Dissertations / Theses on the topic 'Dynamic ageing'
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Venables, R. "Dynamic strain ageing and the fatigue behaviour of nimonic 901." Thesis, University of Nottingham, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376646.
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Mohammad, Naim Nur Nafisah. "Modelling the ageing behaviour of supercapacitors using electrochemical impedance spectroscopy for dynamic applications." Thesis, University of Nottingham, 2015. http://eprints.nottingham.ac.uk/29169/.
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Diagnosis of ageing mechanisms in supercapacitors is made difficult by the enforcement of various ageing factors in the current ageing tests. The thesis presents the exact determination of the ageing mechanism by separating the impacts of high temperature, current cycling and constant voltage applications in accelerated ageing tests. The state of health (SOH) of the supercapacitors are monitored periodically with electrochemical impedance spectroscopy, cyclic voltammetry and constant current test to observe the evolution of ageing. The thesis identifies patterns of ageing from the changes at supercapacitor impedance. The thesis also presents the cause of the increase in ESR and the loss of capacitance in supercapacitors. High temperature application causes the appearance of high frequency semicircle which reflects the damage at the electrode-current collector interface. A tilt of the impedance line at low frequencies reflects modifications of electrodes and it is most sensitive to current cycling and constant voltage applications. The increase in ESR is observed to be caused by a single ageing mechanism while the capacitance loss is caused by multiple interactions of these ageing mechanisms at the same time. The thesis develops a supercapacitor model by means of electrical equivalent circuit. The model is divided into two parts based on the changes in its SOH: the baseline model represents the early stage of the supercapacitor life and the ageing model represents the phase of ageing. The models show dynamic interactions between ageing process and supercapacitor electrical performance. The supercapacitor model, in the form of fractional-order model, reduces the number of circuit components and shows excellent electrical behaviour particularly at the open circuit voltage decay and voltage recovery period. The parameterisation of model parameters shows that aged supercapacitors experience an increase of distributed resistance in the electrode pores and an increase of diffusion impedance at high temperature.
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Martinez, Vincent Arnaud, and vincent martinez@student rmit edu au. "New Insights into the Mechanisms of Crystallisation and Vitrification - a Dynamic Light Scattering Study of Colloidal Hard Spheres." RMIT University. Applied Sciences, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091007.102126.
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This thesis reports on a comprehensive experimental study of the collective dynamics of colloidal hard sphere suspensions. The main quantity measured is the coherent Intermediate Scattering Function (ISF) using a range of techniques based on Dynamic Light Scattering (DLS). The collective dynamics are measured as a function of scattering vector for volume fractions spanning from dilute samples, through the fluid phase and the metastable region, up until deep in the glass region. This work describes two major explorations: (i) the effect of volume of fraction on the q-dependency of the collective dynamics; and (ii) a study of the ageing processes in colloidal glasses. The present work is unique in the application of several advanced experimental techniques, and in the level of averaging that has been carried out, enabling a more sophisticated analysis than has previously been possible. This includes the characterization of non-Fickian processes and the determinatio n of the current-current correlation function (CCCF) in the metastable fluid, and the quantitative characterization of the ageing process in the hard sphere glass. In addition, by combining aspects of the coherent and incoherent ISFs, this work also allows the expression of the collective dynamics in terms of the single particle displacement. The results show a dynamical change at the freezing point (f), which exposes the incapacity of the system to dissipate thermal energy via diffusing momentum currents, i.e. viscous flow. The structural impediments responsible for this, associated with dynamical heterogeneities, begin at the structure factor peak, and spread to other spatial modes as the volume fraction increases. Above the glass transition (g), structural relaxation becomes arrested at all spatial modes probed, i.e. flow is arrested. It is found that, following the quench, samples above the glass volume fraction approach some final
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Gorp, Adrianus Wilhelmus van. "The relationship between structural and in vivo dynamic mechanical properties of the thoracic aorta in rats influence of ageing and hypertension /." Maastricht : Maastricht : Universiteit Maastricht ; University Library, Maastricht University [Host], 1999. http://arno.unimaas.nl/show.cgi?fid=7537.
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Gustafsson, Patrik. "Design of Experimental Setup for Investigation of Effect of Moisture Content on Transformer Paper Ageing during Intermittent Load." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-232187.
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In this project an experimental setup is designed to investigate the effect of intermittent load patterns in combination with moisture content on cellulose ageing. It is done by exposing groups of samples to different intermittent load patterns with varying frequency. A literature review is done on transformer insulation system and cellulose degradation. Various technical solutions to different aspects of the experimental design are reviewed. The final experimental setup is explained with the primary focus being on the hardware and programming of the controlling system. The controlling system consists of a Data Acquisition (DAQ) system from National Instruments and is programmed in LabVIEW. The controlling system is examined in two investigative tests where it performed satisfactorily. Three load patterns are developed. This project suggests how to prepare the samples and what direct- and indirect tests to apply to the insulation system for future analysis.Over the years, a considerable amount of scientific work has been devoted to understanding paper ageing in order to improve transformer diagnostics and investments for utility owners. However, transformer loading guidelines of today do not take intermittent load in combination with moisture content into account [1] [2]. Previous work suggests that the thermal models may be improved by looking into the effects of moisture content [3].The primary aim of the proposed experimental setup is to investigate whether an intermittent load pattern in combination with moisture content have a considerable detrimental effect on cellulose ageing. The intent is to contribute with new knowledge about transformer diagnostics and long-term possibly improve the current thermal models used for Dynamic Transformer Rating (DTR) which do not take this phenomenon into account. This would in particular benefit transformers with typically intermittent load patterns, e.g. a transformer connected to a wind farm or photovoltaic panels. Increasing renewable energy installations increase the need for developing the thermal models in the transformer loading guidelines to take unconventional load profiles into account.I det här projektet utformas ett experiment för att undersöka inverkan av intermittenta lastmönster i kombination med fukthalt på åldrande av cellulosa. Detta görs genom att utsätta provgrupper för olika lastmönster med varierande frekvens. En litteraturgenomgång görs på transformatorisoleringssystem och nedbrytning av cellulosa. Olika tekniska lösningar för olika aspekter av experimentets design ses över. Den slutliga utformningen av experimentet förklaras med fokus på hårdvara och programmering av kontrollsystemet. Kontrollsystemet består av ett system för datainsamling från National Instruments och programmeras i LabVIEW. Kontrollsystemet utvärderas i två undersökande test där det förfor på ett tillfredsställande sätt. Tre lastmönster till experimentet har tagits fram. Det här projektet föreslår hur man förbereder proverna och vilka direkta och indirekta test som kan göras för framtida analyser.Under åren har en betydande mängd vetenskapligt arbete ägnats åt att förstå pappersåldring för att förbättra transformatordiagnostik och investeringsunderlaget för nätägare. De industriella standarderna tar dock inte hänsyn till intermittent belastning i kombination med fukthalt [1] [2]. Tidigare arbete föreslår att de termiska modellerna möjligen kan förbättras genom att undersöka effekterna av fukthalt [3].Det huvudsakliga målet med den föreslagna experimentella uppställningen är att undersöka huruvida ett intermittent belastningsmönster i kombination med fukthalt har en betydande inverkan på pappersåldrandet. Föresatsen är att bidra med ny kunskap om transformatordiagnostik och för att om möjligt långsiktigt förbättra de nuvarande termiska modellerna som används till dynamiska lastbarhetsmodeller för transformatorer. Detta skulle särskilt gynna transformatorer med typiskt intermittenta belastningsmönster, t ex en transformator ansluten till en vindkraftpark eller solcellspaneler. Ökande antal av anläggningar för förnybar energi ökar behovet av att utveckla de termiska modellerna för att ta hänsyn till okonventionella lastprofiler.
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Pěnčík, Michal. "Reologické vlastnosti asfaltových pojiv." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227653.
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The Diploma thesis is focused on rheological properties of bituminous binders and mixtures. Above all, it describes the changes of these properties of samples of bituminous binders and mixtures. Those were brought by the process of laboratory aging, since it simulates the changes occurring in the in the real-life conditions. The theoretical part depicts the field of rheology and methods utilized for simulating the ageing of binders and mixtures. The practical part describes the process of preparation of samples and its testing. Firstly, the ageing of bituminous mixture by the means of BSA method (Braunschweiger Alterung) took place, which was followed by preparing the solids for testing the modulus of stiffness and main testing. The rest of the mixture was used for extracting the binder. Tests with the binder were focused on the usage of dynamic shear rheometer (complex shear modulus, dynamic viscosity). The last part of the work is dedicated to the comparison of the outcomes of testing.
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Makówka, Tomasz. "Diagnostika vlastností elektroizolačních kapalin." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218544.
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The diploma thesis deals with the liquid insulators, their properties and their use in the electrical industry. The general aim is to study the physical essence of the dynamic viscosity, the electric conductivity and the diagnostic methods for monitoring these variables. The experimental part contains measuring the dynamic viscosity and the electric conductivity of the mineral transformer oils ESTO BNX, RENOLIN ELTEC and the biodegradable oil MIDEL 7131 during the degradation. The Walden rule is applied on measured results.
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Střasáková, Monika. "Stárnutí asfaltových pojiv." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240117.
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The theoretical part of this thesis describes the rheology of bituminous binders, aging of asphalt binders and laboratory methods simulating short and long term aging. The following describes an empirical tests (needle penetration, softening point ring ball method) and functional tests (complex shear modulus and phase angle, dynamic viscosity), which are performed in the dynamic shear rheometer. At the end of this section, laboratory aging of bituminous binders using method RTFOT and method RTFOT + PAV is described in more detail. In the practical part of this thesis, the results of all tests performed on the binders aged using RTFOT + PAV are introduced and compared with results of properties of non-aged binders and binders aged by 3xRTFOT.
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Axelsson, Gary. "Long-term set-up of driven piles in sand." Doctoral thesis, KTH, Civil and Environmental Engineering, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3009.
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Hu, Xiaolong. "Impact of climate change on power systems." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/impact-of-climate-change-on-power-systems(2132a62f-afa2-4d91-8381-5ec8643b97b4).html.
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The global mean surface temperature rise was observed in the past century and proved the warming of the earth climate system. Global warming is believed to continue into the next decades due to unprecedented increases in greenhouse gas emissions. As a consequence of global warming, extreme weather scenarios are also expected to occur more frequently. In such a context, it is of vital importance to assess the impacts of climate change on the operational performance of power systems. This thesis investigates the impacts of climate change on the operational performance of power systems. The future climate is simulated based on emission scenarios and is then used as an input to the thermal models of power system components to assess their ratings and ageing, and further the reliability of the system. This research contributes to a number of areas in power system research. In the literature review, the risks that climate change may cause to power systems are identified. The models used for the simulation of future climate are firstly introduced. The weather variables that can be simulated from the models include air temperature, solar radiation, wind speed and direction, soil moisture and soil temperature. Among the models, the one for soil temperature is originally developed in this thesis. Following this, the component thermal models of overhead line, cable and transformer, from different standards are compared and selected. After that, the sensitivity of component ratings to individual weather variables is investigated, as a preliminary study for the later research in this thesis. Then, the impacts of climate change on component ratings (including both static and dynamic rating) are comprehensively and probabilistically assessed. The assessment results indicate the reduction of component ratings due to climate change. The impacts of climate change on system reliability is further examined on the IEEE Reliability Test System. Results demonstrate and quantify the reduction of both component ratings and system reliability, and prove that the dynamic rating can be used to mitigate the reduction. Finally, the preliminary exploration of transformer ageing is carried out and shows an increased ageing rate due to air temperature rises.
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Ali, Mahdi. "Study of the bitumen aging effects on the rheological properties and fatigue behavior." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16255/.
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A study of bitumen aging effects on the rheological properties and fatigue behavior is carried out on five polymer modified bitumen provided by an oil company. Dynamic Shear Rheometer (DSR), is used to perform advanced experimental investigation. It allows practicing frequency sweep tests, fatigue tests and time sweep tests. Polymer modified bitumen with different percentage of SBS with or without the presence of crumb rubber are tested before and after short and long aging processes.
Master curves were generated based on frequency sweep tests data, they are studied, and a comparison was conducted between each bitumen before and after aging. In this thesis, the DSR is presented, as well as the testing procedure and the tested materials. A fatigue life analysis of the results, based on the use of two different criteria, the first criterion is classically used: it consists in defining the failure as a 50% loss of the initial stiffness. The other criteria based on dissipated energy data.
This thesis provides results which show the effects of several factors on fatigue and healing response such as bitumen type, ageing, the presence of rubber and polymer modification.
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Augustine, Starrlight. "Metabolic programming of zebrafish, Danio rerio uncovered : Physiological performance as explained by Dynamic Energy Budget Theory and life-cycle consequences of uranium induced perturbations." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM4708/document.
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Ce travail de thèse s'est intéressé aux effets de l'uranium appauvri (U) sur le poisson zèbre, Danio rerio. L'hypothèse de travail majeure est que les effets de l'U peuvent se traduire par des modifications du métabolisme. Par conséquent nous avons caractérisé la performance physiologique par le biais de la théorie des bilans d'énergie dynamique (DEB) car c'est la seule théorie qui quantifie simultanément l'ingestion, l'assimilation, la croissance, la reproduction, la maturation, la maintenance et le vieillisse¬ment au cours du cycle de vie entier à des niveaux de nourriture variable. Un modèle DEB a ainsi été construit et a permis de quantifier et de prédire la manière dont la performance physiologique du poisson zèbre dépend de son niveau de nutrition (et de la température). Nous avons montré que le développement s'accélère après la naissance jusqu'à la métamorphose où l'accélération cesse. De plus les coûts de maintenance somatique sont très élevés.Un module spécifiant la toxico-cinétique de l'U, chez un individu qui se nourrit, croit et se reproduit, a été incorporé dans le modèle DEB. Le modèle a été appliqué aux données de toxicité (publiés et acquis pendant la thèse) afin de découvrir quel processus est affecté par l'U. Les résultats montrent qu'à partir de 0 nM, l'U augmenterait les coûts de croissance et diminuerait l'assimilation et/ou augmenterait le coût de la maintenance somatique. Nous n'avons pas pu détecter d'effets notables sur la maturation. Une étude histologique révèle que l'U altère l'intégrité de la paroi intestinale et pourrait perturber l'homéostasie des interactions hôte-bactériesThe aim of this dissertation is to characterize the toxicity of depleted uranium (U) on the metabolism of zebrafish, Danio rerio. The underlying hypothesis of this work is that effects of U show up as effects on the metabolism of the individual. Consequently, we characterized physiological performance using Dynamic Energy Budget (DEB) theory since it is the only theory which simultaneously specifies ingestion, assimilation, growth, reproduction, maturation, maintenance and ageing over the whole life-cycle at varying food availability. Thus a DEB model was built which quantifies and predicts how the physiological performance of zebrafish relates to food level (and temperature). We showed that development accelerates after birth until metamorphosis after which acceleration ceases. Furthermore, somatic maintenance costs are very high.A module specifying toxico-kinetics of U in a feeding, growing and reproducing individual was incorporated into the DEB model. The model was then applied to toxicity data (from the literature or acquired during this thesis) in order to determine which processes are affected by U. Our results show that, from 0 nM onwards, U increases costs for growth and either increases somatic maintenance or decreases assimilation. We were unable to detect effects on maturation. A histological study showed that U alters histology of the gut wall and may perturb host-microbe homeostasis. By accounting for differences in initial conditions between individuals we were able to explain a number of seemingly contradictory results. The take home message is: observations on individuals should not be averaged for groups of individuals
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Štěpanovský, Vlastimil. "Problematika stárnutí asfaltových pojiv a směsí." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227164.
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Diploma thesis is particularly focused on ageing of asphalt mixtures and asphalt binders. In the theoretical part an array of methods simulating short term and long term ageing consequently is introduced. The main objective of the practical part was to carry out the long-term ageing test method BSA (Braunschweiger Alterung). Thereafter, specimens testing for stiffness properties according to CSN EN 12697-26 were made. After conducting the measurement on those, asphalt binder was extracted and processed to follow-up testing. The testing consisted of a range of methods – Penetration CSN EN 1426, Ring and Ball test CSN EN 1427, Determination of the Frass breaking point CSN EN 12593, Determination of complex shear modulus CSN EN 14770 and Dynamic viscosity using a dynamic shear rheometer (DSR). The given results were assessed in the last part in order to evaluate the rate of the binder degradation caused by the method BSA.
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Hotař, Petr. "Reologické vlastnosti asfaltových pojiv." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226951.
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The comparison of rheological properties (complex shear modulus and phase angle and dynamic viscosity) of four paving bitumens and two polymer modified bitumens is performed in this diploma thesis. Furthermore, the empirical tests (needle penetration and softening point) were determined on these binders. Effect of asphalt binders aging was modeled using RTFOT test and modified RTFOT test (3 x RTFOT).
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Marangoni, Pauline. "Unraveling development and ageing dynamics of the rodent dentition." Thesis, Lyon, École normale supérieure, 2014. http://www.theses.fr/2014ENSL0965/document.
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L’évolution de la denture des vertébrés est un sujet majeur et des plus intéressants en biologie développementale évolutive (évo-dévo). Dans ce domaine, la souris Mus musculus est traditionnellement l’animal modèle utilisé. La denture de la souris inclus quatre incisives à croissance continue et douze molaires présentant une organisation caractéristique de leurs cuspides. Le réseau moléculaire régulant le développement de ces deux types de dents est très spécifique.La cascade ERK-MAPK est impliquée lors de différentes étapes du développement dentaire. Une étude comparée du phénotype des molaires de souris mutantes pour des gènes activés à différents points de la cascade a démontré l’existence d’un phénotype caractéristique, à savoir la présence d’une dent surnuméraire en position mésiale des rangées de molaires, ainsi que la présence d’anomalie dans le nombre et la forme de certaines cuspides. Parmi ces caractères présents chez les mutants, certains rappellent des caractères ancestraux présents uniquement chez des rongeurs fossiles. Ceci appuie le rôle que la cascade ERK-MAPK a pu jouer au cours de l’évolution de la denture chez les rongeurs. En travaillant sur une lignée transgénique sur-exprimant un inhibiteur de cette cascade, j’ai pu perfectionner notre connaissance du rôle des gènes de la famille Fgf dans les processus de mise en place des centres de signalisation dentaire et de minéralisation de l’émail.Si l’on considère les incisives à croissance continue, la denture de la souris est dynamique à l’échelle de la vie d’un individu. Réalisant un suivi des incisives supérieures d’une cohorte de souris au cours de leur vieillissement, j’ai pu préciser la chronologie d’apparition de défauts liés au vieillissement. Ces défauts apparaissent sur les incisives à partir de six mois, et le plus fréquent est le développement d’un sillon visible sur l’émail de l’incisive. J’ai enfin utilisé des techniques de séquençage de nouvelle génération (NGS) pour comprendre les bases moléculaires du vieillissement des niches de cellules souches des incisives. Ce faisant, j’ai détecté des changements dans les profils d’expression de gènes régulant le maintien des cellules souches, la prolifération cellulaire et le métabolisme. La présence d’un sillon apparaît corrélée à une forte réponse immunitaire détectée dans les tissus dentaires, ce qui constitue une perspective d’étude majeure dans le but d’achever la caractérisation du vieillissement des cellules souches dentairesThe evolution of the vertebrate dentition is among the most exciting topics in the evo-devo field, with particular attention being drawn to the mouse model. The mouse dentition includes four ever-growing incisors and twelve molars with a specific cusp pattern. Incisors and molars develop according to a tightly regulated molecular network.The ERK-MAPK cascade is involved at various stages of tooth development. Molar tooth phenotype comparisons in mutant mice for genes acting at various levels of the cascade highlighted a dental phenotype signature, which consists in the presence of a supernumerary tooth and shared cusp pattern defects. Some of these recall characters present in fossil rodents, supporting the ERK-MAPK as a good candidate to explain some evolutionary trends of the rodent dentition. By working on a mouse line over-expressing one of this pathway inhibitor in the oral epithelium, I perfect our understanding of Fgf gene role in specifying signaling center formation at the right stage, and in achieving correct mineralization.When considering evergrowing incisors, mouse dentition is also dynamic at the lifetime scale. I monitored the ageing process of the mouse upper incisors, and provided a chronology of occurrence of the variety of age-related defects display. These defects are set up from the six months on, the most frequent abnormality being the presence of an enamel groove along the surface of the incisor. Using Next Generation Sequencing technologies, I detected transcriptomic changes in the stem cell niches affecting cell proliferation and metabolism, as well as the stem cell niche functioning. The correlation found between the groove occurrence and a large immune response in dental tissues expands our concern for dental stem cell ageing
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Noble, Jane Mary. "Cell membrane dynamics and signal transduction in human ageing." Thesis, University of Newcastle Upon Tyne, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324872.
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Walker, Joan. "British contemporary fiction and the new dynamics of ageing." Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/12546.
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This Ph.D. thesis consists of a novel, EXEUNT, and research associated with it, both being specifically concerned with literary/cultural representations of love and relationships over the age of sixty-five. In consideration of the changing dynamics of ageing, declared internationally by gerontologists during the 1990s, the research investigates the perceptions of British writers, publishers and readers regarding their acceptance of late-life sexuality in British contemporary novels. It identifies key stakeholders in specific interest groups, and operates within an interpretive perspective as a suitable analytical framework for a pragmatic mixed methods investigation. Although the initial focus of the research was on publishers and writers, the inclusion of readers resulted in wider consequences that call for more transparency and a fuller understanding of concepts linked to ageism. Having explored the dynamic between author, publisher and reader, the study concludes there is a superficial disharmony between them, whereas in fact they are mutually complementary. This dichotomy appears to be due to misunderstanding, and lack of trust. In reality, a large percentage of readers, in line with recent research on film audiences, feel it acceptable for people over the age of sixty to have such sexual needs and desires. This acceptability and the new dynamics of ageing inform the novel which places the research in a wider context and constitutes the second part of the Ph.D. The multi-layered novel EXEUNT, in part ontogenetic, works against ageism within current prejudice by depicting the lovers in their fifties, sixties and seventies, and by doing so reveals the wide gap between subjective reality and the perceived public image. Their relationship is accepted by the British woman s friends, family and contemporaries, so that the epistemology of age is acquired only through negative opinions or actions, with the narrative embodying much of current research on the subject. Contrasting attitudes to ageing are found within the ethnographic detail of Romania during the period of communism, revolution and consequential freedom: 1982-2005. The frameworks of the fiction are encapsulated in the concept of Theatre as an analogy for life and death with a unique structure that portrays an ontological viewpoint. This underpins a reality where the attention of the reader/audience is disrupted by an intermittent reminder of the analogy. The term fictodrama has been used to describe this combination of fiction and theatrical effects.
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Zábranský, Ivo. "Vlastnosti nízkoteplotních polymerem modifikovaných asfaltů." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392123.
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The Diploma thesis is focus on polymer modified bitumen for warm mix asphalt. The theoretical part of the thesis describes additives which influence the properties of bitumen for their use and reduction of production and service temperatures. Further, the theoretical part describes the conclusions from the researches. This part also describes empirical and functional tests of bituminous binders. The practical part presents the results of individual tests. Tests were performed on samples of non-aged, aged by RTFOT and RTFOT + PAV methods. The results of the work and the assessment of the suitability of bituminous binders are summarized at the end of the thesis.
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Dostál, Filip. "Vliv druhu a dávky polymeru na vlastnosti modifikovaných pojiv." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2020. http://www.nusl.cz/ntk/nusl-409806.
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The diploma thesis is focused on polymer modified binders with different polymer doses. The theoretical part describes the history of the use of bitumen, the extraction of bitumen from oil and behavious of the polymer type SBS/SB, which is used in the diploma thesis on modified binders. Further, the theoretical part describes the empirical and functional tests of bitumen binders. In the practical part the results of indidual tests are presented and compared with the standard ČSN 65 7222-1. At the end of the diploma thesis are summarized results of work and evaluation of binders with the best achieved properties.
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Roewe, James M. "Fault tolerant dynamic agent systems." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33347.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references (p. 67-68).
Partial system snapshots reduce the cost per node to only depend on the size of the connected group instead of the size of the full system. These groups can be determined during system operation by using the communication patterns between nodes. The number of nodes that must rollback after a failure is limited to the size of these snapshot groups, reducing the work lost. These changes to snapshot algorithms are necessary because the cost per node for a snapshot increases and the expected time between failures decreases as the size of the system grows.
by James M. Roewe.
M.Eng.
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Alberola, Oltra Juan Miguel. "Reorganization in Dynamic Agent Societies." Doctoral thesis, Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/19243.
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En la nueva era de tecnologías de la información, los sistemas tienden a ser cada vez más
dinámicos, compuestos por entidades heterogéneas capaces de entrar y salir del sistema,
interaccionar entre ellas, y adaptarse a las necesidades del entorno. Los sistemas multiagente han
contribuído en los ultimos años, a modelar, diseñar e implementar sistemas autónomos con
capacidad de interacción y comunicación. Estos sistemas se han modelado principalmente, a través
de sociedades de agentes, las cuales facilitan la interación, organización y cooperación de agentes
heterogéneos para conseguir diferentes objetivos. Para que estos paradigmas puedan ser utilizados
para el desarrollo de nuevas generaciones de sistemas, características como dinamicidad y
capacidad de reorganización deben estar incorporadas en el modelado, gestión y ejecución de estas
sociedades de agentes.
Concretamente, la reorganización en sociedades de agentes ofrece un paradigma para diseñar
aplicaciones abiertas, dinámicas y adaptativas. Este proceso requiere determinar las consecuencias
de cambiar el sistema, no sólo en términos de los beneficios conseguidos sinó además, midiendo los
costes de adaptación así como el impacto que estos cambios tienen en todos los componentes del
sistema. Las propuestas actuales de reorganización, básicamente abordan este proceso como
respuestas de la sociedad cuando ocurre un cambio, o bien como un mecanismo para mejorar la
utilidad del sistema. Sin embargo, no se pueden definir procesos complejos de decisión que
obtengan la mejor configuración de los componentes organizacionales en cada momento, basándose
en una evaluación de los beneficios que se podrían obtener así como de los costes asociados al
proceso.
Teniendo en cuenta este objetivo, esta tesis explora el área de reorganización en sociedades de
agentes y se centra principalmente, en una propuesta novedosa para reorganización. Nuestra
propuesta ofrece un soporte de toma de decisiones que considera cambios en múltiplesAlberola Oltra, JM. (2013). Reorganization in Dynamic Agent Societies [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/19243
Palancia
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Islam, Mohammad Saiful. "The Influence of Fibre Processing and Treatments on Hemp Fibre/Epoxy and Hemp Fibre/PLA Composites." The University of Waikato, 2008. http://hdl.handle.net/10289/2627.
Full textAbstract:
In recent years, due to growing environmental awareness, considerable attention has been given to the development and production of natural fibre reinforced polymer (both thermoset and thermoplastic) composites. The main objective of this study was to reinforce epoxy and polylactic acid (PLA) with hemp fibre to produce improved composites by optimising the fibre treatment methods, composite processing methods, and fibre/matrix interfacial bonding. An investigation was conducted to obtain a suitable fibre alkali treatment method to: (i) remove non-cellulosic fibre components such as lignin (sensitive to ultra violet (UV) radiation) and hemicelluloses (sensitive to moisture) to improve long term composites stability (ii) roughen fibre surface to obtain mechanical interlocking with matrices (iii)expose cellulose hydroxyl groups to obtain hydrogen and covalent bonding with matrices (iv) separate the fibres from their fibre bundles to make the fibre surface available for bonding with matrices (v) retain tensile strength by keeping fibre damage to a minimum level and (vi) increase crystalline cellulose by better packing of cellulose chains to enhance the thermal stability of the fibres. An empirical model was developed for fibre tensile strength (TS) obtained with different treatment conditions (different sodium hydroxide (NaOH) and sodium sulphite (Na2SO3) concentrations, treatment temperatures, and digestion times) by a partial factorial design. Upon analysis of the alkali fibre treatments by single fibre tensile testing (SFTT), scanning electron microscopy (SEM), zeta potential measurements, differential thermal analysis/thermogravimetric analysis (DTA/TGA), wide angle X-ray diffraction (WAXRD), lignin analysis and Fourier transform infrared (FTIR) spectroscopy, a treatment consisting of 5 wt% NaOH and 2 wt% Na2SO3 concentrations, with a treatment temperature of 120oC and a digestion time of 60 minutes, was found to give the best combination of the required properties. This alkali treatment produced fibres with an average TS and Young's modulus (YM) of 463 MPa and 33 GPa respectively. The fibres obtained with the optimised alkali treatment were further treated with acetic anhydride and phenyltrimethoxy silane. However, acetylated and silane treated fibres were not found to give overall performance improvement. Cure kinetics of the neat epoxy (NE) and 40 wt% untreated fibre/epoxy (UTFE) composites were studied and it was found that the addition of fibres into epoxy resin increased the reaction rate and decreased the curing time. An increase in the nucleophilic activity of the amine groups in the presence of fibres is believed to have increased the reaction rate of the fibre/epoxy resin system and hence reduced the activation energies compared to NE. The highest interfacial shear strength (IFSS) value for alkali treated fibre/epoxy (ATFE) samples was 5.2 MPa which was larger than the highest value of 2.7 MPa for UTFE samples supporting that there was a stronger interface between alkali treated fibre and epoxy resin. The best fibre/epoxy bonding was found for an epoxy to curing agent ratio of 1:1 (E1C1) followed by epoxy to curing agent ratios of 1:1.2 (E1C1.2), 1: 0.8 (E1C0.8), and finally for 1:0.6 (E1C0.6). Long and short fibre reinforced epoxy composites were produced with various processing conditions using vacuum bag and compression moulding. A 65 wt% untreated long fibre/epoxy (UTLFE) composite produced by compression moulding at 70oC with a TS of 165 MPa, YM of 17 GPa, flexural strength of 180 MPa, flexural modulus of 10.1 GPa, impact energy (IE) of 14.5 kJ/m2, and fracture toughness (KIc) of 5 MPa.m1/2 was found to be the best in contrast to the trend of increased IFSS for ATFE samples. This is considered to be due to stress concentration as a result of increased fibre/fibre contact with the increased fibre content in the ATFE composites compared to the UTFE composites. Hygrothermal ageing of 65 wt% untreated and alkali treated long and short fibre/epoxy composites (produced by curing at 70oC) showed that long fibre/epoxy composites were more resistant than short fibre/epoxy composites and ATFE composites were more resistant than UTFE composites towards hygrothermal ageing environments as revealed from diffusion coefficients and tensile, flexural, impact, fracture toughness, SEM, TGA, and WAXRD test results. Accelerated ageing of 65 wt% UTLFE and alkali treated long fibre/epoxy (ATLFE) composites (produced by curing at 70oC) showed that ATLFE composites were more resistant than UTLFE composites towards hygrothermal ageing environments as revealed from tensile, flexural, impact, KIc, SEM, TGA, WAXRD, FTIR test results. IFSS obtained with untreated fibre/PLA (UFPLA) and alkali treated fibre/PLA (ATPLA) samples showed that ATPLA samples had greater IFSS than that of UFPLA samples. The increase in the formation of hydrogen bonding and mechanical interlocking of the alkali treated fibres with PLA could be responsible for the increased IFSS for ATPLA system compared to UFPLA system. Long and short fibre reinforced PLA composites were also produced with various processing conditions using compression moulding. A 32 wt% alkali treated long fibre PLA composite produced by film stacking with a TS of 83 MPa, YM of 11 GPa, flexural strength of 143 MPa, flexural modulus of 6.5 GPa, IE of 9 kJ/m2, and KIc of 3 MPa.m1/2 was found to be the best. This could be due to the better bonding of the alkali treated fibres with PLA. The mechanical properties of this composite have been found to be the best compared to the available literature. Hygrothermal and accelerated ageing of 32 wt% untreated and alkali treated long fibre/PLA composites ATPLA composites were more resistant than UFPLA composites towards hygrothermal and accelerated ageing environments as revealed from diffusion coefficients and tensile, flexural, impact, KIc, SEM, differential scanning calorimetry (DSC), WAXRD, and FTIR results. Increased potential hydrogen bond formation and mechanical interlocking of the alkali treated fibres with PLA could be responsible for the increased resistance of the ATPLA composites. Based on the present study, it can be said that the performance of natural fibre composites largely depend on fibre properties (e.g. length and orientation), matrix properties (e.g. cure kinetics and crystallinity), fibre treatment and processing methods, and composite processing methods.
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Lim, Yusun Lee. "Potential game based cooperative control in dynamic environments." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/39511.
Full textAbstract:
The objectives of this research are to extend cooperative control methods based on potential games to dynamic environments and to develop an experimental test bed to illustrate theoretical results. Cooperative control concerns coordinating a collective performance of multiple autonomous agents. Possible applications include mobile sensor networks, distributed computation, and unmanned vehicle teams. Prior work has explored game theory, specifically the framework of potential games, as an approach to cooperative control, but has been restricted to static environments.
This research shows that potential game based cooperative control also can be applied to dynamic environment problems. The approach is illustrated on three example problems. The first one is a moving target tracking problem using a modified form of the learning algorithm, restrictive log-linear learning. The second example is mobile sensor coverage for an unknown dynamic environment. The last example is multi-agent path optimization using payoff based learning. The performances of the developed systems are studied by simulation. The last part of this thesis develops an experimental moving target tracking system using multiple mobile robots. Finally, the thesis concludes with suggestions for future research directions.
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Fielding, Suzanne. "Ageing, driving and effective temperatures : from 'soft rheology' to glassy dynamics." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/10901.
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This thesis studies non-equilibrium dynamics in disordered "glassy" systems, focusing particularly on the response to such systems to external driving and loading. Its primary motivation is a body of experimental data suggesting that glassy dynamics underlie the mechanical properties (rheology) of a wide variety of disordered soft materials (e.g. foams, dense emulsions and dense colloidal suspensions): typically, such materials show pronounced non-linearity in their stress response to slow steady shear (often with a yield stress in the limit of zero shear) and a loss modulus which curves upwards slightly to low frequencies (in apparent violation of linear response theory). In what follows, can, when rheologically driven, broadly capture this behaviour. We also show that they predict ageing at small loads, in qualitative agreement with the results of recent ageing experiments. Beyond this rheological motivation, we also use the models to study more general concepts of glassy dynamics, such as the use of fluctuation-dissipation theorems (FDTs) for defining effective non-equilibrium temperatures. As a preliminary step, we extend the existing rheological formalism to include ageing materials in which time-translational invariance (TTI) is lost. Within this generalized framework, we then analyze the rheologically driven trap model - the "soft glassy rheology" (SGR) model - which considers an ensemble of elastic elements undergoing activated local yielding dynamics, with distributed yield thresholds, governed by a noise temperature x. (Between yields, each element follows affinely the applied shear). We review the model's exact constitutive solution and discuss its mapping, in the undriven limit, to Bouchaud's trap model. We exploit this mapping to demonstrate the existence (in linear rheology at least) of an ageing glass phase (x < 1), in which the relaxation time is always of order the sample age.
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Philipov, Dimiter, Anne Goujon, and Giulio Paola Di. "Ageing dynamics of a human-capital-specific population: A demographic perspective." Max Planck Institute for Demographic Research, 2014. http://dx.doi.org/10.4054/DemRes.2014.31.44.
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Background: Research on how rising human capital affects the consequences of population ageing rarely considers the fact that the human capital of the elderly population is composed in a specific way that is shaped by their earlier schooling and work experience. For an elderly population of a fixed size and age-sex composition, this entails that the higher its human capital, the greater the total amount of public pensions to be paid.
Objective: The main purpose of this paper is to analyse the link between human capital and retiree benefits and its effect on population ageing from a demographic viewpoint.
Methods: We construct an old age dependency ratio (OADR), in which each person, whether in the numerator or the denominator, is assigned the number of units corresponding to his/her level of human capital. Based on data for Italy, we study the dynamics of this human-capital-specific OADR with the help of multistate population projections to 2107.
Results: Our results show that under specific conditions a constant or moderately growing human capital may aggravate the consequences of population ageing rather than alleviate them.
Conclusions: With those findings, the authors would like to stimulate the debate on the search for demographic and/or socio-economic solutions to the challenges posed by population ageing.
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Holzhauer, Sascha [Verfasser]. "Dynamic Social Networks in Agent-based Modelling : Increasingly Detailed Approaches of Network Initialisation and Network Dynamics / Sascha Holzhauer." Kassel : Kassel University Press, 2017. http://d-nb.info/1137030445/34.
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Nogueira, de Codes Rodrigo. "Vieillissements statique et dynamique et instabilités associées : expérimentation, modélisation et simulations numériques." Phd thesis, École normale supérieure de Cachan - ENS Cachan, 2011. http://tel.archives-ouvertes.fr/tel-00846955.
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L'objectif de cette thèse est d'étudier expérimentalement les phénomènes de vieillissement dus à la diffusion des atomes en solution dans les alliages d'aluminium et les instabilités qui leur sont associées comme le phénomène Portevin-Le Châtelier ou les bandes de Lüders et de proposer une modélisation de ces phénomènes dans le cadre de la thermodynamique des processus irréversibles. Une étude expérimentale détaillée est alors entreprise sur les alliages d'aluminium AA5083-H116 et AA5182-O. Le comportement du premier présente l'effet PLC de façon prononcée et les deux types d'instabilités sont observées simultanément pour le second. La corrélation d'images numériques et la thermographie infrarouge sont essentiellement employées pour détecter et caractériser les aspects spatiotemporels des instabilités observées. La déformation non homogène due à l'apparition et la propagation de bandes de localisation est mise en évidence. Ces bandes de déformation sont visualisées, permettant à leurs diverses caractéristiques (vitesse, orientation, largeur, vitesse de déformation à l'intérieur des bandes, augmentation de la température à l'intérieur des bandes) d'être mesurées sur des éprouvettes lisses (plates, cylindriques ou prismatiques). Dans le cas des éprouvettes plates, l'effet des épaisseurs de l'éprouvette a aussi été examiné. Les caractéristiques des bandes sont aussi analysées sur d'autres géométries d'éprouvette (entaillées avec divers types d'entailles) à des vitesses de déformation différentes pour exhiber leur morphologie en présence de chargements multiaxiaux. Des simulations non linéaires et tridimensionnelles ont été effectuées en utilisant le modèle de McCormick pour montrer comment la prise en compte des phénomènes de vieillissement, même partielle, permet de décrire les hétérogénéités et le mouvement des bandes de déformation ainsi que de prévoir leurs différentes caractéristiques. Enfin, en se basant sur les mécanismes physiques à la base des phénomènes de vieillissement et en soulignant les limites du modèle de McCormick, un modèle élasto-viscoplastique prenant en considération les phénomènes de vieillissement est proposé dans le cadre de la thermodynamique des processus irréversibles.
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Abakar, Malloum. "Analyse des mécanismes d'endommagement et du comportement vibratoire d'un composite à constituants naturels dans un environnement hydrique." Thesis, Le Mans, 2019. http://www.theses.fr/2019LEMA1020/document.
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Durant les dernières décennies, les composites polymères renforcés par des fibres végétales ont reçu une attention importante de la part des scientifiques. L’utilisation de fibres végétales permet en effet d’améliorer les performances environnementales de ces matériaux tout en atteignant des propriétés spécifiques plus élevées. Néanmoins, un verrou majeur freine encore le développement de ces matériaux. En effet, leur sensibilité au vieillissement hydrique, due à leur caractère hydrophile, restreint leur utilisation. Dans ce contexte, nous proposons, dans le cadre de cette thèse, d’analyser l’effet du vieillissement hydrique sur le comportement statique et dynamique, d’identifier et suivre les mécanismes d’endommagement d’une structure sandwiche biosourcée et ses constituants. Les composites utilisés sont constitués d'une résine greenpoxy associée à des fibres de lin et à une âme en liège pour les sandwichs. Dans la première partie, nous avons étudié le comportement en statique et en dynamique de la résine, du composite, des âmes et des sandwichs. Cette étude a conduit d’une part à la détermination des caractéristiques mécaniques et à l’identification et le suivi des mécanismes d’endommagement par émission acoustique et observations microscopiques et d’autre part à la détermination des caractéristiques dynamiques. Dans la deuxième partie, nous avons analysé la cinétique de diffusion d'eau dans la résine, les peaux, les âmes et les sandwichs par identification de leurs paramètres de diffusion par le modèle de Fick. En suite, nous sommes intéressés à l’impact du vieillissement hydrique sur le comportement et les propriétés mécaniques des sandwichs et ses constituantsIn recent decades, polymer composites reinforced with plant fibers have received significant attention from scientists. The use of reinforcing vegetable fibers makes it possible to improve the environmental performance of these materials reaching higher specific properties. Nevertheless, a major lock still hinders the development of these materials. Indeed, their sensitivity to water ageing, due to their hydrophilic nature, restricts their use. In this context, we propose, as part of this thesis, to analyze the effect of water ageing on static and dynamic behavior, to identify and monitoring the damage mechanisms of a sandwich structure biobased and its constituents. The composites used consist of a greenpoxy resin associated with flax fibers and a cork core for sandwich materials. In the first part of this work, we studied the static an dynamic behavior of the resin, the composites, cores and sandwich structures. This study led on the one hand to the determination of the mechanical characteristics and to the identification and the follow-up of the mechanisms of damage by acoustic emission and microscopic observations and on the other hand to the determination of the dynamic characteristics. In the second part, we first analyzed the kinetics of water diffusion in resin, skins, cores and sandwichs by identification of their diffusion parameters by the Fick model approach. Then, we are interested in the impact of water ageing on the behavior and mechanical properties iof sandwichs and its constituents
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Couanau, Quentin. "Ambiguity in dynamic contexts." Thesis, Paris 1, 2019. http://www.theses.fr/2019PA01E010.
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Cette thèse porte sur les conséquences de l’aversion à l’ambiguïté dans des contextes dynamiques en économie. En particulier, elle s’intéresse aux conséquences de l’aversion à l’ambiguïté dans les décisions d’investissement irréversibles, ainsi que dans un problème d’aléa moral dynamique, modélisé en temps continu. Le premier chapitre propose une revue de la littérature traitant de l’aversion à l’ambiguïté en contexte dynamique. Nous y passons en revue les modèles existants ainsi que leurs applications en économie et en finance. Le second chapitre s’intéresse aux décisions d’investissement irréversible d’un monopole et de firmes en compétition parfaite, en présence d’ambiguïté à propos de la volatilité du processus stochastique gouvernant la demande. Cette notion particulière d’ambiguïté nécessite de mobiliser les outils récents de la théorie des espérances non linéaires. On y montre qu’en présence d’aversion à l’ambiguïté, la stratégie optimale d’un monopole implique d’investir plus rapidement que dans un marché en concurrence parfaite. Le troisième chapitre s’appuie sur les résultats du second chapitre pour traiter le cas d’une concurrence imparfaite entre deux firmes. Le quatrième chapitre traite d’un problème d’aléa moral dynamique en temps continu et on y introduit la notion plus classique d’ambiguïté à propos de la dérive du processus gouvernant l’incertitude. On y montre que sous certaines restrictions semblables au cas standard, le contrat optimal est linéaire par rapport à la production finale. Ce résultat nous permet ensuite de discuter l’effet de l’aversion à l’ambiguïté sur les incitations et l’utilisation de l’informationThis thesis focuses on the consequences of ambiguity aversion in dynamic contexts in economics. In particular, we focus on the consequences of ambiguity aversion in irreversible investment problems, and in dynamic moral hazard problems in continuous-time. The first chapter reviews the literature on ambiguity in dynamic contexts, and reviews existing models as well as their applications in economics and finance. The second chapter deals with irreversible investment in the monopoly case and under perfect competition, under ambiguous volatility. The notion of ambiguous volatility requires the use of recent tools in non linear expectation theory. We show that the optimal entry strategy of a monopoly under ambiguous volatility implies investing sooner than the perfectly competitive equilibrium under volatility ambiguity. The third chapter builds on the results of the second chapter and treats a special case of imperfect competition. The last chapter deals with a dynamic principal-agent problem under moral in continuous-time, in which agents perceive ambiguity about the drift of the relevant process. We show that under certain conditions, the optimal contract is linear in final output. We then use this result to discuss the effect of ambiguity aversion on the incentive power of the optimal contract and the informativeness principle
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Grillo, Federico William. "A window on the ageing brain : imaging synapses and their dynamics in vivo." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/14407.
Full textAbstract:
The ageing process has an enormous impact on the human body and it represents a major risk factor for a number of diseases. Ageing is also associated with a progressive cognitive decline mainly involving the memory domain. Up to date many studies have investigated the structural and functional changes that occur in the ageing brain. Rather than neuronal loss, it is now widely accepted that synaptic impairments underlie the decreased cognitive performance. Such studies point to reduced synaptic density and plasticity, in specific brain regions, during ageing. However, most studies so far made use of either post-mortem or ex vivo preparations. Thus, the key question addressed in this thesis is to what extent synaptic elements are dynamic in the intact aged brain. A combination of in vivo two-photon imaging, correlated two-photon-electron microscopy and novel computational tools was used to study synaptic boutons in the aged mouse somatosensory cortex. Unexpectedly, circuit-specific increased rates of bouton formation, elimination, and destabilization were found. Age related increased dynamics greatly affected large (i.e., strong) boutons, thought to encode long-term memory, as opposed to smaller ones. The rigorous measurement of the size and location of axonal boutons, achieved for the first time in vivo, showed that while the average density and size of boutons was not affected by ageing, bouton size changes were greater in the aged animals. Such increased size fluctuations were again confined to larger, persistent boutons., Long-term memory impairment, as assessed in a novel behavioural task, was therefore associated with increased, rather than decreased, synaptic destabilization and dynamics, suggesting the existence of a novel mechanism underlying age related cognitive decline.
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Dalle, Pezze Piero. "Dynamical models of the mammalian target of rapamycin network in ageing." Thesis, University of Newcastle upon Tyne, 2013. http://hdl.handle.net/10443/2183.
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The mammalian Target of Rapamycin (mTOR)kinase is a central regulator of cellular growth and metabolism and plays an important role in ageing and age- related diseases. The increase of invitro data collected to extend our knowledge on its regulation, and consequently improve drug intervention,has highlighted the complexity of the mTOR network. This complexity is also aggravated by the intrinsic time-dependent nature of cellular regulatory network cross-talks and feedbacks. Systems biology constitutes a powerful tool for mathematically for- malising biological networks and investigating such dynamical properties. The present work discusses the development of three dynamical models of the mTOR network. The first aimed at the analysis of the current literature-based hypotheses of mTOR Complex2(mTORC2)regulation. For each hypothesis, the model predicted specific differential dynamics which were systematically tested by invitro experiments. Surprisingly, nocurrent hypothesis could explain the data and a new hypothesis of mTORC2 activation was proposed. The second model extended the previous one with an AMPK module. In this study AMPK was reported to be activated by insulin. Using a hypothesis ranking approach based on model goodness-of-fit, AMPK activity was insilico predicted and in vitro tested to be activated by the insulin receptor substrate(IRS).Finally,the last model linked mTOR with the oxidative stress response, mitochondrial reg- ulation, DNA damage and FoxO transcription factors. This work provided the characterisation of a dynamical mechanism to explain the state transition from normal to senescent cells and their reversibility of the senescentphenotype.
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Fletcher, Martyn. "An agent-based approach to dynamic network management." Thesis, Keele University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363754.
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Ladi, Anna. "Adaptive chemical agent detection in dynamic, changing environments." Thesis, University of York, 2015. http://etheses.whiterose.ac.uk/12692/.
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In this thesis a framework for adaptive chemical detection is developed, considering the application scenario of autonomous, robot mounted chemical agent detection in dynamic, changing environments. Chemical detection is performed by the Receptor Density Algorithm (RDA), a previously developed immune-inspired anomaly detection algorithm, which suffers from a decrease in its performance when the background environment changes. Focusing on the software part of the system, the goal of this thesis is to adapt the RDA quickly and autonomously, without requiring user feedback. The approach adopted is to first detect a change in the background data generating distribution, also defined as concept drift, and adapt in response to this detected change. Statistical hypothesis testing is used to determine whether there has been concept drift in consecutive time windows of the incoming sensor data. Five different statistical methods are tested on mass spectrometry data, enhanced with artificial concept drift that signifies a changing environment. The results show that, while no one method is universally best, statistical hypothesis testing can detect concept drift in the context of chemical sensing and it can differentiate between anomalies and concept drift. The adaptation of the system, which is triggered by the detection of concept drift, is achieved by switching to an ensemble (a set) of RDAs , created from a pool of pre-existing candidates. A novel mechanism for evaluating and selecting the members of the ensemble from this pool is proposed; it uses implicit performance information, extracted from the dynamics of the RDA, and does not require new user input to evaluate the candidates for the new environment. An ensemble of 5 members, selected in this way is found to be significantly better than a single RDA, the previously known best, reducing both the false detections and the number of missed anomalies. This method for selecting the ensemble members is also found significantly better than populating the ensemble based on their performance of the environment before concept drift. Finally, it is found that the ensemble can be created online, with its performance converging to the offline variant.
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Macarthur, Kathryn. "Multi-agent coordination for dynamic decentralised task allocation." Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/209737/.
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Coordination of multiple agents for dynamic task allocation is an important and challenging problem, which involves deciding how to assign a set of agents to a set of tasks, both of which may change over time (i.e., it is a dynamic environment). Moreover, it is often necessary for heterogeneous agents to form teams to complete certain tasks in the environment. In these teams, agents can often complete tasks more efficiently or accurately, as a result of their synergistic abilities. In this thesis we view these dynamic task allocation problems as a multi-agent system and investigate coordination techniques for such systems. In more detail, we focus specially on the distributed constraint optimisation problem (DCOP) formalism as our coordination technique. Now, a DCOP consists of agents, variables and functions agents must work together to find the optimal configuration of variable values. Given its ubiquity, a number of decentralised algorithms for solving such problems exist, including DPOP, ADOPT, and the GDL family of algorithms. In this thesis, we examine the anatomy of the above-mentioned DCOP algorithms and highlight their shortcomings with regard to their application to dynamic task allocation scenarios. We then explain why the max-sum algorithm (a member of the GDL family) is the most appropriate for our setting, and define specific requirements for performing multi-agent coordination in a dynamic task allocation scenario: namely, scalability, robustness, efficiency in communication, adaptiveness, solution quality, and boundedness. In particular, we present three dynamic task allocation algorithms: fast-max-sum, branchand-bound fast-max-sum and bounded fast-max-sum, which build on the basic max-sum algorithm. The former introduces storage and decision rules at each agent to reduce overheads incurred by re-running the algorithm every time the environment changes. However, the overall computational complexity of fast-max-sum is exponential in the number of agents that could complete a task in the environment. Hence, in branchand- bound fast-max-sum, we give fast-max-sum significant new capabilities: namely, an online pruning procedure that simplifies the problem, and a branch-and-bound technique that reduces the search space. This allows us to scale to problems with hundreds of tasks and agents, at the expense of additional storage. Despite this, fast-max-sum is only proven to converge to an optimal solution on instances where the underlying graph contains no cycles. In contrast, bounded fast-max-sum builds on techniques found in bounded max-sum, another extension of max-sum, to find bounded approximate solutions on arbitrary graphs. Given such a graph, bounded fast-max-sum will run our iGHS algorithm, which computes a maximum spanning tree on subsections of a graph, in order to reduce overheads when there is a change in the environment. Bounded fast-max-sum will then run fast-max-sum on this maximum spanning tree in order to find a solution. We have found that fast-max-sum reduces the size of messages communicated and the amount of computation by up to 99% compared with the original max-sum. We also found that, even in large environments, branch-and-bound fast-max-sum finds a solution using 99% less computation and up to 58% fewer messages than fast-max-sum. Finally, we found bounded fast-max-sum reduces the communication and computation cost of bounded max-sum by up to 99%, while obtaining 60{88% of the optimal utility, at the expense of needing additional communication than using fast-max-sum alone. Thus, fast-max-sum or branch-and-bound fast-max-sum should be used where communication is expensive and provable solution quality is not necessary, and bounded fast-max-sum where communication is less expensive, and provable solution quality is required. Now, in order to achieve such improvements over max-sum, fast-max-sum exploits a particularly expressive model of the environment by modelling tasks in the environment as function nodes in a factor graph, which need to have some communication and computation performed for them. An equivalent problem to this can be found in operations research, and is known as scheduling jobs on unrelated parallel machines (also known as RjjCmax). In this thesis, we draw parallels between unrelated parallel machine scheduling and the computation distribution problem, and, in so doing, we present the spanning tree decentralised task distribution algorithm (ST-DTDA), the first decentralised solution to RjjCmax. Empirical evaluation of a number of heuristics for ST-DTDA shows solution quality achieved is up to 90% of the optimal on sparse graphs, in the best case, whilst worst-case quality bounds can be estimated within 5% of the solution found, in the best case
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Meyer, David, and Christian Buchta. "SIMENV: A dynamic simulation environment for heterogeneous agents." SFB Adaptive Information Systems and Modelling in Economics and Management Science, WU Vienna University of Economics and Business, 2003. http://epub.wu.ac.at/1102/1/document.pdf.
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We introduce a generic simulation framework suitable for agent-based simulations featuring the support of heterogeneous agents, hierarchical scheduling, and flexible specification of design parameters. One key aspect of this framework is the design specification: we use a format based on the Extensible Markup Language (XML) that is simple-structured yet still enables the design of flexible models, with the possibility of varying both agent population and parameterization. Further, the tool allows the defi- nition of communication channels to single or groups of agents, and handles the information exchange. Also, both (groups of) agents and communications channels can be added and removed at runtime by the agents, thus allowing dynamic settings with the agent population and/or communication structures varying during the simulation time. A second issue in agent-based simulations, especially when readymade components are used, is the heterogeneity arising from both the agents' implementations and the underlying platforms: for this, we introduce a wrapper technique for mapping the functionality of agents living in an interpreter-based environment to a standardized JAVA interface, thus facilitating the task for any control mechanism (like a simulation manager). Again, this mapping is made by an XML-based definition format. (author's abstract)Series: Working Papers SFB "Adaptive Information Systems and Modelling in Economics and Management Science"
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Heideman, Simone. "Dynamics of temporal anticipation in perception and action." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:98dde64e-11ea-4516-af8c-5f4707d52907.
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The selective deployment of attention over time optimises our perception and action at the moments when relevant events are expected to happen. Such "temporal orienting" to moments when something is going to happen is especially useful when this information can be combined with predictions about where and what events are likely to occur. A large body of research has already established how temporal predictions dynamically influence our perception and action, but questions remain regarding the neural bases of these attentional mechanisms. In this thesis I present three magnetoencephalography (MEG) studies that I conducted to investigate anticipatory neural dynamics associated with spatial-temporal orienting of attention for perception and action. I also investigate and discuss how such anticipatory dynamics change with ageing and neurodegeneration in Parkinson's disease (PD), and how these anticipatory neural dynamics behave in situations where a complex, hidden spatial-temporal structure is present. In Chapter 1, I introduce the topic of this thesis by reviewing the literature on temporal orienting of attention and by introducing my specific research questions. In Chapter 2, I present an MEG study on anticipatory neural dynamics of joint spatial-temporal orienting of attention in the visual domain, in younger and older adults. This study shows that neural dynamics with spatial, temporal and spatial-temporal orienting are all differentially affected by ageing. In Chapter 3, I describe an MEG experiment that investigates anticipatory neural dynamics during spatial-temporal motor preparation and compares PD participants to healthy control participants. This study reveals that both behavioural and neural dynamics with temporal orienting are affected in PD. In Chapter 4, I describe an experiment that explores how an implicit spatial-temporal structure is utilised to predict and prepare for upcoming actions. This study shows that motor cortical excitability is dynamically modulated in anticipation of the location and timing of events, even when such expectations are hidden in complex visual-motor sequences that remain largely implicit. In Chapter 5, the General discussion, I place these results in their wider context and discuss limitations and future directions.
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Unrath, Craig S. "Dynamic exploration of helicopter reconnaissance through agent-based modeling." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA383393.
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Thesis (M.S. in Modeling, Virtual Environments and Simulation (MOVES))--Naval Postgraduate School, Sept. 2000.Thesis advisor(s): Gaver, Donald ; Hiles, John ; Jacobs, Patricia A. "September 2000." Includes bibliographical references (p. 109-110). Also available in print.
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Erdogdu, Utku. "Resource Based Plan Revision In Dynamic Multi-agent Systems." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12604721/index.pdf.
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Planning framework is commonly used to represent intelligent agents effectively and to model complex behavior. In planning framework, resource-based perspective is interesting in the sense that in a multi-agent environment, exchange of resources can form a cooperative interaction.
In resource based plan coordination, each agent constructs an individual plan, then plans are examined by a central plan revision unit for possibilities of removing actions.
Domain of this work is the classical postmen domain that is also modifed to have non-sub-additive property.The domain is has numerous challenges that is not considered in the original plan coordination model. Moreover, the plan coordination algorithm is used in the re-planning phase, as the environment changes through plan execution.These issues are common for the realistic environments and the details of the original plan coordination perspective are renewed to cope with these issues.
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Zhang, Yan-Mei. "Mobile-agent-based dynamic channel allocation with waiting queue." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0023/MQ50914.pdf.
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Zhang, Yan-Mei 1970. "Mobile-agent-based dynamic channel allocation with waiting queue." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21669.
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The explosive growth of the wireless users requires efficient channel utilization. In this thesis, we present a new channel allocation strategy with waiting queue model instead of the block-and-clear model so that the quality of service in cellular network can be improved.From a computational and network resource viewpoint, our model is based on the Mobile Agent Paradigm that has great advantages on reducing network traffic and dynamic adaptation. We also show the possibility to implement our algorithm on the Grasshopper mobile agent environment, which is compliant to the MASIF standard.
In order to evaluate the performance of our proposed model, a simulator is written in Java, which shows that our algorithm gives the lowest average blocking probability under different traffic load comparing with LP Scheme, First Available DCA Scheme and Simple FCA Scheme. Specifically, our algorithm has a tremendous capability of alleviating congestion in the hot spots of a cellular system.
Our research has been done within the group on "Advanced Studies on Mobile Environments" (ASME) as a part of the Consortium MIAMI (Mobile Intelligent Agents for Managing the Information Infrastructure).
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Back, David N. "Agent-based soldier behavior in dynamic 3D virtual environments." Thesis, Monterey, California. Naval Postgraduate School, 2002. http://hdl.handle.net/10945/6095.
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Human behavior in virtual environments is commonly implemented as a finite state machine. This programming approach can be effective and challenging against human players, but its ability to realistically simulate the behavior of cooperative groups of soldiers is limited. This thesis covers the development of an agent-based system to control the behavior of infantry in 3D virtual environments. The system design divides the cognitive process into four modules: perception, mental model, goal, decision, and action resolution. Each module attempts to simulate both strengths and weaknesses of human perception and cognition, including instinctive reactions, perceptual error, memory degradation, context-dependent decision-making, and inference. Additionally, the soldiers are influenced by the actions and decisions of the agents around them, enabling cooperation. The resultant agent system was incorporated into a game-like interface and compared to a similar commercial game with standard AI. Overall, 72% of the test subjects thought that the agent behaviors were Mostly Realistic or Totally Realistic, and 81% found them to be equal to or better than those in the commercial game.
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Redding, Joshua David 1978. "Approximate multi-agent planning in dynamic and uncertain environments." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/71456.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, February 2012."December 2011." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 120-131).
Teams of autonomous mobile robotic agents will play an important role in the future of robotics. Efficient coordination of these agents within large, cooperative teams is an important characteristic of any system utilizing multiple autonomous vehicles. Applications of such a cooperative technology stretch beyond multi-robot systems to include satellite formations, networked systems, traffic flow, and many others. The diversity of capabilities offered by a team, as opposed to an individual, has attracted the attention of both researchers and practitioners in part due to the associated challenges such as the combinatorial nature of joint action selection among interdependent agents. This thesis aims to address the issues of the issues of scalability and adaptability within teams of such inter-dependent agents while planning, coordinating, and learning in a decentralized environment. In doing so, the first focus is the integration of learning and adaptation algorithms into a multi-agent planning architecture to enable online adaptation of planner parameters. A second focus is the development of approximation algorithms to reduce the computational complexity of decentralized multi-agent planning methods. Such a reduction improves problem scalability and ultimately enables much larger robot teams. Finally, we are interested in implementing these algorithms in meaningful, real-world scenarios. As robots and unmanned systems continue to advance technologically, enabling a self-awareness as to their physical state of health will become critical. In this context, the architecture and algorithms developed in this thesis are implemented in both hardware and software flight experiments under a class of cooperative multi-agent systems we call persistent health management scenarios.
by Joshua David Redding.
Ph.D.
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Valenti, Mario J. (Mario James) 1976. "Approximate dynamic programming with applications in multi-agent systems." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40330.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
MIT Institute Archives copy: contains CDROM of thesis in .pdf format.
Includes bibliographical references (p. 151-161).
This thesis presents the development and implementation of approximate dynamic programming methods used to manage multi-agent systems. The purpose of this thesis is to develop an architectural framework and theoretical methods that enable an autonomous mission system to manage real-time multi-agent operations. To meet this goal, we begin by discussing aspects of the real-time multi-agent mission problem. Next, we formulate this problem as a Markov Decision Process (MDP) and present a system architecture designed to improve mission-level functional reliability through system self-awareness and adaptive mission planning. Since most multi-agent mission problems are computationally difficult to solve in real-time, approximation techniques are needed to find policies for these large-scale problems. Thus, we have developed theoretical methods used to find feasible solutions to large-scale optimization problems. More specifically, we investigate methods designed to automatically generate an approximation to the cost-to-go function using basis functions for a given MDP. Next, these these techniques are used by an autonomous mission system to manage multi-agent mission scenarios. Simulation results using these methods are provided for a large-scale mission problem. In addition, this thesis presents the implementation of techniques used to manage autonomous unmanned aerial vehicles (UAVs) performing persistent surveillance operations. We present an indoor multi-vehicle testbed called RAVEN (Real-time indoor Autonomous Vehicle test ENvironment) that was developed to study long-duration missions in a controlled environment.
(cont.) The RAVEN's design allows researchers to focus on high-level tasks by autonomously managing the platform's realistic air and ground vehicles during multi-vehicle operations, thus promoting the rapid prototyping of UAV technologies by flight testing new vehicle configurations and algorithms without redesigning vehicle hardware. Finally, using the RAVEN, we present flight test results from autonomous, extended mission tests using the technologies developed in this thesis. Flight results from a 24 hr, fully-autonomous air vehicle flight-recharge test and an autonomous, multi-vehicle extended mission test using small, electric-powered air vehicles are provided.
by Mario J. Valenti.
Ph.D.
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Xu, Zhi-Hui 1976. "Generic exception analysis in a dynamic multi-agent environment." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/86568.
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Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.Includes bibliographical references (leaves 45-46).
by Zhi-Hui (Winifred) Xu.
S.B.and M.Eng.
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Erdoğdu, Utku. "Resource based plan revision in dynamic multi-agent environments." Ankara : METU, 2004. http://etd.lib.metu.edu.tr/upload/12604721/index.pdf.
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Shan, Yaping. "Essays on dynamic contracts." Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/3534.
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This dissertation analyzes the contracting problem between a firm and the research employees in its R&D department. The dissertation consists of two chapters. The first chapter addresses a simplified problem in which the R&D unit has only one agent. The second chapter studies a scenario in which the R&D unit consists of a team.
In the first chapter, I look at problem in which a principal hires an agent to do a multi-stage R&D project. The transition from one stage to the next is modeled by a Poisson-type process, whose arrival rate depends on the agents choice of effort. I assume that effort choice is binary and unobservable by the principal. To overcome the repeated moral-hazard problem, the principal offers the agent a long-term contract which specifies a flow of payments based on his observation of the outcome of the project. The optimal contract combines rewards and punishments: the payment to the agent decrease over time in case of failure and jumps up to a higher level after each success. I also show that the optimal contract can be implemented by using a risky security that has some of the features of the stocks of these firms, thereby providing a theoretical justification for the wide-spread use of stock-based compensation in firms that rely on R&D.
In the second chapter, I look at a scenario in which the R&D unit consists of a team, which I assume, for simplicity, comprises two risk-averse agents. Now, the Poisson arrival rate is jointly determined by the actions of both agents with the action of each remaining unobservable by both the principal and the other agent. I assume that when success in a phase occurs the principal can identify the agent who was responsible for it. In this model, incentive compatibility means that each agent is willing to exert effort conditional on his coworker putting in effort, and thus exerting effort continuously is a Nash-equilibrium strategy played by the agents. In this multiagent problem, each agents payment depends not only on his own performance, but is affected by the other agents performance as well. Similar to the single-agent case, an agent is rewarded when he succeeds, and his payment decreases over time when both agents fail. Regarding how an agents payment relates to his coworkers performance, I find that the optimal incentive regime is a function of the way in which agents efforts interact with one another: relative-performance evaluation is used when their efforts are substitutes whereas joint-performance evaluation is used when their efforts are complements. This result sheds new light on the notion of optimal incentive regimes, an issue that has been widely discussed in multi-agent incentive problems.
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Muñoz, Moreno Israel. "Studies of dynamics of physical agent ecosystems." Doctoral thesis, Universitat de Girona, 2002. http://hdl.handle.net/10803/7717.
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This thesis addresses the problem of learning in physical heterogeneous multi-agent systems(MAS) and the analysis of the benefits of using heterogeneous MAS with respect to
homogeneous ones. An algorithm is developed for this task; building on a previous work on stability in distributed systems by Tad Hogg and Bernardo Huberman, and combining two phenomena observed in natural systems, task partition and hierarchical dominance. This algorithm is devised for allowing agents to learn which are the best tasks to perform on the basis of each agent's skills and the contribution to the team global performance. Agents learn by interacting with the environment and other teammates, and get rewards from the result of the actions they perform. This algorithm is specially designed for problems where all robots have to co-operate and work simultaneously towards the same goal. One example of such a problem is role distribution in a team of heterogeneous robots that form a soccer team, where all members take decisions and co-operate simultaneously. Soccer offers the possibility of conducting research in MAS, where co-operation plays a very important role in a dynamical and changing environment. For these reasons and the experience of the University of Girona in this domain, soccer has been selected as the test-bed for this research. In the case of soccer, tasks are grouped by means of roles.
One of the most interesting features of this algorithm is that it endows MAS with a high
adaptability to changes in the environment. It allows the team to perform their tasks, while
adapting to the environment. This is studied in several cases, for changes in the environment and in the robot's body. Other features are also analysed, especially a parameter that defines the fitness (biological concept) of each agent in the system, which contributes to performance and team adaptability.
The algorithm is applied later to allow agents to learn in teams of homogeneous and
heterogeneous robots which roles they have to select, in order to maximise team performance. The teams are compared and the performance is evaluated in the games against three hand-coded teams and against the different homogeneous and heterogeneous teams built in this thesis. This section focuses on the analysis of performance and task partition, in order to study the benefits of heterogeneity in physical MAS.
In order to study heterogeneity from a rigorous point of view, a diversity measure is developed building on the hierarchic social entropy defined by Tucker Balch. This is adapted to quantify physical diversity in robot teams. This tool presents very interesting features, as it can be used in the future to design heterogeneous teams on the basis of the knowledge on other teams.
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Waseda, Osamu. "Atomic scale investigation of ageing in metals." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI150/document.
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Selon la théorie de Cottrell et Bilby, les dislocations à travers leur champ de contrainte interagissent avec les atomes de soluté qui s’agrègent au cœur et autour des dislocations (atmosphère de Cottrell). Ces atmosphères « bloquent » les dislocations et fragilisent le matériau. Dans cette thèse, les techniques de simulations à l’échelle atomique telles que la Dynamique Moléculaire, les simulations Monte Carlo Cinétique, Monte Carlo Métropolis ont été développées qui permettent de prendre en compte les interactions entre plusieurs centaines d’atomes de carbone et la dislocation, pour étudier la cinétique de formation ainsi que la structure d’une atmosphère de Cottrell. Par ailleurs, la technique de simulation est appliquée à deux autres problématiques: premièrement, il est connu que les atomes de C dans la ferrite se mettent en ordre (mise en ordre de Zener). La stabilité de cette phase est étudiée en fonction de la température et la concentration de C. Deuxièmement, la ségrégation des atomes de soluté dans les nano-cristaux de Ni ainsi que la stabilité des nano-cristaux avec les atomes de soluté dans les joints de grain à haute température est étudiéeThe objective of the thesis was to understand the microscopic features at the origin of ageing in metals. The originality of this contribution was the com- bination of three complementary computational techniques : (1) Metropolis Monte Carlo (MMC), (2) Atomic Kinetic Monte Carlo (AKMC), and, (3) Molecular Dynamics (MD). It consisted of four main sections : Firstly the ordering occurring in bulk alpha-iron via MMC and MD was studied. Various carbon contents and temperatures were investigated in order to obtain a “phase diagram”. Secondly, the generation of systems containing a dislocation interacting with many carbon atoms, namely a Cottrell Atmosphere, with MMC technique was described. The equilibrium structure of the atmosphere and the stress field around the atmospheres proves that the stress field around the dislocation was affected but not cancelled out by the atmosphere. Thirdly, the kinetics of the carbon migration and Cottrell atmosphere evolution were investigated via AKMC. The activation energies for carbon atom migration were calculated from the local stress field and the arrangement of the neigh- bouring carbon atoms. Lastly, an application of the combined use of MMC and MD to describe grain boundary segregation of solute atoms in fcc nickel was presented. The grain growth was inhibited due to the solute atoms in the grain boundary
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Dannenhauer, Zohreh A. "Anticipation in Dynamic Environments: Deciding What to Monitor." Wright State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=wright1559307835737411.
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Shahnewaz, Farhan. "ON PERFORMANCE OF DYNAMIC NETWORK ORGANIZATIONS." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1384.
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In this paper we have introduced a concept of analyzing the performance of dynamic network organization (NO) in response to multiple input objectives of network organization (NO) and input set of unpredictable external environment, and we have correlated plasticity of NO with this performance measure. A three stage conceptual model of the process has been described which comprised of dynamic system of multi-agent network, multiple objectives and input goals of network driver (S n), unpredictable external environment (ϵ). Dynamic system of the network organization takes through its two phase and processes this based on time and system response variables. Processing of input information by the system variables gives a ratio of system response variable and input. Further analysis is based on the value of this performance values. This model suggests a performance measuring technique which takes an input set of objectives from network driver of the NO, a set of input from external environment (ϵ) state and processes this input based on the existing state of the dynamic system in the NO. This process output shows dynamic system performance in dynamic environment and how this performance coefficient correlates with the Plasticity of network organization. We have presented several examples, mathematical models and graph by analyzing true scenarios on UAV patrolling zone.