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1
Moreira, Evaldinólia Gilbertoni. "Dynamic coupling of multiscale land change models." Instituto Nacional de Pesquisas Espaciais, 2009. http://urlib.net/sid.inpe.br/mtc-m18@80/2008/11.10.16.23.
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Mudanças terrestres são resultados de uma complexa rede de interações entre fatores humanos e biofísicos, que atuam em diferentes escalas temporais e espaciais. Entender estes processos de mudanças terrestres de escalas locais a globais e seus impactos no sistema acoplado homem-natureza é um enorme desafio científico. Modelos em uma única escala podem não ser capazes capturar tais interações e processos de mudança. Esta tese apresenta uma metodologia para a construção de modelos de mudanças terrestre multiescala e multilocalidade, incluindo interações top-down e bottom-up. Numa primeira etapa, conceituamos dois tipos de relações espaciais entre objetos geográficos em diferentes escalas. Relações hierárquicas são propostas para tratar das interações entre objetos espacialmente aninhados, e relações de "ação à distância" são propostas para tratar de interações entre redes e objetos espaciais. Então, numa segunda etapa, apresentamos uma proposta de organização modular do software dos modelos. Consideramos neste trabalho o caso onde modelos para cada escala são independentemente construídos, possivelmente com abordagens distintas, e então dinamicamente acoplados. Conceitos de acopladores de modelos são introduzidos para definir o fluxo de informação bidirecional entre escalas. Estes conceitos foram implementado no ambiente de modelagem TerraME. Como prova de conceito, apresentamos um exemplo com duas escalas hierárquicas para Amazônia Brasileira. A conclusão deste trabalho aponta que a combinação de relações espaciais hierárquicas com relações baseadas em redes provê um arcabouço conceitual abrangente para lidar com interações top-down e bottom-up em modelos multiescala de mudanças terrestres. A organização modular e o conceito de acopladores propostos são bastante genéricos para serem usados com outros tipos de aplicação, e com isso contribuir para criação de modelos ambientais integrados, considerando escalas locais a globais.Land changes are the result of a complex web of interactions between human and biophysical factors, which act over a wide range of temporal and spatial scales. Understanding processes of change from local to global scale and their impacts on the coupled human-environmental system is a main scientific challenge. No single model or scale can fully capture such interactions and processes of land change. This thesis presents a methodology for building multiscale, multi-locality land change models that include top-down and bottom-up relations. At first, we conceptualize two types of spatial relations among geographic objects at different scales. To handle the interaction of nested spatial objects at different scales, we propose hierarchical relations. To handle the interaction between networks and spatial objects, we propose action-at-a-distance relations. Then in a second step, we propose a modular software organization to build multiscale land change models. We consider the case when single-scale models, using different modeling approaches, are independently built and then dynamically coupled. We introduce the concepts of Model Couplers to define the bi-directional flow of information between the scales. We implement these concepts using the TerraME modeling environment. As a proof of concept, we present a hierarchical two-scale example for the Brazilian Amazon. The conclusion of this work points out that combining hierarchical and network-based spatial relations provides a comprehensive conceptual framework to include top-down and bottom-up interactions and feedbacks in multi-scale land-change models. The modular software organization and concept of Model Couplers are general enough to be used for other types of applications, and to contribute to the creation of Integrated Environmental Models from local to global scales.
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Zeileis, Achim, Friedrich Leisch, Christian Kleiber, and Kurt Hornik. "Monitoring structural change in dynamic econometric models." SFB Adaptive Information Systems and Modelling in Economics and Management Science, WU Vienna University of Economics and Business, 2002. http://epub.wu.ac.at/1296/1/document.pdf.
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The classical approach to testing for structural change employs retrospective tests using a historical data set of a given length. Here we consider a wide array of fluctuation-type tests in a monitoring situation - given a history period for which a regression relationship is known to be stable, we test whether incoming data are consistent with the previously established relationship. Procedures based on estimates of the regression coefficients are extended in three directions: we introduce (a) procedures based on OLS residuals, (b) rescaled statistics and (c) alternative asymptotic boundaries. Compared to the existing tests our extensions offer better power against certain alternatives, improved size in finite samples for dynamic models and ease of computation respectively. We apply our methods to two data sets, German M1 money demand and U.S. labor productivity.Series: Report Series SFB "Adaptive Information Systems and Modelling in Economics and Management Science"
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Barth, Volker. "Integrated assessment of climate change using structural dynamic models." Hamburg : Max-Planck-Inst. für Meteorologie, 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968535933.
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Wu, Ning. "Artificial intelligence solutions for models of dynamic land use change." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610781.
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Wiener, Karl Kilian Konrad, and n/a. "DYNAMIC CHANGE PROCESS: HOW DO COGNITIVE READINESS DRIVERS INFORM CHANGE AGENTS ON EMPLOYEE BEHAVIOURAL CHANGE INTENTION." University of Canberra. n/a, 2008. http://erl.canberra.edu.au./public/adt-AUC20081217.120215.
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It is well accepted by now that most change initiatives are unsuccessful even though more
organisations are experiencing change as they fight to retain and improve their
competitiveness in the market place. It is against this background of change failure that
researchers have looked for new strategies to improve change outcomes. Theoretical
models conceptualising the dynamic change process advise on better change strategies, but
little empirical evidence has demonstrated that these models are effective in improving
change implementation outcomes. Theoretical models were also developed to counter
change resistance, but little emphasis has been placed on employee change readiness.
Some empirical research on employee change readiness explores employees? perception of
organisational readiness, but no empirical research has explored employee readiness from a
psychological perspective. That is, how to create change readiness in employees.
This thesis has contributed to both the theoretical and empirical understanding of the
change readiness model. Firstly, the theoretical readiness for change model Armenakis et
al.?s (1993, 2002) was extended by the inclusion of the ?understanding of the change?
driver. Secondly, this change readiness model was empirically tested on two distinct
organisational changes: organisational restructure and IT change. The extended model is
also examined for two change stages of the dynamic process to identify which readiness
drivers should be prioritised by change agents.
Two online questionnaires were administered eight months apart assessing the responses to
three change stages (planning, implementation and post-implementation) of employees ?
supervisors and subordinates - of a flat structured organisation in the human resource
industry. At the two measurement points 189 and 141 employees returned completed
surveys. Six employee readiness drivers were operationalised and regressed against
behavioural change intention.
The quantitative findings using regression models across two change types and
longitudinally did not identify a specific change pattern. However, all six readiness drivers
including the ?understanding of the change? driver were influential on employees?
behavioural change intention. Furthermore, statistical differences between supervisors and
subordinates were identified in the organisational restructure change.
The quantitative findings using a triangulation approach with qualitative date including
data from two unstructured interviews and employee comments further validated the
quantitative findings. The thematic analysis of the employee comments enhanced the
findings and identified employee specific concerns including information dissemination of
the changes and a level of uncertainty.
The findings supported Armenakis et al.?s (1993, 2002) theoretical contribution that
change readiness drivers are an important part of the organisational change process
explaining why employee do and do not change. The empirical application of readiness
change driver evaluation during the dynamic change is supported as it permits change
agents to directly monitor employees? readiness perception of a specific change target.
This valuable information finds practical utilisation for change agents in providing targeted
guidance and support for employees thus facilitating a greater likelihood of a positive
change outcome.
Implications of these findings and future research opportunities are discussed.
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Zurell, Damaris. "Integrating dynamic and statistical modelling approaches in order to improve predictions for scenarios of environmental change." Phd thesis, Universität Potsdam, 2011. http://opus.kobv.de/ubp/volltexte/2011/5684/.
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Species respond to environmental change by dynamically adjusting their geographical ranges. Robust predictions of these changes are prerequisites to inform dynamic and sustainable conservation strategies. Correlative species distribution models (SDMs) relate species’ occurrence records to prevailing environmental factors to describe the environmental niche. They have been widely applied in global change context as they have comparably low data requirements and allow for rapid assessments of potential future species’ distributions. However, due to their static nature, transient responses to environmental change are essentially ignored in SDMs. Furthermore, neither dispersal nor demographic processes and biotic interactions are explicitly incorporated. Therefore, it has often been suggested to link statistical and mechanistic modelling approaches in order to make more realistic predictions of species’ distributions for scenarios of environmental change.
In this thesis, I present two different ways of such linkage. (i) Mechanistic modelling can act as virtual playground for testing statistical models and allows extensive exploration of specific questions. I promote this ‘virtual ecologist’ approach as a powerful evaluation framework for testing sampling protocols, analyses and modelling tools. Also, I employ such an approach to systematically assess the effects of transient dynamics and ecological properties and processes on the prediction accuracy of SDMs for climate change projections. That way, relevant mechanisms are identified that shape the species’ response to altered environmental conditions and which should hence be considered when trying to project species’ distribution through time. (ii) I supplement SDM projections of potential future habitat for black grouse in Switzerland with an individual-based population model. By explicitly considering complex interactions between habitat availability and demographic processes, this allows for a more direct assessment of expected population response to environmental change and associated extinction risks. However, predictions were highly variable across simulations emphasising the need for principal evaluation tools like sensitivity analysis to assess uncertainty and robustness in dynamic range predictions. Furthermore, I identify data coverage of the environmental niche as a likely cause for contrasted range predictions between SDM algorithms. SDMs may fail to make reliable predictions for truncated and edge niches, meaning that portions of the niche are not represented in the data or niche edges coincide with data limits.
Overall, my thesis contributes to an improved understanding of uncertainty factors in predictions of range dynamics and presents ways how to deal with these. Finally I provide preliminary guidelines for predictive modelling of dynamic species’ response to environmental change, identify key challenges for future research and discuss emerging developments.Das Vorkommen von Arten wird zunehmend bedroht durch Klima- und Landnutzungswandel. Robuste Vorhersagen der damit verbundenen Arealveränderungen sind ausschlaggebend für die Erarbeitung dynamischer und nachhaltiger Naturschutzstrategien. Habitateignungsmodelle erstellen statistische Zusammenhänge zwischen dem Vorkommen einer Art und relevanten Umweltvariablen und erlauben zügige Einschätzungen potentieller Arealveränderungen. Dabei werden jedoch transiente Dynamiken weitgehend ignoriert sowie demographische Prozesse und biotische Interaktionen. Daher wurden Vorschläge laut, diese statistischen Modelle mit mechanistischeren Ansätzen zu koppeln. In der vorliegenden Arbeit zeige ich zwei verschiedene Möglichkeiten solcher Kopplung auf. (i) Ich beschreibe den sogenannten ‚Virtuellen Ökologen’-Ansatz als mächtiges Validierungswerkzeug, in dem mechanistische Modelle virtuelle Testflächen bieten zur Erforschung verschiedener Probenahmedesigns oder statistischer Methoden sowie spezifischer Fragestellungen. Auch verwende ich diesen Ansatz, um systematisch zu untersuchen wie sich transiente Dynamiken sowie Arteigenschaften und ökologische Prozesse auf die Vorhersagegüte von Habitateignungsmodellen auswirken. So kann ich entscheidende Prozesse identifizieren welche in zukünftigen Modellen Berücksichtigung finden sollten. (ii) Darauf aufbauend koppele ich Vorhersagen von Habitateignungsmodellen mit einem individuen-basierten Populationsmodell, um die Entwicklung des Schweizer Birkhuhnbestandes unter Klimawandel vorherzusagen. Durch die explizite Berücksichtigung der Wechselwirkungen zwischen Habitat und demographischer Prozesse lassen sich direktere Aussagen über Populationsentwicklung und damit verbundener Extinktionsrisiken treffen. Allerdings führen verschiedene Simulationen auch zu hoher Variabilität zwischen Vorhersagen, was die Bedeutung von Sensitivitätsanalysen unterstreicht, um Unsicherheiten und Robustheit von Vorhersagen einzuschätzen. Außerdem identifiziere ich Restriktionen in der Datenabdeckung des Umweltraumes als möglichen Grund für kontrastierende Vorhersagen verschiedener Habitateignungsmodelle. Wenn die Nische einer Art nicht vollständig durch Daten beschrieben ist, kann dies zu unrealistischen Vorhersagen der Art-Habitat-Beziehung führen. Insgesamt trägt meine Arbeit erheblich bei zu einem besseren Verständnis der Auswirkung verschiedenster Unsicherheitsfaktoren auf Vorhersagen von Arealveränderungen und zeigt Wege auf, mit diesen umzugehen. Abschließend erstelle ich einen vorläufigen Leitfaden für Vorhersagemodelle und identifiziere Kernpunkte für weitere Forschung auf diesem Gebiet.
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Barth, Volker [Verfasser]. "Integrated assessment of climate change using structural dynamic models / Max-Planck-Institut für Meteorologie. Von Volker Barth." Hamburg : Max-Planck-Inst. für Meteorologie, 2003. http://d-nb.info/968535933/34.
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Davis, Michael C. "Dynamic models of price changes /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2001. http://wwwlib.umi.com/cr/ucsd/fullcit?p3026374.
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Kasun, Matthew R. (Matthew Roger) Carleton University Dissertation Engineering Systems and computer. "A meta-model for dynamic change management." Ottawa, 1993.
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Juntunen, M. (Marko). "Business model change as a dynamic capability." Doctoral thesis, Oulun yliopisto, 2017. http://urn.fi/urn:isbn:9789526216621.
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Abstract The purpose of this study is to explore the role of dynamic capability in business model change in Internet-based business start-ups and Internet-based business enterprises. This study reviews the literature on business models, business model change, and dynamic capability, and defines business model change as a dynamic capability that is expected to lead to increased speed of business change and competitive advantages over the long term. This empirical study of business model change is accomplished by the case study method. The study is based on field data of four case companies regarding entrepreneurs’, business developers’, and business leaders’ behavior and actions while they are utilizing the business model concept for the purpose of business change. This study approaches business model change as a dynamic capability from three dynamic capability cluster perspectives. It explores how businesses can use the concept of business model for business decisions as well as how they can use the concept of business model to improve the speed of business change after new business opportunities or threats are found. The analysis identifies the process of business model change and factors that affect business model change, and the outcomes are results from three dynamic capability clusters that Internet-based companies are able to follow in a fast-changing business environment. This study develops a posteriori model proposing that a dynamically capable business model change consists of sensing, seizing, and transforming activities to obtain successful business and competitive advantages over the long term. A posteriori model of business model change as a dynamic capability creates a framework to support a quick business model change, especially in a fast-changing business environment. This study adds a dynamic capability viewpoint to the business model literature pertaining to business modeling and business model change. Regarding the managerial implications, this study shows how entrepreneurs and business owners can utilize the concept of business model in order to support a quick business change and possibly gain a competitive advantage in the long term. The study results indicate that internal and external factors for business model change are company-specific and those vary between the start-up and enterprise. And thus, a successful business model change can be achieved through analyzing and further developing these company-specific factors. These factors can be seen as a micro foundation of dynamic capability, and development of these factors can improve competitive advantageTiivistelmä Tässä tutkimuksessa tarkastellaan nuoreen Internet liiketoimintaan pohjautuvaan kasvuyritykseen ja kypsiin Internet liiketoimintaan pohjautuviin yrityksiin tehtyjä liiketoimintamallimuutoksia dynaamisten kyvykkyyksien näkökulmasta. Tutkimuksen aihetta lähestytään nuoren kasvuyrityksen sekä kypsien yritysten kannalta ja työn teoreettinen viitekehys rakennetaan liiketoimintamallin, liiketoimintamallimuutoksen sekä dynaamisen kyvykkyyden tutkimusjulkaisujen kautta. Työssä liiketoimintamallimuutos määritellään dynaamiseksi kyvykkyydeksi joka kehittyy eri toimintojen avulla. Tämä dynaaminen kyvykkyys voi mahdollistaa nopeamman liiketoimintamuutoksen ja pitkällä aikavälillä se voi vaikuttaa myös kilpailuedun saavuttamiseen. Työn empiirisessä osassa liiketoimintamallimuutosta tutkitaan tapaustutkimusmenetelmällä neljässä yrityksessä. Yrittäjien, liiketoimintakehittäjien, sekä johtajien käyttäytymistä ja toimenpiteitä tutkitaan liiketoimintamallikonseptin kautta muutostilanteessa. Yrittäjien, liiketoimintakehittäjien, sekä johtajien käyttäytymistä ja toimenpiteitä tutkitaan liiketoimintamallikonseptin kautta muutostilanteessa. Työssä dynaamista liiketoimintamallimuutosta lähestytään kolmen dynaamiselle kyvykkyydelle määritellyn klusterin kautta (havaitseminen, tarttuminen, sekä uhkien hallinta ja muuntautuminen). Nämä klusterit toimivat erityisesti silloin kun yritysten tulee tehdä nopeita liiketoimintapäätöksiä ja liiketoimintamuutoksia. Analyysissa tunnistetaan liiketoimintamallin muutosprosessi, sekä sisäiset ja ulkoiset tekijät joilla on vaikutusta liiketoimintamallimuutokseen. Lopputulokset ovat seuraus kolmesta dynaamisen ominaisuuden klusterista joita organisaatioiden tulisi huomioida nopeasti muuttuvassa ympäristössä. Tutkimuksessa kehitetään jälkikäteismalli jossa liiketoimintamallimuutos dynaamisena kyvykkyytenä synnytetään dynaamisen kyvykkyyden klustereissa esiintyvien toimenpiteiden kautta. Näiden toimenpiteiden avulla on mahdollista saavuttaa pitkällä aikavälillä menestystä ja mahdollisesti myös kilpailuetua. Jälkikäteismalli tukee dynaamista liiketoimintamallimuutosta nopeasti muuttuvassa liiketoimintaympäristössä. Työn teoreettinen kontribuutio on erityisesti dynaamisen kyvykkyyden näkökulma liiketoimintamallintamiseen ja liiketoimintamallimuutokseen. Työssä osoitetaan myös kuinka yrittäjät ja liiketoimintaomistajat voivat käytännössä hyödyntää liiketoimintamallikonseptia nopeasti tehtävään liiketoimintamuutokseen. Tutkimustulokset osoittavat, että sisäisillä ja ulkoisilla tekijöillä on vaikutusta liiketoimintamallimuutokseen. Nämä tekijät ovat yrityskohtaisia, ja nuoren kasvuyrityksen ja kypsien yritysten väliltä löytyy eroja. Sen vuoksi onnistunut liiketoimintamallimuutos voidaan tehdä näitä tekijöitä analysoimalla ja kehittämällä
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Rodriguez, Donaire Silvia. "Social media, interactive tools that change business model dynamics." Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/83599.
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The aim of this research is two-folded. On the one hand, it attempts to assist
employers of Catalan micro-retailers in designing, implementing and developing their
Social Media strategy as a complementary channel of communication. On the other
hand, it attempts to contribute to the research community with a better understanding
on both which building block of the micro-retailer¿s Business Model is more
influenced by the customer level of interaction by means of the Social Media and how
a transformation can be observed in the micro-retailers¿ Business Models as a result
of the Social Media implementation.
The research question to be answered in this paper is how the transformation of the
activity system of the micro-retailers¿ Business Model would allow the emergence of
a Participatory Business Model by means of Social Media. To carry out this research
the Participatory Action Research methodology was used, whose contribution has two
results: the one is more practitioner oriented and the other is more academic.
The incipient results of the research showed a scarce transformation of Catalan microretailer¿s
business model as a consequence of the implementation of social media.
However, it is significant enough to be considered as more than just a simple adoption
of an alternative channel of communication.
One of the main contributions is related to how customer influences the activity
system of the micro-retailer¿s business model beyond four levels of customer
interaction (communication, interaction, participation and collaboration) by means of
social media. On the one hand, the activity system of a business model is referred to
the eight building blocks of Osterwalder, Pigneur and Tucci (2005) research that
includes customer segment, customer relationship, distribution channel, capabilities,
partner, value configuration, value proposition, profit and cost. On the other hand, the
four defined levels of customer interaction are based on the literature of group
collaboration systems.
The results showed that not all the building blocks forming the business model are
influenced by consumer interaction. The only building blocks influenced by an initial
communication level in the current social media strategy implementation stage of our
sample (five micro-retailers) are the following: customer segment, customer
relationship, distribution channel, value proposition and cost. This incipient stage of
transformation can be justified by a lack of effort made due to the small size of the
business and a lack of team working inside the companies, easily adapting to changes.
It can also be justified by the fact it was carried out by the micro-retailers only during
a short period of time (14 month).
Another contribution of the paper shows that Social Media transformation drives a
BM innovation according to the following mediator elements: (1) the dynamic
capabilities, (2) the ability of learning, (3) the dedicated effort, (4) the implementation
time and (5) the level of customer participation.
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Westin, Lars. "Vintage models of spatial structural change." Doctoral thesis, Umeå universitet, Institutionen för nationalekonomi, 1990. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-73665.
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In the study a class of multisector network models, suitable for simulation of the interaction between production, demand, trade, and infrastructure, is presented. A characteristic feature of the class is a vintage model of the production system. Hence, the rigidities in existing capacities and the temporary monopolies obtainable from investments in new capacity at favourable locations are emphasized.As special cases, the class contains models in the modelling traditions of "interregional computable general equilibriunT, Hspatial price equilibrium**, "interregional input-output" and transportation networks.On the demand side, a multihousehold spatial linear expenditure system is introduced. This allows for an endogenous representation of income effects of skill-differentiated labour.The models are represented by a set of complementarity problems. This facilitates a comparison of model properties and the choice of an appropriate solution algorithm.The study is mainly devoted to single period models. Such equilibrium models are interpreted as adiabatic approximations of processes in continuous time. A separation by the time scale of the processes and an application of the slaving principle should thus govern the choice of endogenous variables in the equilibrium formulation.digitalisering@umu
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King-Hele, Sarah. "The dynamics of religious change : a comparative study of five western countries." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/the-dynamics-of-religious-change-a-comparative-study-of-five-western-countries(5322cbc7-b74f-48af-bb12-1b367da23add).html.
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The two main theories of religious change are the secularization paradigm and the economic model of religion. The secularization paradigm’s main premise is that modernization weakens the power and authority of the church as an institution and reduces the importance of religion in the daily lives of the population. This paradigm applies well to Europe, but the United States acts as a powerful counter-example. Since the 1940s, religious attendance in the United States has remained generally stable, with approximately 40% of the population claiming to attend religious services, mostly in Christian churches, at least once a week. American sociologists explain this relative vitality with reference to an open and competitive religious marketplace, claiming that the innate desire for spirituality is met by the sheer diversity of religious groups in the United States. This economic model of religion applies poorly to the European situation. This thesis examines these apparent contradictions by considering the similarities and differences between the dynamics of religious change in five western countries since the 1970s or 1980s; the countries are Britain, Australia, New Zealand, Canada and the United States. The key question is which combination of dynamics is responsible for religious change in western countries. The effects of migration and fertility aside, all population change must be related to some combination of age, period or cohort effects; age effects are those that occur as people age, period effects are those that affect the whole population regardless of age, and cohort effects are often attributed to circumstances or events during youth. These different dynamics of religious change would each indicate different sources of religious change at the individual level, which may lend support to one theory of religious change over another. I show that there is overwhelming evidence that most religious change in Britain, Australia, New Zealand and Canada is due to differences between generations in the time periods observed with some slight downward period effects. The main drivers of change in the United States are either downward cohort with upward period effects, upward age effects, or a combination of these three effects. I conclude that the changing conditions of socialization in youth, both formal and informal, related to modernization and cultural shifts can explain the dynamics in Britain, Canada, Australia and New Zealand. Similar effects in the United States may be counteracted by the high social desirability of religion in that country by contrast with the other countries and the ability of particularly conservative Protestants in the United States to isolate themselves from views that conflict with their own; these groups are aided in this by numerical strength and by the ability to socialize, work and view media all of which enhance their religious worldview.
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Warren, Kimber Derek. "System dynamics modelling of strategic responses to exogenous change in the U.K. brewing industry." Thesis, London Business School (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244660.
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Ding, Zhengtao. "Dynamic model uncertainty and change detection with application to a diesel engine." Thesis, University of Manchester, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292779.
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Johnson, Jeffrey S. "A dynamic neural field model of visual working memory and change detection." Diss., University of Iowa, 2008. http://ir.uiowa.edu/etd/12.
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Kompil, Mert Çelik H. Murat. "Modeling retail structural change of İzmir using a dynamic spatial interaction model/." [s.l.]: [s.n.], 2004. http://library.iyte.edu.tr/tezler/master/sehirplanlama/T000469.rar.
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Milichovský, Miloš. "Dynamický model akumulátorů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220074.
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The thesis includes the basic principles of lead-acid, NiCd, NiMH and Li-Ion batteries. There is a description of their features and phenomena that processes in the batteries during charging and discharging. The most important part is devoted to dynamic models of these types of batteries, the parameters that are necessary for their modeling, and testing of absolute error models. Further, the model in Matlab was created which allows the simulation of the GRID-OFF photovoltaic system using the battery model.
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Franck, Travis Read. "Coastal communities and climate change : a dynamic model of risk perception, storms, and adaptation." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54846.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Engineering Systems Division, 2009.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student submitted PDF version of thesis.
Includes bibliographical references (p. 303-311).
Climate change impacts, including sea-level rise and changes in tropical storm frequency and intensity, will pose signicant challenges to city planners and coastal zone managers trying to make wise investment and protection decisions. Meanwhile, policymakers are working to mitigate impacts by regulating greenhouse gas emissions. To design effective policies, policymakers need more accurate information than is currently available to understand how coastal communities will be affected by climate change. My research aims to improve coastal impact and adaptation assessments, which inform climate and adaptation policies. I relax previous assumptions of probabilistic annual storm damage and rational economic expectations-variables in previous studies that are suspect, given the stochastic nature of storm events and the real-world behavior of people. I develop a dynamic stochastic adaptation model that includes explicit storm events and boundedly rational storm perception. I also include endogenous economic growth, population growth, public adaptation measures, and relative sea-level rise. The frequency and intensity of stochastic storm events can change a region's long- term economic growth pattern and introduce the possibility of community decline. Previous studies using likely annual storm damage are unable to show this result. Additionally, I consider three decision makers (coastal managers, infrastructure investors, and residents) who differ regarding their perception of storm risk. The decision makers' perception of risk varies depending on their rationality assumptions.
(cont.) Boundedly rational investors and residents perceive storm risk to be higher immediately after a storm event, which can drive down investment, decrease economic 3 growth, and increase economic recovery time, proving that previous studies provide overly optimistic economic predictions. Rationality assumptions are shown to change economic growth and recovery time estimates. Including stochastic storms and variable rationality assumptions will improve adaptation research and, therefore, coastal adaptation and climate change policies.
by Travis Read Franck.
Ph.D.
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Thonicke, Kirsten. "Fire disturbance and vegetation dynamics analysis and models /." Phd thesis, [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968686885.
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MacKay, Robert Malcolm. "The GCRC two-dimensional zonally averaged statistical dynamical climate model : development, model performance, and climate sensitivity /." Full text open access at:, 1994. http://content.ohsu.edu/u?/etd,199.
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Li, Yanmei. "The dynamic interaction between residential mortgage foreclosure, neighborhood characteristics, and neighborhood change." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1155522566.
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Leino, Martin. "Dynamical Systems Analysis of a Low-Dimensional Model of Paleoclimatic Change." Thesis, Uppsala universitet, Tillämpad matematik och statistik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-453024.
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Furtado, Jason C. "On the uncertainties and dynamics of Pacific interannual and decadal climate variability and climate change." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37302.
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Tropical and extratropical Pacific decadal climate variability substantially impact physical and biological systems in the Pacific Ocean and strongly influence global climate through teleconnection patterns. Current understanding of Pacific decadal climate variability centers around the El Niño-Southern Oscillation (ENSO), the Aleutian Low (AL), and the Pacific Decadal Oscillation (PDO). However, recent literature has highlighted the emerging roles of secondary modes of variability of the tropical and extratropical Pacific atmosphere and ocean in global climate change: the Central Pacific Warming (CPW) phenomenon, the North Pacific Oscillation (NPO), and the North Pacific Gyre Oscillation (NPGO). This work analyzes the statistics and uncertainties behind Pacific interannual and decadal-scale climate variability, and focuses on better understanding the roles of the CPW, NPO, and NPGO in the climate system.
The study begins by examining the dynamics of the NPO and its role in Pacific interannual and decadal climate variability. Results illustrate that the individual poles of the NPO have relations at high frequencies, but only the southern node contains a deterministic low-frequency component, which is forced by tropical Pacific sea surface temperature (SST) variability, as shown with a modeling experiment. The NPO-induced variability by the tropical Pacific SST is then integrated by the underlying ocean surface to form the decadal-scale NPGO signal. Thus, a new link between the CPW, the NPO, and the NPGO is formed, expanding the current framework of Pacific decadal variability and its implications for weather and climate.
The new framework of North Pacific decadal variability (NPDV) is then evaluated in 24 state-of-the-art coupled climate models. Results indicate that the models in general have difficulty reproducing the leading modes of NPDV in space and time, particularly the NPGO mode and its connection to the NPO. Furthermore, most models lack the proper connections between extratropical and tropical Pacific, for both the ENSO/AL/PDO and CPW/NPO/NPGO connections. Improvements in these teleconnections are thus needed to increase confidence in future climate projections.
The last part of the dissertation explores further the importance of the CPW mode by comparing and contrasting two popular paleoclimate SST anomaly reconstruction methods used for tropical Indo-Pacific SSTs. The first method exploits the high correlation between the canonical ENSO mode and tropical precipitation; the second method uses a multi-regression model that exploits the multiple modes of covariability between tropical precipitation and SSTs, including the CPW mode. The multi-regression approach demonstrates higher skill throughout the tropical Indo-Pacific than the first approach, illustrating the importance of including the CPW phenomenon in understanding past climates.
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Silva, Rui Pedro Guerreiro Duarte Rivaes. "Predicting the effects of climatic change on mediterranean riparian vegetation using a dynamic vegetation model." Master's thesis, ISA, 2010. http://hdl.handle.net/10400.5/2883.
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Mestrado em Gestão e Conservação de Recursos Naturais - Instituto Superior de AgronomiaThe present master's thesis, had as its main objective the application of a dynamic model of riparian habitats in a case study with pronounced mediterranean characteristics. he vegetation model used is based on the existence of water conditions (water height and distance to water) suitable for the development of each type of riparian vegetation in different stages of their development, modeling annually its space-time evolution. The rules underlying the model take into account the height of the flow, the shear stress and duration of flooding. The modeling of vegetation held in ArcGIS environment, bases on three general ohases: initial creation of landscape, simulation of temporal and spatial evolution of vegetation and the presentation of annual results.
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Chang, Biao. "Spatial analysis of sea level rise associated with climate change." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/49062.
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Sea level rise (SLR) is one of the most damaging impacts associated with climate change. The objective of this study is to develop a comprehensive framework to identify the spatial patterns of sea level in the historical records, project regional mean sea levels in the future, and assess the corresponding impacts on the coastal communities. The first part of the study suggests a spatial pattern recognition methodology to characterize the spatial variations of sea level and to investigate the sea level footprints of climatic signals. A technique based on artificial neural network is proposed to reconstruct average sea levels for the characteristic regions identified. In the second part of the study, a spatial dynamic system model (DSM) is developed to simulate and project the changes in regional sea levels and sea surface temperatures (SST) under different development scenarios of the world. The highest sea levels are predicted under the scenario A1FI, ranging from 71 cm to 86 cm (relative to 1990 global mean sea level); the lowest predicted sea levels are under the scenario B1, ranging from 51 cm to 64 cm (relative to 1990 global mean sea level). Predicted sea levels and SST's of the Indian Ocean are significantly lower than those of the Pacific and the Atlantic Ocean under all six scenarios. The last part of this dissertation assesses the inundation impacts of projected regional SLR on three representative coastal U.S. states through a geographic information system (GIS) analysis. Critical issues in the inundation impact assessment process are identified and discussed.
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Gowreesunker, Baboo Lesh Singh. "Phase change thermal enery storage for the thermal control of large thermally lightweight indoor spaces." Thesis, Brunel University, 2013. http://bura.brunel.ac.uk/handle/2438/7649.
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Energy storage using Phase Change Materials (PCMs) offers the advantage of higher heat capacity at specific temperature ranges, compared to single phase storage. Incorporating PCMs in lightweight buildings can therefore improve the thermal mass, and reduce indoor temperature fluctuations and energy demand. Large atrium buildings, such as Airport terminal spaces, are typically thermally lightweight structures, with large open indoor spaces, large glazed envelopes, high ceilings and non-uniform internal heat gains. The Heating, Ventilation and Air-Conditioning (HVAC) systems constitute a major portion of the overall energy demand of such buildings. This study presented a case study of the energy saving potential of three different PCM systems (PCM floor tiles, PCM glazed envelope and a retrofitted PCM-HX system) in an airport terminal space. A quasi-dynamic coupled TRNSYS®-FLUENT® simulation approach was used to evaluate the energy performance of each PCM system in the space. FLUENT® simulated the indoor air-flow and PCM, whilst TRNSYS® simulated the HVAC system. Two novel PCM models were developed in FLUENT® as part of this study. The first model improved the phase change conduction model by accounting for hysteresis and non-linear enthalpy-temperature relationships, and was developed using data from Differential Scanning Calorimetry tests. This model was validated with data obtained in a custom-built test cell with different ambient and internal conditions. The second model analysed the impact of radiation on the phase change behaviour. It was developed using data from spectrophotometry tests, and was validated with data from a custom-built PCM-glazed unit. These developed phase change models were found to improve the prediction errors with respect to conventional models, and together with the enthalpy-porosity model, they were used to simulate the performance of the PCM systems in the airport terminal for different operating conditions. This study generally portrayed the benefits and flexibility of using the coupled simulation approach in evaluating the building performance with PCMs, and showed that employing PCMs in large, open and thermally lightweight spaces can be beneficial, depending on the configuration and mode of operation of the PCM system. The simulation results showed that the relative energy performance of the PCM systems relies mainly on the type and control of the system, the night recharge strategy, the latent heat capacity of the system, and the internal heat gain schedules. Semi-active systems provide more control flexibility and better energy performance than passive systems, and for the case of the airport terminal, the annual energy demands can be reduced when night ventilation of the PCM systems is not employed. The semi-active PCM-HX-8mm configuration without night ventilation, produced the highest annual energy and CO2 emissions savings of 38% and 23%, respectively, relative to a displacement conditioning (DC) system without PCM systems.
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Zhu, En. "The role of US agricultural and forest activities in global climate change mitigation." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1406.
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Promchote, Parichart. "Linkage of Climate Diagnostics in Predictions for Crop Production: Cold Impacts in Taiwan and Thailand." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7512.
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This research presents three case studies of low temperature anomalies that occurred during the winter–spring seasons and their influence on extreme events and crop production. We investigate causes and effects of each climate event and developed prediction methods for crops based on the climate diagnostic information. The first study diagnosed the driven environmental-factors, including climate pattern, climate change, soils moisture, and sea level height, associated with the 2011 great flood in Thailand and resulting total crop loss. The second study investigated climate circulation and indices that contributed to wet-and-cold (WC) events leading to significant crop damage in Taiwan. We developed empirical–dynamical models based on prominent climate indices to confidently predict WC events as much as 6 months before they occur. The final study extends from the second study and predict chronic damage to rice crops from climate change by using a crop simulation model. The long-term prediction of rice growth and yield effectively illustrated both decreases and increases in yield depending on climate scenarios. The three studies are different in location and circumstances but the methodologies can be applied across Thailand, Taiwan, and other areas with similar agroclimatology.
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Rodríguez, Eraso Nelly. "Land-cover and land-use change and deforestation in Colombia: spatial dynamics, drivers and modelling." Doctoral thesis, Universitat Autònoma de Barcelona, 2011. http://hdl.handle.net/10803/84004.
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Este estudio analiza el cambio en la cobertura y uso del suelo con énfasis en los procesos de deforestación en dos regiones contrastantes de Colombia: Andes y Guyana, entre 1985 y 2005. Se aplicó un enfoque espacial y temporal a partir del análisis del cambio de uso y cobertura del suelo (LULCC) para evaluar y predecir los procesos de cambios asociándolos a variables explicativas y junto con métricas del paisaje y sistemas de información geográfica se analizaron patrones y tendencias de deforestación.
La utilización del suelo es el resultado de la interacción de una serie de factores biofísicos, económicos, tecnológicos, institucionales, culturales, etc, que operan en un rango de escalas espaciales y temporales y se correlacionan con los procesos y patrones del paisaje. Dado que los cambios en el uso de la tierra son cada vez más rápidos, es necesario comprender las fuerzas que impulsan esos cambios y predecir sus efectos sobre los procesos del ecosistema o del ambiente global
La información de cobertura del suelo para el presente estudio se basó en la interpretación de imágenes satelitales y las variables explicativas incluyeron datos biofísicos y socioeconómicos provenientes de una amplia gama de fuentes de información. Para la región de los Andes, el enfoque se dirigió a la aplicación de modelos de cambio de la tierra y de deforestación entre bosques montanos (montane forest) y bosques de piedemonte (lowland forest), usando enfoques espacialmente explícitos (Land Change Modeler-LCM) y modelos lineales generalizados (GLM). A nivel de la región de la Guayana, se estudiaron los patrones de deforestación en los modelos de ocupación típicos de la región, comparando tasas de cambio, patrones del paisaje y efectividad de figuras de conservación. Finalmente se modelizo el potencial de cambio futuro en ambas regiones prediciendo su evolución e identificando zonas de alto riesgo de deforestación y sus implicaciones frente a la conservación de la biodiversidad.
Las tasas de deforestación varían entre las regiones y al interior de ellas. Para los Andes la tasa anual de deforestación fue de 1.41%, mientras que para Guayana de 0.25%; sin embargo en Guyana se evidenciaron las mayores tasas asociadas con una fase rápida e intermedia de pérdida de bosque en un modelo de transición de colono a establecimientos permanentes. Los modelos utilizados en esta tesis, sugiere que el modelo espacial de LCM basado en probabilidades de Markov tiene un mejor respuesta para explicar los cambios en el uso del suelo que los modelos lineales generalizados. La variable explicativa que mayor incide en los procesos de cambio de uso del suelo y deforestación es la distancia de las carreteras, pero existen variables como la actividad económica, pendiente, distancia a pastos y precipitación que impulsan procesos de cambio y el peso de estas variables depende del tipo de bosques y la región.
Los resultados de esta tesis mostraron que algunas figuras de protección como el sistema de parques naturales nacionales y los resguardos indígenas pueden ser efectivas para frenar procesos de deforestación y que las zonas de transición entre Andes y Amazonia, Orinoquia y Magdalena Medio se encuentran bajo una mayor amenaza de conversión probable debido a su accesibilidad y migración de la población. Finalmente, una mejor comprensión de la dinámica de LULCC en Colombia, es un paso importante en el desarrollo de estrategias de planificación del territorio y conservación de la región y las investigaciones futuras deberán evaluar la incidencia de las políticas nacionales tales como tenencia de la tierra, REDD, políticas sectoriales, económicas y energéticas ante cambios en el uso del suelo y la deforestación.This study analyzes the land cover change with emphasis on the deforestation processes in two contrasting regions of Colombia: Andes and Guyana between 1985 and 2005. A spatial and temporal statistical approach was applied from the analysis of land cover change to evaluate and predict the processes of change associated with explanatory variables and together with metrics of landscape and systems of information patterns and tendencies of deforestation were analyzed. Land use is the result of the interaction of a series of biophysical, economic, technologic, institutional and cultural factors, among others, that operate in a level of spatial and temporal scales and correlate with landscape processes and partners. Given land change are faster and faster, it is necessary to understand the strengths that drive those changes and predict their effects on the processes of the ecosystem or the global environment. Land use information for this study was based on the interpretation of satellite images and the explanatory variables including biophysical and socioeconomic data from a wide range of source of information. For the Andean region, the approach was directed towards the application of land change and deforestation models in montane and lowland forests, using Land Change Modeler – LCM and Generalized Lineal Models (GLM). At the level of La Guyana region, the patterns of deforestation were studied in the models of typical occupation of the region, comparing change rates, landscape patterns and effectiveness of figures of conservation. Finally the potential of change was modeled in both regions predicting its evolution and identifying zones of high risk of deforestation and their implications in the conservation of the biodiversity. The rates of deforestation vary in the regions and in the inside of them. For the Andean region the annual rate of deforestation was 1.41%, whereas for Guyana was 0.25%; however in Guyana the highest rates were showed associated with a fast and intermediate stage of loss of forest in a transition model from settler to permanent establishment. The models used in this thesis, suggest that the spatial model of LCM based on probabilities of Markov has a better response to explain land use changes than the generalized lineal models. The explanatory variable that greatly affect in land use change processes is the distance of roads, but variables like the economic activity, slope, distance to pasture and precipitation exist and drive processes of change and the burden of these variables depend on the type of forests and the region. The results of this thesis showed that some figures of protection like the system of National Natural Parks and the indigenous reserves can be effective to hold deforestation processes back and that the transition zones between Andes and Amazonia, Orinoquia and Magdalena Medio are under a greater threat of conversion probably because of their accessibility and migration of the population. Finally, a better understanding of the dynamic of LULCC in Colombia, is an important step in the development of strategies of planning of the territory and conservation of the region and the future investigations must evaluate the incident of the national policies, like land ownership, REDD, sectorial, economic and energetic policies in the view of land use change and the deforestation.
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Berndt, Christian. "Ruhr companies between dynamic change and institutional persistence : globalisation, the 'German Model' and regional place dependence." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624983.
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Anputhas, Markandu. "Simulating land use change for assessing future dynamics of land and water resources." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/56181.
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Models of land use change fall into two broad categories: pattern based and process based. This thesis focuses on pattern based land use change models, expanding our understanding of these models in three important ways.
First, it is demonstrated that some driving variables do not have a smooth impact on the land use transition process. Our example variable is access to water. Land managers with access to piped water do not have any need for surface or groundwater. For variables like this, a model needs to change the way that driving variables are represented. The second important result is that including a variable which captures spatial correlation between land use types significantly increases the explanatory power of the prediction model. A major weakness of pattern based land use models is their inability to model interactions between neighbouring land parcels; the method proposed in this study can be an alternative to account for spatial neighbourhood association.
These innovations are applied using the CLUE-S (Conversion of Land Use and its Effects at Small regional extent) system to the Deep Creek watershed in the Southern Interior of British Columbia. The results highlight the challenge of balancing the protection of agricultural land and conserving forest and natural areas when population and economic growth are inevitable. The results also demonstrate the implications of land use change on existing land use policies.
The calibrated model was validated using remote sensing data. A series of discriminant functions were estimated for each land use type in the recent period and these functions were then used to classify. The calibrated model was run in reverse, back to the generated land use classification, and results compared. Fit was reasonable with error rates falling below ten percent when radii beyond 2.5 km were considered.
Another important contribution is demonstrating the importance of modelling dynamic variables. Some important drivers are changing continuously and others depend on land use change itself. Failure to update these variables will bias model forecasts. Spatial neighbourhood association, an endogenous variable governed by land use change itself, is again used as the example dynamic variable. The study demonstrates the importance of updating all associated information.Graduate Studies, College of (Okanagan)
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Zhang, Bai. "Modeling and Characterization of Dynamic Changes in Biological Systems from Multi-platform Genomic Data." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/29111.
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Biological systems constantly evolve and adapt in response to changed environment and external stimuli at the molecular and genomic levels. Building statistical models that characterize such dynamic changes in biological systems is one of the key objectives in bioinformatics and computational biology. Recent advances in high-throughput genomic and molecular profiling technologies such as gene expression and and copy number microarrays provide ample opportunities to study cellular activities at the individual gene and network levels. The aim of this dissertation is to formulate mathematically dynamic changes in biological networks and DNA copy numbers, to develop machine learning algorithms to learn these statistical models from high-throughput biological data, and to demonstrate their applications in systems biological studies.
The first part (Chapters 2-4) of the dissertation focuses on the dynamic changes taking placing at the biological network level. Biological networks are context-specific and dynamic in nature. Under different conditions, different regulatory components and mechanisms are activated and the topology of the underlying gene regulatory network changes. We report a differential dependency network (DDN) analysis to detect statistically significant topological changes in the transcriptional networks between two biological conditions. Further, we formalize and extend the DDN approach to an effective learning strategy to extract structural changes in graphical models using l1-regularization based convex optimization. We discuss the key properties of this formulation and introduce an efficient implementation by the block coordinate descent algorithm. Another type of dynamic changes in biological networks is the observation that a group of genes involved in certain biological functions or processes coordinate to response to outside stimuli, producing distinct time course patterns. We apply the echo stat network, a new architecture of recurrent neural networks, to model temporal gene expression patterns and analyze the theoretical properties of echo state networks with random matrix theory.
The second part (Chapter 5) of the dissertation focuses on the changes at the DNA copy number level, especially in cancer cells. Somatic DNA copy number alterations (CNAs) are key genetic events in the development and progression of human cancers, and frequently contribute to tumorigenesis. We propose a statistically-principled in silico approach, Bayesian Analysis of COpy number Mixtures (BACOM), to accurately detect genomic deletion type, estimate normal tissue contamination, and accordingly recover the true copy number profile in cancer cells.Ph. D.
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Aho, P. (Pekka). "Automated state model extraction, testing and change detection through graphical user interface." Doctoral thesis, Oulun yliopisto, 2019. http://urn.fi/urn:isbn:9789526224060.
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Abstract Testing is an important part of quality assurance, and the use of agile processes, continuous integration and DevOps is increasing the pressure for automating all aspects of testing. Testing through graphical user interfaces (GUIs) is commonly automated by scripts that are captured or manually created with a script editor, automating the execution of test cases. A major challenge with script-based GUI test automation is the manual effort required for maintaining the scripts when the GUI changes. Model-based testing (MBT) is an approach for automating also the design of test cases. Traditionally, models for MBT are designed manually with a modelling tool, and an MBT tool is used for generating abstract test cases from the model. Then, an adapter is implemented to translate the abstract test cases into concrete test cases that can be executed on system under test (SUT). When the GUI changes, the model has to be updated and the test cases can be generated from the updated model, reducing the maintenance effort. However, designing models and implementing adapters requires effort and specialized expertise. The main research questions of this thesis are 1) how to automatically extract state-based models of software systems with GUI, and 2) how to use the extracted models to automate testing. Our focus is on using dynamic analysis through the GUI during automated exploration of the system, and we concentrate on desktop applications. Our results show that extracting state models through GUI is possible and the models can be used to generate regression test cases, but a more promising approach is to use model comparison on extracted models of consequent system versions to automatically detect changes between the versionsTiivistelmä Testaaminen on tärkeä osa laadun varmistusta. Ketterät kehitysprosessit ja jatkuva integrointi lisäävät tarvetta automatisoida kaikki testauksen osa-alueet. Testaus graafisten käyttöliittymien kautta automatisoidaan yleensä skripteinä, jotka luodaan joko tallentamalla manuaalista testausta tai kirjoittamalla käyttäen skriptieditoria. Tällöin scriptit automatisoivat testitapausten suorittamista. Muutokset graafisessa käyttöliittymässä vaativat scriptien päivittämistä ja scriptien ylläpitoon kuluva työmäärä on iso ongelma. Mallipohjaisessa testauksessa automatisoidaan testien suorittamisen lisäksi myös testitapausten suunnittelu. Perinteisesti mallipohjaisessa testauksessa mallit suunnitellaan manuaalisesti käyttämällä mallinnustyökalua, ja mallista luodaan abstrakteja testitapauksia automaattisesti mallipohjaisen testauksen työkalun avulla. Sen jälkeen implementoidaan adapteri, joka muuttaa abstraktit testitapaukset konkreettisiksi, jotta ne voidaan suorittaa testattavassa järjestelmässä. Kun testattava graafinen käyttöliittymä muuttuu, vain mallia täytyy päivittää ja testitapaukset voidaan luoda automaattisesti uudelleen, vähentäen ylläpitoon käytettävää työmäärää. Mallien suunnittelu ja adapterien implementointi vaatii kuitenkin huomattavan työmäärän ja erikoisosaamista. Tämä väitöskirja tutkii 1) voidaanko tilamalleja luoda automaattisesti järjestelmistä, joissa on graafinen käyttöliittymä, ja 2) voidaanko automaattisesti luotuja tilamalleja käyttää testauksen automatisointiin. Tutkimus keskittyy työpöytäsovelluksiin ja dynaamisen analyysin käyttämiseen graafisen käyttöliittymän kautta järjestelmän automatisoidun läpikäynnin aikana. Tutkimustulokset osoittavat, että tilamallien automaattinen luominen graafisen käyttöliittymän kautta on mahdollista, ja malleja voidaan käyttää testitapausten generointiin regressiotestauksessa. Lupaavampi lähestymistapa on kuitenkin vertailla malleja, jotka on luotu järjestelmän peräkkäisistä versioista, ja havaita versioiden väliset muutokset automaattisesti
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Salge, Markus. "Struktur und Dynamik ganzheitlicher Verbesserungsprogramme in der industriellen Fertigung ein systemdynamisches Modell zur nachhaltigen Gestaltung des Wandels in Industrieunternehmen." Hamburg Kovač, 2008. http://d-nb.info/994678339/04.
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Nhemachena, Charles. "Agriculture and future climate dynamics in Africa impacts and adaptation options /." Thesis, Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-05302009-122839/.
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Vaswani, Namrata. "Change detection in stochastic shape dynamical models with applications in activity modeling and abnormality detection." College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/1787.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2004.Thesis research directed by: Electrical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Beckmann, Joshua S. "The effects of stimulus dynamics on temporal discrimination : implications for change and internal clock models of timing /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1464112891&sid=9&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Thesis (Ph. D.)--Southern Illinois University Carbondale, 2007."Department of Psychology." Keywords: Pacemaker, Stimulus, Temporal discrimination, Internal clock, Timing Includes bibliographical references (p.87-90 ). Also available online.
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Singh, Karandeep. "Statistical modelling and analysis of traffic : a dynamic approach." Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/9421.
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In both developed and emerging-economies, major cities continue to experience increasing traffic congestion. To address this issue, complex Traffic Management Systems (TMS) are employed in recent years to help manage traffic. These systems fuse traffic-surveillance-related information from a variety of sensors deployed across traffic networks. A TMS requires real-time information to make effective control decisions and to deliver trustworthy information to users, such as travel time, congestion level, etc. There are three fundamental inputs required by TMS, namely, traffic volume, vehicular speed, and traffic density. Using conventional traffic loop detectors one can directly measure flow and velocity. However, traffic density is more difficult to measure. The situation becomes more difficult for multi-lane motorways due to drivers lane-change behaviour. This research investigates statistical modelling and analysis of traffic flow. It contributes to the literature of transportation and traffic management and research in several aspects. First, it takes into account lane-changes in traffic modelling through incorporating a Markov chain model to describe the drivers lane-change behaviour. Secondly, the lane change probabilities between two adjacent lanes are not assumed to be fixed but rather they depend on the current traffic condition. A discrete choice model is used to capture drivers lane choice behaviour. The drivers choice probabilities are modelled by several traffic-condition related attributes such as vehicle time headway, traffic density and speed. This results in a highly nonlinear state equation for traffic density. To address the issue of high nonlinearity of the state space model, the EKF and UKF is used to estimate the traffic density recursively. In addition, a new transformation approach has been proposed to transform the observation equation from a nonlinear form to a linear one so that the potential approximation in the EKF & UKF can be avoided. Numerical studies have been conducted to investigate the performance of the developed method. The proposed method outperformed the existing methods for traffic density estimation in simulation studies. Furthermore, it is shown that the computational cost for updating the estimate of traffic densities for a multi-lane motorway is kept at a minimum so that online applications are feasible in practice. Consequently the traffic densities can be monitored and the relevant information can be fed into the traffic management system of interest.
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MAGEE, KEVIN S. "TESTING THE REGIONAL RELIABILITY OF SATELLITE-BASED CHANGE DETECTION METHODOLOGY OF ARCHAEOLOGICAL PHENOMENA: A MODEL OF DYNAMIC MONITORING." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1189535419.
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Thellman, Jonas. "Vehicle Dynamics Testing in Advanced DrivingSimulators Using a Single Track Model." Thesis, Linköpings universitet, Fordonssystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-79397.
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The purpose of this work is to investigate if simple vehicle models are realisticand useful in simulator environment. These simple models have been parametrisedby the Department of Electrical Engineering at Linköping University and havebeen validated with good results. The models have been implemented in a simulatorenvironment and a simulator study was made with 24 participants. Eachtest person drove both slalom and double lane change manoeuvres with the simplemodels and with VTI’s advanced model. The test persons were able to successfullycomplete double lane changes for higher velocities with the linear tyre modelcompared to both the non-linear tyre model and the advanced model. The wholestudy shows that aggressive driving of a simple vehicle model with non-linear tyredynamics is perceived to be quite similar to an advanced model. It is noted significantdifferences between the simple models and the advanced model when drivingunder normal circumstances, e.g. lack of motion cueing in the simple model suchas pitch and roll.
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Schaal, Peter. "Observer-based engine air charge characterisation : rapid, observer-assisted engine air charge characterisation using a dynamic dual-ramp testing method." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/33247.
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Characterisation of modern complex powertrains is a time consuming and expensive process. Little effort has been made to improve the efficiency of testing methodologies used to obtain data for this purpose. Steady-state engine testing is still regarded as the golden standard, where approximately 90% of testing time is wasted waiting for the engine to stabilize. Rapid dynamic engine testing, as a replacement for the conventional steady-state method, has the potential to significantly reduce the time required for characterisation. However, even by using state of the art measurement equipment, dynamic engine testing introduces the problem that certain variables are not directly measurable due to the excitation of the system dynamics. Consequently, it is necessary to develop methods that allow the observation of not directly measurable quantities during transient engine testing. Engine testing for the characterisation of the engine air-path is specifically affected by this problem since the air mass flow entering the cylinder is not directly measurable by any sensor during transient operation. This dissertation presents a comprehensive methodology for engine air charge characterisation using dynamic test data. An observer is developed, which allows observation of the actual air mass flow into the engine during transient operation. The observer is integrated into a dual-ramp testing procedure, which allows the elimination of unaccounted dynamic effects by averaging over the resulting hysteresis. A simulation study on a 1-D gas dynamic engine model investigates the accuracy of the developed methodology. The simulation results show a trade-off between time saving and accuracy. Experimental test result confirm a time saving of 95% compared to conventional steady-state testing and at least 65% compared to quasi steady-state testing while maintaining the accuracy and repeatability of conventional steady-state testing.
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Edirisinghe, Pathirannehelage Neranjan S. "Charge Transfer in Deoxyribonucleic Acid (DNA): Static Disorder, Dynamic Fluctuations and Complex Kinetic." Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/phy_astr_diss/45.
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The fact that loosely bonded DNA bases could tolerate large structural fluctuations, form a dissipative environment for a charge traveling through the DNA. Nonlinear stochastic nature of structural fluctuations facilitates rich charge dynamics in DNA. We study the complex charge dynamics by solving a nonlinear, stochastic, coupled system of differential equations. Charge transfer between donor and acceptor in DNA occurs via different mechanisms depending on the distance between donor and acceptor. It changes from tunneling regime to a polaron assisted hopping regime depending on the donor-acceptor separation. Also we found that charge transport strongly depends on the feasibility of polaron formation. Hence it has complex dependence on temperature and charge-vibrations coupling strength. Mismatched base pairs, such as different conformations of the G・A mispair, cause only minor structural changes in the host DNA molecule, thereby making mispair recognition an arduous task. Electron transport in DNA that depends strongly on the hopping transfer integrals between the nearest base pairs, which in turn are affected by the presence of a mispair, might be an attractive approach in this regard. I report here on our investigations, via the I –V characteristics, of the effect of a mispair on the electrical properties of homogeneous and generic DNA molecules. The I –V characteristics of DNA were studied numerically within the double-stranded tight-binding model. The parameters of the tight-binding model, such as the transfer integrals and on-site energies, are determined from first-principles calculations. The changes in electrical current through the DNA chain due to the presence of a mispair depend on the conformation of the G・A mispair and are appreciable for DNA consisting of up to 90 base pairs. For homogeneous DNA sequences the current through DNA is suppressed and the strongest suppression is realized for the G(anti)・A(syn) conformation of the G・A mispair. For inhomogeneous (generic) DNA molecules, the mispair result can be either suppression or an enhancement of the current, depending on the type of mispairs and actual DNA sequence.
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Breininger, David. "Landcover Change and Population Dynamics of Florida Scrub-Jays and Florida Grasshopper Sparrows." Doctoral diss., University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3355.
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I confronted empirical habitat data (1994-2004) and population data (1988-2005) with ecological theory on habitat dynamics, recruitment, survival, and dispersal to develop predictive relationships between landcover variation and population dynamics. I focus on Florida Scrub-Jays, although one chapter presents a model for the potential influence of habitat restoration on viability of the Florida Grasshopper Sparrow. Both species are unique to Florida landscapes that are dominated by shrubs and grasses and maintained by frequent fires. Both species are declining, even in protected areas, despite their protected status. I mapped habitat for both species using grid polygon cells to quantify population potential and habitat quality. A grid cell was the average territory size and the landcover unit in which habitat-specific recruitment and survival occurred. I measured habitat-specific recruitment and survival of Florida Scrub-Jays from 1988-2008. Data analyses included multistate analysis, which was developed for capture-recapture data but is useful for analyzing many ecological processes, such as habitat change. I relied on publications by other investigators for empirical Florida Grasshopper Sparrow data. The amount of potential habitat was greatly underestimated by landcover mapping not specific to Florida Scrub-Jays. Overlaying east central Florida with grid polygons was an efficient method to map potential habitat and monitor habitat quality directly related to recruitment, survival, and management needs. Most habitats for both species were degraded by anthropogenic reductions in fire frequency. Degradation occurred across large areas. Florida Scrub-Jay recruitment and survival were most influenced by shrub height states. Multistate modeling of shrub heights showed that state transitions were influenced by vegetation composition, edges, and habitat management. Measured population declines of 4% per year corroborated habitat-specific modeling predictions. Habitat quality improved over the study period but not enough to recover precariously small populations. The degree of landcover fragmentation influenced mean Florida Scrub-Jay dispersal distances but not the number of occupied territories between natal and breeding territories. There was little exchange between populations, which were usually further apart than mean dispersal distances. Florida Scrub-Jays bred or delayed breeding depending on age, sex, and breeding opportunities. I show an urgent need also for Florida Grasshopper Sparrow habitat restoration given that the endangered bird has declined to only two sizeable populations and there is a high likelihood for continued large decline. A major effect of habitat fragmentation identified in this dissertation that should apply to many organisms in disturbance prone systems is that fragmentation disrupts natural processes, reducing habitat quality across large areas. Humans have managed wildland fire for > 40,000 years, so it should be possible to manage habitat for many endangered species that make Florida's biodiversity unique. This dissertation provides methods to quantify landscape units into potential source and sink territories and provides a basis for applying adaptive management to reach population and conservation goals.Ph.D.
Department of Biology
Sciences
Conservation Biology PhD
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Mayor, Louise Charlotte. "The adsorption and charge-transfer dynamics of model dye-sensitised solar cell surfaces." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/13521/.
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In this thesis, the dye molecule cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium(II) (N3) is studied on the rutile TiO2(110) and Au(111) surfaces. The molecules were deposited onto the surfaces using an ultra-high vacuum (UHV) electrospray deposition system. Thermally labile molecules such as N3 cannot be deposited using the typical method of thermal sublimation, so development of this deposition technique was a necessary step for entirely in situ experiments. The geometric and electronic structure of the samples are characterised using core-level and valence band photoemission spectroscopy, x-ray absorption fine structure spectroscopy, density functional theory, resonant x-ray emission spectroscopy and scanning tunnelling microscopy. These reveal that N3 bonds to TiO2(110) by deprotonation of the carboxyl groups of one bi-isonicotinic acid ligand so that its oxygen atoms bond to titanium atoms of the substrate, and one of the thiocyanate groups bonds via a sulphur atom to an oxygen atom of the substrate. N3 bonds to Au(111) via sulphur atoms with no deprotonation of the carboxylic groups, and at low coverages decorates the Au(111) herringbone reconstruction. For N3 on TiO2, a consideration of the energetics in relation to optical absorption is used to identify the main photoexcitation channel between occupied and unoccupied molecular orbitals in this system, and also to quantify the relative binding energies of core and valence excitons. For N3 on Au(111), the energetics show that the highest occupied molecular orbital overlaps with the Au conduction band. The transfer of charge between the N3 molecule and the TiO2(110) and Au(111) surfaces was studied using resonant photoemission spectroscopy and resonant x-ray emission spectroscopy. These techniques, combined with knowledge gained about the geometric and electronic structure, are used to determine the locations and electronic levels of N3 from which charge is readily transferred to the substrate. The core-hole clock implementation of resonant photoemission spectroscopy is used to reveal that electron delocalisation from N3 to TiO2(110) occurs within 16 femtoseconds.
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Veprauskas, Amy, and J. M. Cushing. "A juvenile–adult population model: climate change, cannibalism, reproductive synchrony, and strong Allee effects." TAYLOR & FRANCIS LTD, 2016. http://hdl.handle.net/10150/623279.
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We study a discrete time, structured population dynamic model that is motivated by recent field observations concerning certain life history strategies of colonial- nesting gulls, specifically the glaucouswinged gull ( Larus glaucescens). The model focuses on mechanisms hypothesized to play key roles in a population's response to degraded environment resources, namely, increased cannibalism and adjustments in reproductive timing. We explore the dynamic consequences of these mechanics using a juvenile- adult structure model. Mathematically, the model is unusual in that it involves a high co- dimension bifurcation at R0 = 1 which, in turn, leads to a dynamic dichotomy between equilibrium states and synchronized oscillatory states. We give diagnostic criteria that determine which dynamic is stable. We also explore strong Allee effects caused by positive feedback mechanisms in the model and the possible consequence that a cannibalistic population can survive when a non- cannibalistic population cannot.
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Sarmento, Cabral Juliano. "Demographic processes determining the range dynamics of plant species, and their consequences for biodiversity maintenance in the face of environmental change." Phd thesis, Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2010/4118/.
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The present thesis aims to introduce process-based model for species range dynamics that can be fitted to abundance data. For this purpose, the well-studied Proteaceae species of the South African Cape Floristic Region (CFR) offer a great data set to fit process-based models. These species are subject to wildflower harvesting and environmental threats like habitat loss and climate change. The general introduction of this thesis presents shortly the available models for species distribution modelling. Subsequently, it presents the feasibility of process-based modelling. Finally, it introduces the study system as well as the objectives and layout.
In Chapter 1, I present the process-based model for range dynamics and a statistical framework to fit it to abundance distribution data. The model has a spatially-explicit demographic submodel (describing dispersal, reproduction, mortality and local extinction) and an observation submodel (describing imperfect detection of individuals). The demographic submodel links species-specific habitat models describing the suitable habitat and process-based demographic models that consider local dynamics and anemochoric seed dispersal between populations. After testing the fitting framework with simulated data, I applied it to eight Proteaceae species with different demographic properties. Moreover, I assess the role of two other demographic mechanisms: positive (Allee effects) and negative density-dependence. Results indicate that Allee effects and overcompensatory local dynamics (including chaotic behaviour) seem to be important for several species. Most parameter estimates quantitatively agreed with independent data. Hence, the presented approach seemed to suit the demand of investigating non-equilibrium scenarios involving wildflower harvesting (Chapter 2) and environmental change (Chapter 3).
The Chapter 2 addresses the impacts of wildflower harvesting. The chapter includes a sensitivity analysis over multiple spatial scales and demographic properties (dispersal ability, strength of Allee effects, maximum reproductive rate, adult mortality, local extinction probability and carrying capacity). Subsequently, harvesting effects are investigated on real case study species. Plant response to harvesting showed abrupt threshold behavior. Species with short-distance seed dispersal, strong Allee effects, low maximum reproductive rate, high mortality and high local extinction are most affected by harvesting. Larger spatial scales benefit species response, but the thresholds become sharper. The three case study species supported very low to moderate harvesting rates. Summarizing, demographic knowledge about the study system and careful identification of the spatial scale of interest should guide harvesting assessments and conservation of exploited species. The sensitivity analysis’ results can be used to qualitatively assess harvesting impacts for poorly studied species.
I investigated in Chapter 3 the consequences of past habitat loss, future climate change and their interaction on plant response. I use the species-specific estimates of the best model describing local dynamics obtained in Chapter 1. Both habitat loss and climate change had strong negative impacts on species dynamics. Climate change affected mainly range size and range filling due to habitat reductions and shifts combined with low colonization. Habitat loss affected mostly local abundances. The scenario with both habitat loss and climate change was the worst for most species. However, this impact was better than expected by simple summing of separate effects of habitat loss and climate change. This is explained by shifting ranges to areas less affected by humans. Range size response was well predicted by the strength of environmental change, whereas range filling and local abundance responses were better explained by demographic properties. Hence, risk assessments under global change should consider demographic properties. Most surviving populations were restricted to refugia, serving as key conservation focus.The findings obtained for the study system as well as the advantages, limitations and potentials of the model presented here are further discussed in the General Discussion. In summary, the results indicate that 1) process-based demographic models for range dynamics can be fitted to data; 2) demographic processes improve species distribution models; 3) different species are subject to different processes and respond differently to environmental change and exploitation; 4) density regulation type and Allee effects should be considered when investigating range dynamics of species; 5) the consequences of wildflower harvesting, habitat loss and climate change could be disastrous for some species, but impacts vary depending on demographic properties; 6) wildflower harvesting impacts varies over spatial scale; 7) The effects of habitat loss and climate change are not always additive.Das Ziel dieser Studie bestand daher darin, prozess-basierte Modelle zu entwickeln, die mit Daten zur Abundanz von Arten parametrisiert werden können. Die außergewöhnlich gut erforschten Proteaceen der südafrikanischen Kapregion (CFR), für die ein umfangreicher Datensatz zur Verfügung steht, stellen ein sehr geeignetes Untersuchungssystem zur Erstellung derartiger prozess-basierter Modelle dar. In Kapitel 1 beschreibe ich ein prozess-basiertes Modell für die Verbreitungsdynamik sowie die Methoden zur Parametrisierung des Modells mit Daten zu Abundanzverteilungen. Das Modell umfasst ein räumlich-explizites demographisches Modul und ein Beobachtungsmodul. Das demographische Modul verbindet artspezifische Habitatmodelle, die das geeignete Habitat beschreiben, und prozess-basierte demographische Modelle, die die lokale Dynamik und die Windausbreitung von Samen umfassen. Nach der Überprüfung der Parametrisierungs¬methoden mit simulierten Daten, wende ich die Modelle auf acht Proteaceenarten mit unterschiedlichen demographischen Eigenschaften an. Außerdem untersuche ich die Rolle von positiver (Allee-Effekte) und negativer Dichte-Abhängigkeit. Die Ergebnisse zeigen, dass Allee-Effekte und überkompensatorische Dynamik für viele Arten tatsächlich eine Rolle spielen. Der Großteil der geschätzten Parameter stimmt quantitativ mit unabhängigen Daten und beschreibt erfolgreich, wie die Abundanzverteilung aus der Bewegung und Interaktion der Individuen entsteht. Die vorgestellten Methoden scheinen daher zur Untersuchung von Ungleichgewichtsszenarien geeignet, die die Ernte von Infloreszenzen in Wildbeständen (Kapitel 2) und Umweltwandel (Kapitel 3) einschließen. In Kapitel 2 untersuche ich die Effekte der Ernte von Infloreszenzen in Wildbeständen. Das Kapitel beinhaltet eine Sensitivitätsanalyse über mehrere räumliche Skalen sowie demographische Eigenschaften. Darauf folgend wurden die Effekte der Ernte anhand von drei realen Arten untersucht. Die Reaktion der Pflanzen auf die Ernte zeigte ein Verhalten mit abrupten Schwellenwerten. Die durch die Ernte am stärksten gefährdeten Arten zeichneten sich durch kurze Samenausbreitungsdistanzen, starke Allee Effekte, geringe maximale Reproduktionsrate, hohe Mortalität und hohe lokale Aussterbewahrscheinlichkeit aus. Die Betrachtung größerer räumlicher Skalen wirkte sich trotz schärferer Grenzwerte positiv auf die Reaktion der Arten aus. Die drei untersuchten realen Arten konnten sehr geringe bis mittlere nachhaltige Ernteraten ertragen. Zusammenfassend lässt sich sagen, dass Kenntnisse über die Demographie des Untersuchungssystems und die umsichtige Identifizierung der zu betrachtenden räumlichen Skala zu einer besseren Einschätzung der Ernteintensität und der Naturschutzziele führen sollten. In Kapitel 3 wird die Reaktion der Arten auf vergangene Habitatverluste und zukünftigen Klimawandel sowie die Interaktion der beiden untersucht. Der Klimawandel wirkte sich dabei vornehmlich negativ auf die Größe des Verbreitungsgebiets und die Ausnutzung des potentiellen Habitats (‚Range Filling’) aus, wobei es zu einer Verschiebung des Habitats ohne erfolgreiche Kolonisierung kam. Der Habitatverlust reduzierte vor allem die lokalen Abundanzen. Die meisten Arten wurden vor allem durch das Szenario mit beiden Klimawandel und Habitatsverlust stark beeinträchtigt. Der negative Effekt war allerdings geringer als nach einer einfachen Aufsummierung der Einzeleffekte zu erwarten wäre. Dies erklärt sich aus einer Verschiebung des Verbreitungsgebiets der Arten in Regionen, in denen es in der Vergangenheit zu geringeren Habitatverlusten kam. Die Größe des Verbreitungsgebiets wurde am besten durch die Stärke des Umweltwandels vorhergesagt, wogegen das Range Filling und die lokalen Abundanzen hauptsächlich von den demographischen Eigenschaften abhingen. Aus diesen Ergebnissen lässt sich schließen, dass Abschätzungen des Aussterbensrisikos unter Umweltwandel demographische Eigenschaften einbeziehen sollten. Die meisten überlebenden Populationen waren auf Refugien reduziert, die im Fokus der Naturschutzmaßnahmen stehen sollten. Zusammenfassend zeigen die Ergebnisse, dass 1) prozess-basierte demographische Modelle für die Verbreitungsdynamik von Arten mit Daten parametrisierbar sind; 2) die Einbeziehung demographischer Prozesse die Modelle für die Verbreitung von Arten verbessert; 3) verschiedene Arten von unterschiedlichen Prozessen beeinflusst werden und unterschiedlich auf Umweltwandel und Beerntung reagieren; 4) Dichteregulierung und Allee-Effekte bei der Untersuchung der Verbreitungsdynamik von Arten berücksichtigt werden sollten; 5) die Ernte von Infloreszenzen in Wildbeständen, sowie Habitatverlust und Klimawandel für manche Arten katastrophale Folgen haben können, deren Effekte aber von den demographischen Eigenschaften abhängen; 6) der Einfluss der Beerntung in Abhängigkeit von der betrachteten räumlichen Skala variiert; 7) die Effekte von Habitatverlust und Klimawandel nicht additiv sind.
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Magee, Kevin S. "Testing the regional reliability of satellite-based change detection methodology of archaeological phenomena a model of dynamic monitoring /." Cincinnati, Ohio : University of Cincinnati, 2007. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1189535419.
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Thesis (M.A.)--University of Cincinnati, 2007.Advisor: Alan P. Sullivan, III. Title from electronic thesis title page (viewed Feb 5, 2008). Includes abstract. Keywords: change detection; archaeology; Upper Basin; UBARP. Includes bibliographical references.
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Valayamkunnath, Prasanth. "Understanding the Role of Vegetation Dynamics and Anthropogenic induced Changes on the Terrestrial Water Cycle." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/105061.
Full textAbstract:
The land surface and atmosphere interact through complex feedback loops that link energy and water cycles. Effectively characterizing these linkages is critical to modeling weather and climate extremes accurately. Seasonal variability in vegetation growth and human-driven land cover changes (LCC) can alter the biophysical properties of the land surface, which can in turn influence the water cycle. We quantified the impacts of seasonal variability in vegetation growth on land surface energy and water balances using ecosystem-scale eddy covariance and large aperture scintillometer observations. Our results indicated that the monthly precipitation and seasonal vegetation characteristics such as leaf area index, root length, and stomatal resistance are the main factors influencing ecosystem land surface energy and water balances when soil moisture and available energy are not limited. Using a regional-scale climate model, we examined the effect of LCC and irrigation on summer water cycle characteristics. Changes in biophysical properties due to LCC reducing the evapotranspiration, atmospheric moisture, and summer precipitation over the contiguous United States (CONUS). The combined effects of LCC and irrigation indicated a significant drying over the CONUS, with increased duration and decreased intensity of dry spells, and reduced duration, frequency, and intensity of wet spells. Irrigated cropland areas will become drier due to the added effect of low-precipitation wet spells and long periods (3-4% increase) of dry days, whereas rainfed croplands are characterized by intense (1-5% increase), short-duration wet spells and long periods of dry days. An analysis based on future climate change projections indicated that 3–4 °C of warming and an intensified water cycle will occur over the CONUS by the end of the 21st century. The results of this study highlighted the importance of the accurate representation of seasonal vegetation changes and LCC while forecasting present and future climate.Doctor of Philosophy
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Parajuli, Ranjan. "USING CLIMATE MODELS TO PREDICT WATER SUPPLY AND DEMAND IN LAS VEGAS VALLEY: A SYSTEM DYNAMICS APPROACH." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2365.
Full textAbstract:
This study investigated the impact of changing climate and growing population on water supply and demand in one of the most rapidly growing cities in the semi-arid regions of western US, Las Vegas Valley (LVV), Nevada. Future scenarios of supply and demand using climate and hydrological models of Coupled Model Intercomparison Project phase 3 (CMIP3) and a more recent CMIP5 have been evaluated and a comparison of their results has been made. A system dynamics model for LVV was developed with a period of study from 1989 to 2049. For the study area, climate and hydrological data projections for the future period (2013-2049) were obtained from the outputs of 16 Global Climate Models (GCMs) of CMIP3 model ensemble with 3 emission scenarios and that from 37 GCMs of CMIP5 model ensemble with 4 Representative concentration pathways. Population growth forecast by Center for Business and Economic Research (CBER) and prevalent conservation practices by Southern Nevada Water Authority (SNWA) were used for the model. The water availability scenario in the future for LVV in the form of Lake Mead elevation was assessed and the water demand was also predicted. This study found that mean lake elevation for the future period (2013-2049) can go as low as 21.8% lesser than that for the historical period (1989-2012). 59 of 97 projections of CMIP5 models against 27 of 48 projections of CMIP3 models indicated that the future mean lake elevation would be lower than the historical mean. Demand forecasts showed Southern Nevada Water Authority conservation goal for 2035 could be met under prevalent conservation practices. This study can be very useful for the water managers and planners to predict the future water budget, plan accordingly, and make decisions to achieve water sustainability. This study has been performed as a part of the Thriving Earth Exchange (TEX) program to assess the current vulnerability of LVV to drought, and the impact on supply and demand of water resources for the future climate scenarios.