienced successful outcomes following a recommended intervention that derived to some extent from behavioural psychology. Using a grounded theory approach, these outcomes are shown to be far more closely related to factors such as staff culture, organisational boundaries and inter-personal dynamics than is normally recognised in the literature on behavioural interventions. The study concludes with a formal statement of the emergent grounded theory in respect of successful behavioural consultations in primary schools.

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Vidal, Tomás David. "Empirical analysis of market behaviour: a mesoscopic approach." Doctoral thesis, Universitat Jaume I, 2020. http://hdl.handle.net/10803/669625.

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With this doctoral dissertation, we aim to contribute to the literature in two different ways. On the one hand, using an agent based model, we provide policymakers and investors with new methods that can be used in financial markets to assess their stability, describe their dynamics, and forecast their future performance. On the other hand, we analyse the evolution of the cross-sectional distribution of activity in the real economy to better understand the firms' destiny. The main results of our two first chapters show that models based on the social interactions provide investors with useful information to set trading strategies, while the last chapter of this thesis demonstrates that the firms' destiny can be tracked by means of the analysis of their profit and growth rate cross-sectional distribution over time.

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Rafeld, Hagen [Verfasser], Peter N. [Akademischer Betreuer] Posch, and Christiane [Gutachter] Pott. "Essays on rogue traders and collusive rogue trading: Implications of control balance, organizational misbehaviour, and behavioural patterns of group dynamics / Hagen Rafeld ; Gutachter: Christiane Pott ; Betreuer: Peter N. Posch." Dortmund : Universitätsbibliothek Dortmund, 2018. http://d-nb.info/1179449517/34.

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Izquierdo, Eduardo J. "The dynamics of learning behaviour : a situated, embodied, and dynamical systems approach." Thesis, University of Sussex, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488595.

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Tavoni, Alessandro <1977&gt. "Essays on fairness heuristics and environmental dilemmas." Doctoral thesis, Università Ca' Foscari Venezia, 2010. http://hdl.handle.net/10579/1036.

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The issues explored in this work concern individual behaviour and its departure from the rationality paradigm. While different in terms of underlying methodology, the chapters share the unifying theme of fairness as a guiding principle for human behaviour, as well as a focus on its relevance for environmental dilemmas.
Le questioni affrontate nella tesi riguardano i comportamenti individuali e i relativi scostamenti dal paradigma di razionalità. Nonostante l'utilizzo di metodologie diverse nei tre capitoli, essi hanno in comune il tema unificante di equità come principio guida del comportamento umano, così come una particolare attenzione alla sua rilevanza nei dilemmi ambientali.

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Simon, Jean-Marc, Ole-Erich Haas, Signe Kjelstrup, and Ramstad Astrid Lund. "Dynamical behaviour of H 2 molecules on graphite surface: a molecular dynamics study." Diffusion fundamentals 6 (2007) 37, S. 1-2, 2007. https://ul.qucosa.de/id/qucosa%3A14214.

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Andersen, Rachel Joy. "A new model of students' perceptions of the primary school classroom emotional environment : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1017.

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94 items was developed that encapsulate what children notice in their classrooms as affecting the emotional environment and the language they use to describe it. Study 3 had 63 adults use a modified decision task to sort the 94 items into groups of their selection of similarity and dissimilarity. The analysis of these data revealed 11 clusters of items and 3 underlying dimensions - Teacher Affect, Teacher Expectations and Style, and Classroom Dynamics. Each dimension has two opposing ends, and each of the 94 items can be viewed on a three dimensional map showing their relationship to each of the other 93 items along these 3 underlying dimensions. The visual graphic makes these dimensions easy to interpret for those who are likely to be organising classroom environments. This research shows that when given a chance to talk about their experiences in classrooms, students can explain what they value in a classroom, what they will remember about school, and what influences them and their learning.

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Mansfield, Jonathan Mark. "Reaction behaviour from temperature dynamics." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339552.

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Zafeiriou, Lazaros. "Unsupervised analysis of behaviour dynamics." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/45546.

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Human facial behaviour analysis is an important task in developing automatic Human-Computer Interaction systems, having received rapidly increased attention over the past two decades. Dynamics of facial behaviour convey important information (e.g., discriminating posed to spontaneous expressions) and remain up to date a quite unexploited field. This thesis presents machine learning algorithms that focus on solving the relatively unexplored problem of extracting features that can efficiently and effectively capture the temporal dynamics of the behaviour, and can hence be also used for temporal alignment. The proposed methods are all unsupervised, i.e. they do not exploit any label information. The motivation behind the development of unsupervised algorithms lies in the fact that labelled/annotated data are really hard to obtain, since annotating behaviour dynamics is a very time demanding, expensive and labour intensive procedure. Additionally, in these models we incorporate temporal alignment enabling a joint temporal decomposition of two or more time-series into a common expression manifold by employing either low-dimensional sets of landmarks or raw pixel intensities. This is a challenging problem for many scientific disciplines in which the observation samples need to be aligned in time. In particular, this is mainly significant in terms of facial expressions, where the activation of facial muscles (Action Units) typically follows a set of predefined temporal phases. The methods that we propose for capturing the dynamics of facial expressions use Component Analysis (CA) which is a fundamental step in most computer vision applications, especially in terms of reducing the usually high-dimensional input data in a meaningful manner by preserving a certain function. These CA methodologies can be distinguished in deterministic and probabilistic techniques. In deterministic CA, the noise cannot be modelled and these methods they do not provide prior information. On the other hand, probabilistic CA is a very powerful framework that naturally allows the incorporation of noise and a-priori knowledge in the developed models. A significant contribution of our work lies in proposing an Expectation Maximization (EM) algorithm for performing inference in a probabilistic formulation of Slow Feature Analysis (SFA) and extending it in order to handle more than one time varying data sequences. Moreover, we demonstrate that the probabilistic SFA (EM-SFA) algorithm that discovers the common slowest varying latent space of multiple sequences can be combined with Dynamic Time Warping (DTW) techniques for robust sequence time-alignment. Most of the unsupervised learning techniques such as Principal Components Analysis (PCA) enforce only a weak orthogonality constraint, resulting in a very distributed representation that uses cancellations to generate variability. This results to a holistic representation which makes the latent features difficult to be interpreted. For alleviating this, a group of unsupervised learning algorithms known as Non-negative Matrix Factorization (NMF), have been proposed. These algorithms enforce non-negativity constraints resulting to a part-based representation, since they allow only additive and not subtractive combinations. Another major contribution of this thesis lies in proposing a model that combines the properties of temporal slowness and nonnegative parts-based learning into a common framework that aims to learn slow varying parts-based representations of time varying sequences. The proposed representations can be used in order to capture the underlying dynamics of temporal phenomena such as facial behaviour. Furthermore, we extend the above framework in order to align two visual sequences that display the same dynamic phenomenon by proposing a novel joint NMF. The proposed framework enables a joint temporal decomposition of two non-negative time-series into a non-negative shared latent space, where they can be temporally aligned. The proposed method is tailored for the temporal alignment of facial events since it is able to discover the facial parts that are jointly activated in the sequences along with their temporal activation envelope. We demonstrate the power of the proposed decompositions in unsupervised analysis of dynamic visual phenomena, as well as temporal alignment of facial behaviour. The predominant strategy for facial expression analysis and temporal analysis of facial events is the following: a generic facial landmarks tracker, usually trained on thousands of carefully annotated examples, is applied to track the landmark points, and then analysis is performed using mostly the shape and more rarely the facial texture. In this thesis, we challenge the above framework by showing that is feasible to perform joint landmarks localization and temporal analysis of behavioural sequence with the use of a simple face detector and a simple shape model. To this end, we formulate a generative model which jointly describes the data and also captures temporal dependencies by incorporating an autoregressive chain in the latent space. We also extend this model by integrating temporal alignment process in order to align two unsynchronized sequences of observations displaying highly deformable texture-varying objects. The resulting model is the first to perform simultaneous spatial and temporal alignment showing that by treating the problems of deformable spatial and temporal alignment jointly, we achieve better results than considering the problems independent.

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Hussain, Muhammad Imtiaz. "Computational fluid dynamics." Thesis, Aberystwyth University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.257607.

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González, Ignacio. "Dynamic Behaviour of the New Årsta Bridge to Moving Trains : Simplified FE ‐ Analysis and Verifications." Thesis, KTH, Bro- och stålbyggnad (byte av engelskt namn 20110630), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-37019.

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Kilminster, Devin. "Modelling dynamical systems via behaviour criteria." University of Western Australia. Dept. of Mathematics and Statistics, 2002. http://theses.library.uwa.edu.au/adt-WU2003.0029.

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An important part of the study of dynamical systems is the fitting of models to time-series data. That is, given the data, a series of observations taken from a (not fully understood) system of interest, we would like to specify a model, a mathematical system which generates a sequence of “simulated” observations. Our aim is to obtain a “good” model — one that is in agreement with the data. We would like this agreement to be quantitative — not merely qualitative. The major subject of this thesis is the question of what good quantitative agreement means. Most approaches to this question could be described as “predictionist”. In the predictionist approach one builds models by attempting to answer the question, “given that the system is now here, where will it be next?” The quality of the model is judged by the degree to which the states of the model and the original system agree in the near future, conditioned on the present state of the model agreeing with that of the original system. Equivalently, the model is judged on its ability to make good short-term predictions on the original system. The main claim of this thesis is that prediction is often not the most appropriate criterion to apply when fitting models. We show, for example, that one can have models that, while able to make good predictions, have long term (or free-running) behaviour bearing little resemblance to that exhibited in the original time-series. We would hope to be able to use our models for a wide range of purposes other than just prediction — certainly we would like our models to exhibit good free-running behaviour. This thesis advocates a “behaviourist” approach, in which the criterion for a good model is that its long-term behaviour matches that exhibited by the data. We suggest that the behaviourist approach enjoys a certain robustness over the predictionist approaches. We show that good predictors can often be very poorly behaved, and suggest that well behaved models cannot perform too badly at the task of prediction. The thesis begins by comparing the predictionist and behaviourist approaches in the context of a number of simplified model-building problems. It then presents a simple theory for the understanding of the differences between the two approaches. Effective methods for the construction of well-behaved models are presented. Finally, these methods are applied to two real-world problems — modelling of the response of a voltage-clamped squid “giant” axon, and modelling of the “yearly sunspot number”.

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Sieff, Daniela F. "The effects of resource availability on the subsistence strategies of Datoga pastoralists of north west Tanzania." Thesis, University of Oxford, 1995. http://ora.ox.ac.uk/objects/uuid:a499a1dd-3c21-4be9-8572-261a9625b85d.

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Many early anthropological studies treated pastoralist populations as egalitarian, however there is considerable variation in the resources available to individual households. This thesis considers how resources influence the subsistence system of the pastoral Datoga of Lake Eyasi. The two categories of resources considered are wealth and labour. The labour available to Datoga households does not influence the herding strategies of those households. In turn, the herding strategies do not affect the dynamics of cattle herds. This is because households that are short of labour can arrange for their animals to be herded by members of different households, and there are no discernible costs associated with this. Wealth, defined by livestock holdings, can be measured either as total household wealth, or as wealth per capita. These are conceptually distinct. Among the Datoga, households that are wealthy in terms of total livestock holdings, are also wealthy in terms of wealth per capita, but not proportionally more so. Once households have about five livestock units per capita, any increase in household wealth is used to attract new people to the household, rather than to increase the wealth of existing household members. For many aspects of the production system overall household wealth and wealth per capita have a similar effect, but this is not always the case. In some instances overall household wealth can explain variation between households, whereas wealth per capita cannot. This occurs when the absolute number of animals belonging to a household is important. In terms of provisioning the household and household economics, per capita wealth explains more of the variation between households. Overall the Datoga are struggling to survive. They have been alienated from more fertile areas, and consequently they are poor, and herd productivity is low. This is due to the low reproduction rate of cattle, and the high commercial offtake rate of both cattle and small stock. The high commercial offtake rate is driven by subsistence needs and most income is used to buy grain and veterinary products. However, there is considerable variation between households, and compared to poor households, wealthy households have a comparatively low offtake rate of livestock, in terms of both mortality and sales. Consequently, they are managing to retain their livestock holdings, or in a few cases to increase the size of their herds. However, wealthy households are in the minority, and the majority of households are caught in a declining cycle of poverty, and will eventually be forced to drop out of the pastoral system.

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Milton, Daniel J. D. "Dynamic memory allocation within a behavioural synthesis system." Thesis, University of Southampton, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393918.

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Jackson, Andrew Rhys. "Market participant behaviour and equity market dynamics." Thesis, London Business School (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408644.

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Stott, Clifford John T. "The inter-group dynamics of crowd behaviour." Thesis, University of Exeter, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307292.

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Weydahl, Helge. "Dynamic behaviour of fuel cells." Doctoral thesis, Norwegian University of Science and Technology, Department of Materials Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1720.

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This thesis addresses the dynamic behaviour of proton exchange membrane fuel cells (PEMFCs) and alkaline fuel cells (AFCs). For successful implementation in automotive vehicles and other applications with rapidly varying power demands, the dynamic behaviour of the fuel cell is critical. Knowledge of the load variation requirements as well as the response time of the cell at load change is essential for identifying the need for and design of a buffer system.

The transient response of a PEMFC supplied with pure hydrogen and oxygen was investigated by load step measurements assisted by electrochemical impedance spectroscopy and chronoamperometry. Using an in-house designed resistance board, the uncontrolled response in both cell voltage and current upon step changes in a resistive load was observed. The PEMFC was found to respond quickly and reproducibly to load changes. Two transient processes limiting the fuel cell response were identified: i) A cathodic charge transfer process with a potential dependent response time and ii) a diffusion process with a constant response time. The diffusion transient only appeared at high current densities and was offset from the charge transfer transient by a temporarily stable plateau. Transient paths were plotted in the V-i diagram, matching a predicted pattern with overshooting cell voltage and current during a load step.

The transient response of a PEMFC was measured for various cathode gas compositions and gas utilisations (fraction of supplied reactant gas which is consumed in the fuel cell reaction). For a PEMFC operated on pure hydrogen and oxygen, the cell voltage response to current steps was fast, with response times in the range 0.01-1 s, depending on the applied current. For a PEMFC supplied with air as cathode gas, an additional relaxation process related to oxygen transport caused a slower response (appr. 0.1-2 s depending on the applied current). Response curves up to appr. 0.01 s were apparently unaffected by gas composition and utilisation and were most likely dominated by capacitive discharge of the double layer and reaction with surplus oxygen residing in the cathode. The utilisation of hydrogen had only a minor effect on the response curves, while the utilisation of air severely influenced the transient PEMFC response. Results suggested that air flow rates should be high to obtain rapid PEMFC response.

The load-following capability of a single PEMFC was studied by measuring the cell voltage response to a sinusoidal current load with large amplitudes. Effects on the cell voltage response when varying the DC value, amplitude and frequency of the current load were recorded. The load-following capability of the PEMFC was excellent in the operating range where changes in cell voltage were dominated by ohmic losses. No hysteresis in the cell voltage response was observed in this range for frequencies up to 1-10 Hz. In the operating range where changes in cell voltage were dominated by activation losses, hysteresis appeared at lower frequencies (>0.1 Hz) due to sluggish response in the voltage range near open circuit voltage. The increased mass transport limitation imposed when supplying the PEMFC with air caused hysteresis to appear at lower frequencies than for oxygen (above 0.1 Hz, compared to 1-10 Hz for oxygen).

The dynamic behaviour of an AFC supplied with pure oxygen and hydrogen was investigated by load step measurements assisted by electrochemical impedance spectroscopy (EIS). Load step measurements were carried out using an in-house designed resistance board which gave step changes in a purely resistive load. Resistive load steps between various operating points along the polarisation curve were carried out and the corresponding transient response in cell voltage and current was measured. The transient cell response consisted of an initial ohmic drop followed by a relaxation towards the new steady state. The observed response was slower at higher cell voltages. Measured response times varied on a time scale of appr. 10 ms to 10 s, depending on the initial and final voltages. Results from EIS measurements suggested that the potential dependent response time stemmed from the charge transfer reaction at the cathode. Transient response curves were plotted in the V-i diagram and shown to follow a pattern determined by the load resistance and ohmic resistance of the AFC. Results showed that when supplied with pure oxygen and hydrogen, the AFC responded sufficiently fast for automotive applications.

An iso-thermal, one-dimensional, transient model of an AFC cathode was developed, based on mass balances for oxygen and ionic species and floodedagglomerate theory. Model results show the coupled effects of oxygen diffusion, ion transport and propagation of local electrode potential on the response in current density to a cathodic step in electrode potential. For a set of base case parameters, oxygen diffusion and potential propagation, with characteristic time constants of 0.30 and 0.11 ms, respectively, dominated the current response up to appr. 1 ms, while the slower ion diffusion with time constant 5.0 s controlled the final relaxation towards steady state at appr. 60 s. A smaller agglomerate radius and electrode thickness and a smaller double layer capacitance gave faster electrode response. For a cathodic step in electrode potential, an overshoot in faradaic current appeared around 0.5 ms. This overshoot was related to an initially higher oxygen concentration in the agglomerates, but was masked by capacitive current for base case parameters. Simulated response in oxygen concentration profiles suggested that the potential dependent response time found in previous studies can be related to consumption of surplus oxygen in the catalyst layer.

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Shi, Ya-Nan. "Dynamic behaviour of masonry structures." Thesis, University of Bath, 2017. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.715270.

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Masonry structures are especially vulnerable to earthquakes. Previous studies have focused mostly on their mechanical characteristics, while masonry structures vary greatly in terms of structural and material properties. This thesis aims to present the post-crack dynamic behaviour of masonry structures on mechanism. Systematic studies, including pseudo-static experiments, shaking-table experiments and mathematical modelling, were carried out. In the pseudo-static experiments, scaled masonry walls with different geometric forms, bond types and corner connections were tested. The static-phase in-plane and out-of-plane damage mechanisms of masonry walls were classified. Their load factors and the influence of structural configurations were discussed. Experimental load factors are compared with theoretical ones derived from a limit-analysis procedure. The shaking-table experiments successfully captured the dynamic-phase response mechanisms. Three 3D dry masonry models were tested according to sinusoidal excitation based on either constant amplitudes or constant peak accelerations. Conclusions on the dynamic behaviour of the masonry structure were presented. The experimental basis for the theoretical model was presented. The influence of structural configuration and excitation figure were clarified. The critical factors were clarified as being the excitation frequency and L/H ratio of the façade. The consistent damage behaviour variations arising from these two factors were analyzed. A nonlinear dynamic mathematical model for the rocking of the masonry façade was developed, using a two-rigid-body model. The loads and frictional force on the top were included, with a horizontal excitation being applied. Assumptions of rigid ground, inelastic impact and point contact were applied. Six possible patterns were defined. The rocking, the impact and the possible transitions were formulated. Models in the shaking-table experiments were simulated to evaluate this model. Parametric studies were performed and future works were recommended.

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Shi, Yongjiu. "Dynamic behaviour of guyed tower platforms." Thesis, Heriot-Watt University, 1989. http://hdl.handle.net/10399/958.

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Anderson, Gabrielle. "Behavioural properties and dynamic software update for concurrent programmes." Thesis, University of Southampton, 2013. https://eprints.soton.ac.uk/353281/.

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Software maintenance is a major part of the development cycle. The traditional methodology for rolling out an update to existing programs is to shut down the system, modify the binary, and restart the program. Downtime has significant disadvantages. In response to such concerns, researchers and practitioners have investigated how to perform update on running programs whilst maintaining various desired properties. In a multi-threaded setting this is further complicated by the interleaving of different threads' actions. In this thesis we investigate how to prove that safety and liveness are preserved when updating a program. We present two possible approaches; the main intuition behind each of these is to find quiescent points where updates are safe. The first approach requires global synchronisation, and is more generally applicable, but can delay updates indefinitely. The second restricts the class of programs that can be updated, but permits update without global synchronisation, and guarantees application of update. We provide full proofs of all relevant properties.

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Vauclin, Pierre. "Ρerceptiοn et franchissement d'οbstacles dans la lοcοmοtiοn cycliste." Electronic Thesis or Diss., Normandie, 2025. http://www.theses.fr/2025NORMR001.

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L'objectif principal de cette thèse est de valider l'hypothèse générale selon laquelle les cyclistes perçoivent, sélectionnent et actualisent des opportunités d'action (i.e., des affordances) pour franchir des portes, qui sont adaptées à leurs capacités d'action. Lorsqu'un objet est tenu ou attaché au corps, il modifie les dynamiques de contrôle et les capacités d'action d'une manière unique, ce qui implique que les individus doivent être sensibles et calibrés à ce système intégré personne-plus-objet. Cette recherche vise à étendre la théorie des affordances dans le contexte d'un système personne-plus-objet à travers trois expériences de franchissement de porte en cyclisme. Dans une première étude, les résultats ont montré que les cyclistes expérimentés perçoivent des portes plus étroites comme franchissables par rapport aux cyclistes occasionnels, mais que dans les deux cas, cette perception est liée à leurs capacités d'action maximales. Lors d'une deuxième étude, les cyclistes ont été testés pour déterminer si des capacités d'action maximales accrues permettent de prendre des décisions plus précises. Nos résultats ont confirmé que les affordances pour le franchissement de porte sont adaptées aux capacités d'action maximales, mais que, chez les cyclistes intermédiaire, la précision dans la prise de décision diminue à proximité de leurs capacités d'action maximales. Lors d'une troisième étude, il a été étudié si une prise de décision plus précise est associée à un répertoire plus large de modes d'action et à des capacités d'action maximales accrues. Les résultats ont montré que les cyclistes, indépendamment de leurs capacités d'action maximales, exploitent la dégénérescence du système perception-action pour franchir, mais que seule une augmentation des capacités d'action maximales est associée à l'utilisation de modes d'action plus complexes. Cette thèse élargit le champ des affordances pour le franchissement de porte au système personne-plus-objet en démontrant que les individus perçoivent les affordances en relation avec leurs capacités d'action maximales. De plus, les résultats suggèrent qu'une augmentation des capacités d'action maximales en cyclisme est liée à une prise de décision plus précise pour franchir. Cela refléterait une meilleure capacité à intégrer le vélo dans un système intégré personne-plus-objet
The main objective of this thesis is to validate the general hypothesis that cyclists perceive, select and actualize opportunities for action (i.e., affordances) for aperture crossing that are scaled to their action capabilities. Because an object held or attached to the body creates a unique set of actions capabilities and control dynamics, individuals should be attuned and calibrated to this integrated person-plus-object system. It is about extending the theory of affordances in the case of a person-plus-object system through three aperture crossing experiments in cycling. In a first experiment, results showed that experienced cyclists perceive narrower aperture as cross-able than occasional cyclists but that both perceive this affordance in relation to their maximal action capabilities. In a second experiment, cyclists were tested to determine whether greater maximal action capabilities make more accurate decision. Our findings confirmed that affordances for crossing an aperture are scaled to maximal action capabilities, however accuracy in decision-making (i.e. decide to cross or not to cross) decrease near the maximal action capabilities in intermediate cyclists. In a third experiment, it was investigated whether more accurate decision relate to wider repertoire of mode of action and greater maximal action capabilities. Results showed that cyclists, regardless their maximal action capability, would exploit degeneracy of perception-action system to cross apertures but only increasing maximal action capability was associated with the use of more complex action modes. This thesis expend the scope of affordances for aperture crossing to the person-plus-object system by showing that individuals perceive affordances in relation to their maximal action capabilities. Moreover, the findings suggested that increasing maximal action capabilities in cycling is linked to more accurate decision to cross an aperture. This is proposed to reflect an improved ability to incorporate the bike into an integrated person-plus-object system

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Di, Stefano Alessandro. "Evolutionary Dynamics of Social Behaviours on Multilayer Networks." Doctoral thesis, Università di Catania, 2015. http://hdl.handle.net/10761/3848.

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Nature shows as human beings live and grow inside social structures. This assumption allows explaining and exploring how it may shape most of our behaviours and choices, and why we are not just blindly driven by instincts: our decisions are based on more complex cognitive reasons, based on our connectedness on di erent spaces. Thus, human cooperation emerges from this complex nature of social network. One of the main aims of my Ph.D. dissertation is to explore how and why it happens, hence the work is mainly focused on studying the evolutionary dynamics of cooperation and social behaviours on a multilayer social network. Following a Bio-inspired approach, the social network analysis methodologies, and exploiting the mathematical framework of Evolutionary Game Theory (EGT), the target is to unveil the hidden dynamics, observe non-trivial patterns, nding out the hidden emergent behaviours in a population. The study of cooperation and its evolutionary dynamics on a social network, has raised up the need of a model able to explain the actual complexity of real-world networks, where individuals are connected through multiple types of relationships. For this reason, the mathematical framework of multilayer networks has been exploited, indeed it allows us to encompass these several interactions and relationships, exploring and unveiling how the di erent ties in the various layers can impact on the emergence of social behaviours in a population. Therefore, the presence of the same nodes in multiple layers of a system, known as multiplexity, is the key to understand emergent phenomena, adding an extra dimension of analysis which explains what is the role not only of the intralayer interactions, as in a single-layer framework, but also of interlayer interactions for the emergence of these phenomena. Furthermore, it is explored and quanti ed the role of some shaping factors, such as homophily, in this evolutionary process. Taking into account all these aspects, a novel analytical model is proposed, together with a simulative investigation of the evolution of human cooperation using mutliplex evolutionary game theory, shedding light on the key role played by homophily and multiplexity in the evolution of cooperation. (continue in Ph. D. dissertation)

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Wilmshurst, John F. "Foraging behaviour and spatial dynamics of Serengeti herbivores." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ35816.pdf.

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Funk, Sebastian. "The dynamics of contagious diseases and human behaviour." Thesis, Royal Holloway, University of London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.521414.

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Katsikides, Andrew. "Phase behaviour structure and dynamics of microemulsion systems." Thesis, University of Kent, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329298.

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Novik, Keir Erik. "Simulation of fluid behaviour using dissipative particle dynamics." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621679.

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Trujillo, Amezquita Frank. "Exotic and tame behaviour in quasi-periodic dynamics." Thesis, Université de Paris (2019-....), 2020. http://www.theses.fr/2020UNIP7042.

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Dans ce travail, nous étudions les conditions d'existence de phénomènes quasi périodiques et les implications de leur présence dans plusieurs systèmes dynamiques. Nous nous concentrerons principalement sur la dynamique hamiltonienne où nous fournissons des critères pour la persistance des mouvements quasi-périodiques associés à des tores résonants invariants (chapitre 2), explorons dans quelle mesure l'existence de mouvements quasi-périodiques caractérise le système (chapitre 3) et donnons des exemples des points fixes elliptiques instables avec deux degrés de liberté (chapitre 4). Pour les homéomorphismes critiques du cercle (chapitre 5), nous établissons une relation entre la dimension de Hausdorff de leurs mesures invariantes et leur nombre de rotation. Dans la dernière partie de cette thèse (chapitre 6) nous prouvons, à l'aide des approximations périodiques localisées, l'existence de transformations lisses à entropie nulle mélangeants sur T3 dont le produit avec elles-mêmes est lâchement Bernoulli
In this work we study conditions for the existence of quasi-periodic phenomena and the implications of their presence in several dynamical systems. Our main focus will be Hamiltonian dynamics where we provide criteria for the persistence of quasi-periodic motions associated to invariant resonant tori (Chapter 2), explore to what extent the existence of quasi-periodic motions characterize the system (Chapter 3) and give examples of unstable elliptic equilibria with two degrees of freedom (Chapter 4). For critical circle homeomorphisms (Chapter 5) we establish a relation between the Hausdorff dimension of their invariant measures and their rotation number. In the last part of this thesis (Chapter 6) we prove, by means of localized periodic approximations, the existence of mixing zero entropy smooth transformations on T3 whose product with themselves is loosely Bernoulli

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Seaman, Matthew. "Computational models of structure and dynamics." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362082.

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Liu, Jianhui. "Dynamic behaviour of rigid-plastic beams." Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.480541.

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Dissertations / Theses on the topic 'Behavioural dynamics'

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