Dissertations / Theses on the topic 'Evolving'
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Coppersmith, Adam. "Evolving community." This title; PDF viewer required Home page for entire collection, 2007. http://archives.udmercy.edu:8080/dspace/handle/10429/9.
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Williams, Nathan Thomas. "Evolving Collections." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/8799.
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My art practice begins with the collecting, processing, and organizing of materials. Through experimentation, I have developed processes centered around a commitment of time and devotion to the plainest beauty of these found materials, their inherent properties, and related systems, making the resulting objects of order possible. Through my application of these personal ordering systems, I strive to bring intrigue and focus to the common and discarded. The process of finding and organizing common surplus materials has given me an understanding of myself, seeing things that may never have occurred were it not for these experiences. This practice has taken what might have been an unhealthy obsession and converted this energy into what I consider a positive outcome and an avenue to living a good productive life.
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Fuchs, Alexander Tinelli C. "Evolving model evolution." [Iowa City, Iowa] : University of Iowa, 2009. http://ir.uiowa.edu/etd/361.
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Christensen, P. A. "Oxygen-evolving photosystems." Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/37971.
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Johnson, Michael Patrick 1971. "Evolving visual routines." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/61533.
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O'Hara, II John Thomas. "Evolving the Suburbs." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83824.
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The single family home is a building type synonymous with residential architecture among many in the United States. The notion that the ideal built character of a dwelling is a private structure, built on private land, and owned by a private entity is as old as that ownership equating to power in human history. Though the houses of today are no longer the literal manifestations of strength seen in the fortifications of feudal castles or wealth seen in the opulence of imperial palaces, the metaphorical implications remain.
It was on these allegories that the Post-WWII housing boom capitalized, using slogans and advertisements meant to invoke the glory and strength of owning a home. They charged that a man was not truly a man until he owned his own home, and that this American Dream can be achieved for surprisingly low prices. Thus the home was commoditized and development after development of ‘single family homes’ were replicated across the country.
70 years later, these structures which were built quickly for cost efficiency, and with a very specific ‘single family’ in mind for their residents are reaching the end of their usable lives. The architecture which replaces or adds to them has significant power to redefine the notion of a single-family home and its surrounding neighborhood. This thesis seeks to understand the current trend of redevelopment in these areas and propose alternate solutions which enrich the built character of the community and expands on the notion of what residential architecture can be.Master of Architecture
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Martin, Andrew Thomas. "The evolving lexicon." Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1481658121&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Kammeyer, Thomas E. "Evolving stochastic grammars /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9907601.
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Lim, Yow Tzu. "Evolving security policies." Thesis, University of York, 2010. http://etheses.whiterose.ac.uk/1612/.
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As computer system size and complexity grow, formulating effective policies require more sophistication. There are many risk factors that need to be considered, some of which may be in conflict. Inevitably, unpredictable circumstances that demand decisions will arise during operation. In some cases an automated response may be imperative; in other cases these may be ill-advised. Manual decisions are often made that override the current policy and serve effectively to redefine it. This matter is further complicated in highly dynamic operational environments like mobile ad-hoc networks, in which the risk factors may be changing continually. Thus, security policies must be able to change and adapt to the operational needs. This study investigates the potential of evolutionary algorithms as a tool in determining the optimal security policies that suit such environments. This thesis reviews some fundamental concepts in related domains. It presents three applications of evolutionary algorithms in solving problems that are of direct relevance. These include the inference of security policies from decision examples, the dynamic adaptation of security policies, and the optimisation of security policies for a specific set of missions. The results show that the inference approaches based on evolutionary algorithms are very promising. The thesis concludes with an evaluation of the work done, the extent to which the work justifies the thesis hypothesis and some possible directions on how evolutionary algorithms can be applied to address a wider range of relevant problems in the domain of concern.
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Fuchs, Alexander. "Evolving model evolution." Diss., University of Iowa, 2009. https://ir.uiowa.edu/etd/361.
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Automated theorem proving is a method to establish or disprove logical theorems. While these can be theorems in the classical mathematical sense, we are more concerned with logical encodings of properties of algorithms, hardware and software. Especially in the area of hardware verification, propositional logic is used widely in industry. Satisfiability Module Theories (SMT) is a set of logics which extend propositional logic with theories relevant for specific application domains. In particular, software verification has received much attention, and efficient algorithms have been devised for reasoning over arithmetic and data types. Built-in support for theories by decision procedures is often significantly more efficient than reductions to propositional logic (SAT). Most efficient SAT solvers are based on the DPLL architecture, which is also the basis for most efficient SMT solvers. The main shortcoming of both kinds of logics is the weak support for non-ground reasoning, which noticeably limits the applicability to real world systems.
The Model Evolution Calculus (ME) was devised as a lifting of the DPLL architecture from the propositional setting to full first-order logic. In previous work, we created the solver Darwin as an implementation of ME, and showed how to adapt improvements from the DPLL setting. The first half of this thesis is concerned with ME and Darwin. First, we lift a further crucial ingredient of SAT and SMT solvers, lemma-learning, to Darwin and evaluate its benefits. Then, we show how to use Darwin for finite model finding, and how this application benefits from lemma-learning.
In the second half of the thesis we present Model Evolution with Linear Integer Arithmetic (MELIA), a calculus combining function-free first-order logic with linear integer arithmetic (LIA). MELIA is based on ME and supports similar inference rules and redundancy criteria. We prove the correctness of the calculus, and show how to obtain complete proof procedures and decision procedures for some interesting classes of MELIA's logic. Finally, we explain in detail how MELIA can be implemented efficiently based on the techniques employed in SMT solvers and Darwin.
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Ridlen, Michael Traver. "Prud'hon's evolving classicism." Diss., University of Iowa, 2017. https://ir.uiowa.edu/etd/5614.
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Attempting to make sense of the oeuvre of Prud’hon in 1876, Edmond de Goncourt in his Catalogue Raisonné de Prud’hon contrasts Prud’hon’s paintings with the predominant art of David and his students. He describes Prud’hon as an isolated romantic artist, full of elegance, going against the virile masculine academic traditions of his day. Goncourt sees in Prud’hon the epitome of an erotic classicism, which he considers unique for his time. I seek to demonstrate that Prud’hon’s embrace of classicism reflects and propels a variety of contexts from the literary, aesthetic, philosophical, and cultural developments of his time.
The significance of poignant upheaval and the political change from the ancien regime through the Revolution and the Empire had a considerable impact on the various moments examined in my dissertation. I use selected examples from his works and those of his contemporaries to serve as case studies to reveal key moments in the development of his oeuvre.
Prud’hon’s oeuvre is vast, but my dissertation will highlight case studies from 1770-1815. I have analyzed central concepts of this period’s aesthetic and philosophical ideals, especially the philosophic treatises by French Enlightenment thinkers such as Rousseau and Diderot, and by classicists like Winckelmann and Quatremère de Quincy. Prud’hon’s transformations were also clearly impacted by the historical reality of the French Revolution and Empire.
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Quiroz, Juan C. "Interactively evolving user interfaces." abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1442877.
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Lewis, Damon Marcus 1977. "Evolving efficient airline schedules." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/8561.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.Includes bibliographical references (p. 59).
This project is to solve the fleet scheduling problem for a large airline. This requires matching each fight in a schedule to a plane in the fleet that will fly the scheduled flight on a particular day. This thesis shows how to use the network flow model of a flight schedule in order to find the smallest fleet required to fly a schedule without dropping any flights. This is done by pruning the whole network to a smaller set of more relevant arcs. It is also the goal of the project to perform these tasks without requiring a large powerful computer or workstation.
by Damon Marcus Lewis.
M.Eng.
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Guo, AnYuan 1976. "Evolving language among agents." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80225.
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Simmons, Katrina Anne. "Evolving with the sun." Thesis, Virginia Polytechnic Institute and State University, 1996. http://hdl.handle.net/10919/53427.
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From the beginning of architectural history, climate has been a major controlling force in building design. A building’s envelope must keep out the elements and minimize great temperature changes as well as admit light. Massive masonry walls were employed as thermal storage to alleviate excessive temperature swings. The thickness of these thermal barriers affected lighting conditions within the structure. Sunshine was prevented from reaching the interior. Instead, the daylight was softened and diffused as it reflected and bounced along the fenestration’s thick walls.
Not only was the skin used for thermal control, it also provided illumination for the interior. Daylight was the primary method of illumination which was supplemented with candles and oil lamps. Because the skin of a building was the only mediator between the interior and exterior climates, all perforations had to be carefully considered.
Buildings were designed to make use of the daylight. Activities which needed illumination were limited to daytime hours. Rooms were placed along the exterior walls of buildings to make the most of the daylight illumination. Building depth was restricted by how deeply daylight could penetrate into a room. Interior courtyards were implemented to illuminate interior spaces that could not be accommodated by exterior windows. People who wanted to remain within the confines of their building but needed large quantities of light to complete their various tasks would gather here. The courtyards lent a sense of community to its inhabitants. People were able to communicate with one another both verbally and visually.
Daylight did more than illuminate interiors. It provided a constantly changing visual atmosphere. The light which passed through the fenestrations reflected the ever-changing movements of the sun and clouds. Without looking out a window, one could sense the moods of the day as well as the passage of time, the atmosphere within was always changing.
With the advent of the Industrial Revolution, building design was changed. Climate could be ignored in building design. Inventions such as electric lighting and forced air circulation replaced windows. Rooms no longer depended on their proximity to the exterior face for illumination. Large workspaces could be partitioned into small individual offices. With smaller space and individual offices, employees no longer had direct access to one another. The uniform electric lighting produced a static atmosphere. The visual atmosphere and the sense of community that came from courtyard design was lost.
Was it really necessary to lose the subtle qualities produced by ancient building methods just to have modern amenities? Was there not some way to use technology to enhance those ancient qualities? At a time when most architects shunned the old ways to embrace the new technology, three architects stood out because they chose to incorporate the new building methods with the old. The three architects were Frank Lloyd Wright, Louis Kahn and Alvar Aalto. These men were able to design buildings based on the climatic conditions of a site and integrate those designs with twentieth century technology.Master of Architecture
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Hilder, James Alan. "Evolving variability tolerant logic." Thesis, University of York, 2010. http://etheses.whiterose.ac.uk/1334/.
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Intrinsic variability occurs between individual MOSFET transistors caused by atomic-scale differences in the construction of devices. The impact of this variability will become a major issue in future circuit design as the devices scale below 50nm. In this thesis, the background to the causes and effects of intrinsic variability, in particular that of random dopant placement and line-edge roughness, is discuss. A system is developed which uses a genetic algorithm to attempt to optimise the dimensions of transistors within standard-cell libraries, with the aim of improving performance and reducing the impact of intrinsic variability in terms of the effect on circuit delay and power consumption. The genetic algorithm uses a multi-objective fitness function to allow a number of circuit characteristics to be considered in the evolution process. The system is tested using different standard-cell libraries from open-source and commercial providers, with developments and alterations to the system that have been made throughout the course of the experiments discussed. Comparisons of the performance with other optimisation techniques, hill climbing and simulated-annealing, are discussed. The optimisation process concludes with the use of e-Science techniques to allow for detailed statistical analysis of the evolved designs on high-performance computing clusters. The observed results for two-input logic gates demonstrate that the technique can be effective in the reduction of statistical spread in the delay and power consumption of circuits subject to intrinsic variability. The thesis finishes with the investigation of larger circuits which are assembled from the optimised cells. A proposed design methodology is introduced, in which the processes of logic design are broken into small blocks, each of which uses techniques from evolutionary computation to improve performance. This includes an investigation into the application of a multi-objective fitness function to improve the performance of logic circuits evolved using Cartesian Genetic Programming, which produces designs for logic multiplier and display driver circuits which are competitive with human-produced designs and other evolved designs. These designs are assessed for their variability tolerance, with the multiplier circuit demonstrating an improvement in delay variability.
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Vega, López Iné s. Fernando. "Summarizing time-evolving data." Diss., The University of Arizona, 2004. http://hdl.handle.net/10150/290088.
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We live in a highly dynamic environment where we have learned to appreciate time as a very important aspect in our lives. The world, as we know it, is not the same as it was yesterday and it will not be the same tomorrow. Things evolve over time. As we try to better understand our environment, we need to model this continuous change. To satisfy this need, the research community has developed temporal database systems. Summarizing time-evolving data is a challenging problem. Not only is this problem challenging because of the large size of the data sets usually involved but also because the temporal ordering and validity of every entry in the database must be considered. In this dissertation we present effective and efficient solutions to the problem of summarizing time-evolving data from two different perspectives. The first perspective considers capturing the collective behavior of temporal data in a process known as temporal aggregation. For this, we propose a model that reduces the evaluation of temporal aggregation queries to the problem of selecting qualifying tuples and grouping these tuples into collections to which an aggregate function is to be applied. In addition, we propose IO efficient algorithms for the evaluation of temporal aggregation queries. The second perspective we study is aimed toward the detection of individual entities in the database whose temporal behavior (evolution) matches a given pattern. The process of matching the temporal evolution of an entry in the database to a query pattern is known as similarity search. To address this problem, we propose a new indexing paradigm called Skyline Index and a new and compact representation of time series called Self COntained Bit Encoding (SCoBE). The techniques proposed in this dissertation provide significant performance improvements over the current state-of-the-art. Our empirical evidence shows that the proposed algorithms for the evaluation of temporal aggregation queries significantly outperform previous approaches. We experimentally show that the Skyline Index can be coupled with the state of the art dimensionality reduction techniques and significantly improve the performance on the evaluation of similarity search queries. Similarly, we show that SCoBE consistently outperforms previously proposed transformations of time series data for the evaluation of similarity search queries under a variety of scenarios.
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Degrand, Elisabeth. "Evolving Chemical Reaction Networks." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-257491.
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One goal of synthetic biology is to implement useful functions with biochemical reactions, either by reprogramming living cells or programming artificial vesicles. In this perspective, we consider Chemical Reaction Networks (CRNs) as a programming language. Recent work has shown that continuous CRNs with their dynamics described by ordinary differential equations are Turing complete. That means that any function over the reals that is computable by a Turing machine in arbitrary precision, can be computed by a CRN over a finite set of molecular species. The proof uses an algorithm which, given a computable function presented as the solution of a PIVP (PolynomialInitial Values Problem), generates a finite CRN to implement it. In the generated CRNs, the molecular concentrations play the role of information carriers, similarly to proteins in cells. In this Master’s Thesis, we investigate an approach based on an evolutionary algorithm to build a continuous CRN that approximates a real function given a finite set of the values of the function. The idea is to use a two-level parallel genetic algorithm. A first algorithm is used to evolve the structure of the network, while the other one enables us to optimize the parameters of the CRNs at each step. We compare the CRNs generated by our method on different functions. The CRNs found by evolution often give good results with quite unexpected solutions.Ett mål med syntetisk biologi är att genomföra användbara funktioner med biokemiska reaktioner, antingen genom omprogrammering av levande celler eller programmering av artificiella vesiklar. I detta perspektiv anser vi Chemical Reaction Networks (CRNs) som ett programmeringsspråk. Det senaste arbetet har visat att kontinuerliga CRNs med dynamik som beskrivs av vanliga differentialekvationer är Turingkompletta. Det betyder att en funktion över de realla talen som kan beräknas av en Turing-maskin i godtycklig precision, kan beräknas av en CRN över en ändlig uppsättning molekylära arter. Beviset använder en algoritm som, givet en beräkningsbar funktion som presenteras som lösningen av ett PIVP (Polynomial Initial Values Problem), genererar en ändlig CRN för att implementera den. I de genererade CRN:erna spelar molekylkoncentrationerna rollen som informationsbärare, på samma sätt som proteiner i celler. I detta examensarbete undersöker vi ett tillvägagångssätt baserat på en evolutionär algoritm för att bygga en kontinuerlig CRN som approximerar en verklig funktion med en ändlig uppsättning av värden för funktionen. Tanken är att använda parallell genetisk algoritm i två nivåer. En första algoritm används för att utveckla nätets struktur, medan den andra möjliggör att optimera parametrarna för CRN:erna vid varje steg. Vi jämför de CRN som genereras av vår metod på olika funktioner. De CRN som hittas av evolutionen ger ofta bra resultat med ganska oväntade lösningar.
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Hayes, Susan. "Evolving a Theatre of Truth." VCU Scholars Compass, 2006. http://hdl.handle.net/10156/1540.
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Gemulla, Rainer. "Sampling Algorithms for Evolving Datasets." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1224861856184-11644.
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Perhaps the most flexible synopsis of a database is a uniform random sample of the data; such samples are widely used to speed up the processing of analytic queries and data-mining tasks, to enhance query optimization, and to facilitate information integration. Most of the existing work on database sampling focuses on how to create or exploit a random sample of a static database, that is, a database that does not change over time. The assumption of a static database, however, severely limits the applicability of these techniques in practice, where data is often not static but continuously evolving. In order to maintain the statistical validity of the sample, any changes to the database have to be appropriately reflected in the sample. In this thesis, we study efficient methods for incrementally maintaining a uniform random sample of the items in a dataset in the presence of an arbitrary sequence of insertions, updates, and deletions. We consider instances of the maintenance problem that arise when sampling from an evolving set, from an evolving multiset, from the distinct items in an evolving multiset, or from a sliding window over a data stream. Our algorithms completely avoid any accesses to the base data and can be several orders of magnitude faster than algorithms that do rely on such expensive accesses. The improved efficiency of our algorithms comes at virtually no cost: the resulting samples are provably uniform and only a small amount of auxiliary information is associated with the sample. We show that the auxiliary information not only facilitates efficient maintenance, but it can also be exploited to derive unbiased, low-variance estimators for counts, sums, averages, and the number of distinct items in the underlying dataset. In addition to sample maintenance, we discuss methods that greatly improve the flexibility of random sampling from a system's point of view. More specifically, we initiate the study of algorithms that resize a random sample upwards or downwards. Our resizing algorithms can be exploited to dynamically control the size of the sample when the dataset grows or shrinks; they facilitate resource management and help to avoid under- or oversized samples. Furthermore, in large-scale databases with data being distributed across several remote locations, it is usually infeasible to reconstruct the entire dataset for the purpose of sampling. To address this problem, we provide efficient algorithms that directly combine the local samples maintained at each location into a sample of the global dataset. We also consider a more general problem, where the global dataset is defined as an arbitrary set or multiset expression involving the local datasets, and provide efficient solutions based on hashing.
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Salama, Rameri. "On evolving modular neural networks." University of Western Australia. Dept. of Computer Science, 2000. http://theses.library.uwa.edu.au/adt-WU2003.0011.
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The basis of this thesis is the presumption that while neural networks are useful structures that can be used to model complex, highly non-linear systems, current methods of training the neural networks are inadequate in some problem domains. Genetic algorithms have been used to optimise both the weights and architectures of neural networks, but these approaches do not treat the neural network in a sensible manner. In this thesis, I define the basis of computation within a neural network as a single neuron and its associated input connections. Sets of these neurons, stored in a matrix representation, comprise the building blocks that are transferred during one or more epochs of a genetic algorithm. I develop the concept of a Neural Building Block and two new genetic algorithms are created that utilise this concept. The first genetic algorithm utilises the micro neural building block (micro-NBB); a unit consisting of one or more neurons and their input connections. The micro-NBB is a unit that is transmitted through the process of crossover and hence requires the introduction of a new crossover operator. However the micro NBB can not be stored as a reusable component and must exist only as the product of the crossover operator. The macro neural building block (macro-NBB) is utilised in the second genetic algorithm, and encapsulates the idea that fit neural networks contain fit sub-networks, that need to be preserved across multiple epochs. A macro-NBB is a micro-NBB that exists across multiple epochs. Macro-NBBs must exist across multiple epochs, and this necessitates the use of a genetic store, and a new operator to introduce macro-NBBs back into the population at random intervals. Once the theoretical presentation is completed the newly developed genetic algorithms are used to evolve weights for a variety of architectures of neural networks to demonstrate the feasibility of the approach. Comparison of the new genetic algorithm with other approaches is very favourable on two problems: a multiplexer problem and a robot control problem.
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Barrier, Marianne. "Selection and Rapidly-Evolving Genes." NCSU, 2002. http://www.lib.ncsu.edu/theses/available/etd-08162002-062003/.
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Rapidly-evolving genes which exhibit an increased rate of amino acid substitution, resulting in greater amino acid sequence difference, often provide insight into the mechanisms of adaptation and speciation. In this dissertation research, the evolution of rapidly-evolving genes under selection was examined. Homologues to the Arabidopsis APETALA3 (ASAP3/TM6) and APETALA1 (ASAP1) floral regulatory genes and the CHLOROPHYLL A/B BINDING PROTEIN9 (ASCAB9) photosynthetic structural gene were isolated from species in the Hawaiian silversword alliance, a premier example of plant adaptive radiation. The two floral homeotic genes are found in duplicate copies within members of the Hawaiian silversword alliance and appear to have arisen as a result of interspecific hybridization between two North American tarweed species. Molecular phylogenetic analyses suggest that the interspecific hybridization event involved members of lineages that include Carlquistia muirii (and perhaps Harmonia nutans) and Anisocarpus scabridus. Next, rates of regulatory and structural gene evolution in the Hawaiian species were compared to those in related species of North American tarweeds. Molecular evolutionary analyses indicate significant increases in nonsynonymous relative to synonymous nucleotide substitution rates in the ASAP3/TM6 and ASAP1 regulatory genes in the rapidly evolving Hawaiian species. By contrast, no general increase is evident in neutral mutation rates for these loci in the Hawaiian species. Finally, a group of potential rapidly-evolving genes were identified in Arabidopsis using a powerful evolutionary expressed sequence tag (EST) approach. One indicator of adaptive selection at the molecular level is an excess of amino acid replacement fixed differences per replacement site relative to the number of silent fixed differences per silent site (w = Ka/Ks). The evolutionary EST approach was used to estimate the distribution of w among 304 orthologous loci between Arabidopsis thaliana and Arabidopsis lyrata to identify genes potentially involved in the adaptive divergence between these two Brassicaceae species. Twenty-one of 304 genes (7%) were found to have an estimated w > 1 and are candidates for genes associated with adaptive divergence. A hierarchical Bayesian analysis of protein coding region evolution within and between species also indicates that the selection intensities of these genes are elevated compared to typical Arabidopsis thaliana nuclear loci.
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Seabrook, Graham. "Evolving Robofish using Genetic Algorithms /." Leeds : University of Leeds, School of Computer Studies, 2008. http://www.comp.leeds.ac.uk/fyproj/reports/0708/Seabrook.pdf.
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Parsons, Mark. "Mathematical modelling of evolving networks." Thesis, University of Reading, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.590673.
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Network theory is a long standing, rapidly changing and highly motivated field. However, historically its results have been centred on static networks, leaving the area of evolving networks relatively less explored. In this thesis we draw from those existing results and extend them to the case of evolving networks to develop new analytical tools and representations. We do this through the introduction of an importance, or activity, metric for evolving networks, and the creation of a general framework for their models, allowing us to easily define, represent and classify them. We identify observable network properties and seek to predict the long term network structure of these modelled evolving networks. We find that networks can have a wide range of equilibria, even within the same model, from those devoid of network activity, to those exhibiting quasi-periodic network structure. These different equilibria within models are found to arise from chosen parameter values, highlighting the importance of their estimation. The properties upon which these models are based are often neglected for simplicity, however the application of our models to existing data proves their existence, and the significant variety of equilibria between network models shows us how important these properties are.
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Orr, Ewan. "Evolving Turing's Artificial Neural Networks." Thesis, University of Canterbury. Department of Physics and Astronomy, 2010. http://hdl.handle.net/10092/4620.
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Our project uses ideas first presented by Alan Turing. Turing's immense contribution to mathematics and computer science is widely known, but his pioneering work in artificial intelligence is relatively unknown. In the late 1940s Turing introduced discrete Boolean artificial neural networks and, it has been argued that, he suggested that these networks be trained via evolutionary algorithms. Both artificial neural networks and evolutionary algorithms are active fields of research. Turing's networks are very basic yet capable of complex tasks such as processing sequential input; consequently, they are an excellent model for investigating the application of evolutionary algorithms to artificial neural networks. We define an example of these networks using sequential input and output, and we devise evolutionary algorithms that train these networks. Our networks are discrete Boolean networks where every 'neuron' either performs NAND or identity, and they can represent any function that maps one sequence of bit strings to another. Our algorithms use supervised learning to discover networks that represent such functions. That is, when searching for a network that represents a particular function our algorithms use input-output pairs of that function as examples to aid the discovery of solution networks. To test our ideas we encode our networks and implement the algorithms in a computer program. Using this program we investigate the performance of our networks and algorithms on simple problems such as searching for networks that realize the parity function and the multiplexer function. This investigation includes the construction and testing of an intricate crossover operator. Because our networks are composed of simple 'neurons' they are a suitable test-bed for novel training schemes. To improve our evolutionary algorithms for some problems we employ the symmetry of the problem to reduce its search space. We devise and test a means of using subgroups of the group of permutation of inputs of a function to aid evolutionary searches search for networks that represent that function. In particular, we employ the action of the permutation group S₂ to 'cut down' the search space when we search for networks that represent functions such as parity.
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Lekkas, Stavros. "Evolving intelligent intrusion detection systems." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503075.
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The vast majority of existing Intrusion Detection Systems incorporates static knowledge bases, which contain information about specific attack patterns. Although such knowledge bases can gradually expand, yet they have required the close maintenance of an expert, letting alone the possibility that the knowledge base might overload and tinally run over. Furthermore, most of the existing quantitative methods for intrusion detection require the data records to be processed in offline mode, as a batch. Unfortunately this allows only a snapshot of the actual domain to be analysed. On top of that, should new data records become available they require cost-sensitive calculations due to the fact that re-learning is ineffective for real-time applications. The prospective application of evolving nature-inspired intelligent behavior in conjunction with network intrusion detection is an attractive field which overcomes these problems, but which contains open questions remaining to be answered. A standalone Network Intrusion Detection System, which is capabk of evolving its knowledge structure and parameters in order to prevent both known and novel intrusions. is still not available. Initially, this thesis reviews a methodology for evolving fuzzy classification. which allows data to be processed in online mode by recursively modifying a fuzzy rule base on a per-sample basis. The incremental adaptation is gradually developed by the int1uence of the input data, which arrive from a data stream in succession. Recent studies have shown that the eClass algorithms are a promising elucidation since they have been extensively used for control applications and are also suitable for real-time classification tasks. such as fault detection, diagnosis, robotic navigation ctc. Finally, it is revealed that the relative eClass architecture can be further improved in terms of the predictive accuracy and that it can be effectively applied on behalf of network diagnostics. The improved algorithm is finally compared to others and seems to outperform many well-known methods and to be adequately competent.
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Ren, Chenghui, and 任成會. "Algorithms for evolving graph analysis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/197105.
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In many applications, entities and their relationships are represented by graphs. Examples include social networks (users and friendship), the WWW (web pages and hyperlinks) and bibliographic networks (authors and co-authorship). In a dynamic world, information changes and so the graphs representing the information evolve with time. For example, a Facebook link between two friends is established, or a hyperlink is added to a web page. We propose that historical graph-structured data be archived for analytical processing. We call a historical
evolving graph sequence an EGS.
We study the problem of efficient query processing on an EGS, which finds many applications that lead to interesting evolving graph analysis. To solve the problem, we propose a solution framework called FVF and a cluster-based LU decomposition algorithm called CLUDE, which can evaluate queries efficiently to support EGS analysis.
The Find-Verify-and-Fix (FVF) framework applies to a wide range of queries. We demonstrate how some important graph measures, including shortest-path distance, closeness centrality and graph centrality, can be efficiently computed from EGSs using FVF. Since an EGS generally contains numerous large graphs, we also discuss several compact storage models that support our FVF framework. Through extensive experiments on both real and synthetic datasets, we show that our FVF framework is highly efficient in EGS query processing.
A graph can be conveniently modeled by a matrix from which various quantitative measures are derived like PageRank and SALSA and Personalized PageRank and Random Walk with Restart. To compute these measures, linear systems of the form Ax = b, where A is a matrix that captures a graph's structure, need to be solved. To facilitate solving the linear system, the matrix A is often decomposed into two triangular matrices (L and U). In a dynamic world, the graph that models it changes with time and thus is the matrix A that represents the graph. We consider a sequence of evolving graphs and its associated sequence of evolving matrices. We study how LU-decomposition should be done over the sequence so that (1) the decomposition is efficient and (2) the resulting LU matrices best preserve the sparsity of the matrices A's (i.e., the number of extra non-zero entries introduced in L and U are minimized). We propose a cluster-based algorithm CLUDE for solving the problem. Through an experimental study, we show that CLUDE is about an order of magnitude faster than the traditional incremental update algorithm. The number of extra non-zero entries introduced by CLUDE is also about an order of magnitude fewer than that of the traditional algorithm. CLUDE is thus an efficient algorithm for LU decomposition that produces high-quality LU matrices over an evolving matrix sequence.published_or_final_version
Computer Science
Doctoral
Doctor of Philosophy
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Shaw, Hazel Anne. "Automated test of evolving software." Thesis, University of Bedfordshire, 2005. http://hdl.handle.net/10547/305743.
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Computers and the software they run are pervasive, yet released software is often unreliable, which has many consequences. Loss of time and earnings can be caused by application software (such as word processors) behaving incorrectly or crashing. Serious disruption can occur as in the l4th August 2003 blackouts in North East USA and Canadal, or serious injury or death can be caused as in the Therac-25 overdose incidents. One way to improve the quality of software is to test it thoroughly. However, software testing is time consuming, the resources, capabilities and skills needed to carry it out are often not available and the time required is often curtailed because of pressures to meet delivery deadlines3. Automation should allow more thorough testing in the time available and improve the quality of delivered software, but there are some problems with automation that this research addresses. Firstly, it is difficult to determine ifthe system under test (SUT) has passed or failed a test. This is known as the oracle problem4 and is often ignored in software testing research. Secondly, many software development organisations use an iterative and incremental process, known as evolutionary development, to write software. Following release, software continues evolving as customers demand new features and improvements to existing ones5. This evolution means that automated test suites must be maintained throughout the life ofthe software. A contribution of this research is a methodology that addresses automatic generation of the test cases, execution of the test cases and evaluation of the outcomes from running each test. "Predecessor" software is used to solve the oracle problem. This is software that already exists, such as a previous version of evolving software, or software from a different vendor that solves the same, or similar, problems. However, the resulting oracle is assumed not be perfect, so rules are defined in an interface, which are used by the evaluator in the test evaluation stage to handle the expected differences. The interface also specifies functional inputs and outputs to the SUT. An algorithm has been developed that creates a Markov Chain Transition Matrix (MCTM) model of the SUT from the interface. Tests are then generated automatically by making a random walk of the MCTM. This means that instead of maintaining a large suite of tests, or a large model of the SUT, only the interface needs to be maintained.
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Deakin, Anthony Grayham. "Evolving strategies with genetic programming." Thesis, University of Liverpool, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272651.
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Zhang, Yuyuan. "Evolving fault tolerant robotic controllers." Thesis, University of York, 2018. http://etheses.whiterose.ac.uk/22334/.
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Fault tolerant control and evolutionary algorithms are two different research areas. However with the development of artificial intelligence, evolutionary algorithms have demonstrated competitive performance compared to traditional approaches for the optimisation task. For this reason, the combination of fault tolerant control and evolutionary algorithms has become a new research topic with the evolving of controllers so as to achieve different fault tolerant control schemes. However most of the controller evolution tasks are based on the optimisation of controller parameters so as to achieve the fault tolerant control, so structure optimisation based evolutionary algorithm approaches have not been investigated as the same level as parameter optimisation approaches. For this reason, this thesis investigates whether structure optimisation based evolutionary algorithm approaches could be implemented into a robot sensor fault tolerant control scheme based on the phototaxis task in addition to just parameter optimisation, and explores whether controller structure optimisation could demonstrate potential benefit in a greater degree than just controller parameter optimisation. This thesis presents a new multi-objective optimisation algorithm in the structure optimisation level called Multi-objective Cartesian Genetic Programming, which is created based on Cartesian Genetic Programming and Non-dominated Sorting Genetic Algorithm 2, in terms of NeuroEvolution based robotic controller optimisation. In order to solve two main problems during the algorithm development, this thesis investigates the benefit of genetic redundancy as well as preserving neutral genetic drift in order to solve the random neighbour pick problem during crowding fill for survival selection and investigates how hyper-volume indicator is employed to measure the multi-objective optimisation algorithm performance in order to assess the convergence for Multi-objective Cartesian Genetic Programming. Furthermore, this thesis compares Multi-objective Cartesian Genetic Programming with Non-dominated Sorting Genetic Algorithm 2 for their evolution performance and investigates how Multi-objective Cartesian Genetic Programming could be performing for a more difficult fault tolerant control scenario besides the basic one, which further demonstrates the benefit of utilising structure optimisation based evolutionary algorithm approach for robotic fault tolerant control.
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Woolever, Jason R. (Jason Richard) 1978. "Evolving a bridge bidding system." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86753.
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Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (p. 61-62).
by Jason R. Woolever.
M.Eng.
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Houston, Brad. "Transfer of an evolving technology." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/34715.
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Thesis (S.M.)--Massachusetts Institute of Technology, Sloan School of Management; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering; in conjunction with the Leaders for Manufacturing Program at the Massachusetts Institute of Technology, 1995.Includes bibliographical references.
This thesis follows the transfer of a thin film from development to manufacturing. Problems of differences in equipment and differences in manufacturing methods were overcome to complete the transfer. The film was characterized using UV-Visible, FTIR, and Raman spectroscopy. Hydrogen forward scattering, surface bead angle, and atomic force microscopy were also employed. A series of experiments was conducted to: 1) Analyze the impact of deposition parameters on the performance of the film. 2) Match the performance of films produced in the manufacturing site to the performance of films produced in the development site. Both the development and manufacturing sites were acquired by a new company during the period of this transfer. The cultures of the development and manufacturing sites had not merged before this occurred. This fact, coupled with subsequent reorganization undertaken by the new management, has the potential to slow product introductions. The transfer of this film was successful despite the organizational upheaval occurring at the same time. Three factors contributed to this success: 1) The development engineer stayed with the process throughout the transfer to manufacturing. 2) The collaboration of upstream manufacturing steps integrated the new process with the existing line. 3) Early involvement of manufacturing speeded acceptance and lessened training costs. Recommendations to better link the manufacturing and technology development groups, based on observations made during work on the film transfer, are presented for management's consideration. Key among these is the establishment of common goals and the building of a communication infrastructure between the two sites.
by Brad Houston.
S.M.
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Serra, Marco 1968. "Evolving the product development process." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/91755.
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Karam, Joseph Ghaleb. "Effectiveness analysis of evolving systems." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/15319.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
Bibliography: leaf 97.
by Joseph Ghaleb Karam.
M.S.
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Tyska, Carvalho Jônata. "Adaptive behaviour in evolving robots." Thesis, University of Plymouth, 2017. http://hdl.handle.net/10026.1/10547.
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In this thesis, the evolution of adaptive behaviour in artificial agents is studied. More specifically, two types of adaptive behaviours are studied: articulated and cognitive ones. Chapter 1 presents a general introduction together with a brief presentation of the research area of this thesis, its main goals and a brief overview of the experimental studies done, the results and conclusions obtained. On chapter 2, I briefly present some promising methods that automatically generate robot controllers and/or body plans and potentially could help in the development of adaptive robots. Among these methods I present in details evolutionary robotics, a method inspired on natural evolution, and the biological background regarding adaptive behaviours in biological organisms, which provided inspiration for the studies presented in this thesis. On chapter 3, I present a detailed study regarding the evolution of articulated behaviours, i.e., behaviours that are organized in functional sub-parts, and that are combined and used in a sequential and context-dependent way, regardless if there is a structural division in the robot controller or not. The experiments performed with a single goal task, a cleaning task, showed that it is possible to evolve articulated behaviours even in this condition and without structural division of the robot controller. Also the analysis of the results showed that this type of integrated modular behaviours brought performance advantages compared to structural divided controllers. Analysis of robots' behaviours helped to clarify that the evolution of this type of behaviour depended on the characteristics of the neural network controllers and the robot's sensorimotor capacities, that in turn defined the capacity of the robot to generate opportunity for actions, which in psychological literature is often called affordances. In chapter 4, a study seeking to understand the role of reactive strategies in the evolution of cognitive solutions, i.e. those capable of integrating information over time encoding it on internal states that will regulate the robot's behaviour in the future, is presented. More specifically I tried to understand whether the existence of sub-optimal reactive strategies prevent the development of cognitive solutions, or they can promote the evolution of solutions capable of combining reactive strategies and the use of internal information for solving a response delayed task, the double t-maze. The results obtained showed that reactive strategies capable of offloading cognitive work to the agent/environmental relation can promote, rather than prevent the evolution of solutions relying on internal information. The analysis of these results clarified how these two mechanisms interact producing a hybrid superior and robust solution for the delayed response task.
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Watson, Roger. "Evolving trends in Open Access." Universität Leipzig, 2019. https://ul.qucosa.de/id/qucosa%3A33909.
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With the growth of open access publishing there has been a concomitant growth in the number of predatory publishers. This article considers why open access has arisen and the various models under which it operates before considering the nature of predatory publishers and what can be done to stop them.
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Taliotis, Anastasios S. "Evolving Geometries in General Relativity." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1274838401.
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Leuthäuser, Max. "Pure Embedding of Evolving Objects." International Academy, Research, and Industry Association, 2017. https://tud.qucosa.de/id/qucosa%3A70692.
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Scripting languages are extraordinarily popular due to their very flexible object model. Dynamic extensions (i.e., adding, removing and manipulating behavior and state) allow for the evolution and adaption of objects to context changes at runtime. Introducing this flexibility into a statically typed, object-oriented language would improve programmability and separation of concerns beyond the level of what one could usually gain with inheritance, mixins, traits or manually adapted designpatterns. They often lead to object-schizophrenia or the need for hand-crafted, additional management code. Although there were already attempts bringing flexible objects into statically typed languages with the benefits of an explicitly crafted core calculus or type system, they need their own compiler and tooling which limits the usability, e.g., when dealing with existing legacy code. This work presents an embedding of dynamically evolving objects via a lightweight library approach, which is pure in the sense, that there is no need for a specific compiler or tooling. It is written in Scala, which is both a modern object-oriented and functional programming language. Our approach is promising to solve practical problems arising in the area of dynamical extensibility and adaption like role-based programming.
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Alphonse, Amal. "Parabolic PDEs on evolving spaces." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/77658/.
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This thesis is concerned with the well-posedness of solutions to certain linear and nonlinear parabolic PDEs on evolving spaces. We first present an abstract framework for the formulation and well-posedness of linear parabolic PDEs on abstract evolving Hilbert spaces. We introduce new function spaces and a notion of a weak time derivative called the weak material derivative for this purpose. We apply this general theory to moving hypersurfaces and Sobolev spaces and study four different linear problems including a coupled bulk-surface system and a dynamical boundary problem. Then we formulate a Stefan problem itself on an evolving surface and consider weak solutions given integrable data through the enthalpy approach, using a generalisation to the Banach space setting of the function spaces introduced in the abstract framework. We finish by studying a nonlocal problem: a porous medium equation with a fractional diffusion posed on an evolving surface and we prove well-posedness for bounded initial data.
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Raybould, Amy Jean. "The history of evolving economics /." Lynchburg, VA : Liberty University, 2007. http://digitalcommons.liberty.edu.
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Suvanaphen, Edward. "The visualization of evolving searches." Thesis, University of Kent, 2006. https://kar.kent.ac.uk/24026/.
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Marsh, Randal Charles. "Evolving Art in Junior High." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3872.
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A junior high teacher and artist altered the curriculum of his Art Foundations II course and his own artistic practice in response to complexity thinking. This teacher-artist-researcher uses the arts-based methodology a/r/tography to make meaning of the relationship between his art and pedagogy. The a/r/tographer explains the impact of complexity on the philosophy of education, a/r/tography as a methodology, and the meaning making that occurred are included. Evolution was used as a methodology for art making and as constraint for developing artworks in the classroom and in the author's own art. The teacher-artist-researcher conceptualizes art as an emergent complex cultural practice that evolves over time. He argues that artists, teachers, consumers, and students are implicated in the evolution of art.
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Linker, Groisman Amitai Samuel. "Contact processes on evolving environments." Tesis, Universidad de Chile, 2019. http://repositorio.uchile.cl/handle/2250/170302.
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Tesis para optar al grado de Doctor en Ciencias de la Ingeniería, Mención Modelación MatemáticaEl Proceso de Contacto es un proceso de Markov introducido por Ted Harris en 1974 como un modelo de propagación de infecciones en una red. En este modelo, la red está conformada por individuos que, de estar infectados, pueden recuperarse de la enfermedad o propagarla a vecinos sanos. A pesar de ser un modelo muy simple, el Proceso de Contacto ha sido estudiado en detalle durante los últimos cuarenta años, debido a su capacidad de reflejar algunas de las características más notables de las enfermedades infecciosas, tales como una fuerte dependencia de su comportamiento sobre la red, y la existencia de un valor crítico para su tasa de infección que divide las enfermedades en ``débiles'' y ``fuertes'', donde las primeras mueren rápidamente, mientras que las segundas sobreviven por largos períodos de tiempo. Desde los inicios del estudio de este proceso, se ha dedicado una cantidad de esfuerzo considerable a intentar comprender cómo este es afectado por las características de la red subyacente. Sin embargo, en todos estos esfuerzos se ha considerado que la red es estática en el tiempo, mientras que las redes observadas en la realidad son dinámicas por naturaleza, un aspecto fundamental que ha recibido escasa atención. Esta tesis consiste de tres trabajos relacionados con este tema: En el primer problema estudiamos el Proceso de Contacto sobre un grafo aleatorio finito de escala libre, al cual dotamos de una dinámica estacionaria en que cada vértice actualiza todas sus conexiones de forma simultánea a una tasa que depende de su grado esperado. En este trabajo identificamos y analizamos cuatro posibles estrategias con las cuales la infección puede sobrevivir por largos períodos de tiempo. Mostramos que la estrategia más exitosa determina la forma asintótica de la densidad metaestable cuando la tasa de infección tiende a cero, y que cuando ninguna de estas estrategias tiene éxito la infección muere rápidamente. En el segundo problema estudiamos el Proceso de Contacto sobre el lattice uno-dimensional bajo percolación dinámica con rapidez v. A diferencia del caso de percolación estática, las componentes conexas del grafo se dividen y fusionan constantemente, permitiendo a la infección moverse a través de todo el grafo, lo que le permite sobrevivir. En nuestros resultados probamos que para valores bajos de v el proceso se extingue mientras que para valores altos de este parámetro, se comporta como un Proceso de Contacto regular en Z. En el tercer problema estudiamos un modelo de poblaciones a tiempo discreto en que varias especies compiten por espacio en una red, mediante un mecanismo de propagación similar a un Proceso de Contacto multiespecie, mientras que simultáneamente son atacadas por epidemias. Nuestros resultados principales muestran que para el modelo de dos especies, existen regiones explícitas en el dominio de los parámetros dentro de los cuales podemos observar dominación o coexistencia; esto contrasta con el comportamiento del modelo sin epidemias, en las cuales la especie más apta siempre domina a las otras.
CONICYT-PCHA/Doctorado nacional/2014-21141160 y CMM Conicyt PIA AFB170001
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Sadownik, Jan. "Evolving complex systems from simple molecules." Thesis, St Andrews, 2009. http://hdl.handle.net/10023/857.
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Breckler, Matthew E. "The evolving face of ecosystem management." Connect to resource, 2006. http://hdl.handle.net/1811/6009.
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Thesis (Honors)--Ohio State University, 2006.Title from first page of PDF file. Document formattted into pages: contains 12 p.; also includes graphics. Includes bibliographical references (p. 11-12). Available online via Ohio State University's Knowledge Bank.
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Singh, Manisha G. "Labor adjustment in an evolving marketplace." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2900.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2005.Thesis research directed by: Economics. 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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Åkervik, Espen. "Feedback Control of Spatially Evolving Flows." Licentiate thesis, KTH, Mechanics, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4283.
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In this thesis we apply linear feedback control to spatially evolving flows in order to minimize disturbance growth. The dynamics is assumed to be described by the linearized Navier--Stokes equations. Actuators and sensor are designed and a Kalman filtering technique is used to reconstruct the unknown flow state from noisy measurements. This reconstructed flow state is used to determine the control feedback which is applied to the Navier--Stokes equations through properly designed actuators. Since the control and estimation gains are obtained through an optimization process, and the Navier--Stokes equations typically forms a very high-dimensional system when discretized there is an interest in reducing the complexity of the equations. One possible approach is to perform Fourier decomposition along (almost) homogeneous spatial directions and another is by constructing a reduced order model by Galerkin projection on a suitable set of vectors. The first strategy is used to control the evolution of a range of instabilities in the classical family of Falkner--Skan--Cooke flows whereas the second is applied to a more complex cavity type of geometry.
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Philippou, Anna. "Reasoning about systems with evolving structure." Thesis, University of Warwick, 1996. http://wrap.warwick.ac.uk/93676/.
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This thesis is concerned with the specification and verification of mobile systems, i.e. systems with dynamically-evolving communication topologies. The expressiveness and applicability of the πυ-calculus, an extension of the π-calculus with first-order data, is investigated for describing and reasoning about mobile systems. The theory of confluence and determinacy in the πυ-calculus is studied, with emphasis on results and techniques which facilitate process verification. The utility of the calculus for giving descriptions which are precise, natural and amenable to rigorous analysis is illustrated in three applications. First, the behaviour of a distributed protocol is analysed. The use of a mobile calculus makes it possible to capture important intuitions concerning the behaviour of the algorithm; the theory of confluence plays a central role in its correctness proof. Secondly, an analysis of concurrent operations on a dynamic search structure, the B-tree, is carried out. This exploits results obtained concerning a notion of partial confluence by whose use classes of systems in which interaction between components is of a certain disciplined kind may be analysed. Finally, the πυ-calculus is used to give a semantic definition for a concurrent-object programming language and it is shown how this definition can be used as a basis for reasoning about systems prescribed by programs. Syntactic conditions on programs are isolated and shown to guarantee determinacy. Transformation rules which increase the scope for concurrent activity within programs without changing their observable behaviour are given and their soundness proved.
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Svahnberg, Mikael. "Variability in Evolving Software Product Lines." Licentiate thesis, Karlskrona, Sweden : Kaserntryckeriet AB, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-00174.
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Software reuse is perceived as the key to successful software development because of the potential for shortened time to market, increased quality and reduced costs. In recent years software product lines have emerged as a promising way to achieve large scale software reuse. Challenges against successful reuse when developing in a software product line involves management of the differences between products, and the differences between different releases of the products. In this thesis we present the experiences from a series of case studies within four software companies. Based on these we present a taxonomy of the technical solutions to manage product differences, a historical essay of how components in a software product line can evolve and what mechanisms that are used to support this evolution. From this we elaborate on the connection between evolution and variability, i.e. the ability of the software architecture and components to support the differences between products. We argue that evolution is strongly connected to variability, and that by foreseeing the evolution, the software can be instrumented with appropriate variability mechanisms accordingly. Moreover, we argue that some types of evolution are more frequent than others, and that the efforts should mainly go in the direction of foreseeing and instrumenting for these types of evolution.
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Birek, L. "Leakage forecasting with fuzzy evolving techniques." Thesis, Coventry University, 2016. http://curve.coventry.ac.uk/open/items/33903146-10c8-45d7-9867-79ed974edb10/1.
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The amount of water lost in various leakage events in water networks in the UK not only generates economic loses for the water management companies, but more importantly, threatens supplies to households and businesses in times of severe drought.