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Stough, Joshua V. Pizer Stephen M. "Clustering and shifting of regional appearance for deformable model segmentation." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,2142.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2008.Title from electronic title page (viewed Feb. 17, 2009). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Computer Science." Discipline: Computer Science; Department/School: Computer Science.
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Trimboli, Anthony B. "An Improved Regional Honey Production Model for the United States." TopSCHOLAR®, 2017. http://digitalcommons.wku.edu/theses/1961.
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Currently three systems are used to categorize honey production regions in the United States, one from the United States Department of Agriculture, one from the American Bee Journal used for its monthly U.S. Honey Crop and Markets report, and one from Bee Culture’s monthly regional honey price report. These systems follow political state boundaries and are based upon climate, bee forage, and regional beekeeping practices. While these systems are popular with the general beekeeping community, to our knowledge, their accuracy has not been studied.
Although differing geographic regions can vary in bee forage species availability, states with similar geography and flora should have similar honey production. This is not the case because states within the same honey production region vary in honey production, possibly due to smaller ecotype divisions within the larger honey production regions. Due to this ecotype gradient, some models divide the United States into far more regions based upon ecotypes and disregard political boundaries. While a model based on ecotypes that disregard state political boundaries may be more accurate, it is not currently possible to statistically evaluate them due to how honey production data are collected.
This study developed nine novel regional honey production models that regard political boundaries while attempting to satisfy ecotype similarity. The first four alternative models are based solely on Level II ecoregions and were developed by a best fit manual approach that minimized the number of ecoregions per honey production region. The five remaining models were created using statistical k-means partitioning cluster analysis and are purely data based. Also discussed is a linear regression model produced by Page et al. Differences within and between the models were analyzed using descriptive statistics and ANOVA in order to determine an improved model that describes regional honey production in the United States.
Many of the models, both preexisting and those developed for this study, had insignificant means and are not viable. Of those that had significant means, a k-means cluster based model was determined to be the statistically superior model and can be considered an improved regional honey production model for the United States.
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Farrar, David B. "Some Model-Based and Distance-Based Clustering Methods for Characterization of Regional Ecological Stressor-Response Patterns and Regional Environmental Quality Trends." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/28824.
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We develop statistical methods for evaluation of regional variation of ecological stressor-response relationships, and regional variation in temporal profiles of water quality, for application to data from monitoring stations on bodies of water. To evaluate regional variation in regression relationships, we use model-based clustering procedures with class-specific regression models. Units for clustering are taken to be basins, or combinations of basins and ecoregions. We rely on a Bayesian formulation and sample the posterior distribution using a Markov chain Monte Carlo algorithm. Two general approaches to the label-switching problem are considered, each leading to procedures that we apply in data analyses. Two applications are presented. We explore some relationships among priors with a Dirichlet distribution for class probabilities. We compare two rank-based criteria for grouping stations according to similarities in temporal profiles. The two criteria are illustrated in a hierarchical cluster analysis based on measurements of a water quality variable.Ph. D.
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Li, Boyi. "Regional clustering through internet networks : the case of web-enabled entrepreneurial cluster in China." Thesis, London School of Economics and Political Science (University of London), 2014. http://etheses.lse.ac.uk/1041/.
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This research examines the rationale of geographic co-location of entrepreneurs who do business on internet platforms. Prior research has shown that entrepreneurs gain valuable synergy benefits from being embedded in industrial networks. Nevertheless, the advantages of geographic clustering when business is conducted via the internet are still to be understood. This research aims to understand how internet-based economic activity interacts with local social relations and structures, thus seeking to explain the phenomenon of industrial clustering of internet-enabled entrepreneurial activity. Guided by theories of relational and institutional embeddedness, we examine the way social relations are formed online, trace the rationale of local social relations while business is conducted online, and study the role of major institutional actors that support the economic activities of the entrepreneurs. Empirically, this thesis examines two regional clusters of Chinese microentrepreneurs who conduct their business on an e-commerce platform and form dynamic interpersonal ties with business partners and customers both online and offline. The method of ethnographic case study is adopted to gain in depth understanding of the ways various internet networking tools have been appropriated in business practice in these two cases and the ways local microentrepreneurs build up collaborative networks in geographic place as well as cyberspace. The study of Chinese micro-entrepreneurs reveals and substantiates the formation of a hybrid sociality, whereby economic exchange via the internet and business conducted by electronic tools are complemented by local social relations and actively supported by local government and the IT service corporation. This research also contributes to development policy considerations; it shows that regions that are usually unattractive to capital and knowledge/talent flows can gain economic development momentum by entangling the conduct of business on web platforms with local social institutions.
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Lundequist, Per. "Spatial clustering and industrial competitiveness : Studies in economic geography." Doctoral thesis, Uppsala : Department of Social and Economic Geography, Uppsala University, 2002. http://publications.uu.se/theses/99-2002-0429140456/.
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Tano, Sofia. "Migration and Regional Sorting of Skills." Doctoral thesis, Umeå universitet, Nationalekonomi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-86674.
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This thesis consists of an introductory part and four papers. Paper [I] estimates jointly the choice of whether to enroll in education and the choice of location among young people. Being a particularly mobile group, the location choices of young individuals shape much of the regional distribution of human capital, growth, and local public sector budgets. Applying Swedish register data on nest leavers, we seek to determine factors deciding the education and location choice of young people. The results indicate a systematic selection higher education based on school grades and preferences for locations with higher per capita tax bases and with lower shares of elderly people. The importance of family networks for the choice of location is confirmed. Paper [II] examines how individual ability, reflected by the grade point average (GPA) from comprehensive school affects the probability of migration among university graduates. The econometric analysis applies detailed micro-data of two entire cohorts of young individuals retrieved from the Swedish population registers. The results indicate that individual abilities are strongly influential both concerning completion of a university degree and for the migration decision. In addition, we find a positive relationship between the GPA and migrating from regions with lower per capita tax bases and/or a relatively small share of highly educated individuals. Analogously, individuals with a high GPA tend to stay in more densely populated regions, suggesting a clustering of human capital vis-à-vis school grades. Paper [III] estimates the relationship between migration across labour market regions and the subsequent changes in earnings by using the GPA from the final year of comprehensive school as a proxy for ability. This measure aims to capture heterogeneity in the returns to migration for individuals conditional on education attainment. Using Swedish register data on young adults, a difference-in-difference propensity score matching estimator is applied to estimate income differences measured up to seven years after migration. The results show variation between different ability groups regarding the returns to regional migration. There are indications of larger gains for individuals holding top grades, while the bottom half seems to benefit less, or face slightly negative effects. Paper [IV] examines whether power couple formation and the location choice of such couples are driven by factors already inherent in young people during their formative school years. The paper also extends the analysis by modeling location choice among different sizes of labor market areas, given different power statuses of the couples. Based on analysis of Swedish register data, we produce evidence that power spouses evolve from the population of high achieving school age individuals; the latter is identified by high academic performance during their years of compulsory school. Regarding location choice, the results indicate that power couples display a relatively high tendency to migrate from their regions of origin to large cities.
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Carmvall, Louise. "Regional Clustering to support Start-up businesses : - A study on social networks in Gnosjöandan and Silicon Valley -." Thesis, Växjö University, School of Management and Economics, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-6473.
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The report is aimed to stress the support of start-up businesses that exists in the environment of cluster regions. The author will introduce the reader to the conceptions of cluster regions and different shapes of social capital. The empirical study is based on two specific networks operating in two cluster areas – contributing with a broader aspect of the conception of integration. The districts are the region of Gnosjö in southern Sweden and Silicon Valley in southern San Francisco, USA. The author explore relationships between actors within the two networks and highlight two different approaches the networks use dealing with different perspectives as supporting start-up businesses. She emphasizes the importance of nurturing relations in the regional environment, with stand in natural routines and informal meetings. This will be illustrated through examples of intimate interaction in Gnosjöandan and Silicon Valley, through a perspective of regional advantage, facing global markets. The analysis is based on theoretical support with foundation in several themes of conditions for a start-up business to establish on the market. With basis in theoretical frameworks and empirical facts the report has generated an interesting argumentation of critical conditions for establishment of start-up businesses. The discussion is based on different perspectives due to the dissimilar cases used in the study. Consequently, start-up conditions, generated in cluster atmospheres, are highlighted through three interesting aspects.
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Hovander, Sebastian. "The Distance to a University and Regional Output : A Study of how Distance to a University Impacts the Economic Productivity of a Municipality." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Nationalekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-34589.
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The Swedish population is rapidly increasing in educational level in the past two decades and educational level has long been a topic of interest for labor productivity. This increase in educational level brings up an interesting discussion of whether the remoteness of a university helps create productivity and if so by how much. This is a study that will try and explain the impact on regional productivity by having a university closer, using the distance to the closest university of each municipality in Sweden, and depending on what quality this university possess. Using simple OLS regressions results have shown some reasons for increased productivity, either positive or negative, while distance showed to not matter for regional productivity at all. This field is somewhat untouched, and with further research and by including other geographical economic theories, it could become an interesting study.
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Krčál, Adam. "High-dimensional VAR analysis of regional house prices in United States." Master's thesis, Vysoká škola ekonomická v Praze, 2015. http://www.nusl.cz/ntk/nusl-202128.
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In this thesis the heterogeneity of regional real estate prices in United States is investigated. A high dimensional VAR model with additional exogenous predictors, originally introduced by \cite{fan11}, is adopted. In this framework, the common factor in regional house prices dynamics is explained by exogenous predictors and the spatial dependencies are captured by lagged house prices in other regions. For the purpose of estimation and variable selection under high-dimensional setting the concept of Penalized Least Squares (PLS) with different penalty functions (e.g. LASSO penalty) is studied in detail and implemented. Moreover, clustering methods are employed to identify subsets of statistical regions with similar house prices dynamics. It is demonstrated that these clusters are well geographically defined and contribute to a better interpretation of the VAR model. Next, we make use of the LASSO variable selection property in order to construct the impulse response functions and to simulate the prices behavior when a shock occurs. And last but not least, one-period-ahead forecasts from VAR model are compared to those from the Diffusion Index Factor Model by \cite{stock02}, a commonly used model for forecasts.
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Kondapalli, Swetha. "An Approach To Cluster And Benchmark Regional Emergency Medical Service Agencies." Wright State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=wright1596491788206805.
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Wu, Ka Yan, and Lantz Christofer Eriksson. "Building and managing an innovation hub : A case study of the challenges and opportunities faced by a Northern Swedish innovation hub." Thesis, Umeå universitet, Institutionen för informatik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-137355.
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The concept of innovation hubs are increasingly being adopted by different sectors as a means to accelerate innovation. Previous research on innovation hubs have focused on large-scale and trans-regional hubs on its managerial practices instead of its geographical situation. This paper studies an innovation hub in the Northern Swedish city of Skellefteå, in a region historically relying on heavy industry trying to transform into a high technology economy. The study aims to answer the research question: “what are the challenges and opportunities in building and managing an innovation hub to foster innovation in a geographically isolated region with a relatively small population?” To answer this question, interviews with stakeholders in the innovation hub has been conducted as part of a qualitative case study. The results indicate that the region’s large heavy industry companies provide a fertile ecosystem for startups in the digital industry by enabling the necessary supporting industries and infrastructure. Meanwhile, the lack of certain important elements needed in the startup process, most prominently private funding in the form of angel investors and venture capital, pose challenges to the development of the digital startup community in the region.
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Rulewski, Stenberg Louis. "High frequency rainfall data disaggregation with a random cascade model : Identifying regional differences in hyetographs in Sweden." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-434661.
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The field of urban hydrology is in need of high temporal resolution data series in order to effectively model and analyse existing and future trends in extreme precipitation. When high resolution data sets are, for any number of reasons, not available for a given location, the technique of disaggregation using a random cascade model can be applied. Previous studies have demonstrated the relevance of random cascades in the context of rainfall data disaggregation with temporal resolutions usually down to 1 hour. In this study, an attempt at disaggregation to a resolution of 1 minute was made. Using newly disaggregated rainfall data for different regions in Sweden, the possibility of clustering rain events into separate regional hyetographs was investigated. The random cascade model was calibrated using existing municipal rainfall data with a temporal resolution of 1 minute, in order to disaggregate continuous 15 minutes data series provided by the Swedish Meteorological and Hydrological Institute (SMHI). The disaggregation process was then performed in multiple stochastic realisations, in order to correct the uncertainties inherent to the random cascade model. The disaggregation results were assessed by comparing them with calibration data: two main rainfall parameters, EV and ED, were analysed by determining their behaviours and distribution. The possibility of transfering calibration parameters from one station to another was also assessed in a similar manner, again by studying EV & ED for different scenarios. Finally, hyetographs were clustered, compared and contrasted, in order to ascertain previously theorized differences between regions. This research showed the feasibility of applying a random cascade model to very high temporal resolutions in Sweden, while replicating rainfall characteristics from the calibration data quite well. The analysis of the spatial transferability of calibration parameters yielded inconclusive results, as rainfall characteristics were preserved in some cases but failed in others. Lastly, distinct regional differences in hyetographs were noted, but no clear conclusions could be drawn owing to the delimitations of this study.Inom småskalig hydrologisk modellering finns det idag ett behov av dataserier med hög tidsupplösning för att effektivt kunna modellera och analysera både aktuella och kommande trender hos extrema regnhändelser. När högupplösta dataserier är otillgängliga vid en önskad mätplats kan disaggregering med hjälp av en slumpmässig kaskadmodell tillämpas. Tidigare forskning har visat att kaskadmodeller är användbara för disaggregering av regndata med en tidsupplösning av 1 timme. I denna studie disaggregerades dataserier med syftet att uppnå en tidsupplösningav av 1 minut. För att kunna analysera eventuella skillnader mellan regioner klustrades även hyetografer med de framtagna dataserierna. Den slumpmässiga kaskadmodellen kalibrerades med befintlig kommunal data med en tidsupplösning på 1 minut, för att sedan kunna disaggregera 15 minuters data från SMHIs databaser. Disaggregeringen genomfördes i ett antal olika stokastiska realisationer för att kunna ta hänsyn till, och korrigera, de inneboende osäkerheterna i den slumpmässiga kaskadmodellen. Disaggregeringsresultaten bedömdes genom en jämförelse med kalibreringsdata: två regnegenskaper, regnvaraktighet (ED) och regnvolym (EV), analyserades för att kunna bestämma derasfördelningar och beteenden. Kalibreringsparametrarnas överförbarhet analyserades också med hjälp av ED & EV för olika scenarier. Slutligen klustrades hyetografer för att fastställa potentiella skillnader mellan regioner. Studien påvisade möjligheten att använda en slumpmässig kaskadmodell till höga tidsupplösningar i Sverige. Modellen lyckades återskapa regnegenskaper från kalibreringsdata vid disaggregeringen. Möjligheten att överföra kalibreringsparametrar från en station till en annan visade sig dock inte vara helt övertygande: regnegenskaper återskapades endast i vissa fall, men inte i samtliga. Slutligen konstaterades regionala skillnader i hyetografer, men tydliga slutsatser kunde inte dras på grund av underliggande begränsningar med studien.
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Dsouza, Jeevan. "Region-based Crossover for Clustering Problems." NSUWorks, 2012. http://nsuworks.nova.edu/gscis_etd/139.
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Data clustering, which partitions data points into clusters, has many useful applications in economics, science and engineering. Data clustering algorithms can be partitional or hierarchical. The k-means algorithm is the most widely used partitional clustering algorithm because of its simplicity and efficiency. One problem with the k-means algorithm is that the quality of partitions produced is highly dependent on the initial selection of centers. This problem has been tackled using genetic algorithms (GA) where a set of centers is encoded into an individual of a population and solutions are generated using evolutionary operators such as crossover, mutation and selection. Of the many GA methods, the region-based genetic algorithm (RBGA) has proven to be an effective technique when the centroid was used as the representative object of a cluster (ROC) and the Euclidean distance was used as the distance metric.
The RBGA uses a region-based crossover operator that exchanges subsets of centers that belong to a region of space rather than exchanging random centers. The rationale is that subsets of centers that occupy a given region of space tend to serve as building blocks. Exchanging such centers preserves and propagates high-quality partial solutions.
This research aims at assessing the RBGA with a variety of ROCs and distance metrics. The RBGA was tested along with other GA methods, on four benchmark datasets using four distance metrics, varied number of centers, and centroids and medoids as ROCs. The results obtained showed the superior performance of the RBGA across all datasets and sets of parameters, indicating that region-based crossover may prove an effective strategy across a broad range of clustering problems.
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Taniguchi, Yasutaka. "Clustering and deformations in sd-shell region." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/136875.
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Collings, Jared M. "Clustering Methods for Delineating Regions of Spatial Stationarity." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2175.pdf.
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Hilaris, Alexander E. "An empirical approach to logical clustering of software failure regions." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA279863.
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Kreiling, Laura. "Intermediaries in innovation ecosystems. Delineating practices and context of European Knowledge Transfer Organisations University technology transfer organizations: Roles adopted in response to their regional innovation system stakeholders A practice-based maturity model for holistic TTO performance management: development and initial use A European clustering study with Knowledge Transfer Office DNA." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASS025.
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Cette thèse porte sur les organisations intermédiaires de transfert de connaissance et de technologies des universités vers l'industrie, au sein des écosystèmes d'innovation. Les pratiques de gestion et le contexte régional des organisations européennes de transfert de connaissances (OTC) sont étudiés afin d'enrichir la compréhension de leurs déterminants managériaux. Une approche systémique est adoptée qui aboutit à des études empiriques à de multiples niveaux.La première porte sur l'influence du contexte régional et analyse le rôle des acteurs dans les systèmes d’innovation régionaux. Sur la base d'entretiens dans des OTC régionales françaises et de la théorie des parties prenantes, un modèle théorique sur l’ambidextrie de création de valeur est développé, sept parties prenantes régionales identifiées, ainsi que six rôles organisationnels adoptés.La deuxième étude porte sur les pratiques de gestion interne et examine leur maturité par rapport à d'autres dimensions de la performance des OTC en mobilisant les capacités dynamiques et la théorie de la contingence. Il en résulte l'élaboration et l'utilisation d'un modèle de maturité holistique fondé sur les pratiques managériales des OTC. Les données d'enquête de 17 OTC européennes montrent que la maturité est la plus élevée dans le domaine des pratiques de “traduction et combinaison” et la plus faible pour “la gestion des connaissances”.La troisième étude utilise le groupe de référence et l'analyse de benchmarking pour développer une approche de regroupement de OTC européennes basée sur des indicateurs d‘activité. Un cadre est proposé sur la base duquel des clusters européens transnationaux sont créés. Il en ressort que les variables liées à la culture interne de transfert des connaissances sont principalement à l'origine de la création de groupes, suivies de la variable ”'écosystème externe” et de celle relative au budget.En conclusion, cette recherche contribue à l'émergence de nouveaux thèmes dans la littérature sur le transfert des connaissances entre l'université et l'industrie, en particulier sur l'existence et l'influence des intervenants régionaux, le rôle des capacités et des pratiques dans la performance des OTC et la capacité non seulement de créer des groupes transnationaux pour le benchmarking et le benchlearning, mais aussi la mise en évidence des variables qui déterminent la création de groupes. Cela a des répercussions managériales ainsi que sur les politiques publiques, mais également offre un terrain fertile pour la recherche future en management sur les liens entre les universités et l'industrieThis thesis research is on intermediary organisations for the transfer of knowledge and technology from academia to industry in innovation ecosystems. Managerial practices and regional context of European Knowledge Transfer Organisations (KTOs) are investigated to enrich the understanding of their managerial determinants. A systemic approach is adopted resulting in research on multiple analytical levels. Consequently, the empirical part of this thesis consists of three studies.The first is on the regional context and analyses the influence of actors in the regional innovation system. Based on interviews at French regional KTOs and stakeholder theory, a theoretical model on their value creation ambidexterity is created and seven regional stakeholders identified, as well as six organisational roles which are adopted in response.The second study is on the internal managerial practices and investigates their maturity in relation to other KTO performance dimensions using dynamic capabilities and contingency theory. It results in the development and initial use of a holistic practice-based maturity model for KTO performance management. Initial data from 17 European KTOs shows that maturity is highest in the area of ‘translation & combination’ practices and lowest for ‘knowledge management’.The third study uses reference group and benchmarking theory to develop a clustering approach for the comparison of similar European KTOs based on existing activity metrics. A framework is proposed based on which transnational European peer groups are created with a clustering approach. Variables related to the internal knowledge transfer culture primarily drove cluster creation, followed by the external ecosystem and KTO budget.In conclusion, the research findings shed light on emerging topics in the university-industry knowledge transfer literature, particularly on the existence and influence of regional stakeholders, the role of capabilities and practices in performance management and the ability to not only create transnational groups for benchmarking and bench-learning but also visibility on the variables that drive cluster creation. This has managerial and policy implications as well as provides fertile ground for future research on management at the intersection of academia and industry
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Varas, González David. "Region-based particle filter leveraged with a hierarchical co-clustering." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/404443.
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In this thesis, we exploit the hierarchical information associated with images to tackle two fundamental problems of computer vision: video object segmentation and video segmentation.
In the first part of the thesis, we present a video object segmentation approach that extends the well knonw particle filter algorithm to a region-based image representation. Image partition is considered part of the particle filter measurement, which enriches the available information and leads to a reformulation of the particle filter theory. We define particles as unions of regions in the current image partition and their propagation is computed through a single optimization process. During this propoagation, the prediction step is performed using a co-clustering between the previous image object partition and a partition of the current one, which allows us to tackle the evolution of non-rigid structures.
The second part of the thesis is devoted to the exploration of a co-clustering technique for video segmentation. This technique, given a collection of images and their associated hierarchies, clusters nodes from these hierarchies to obtain a coherent multiresolution representation of the image collection. We formalize the co-clustering as a Quadratic Semi-Assignment Problem
and solve it with a linear programming relaxation approach that makes effective use of information from hierarchies. Initially, we address the problem of generating an optimal, coherent partition per image and, afterwards, we extend this method to a multiresolution framework. Finally, we particularize this framework to an iterative multiresolution video segmentation algorithm in sequences with small variations.
Finally, in the last part of the thesis we validate the presented techniques for object and video segmentation using the proposed algorithms as tools to tackle problems in a context for which they were not initially thought.En aquesta tesi, utilitzem la informació jeràrquica associada a les imatges per explorar dos problemes fonamentals de la visió per ordinador: segmentació d'objectes en vídeos i segmentació de vídeos. A la primera part de la tesi, presentem un enfoc per a la segmentació d'objectes en vídeos que estén l'algoritme de filtres de partícules a una representació basada en regions de la imatge. La partició de la imatge es considera part de la mesura del filtre de partícules, enriquint la informació disponible i permetent una reformulació de la teoria dels filtres de partícules. Definim les partícules com a unions de regions de la partició i la propagació es calcula utilitzant únicament un procés d'optimització. En aquesta propagació, la etapa de predicció es realitza mitjançant un co-clustering entres la partició de l'objecte a l'instant de temps anterior i la partició actual, permetent el seguiment d'estructures no rígides. La segona part de la tesi està dedicada al desenvolupament d'una tècnica de co-clustering per segmentació de vídeo. Donada una col·lecció d'imatges i les seves jerarquies associades, aquesta tècnica agrupa nodes de les jerarquies per obtenir una representació de la col·lecció d'imatges coherent en diferents resolucions. Formalitzem el co-clustering com un problema d'optimització linial i el resolem utilitzant unes restriccions que permeten utilitzar de manera efectiva la informació de les jerarquies. Inicialment, afrontem el problema generant una partició òptima coherent per imatge per, posteriorment, estendre aquest mètode a un context de multi-resolució. Finalment, particularitzem aquesta tècnica com a algoritme iteratiu de segmentació de vídeo a diferents resolucions en seqüències amb poc moviment. Finalment, a la darrera part de la tesi, validem les tècniques presentades per segmentació d'objectes en vídeo i segmentació de vídeo utilitzant els algoritmes proposats com a eines per resoldre problemes pels quals no havien estat pensats inicialment.
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Anz, Michael. "Entstehung von Clustern unter Berücksichtigung der Effekte regionalisierter Innovationspolitik." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-33395.
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Während man sich bislang auf die Gründe für die Entwicklung existierender Cluster konzentrierte, steigt das Interesse an den Prozessen, welche deren Entstehung bewirken. Diese unterscheiden sich jedoch von jenen zusammenhängen, welche ein reifes und dynamisches Cluster kennzeichnen (Bresnahan, Gambardella 2004, S. 842; Henn 2006b). Einige Beispiele haben gezeigt, dass Politik durchaus eine Rolle in der Entwicklung von Clustern spielen kann (z. B. Feldmann et al. 2005, S. 131; Dohse 2000b). Es herrscht jedoch Konsens, dass eine direkte Steuerung und Initiierung von Clustern „wishful thinking“ bleiben muss (Enright 2003, S. 104; Rosenfeld et al. 2006). Indes zeigen sich unternehmerische Akteure im Umfeld von Forschungseinrichtungen bevorteilt, wissenschaftliche Erkenntnisse in neuen Technologiefeldern zu verwerten. In jüngerer Zeit werden deshalb regionalisierte Innovationspolitiken implementiert, welche diesen Prozess unterstützen sollen. Über die Wirkungsweise und die Effekte einer solchen räumlich fokussierten Politik herrscht bislang jedoch noch Unklarheit (Raines 2002b, S. 8; Fromhold-Eisebith, Eisebith 2005, S. 1251; Kiese 03.10.2007). Diese Fragestellungen aufgreifend werden in der vorliegenden Arbeit anhand der Fallbeispiele Dresden und Leipzig die Prozesse der Clusterentstehung im Technologiebereich der Biotechnologie vor dem Hintergrund der Post-Transformationsphase Ostdeutschlands analysiert. Zudem wird die umfangreiche, regionalisierte Innovationspolitik des Freistaates Sachsen hinsichtlich ihres Beitrages bei der Clusterentstehung untersucht. Mit diesem Untersuchungsansatz wird ein Beitrag zur noch jungen Diskussion der Clusterentstehung geleistet sowie Einblick in die Wirkungsmöglichkeiten regionalisierter Innovationspolitik gegeben. Auf der Grundlage der theoretischen Diskussion zu Clustern und regionalisierter Innovationspolitik wird ein Untersuchungsmodell abgeleitet, welches sich an den multidimensionalen Analyserahmen Bathelts anlehnt (Bathelt 2002) und um die von Henn diskutierten Entstehungsdimensionen Ansiedlung, Lernen und Gründung erweitert (Henn 2006b). Schwerpunkt der empirischen Analyse ist ein Mix aus leitfadengestützten Interviews und quantitativer Analyse sozialer Netzwerke. Bei der Analyse zeigt sich, dass „klassische“ Erklärungsmuster zur Clusterentstehung teilweise auf Prozesse hinweisen, die sich so nicht feststellen lassen. Als wesentlich erweisen sich vor allem Gründungs- und Ansiedlungsprozesse. Zu ihrer Erklärung kann jedoch kaum auf einfache Standortfaktoren zurückgegriffen werden, vielmehr müssen Forschernetzwerke zur Erklärung herangezogen werden. Bei der Analyse der Effekte der regionalisierten Innovationspolitik zeigt sich, dass die Wirksamkeit maßgeblich von der Gestaltbarkeit und Anpassung der Politik an sich ändernde Governancebedingungen abhängt. Dies betrifft sowohl das regionale technologische Umfeld als auch die Region im Allgemeinen. Daneben 243 ist die Unterstützung der Erzeugung materieller Vorraussetzungen u. a. für den Erfolg von Ausgründungen, Ansiedlungen sowie von unternehmerischen Lernprozessen relevant. Diese müssen jedoch in flexible Strukturen eingebettet werden, die es zu entwickeln gilt. Dafür werden am Ende der Arbeit Handlungsempfehlungen aufgezeigtWhile focussing on the development of existing clusters there is a growing interest in those processes which lead to the emergence of clusters. Those differ from these ones which are typical for a ripe cluster (Bresnahan, Gambardella 2004, p. 842; Henn 2006). Several cases show that policy has an impact on the development of a cluster (z.B. Feldmann et al. 2005, p. 131; Dohse 2000). Though there is a consensus that wishing to stear or initiate a cluster is „wishful thinking“ (Enright 2003, p. 104; Rosenfeld et al. 2006). Entrepreneurs in the surrounding of research institutions are in an advantage commercialising knowledge in new technology fields. This is why regionalised innovation policies are implemented recently, which aim to support this process. The effects and mechanisms of such a spatially focused policy have yet to be clarified (Raines 2002, p. 8; Fromhold-Eisebith, Eisebith 2005, p. 1251; Kiese 3. Oktober 2007). Taking up this question in this thesis the process of emerging clusers is analysed in the field of biotechnology for the cases of Dresden and Leipzig under conditions of post-transformation in Eastern Germany. Further the influence of the complex, regionalised innovation policy of the Free State of Saxony is studied concerning the emgergence of clusters. The aim is to contribute to the discussion on emerging clusters as well as to point out the impact regionalised innovation policy can have. A research model is deduced from theoretical discussion on clusters and regionalised innovation policy. It refers to the multidimensional model of Bathelt (Bathelt 2002) and the relevant dimensions for the emergence process, settlements, learning and founding (Henn 2006). To implement this model among others a mix of semi-structured interviews and social network analysis is used. The analysis shows that “classical” explanations for emerging clusters can not be verified. Founding and settling processes of enterprises seem to be most important. A simple location factor based explanation does not give satisfying answers. Explanations have to take researcher-entrepreneurial networks into account. The analysis shows that the impact of regionalised innovation policy depends on a continual development and evolution of policy in accordance with a changing governance structure in the regional technological surrounding as in the overall region. Monetary support proves to be favourably for spin offs and settlements as well as for entrepreneurial learning processes. Those have to be embedded in flexible and developing governance structures
20
Konda, Jayashree. "Identification of protein coding regions in microbial genomes using unsupervised clustering." abstract and full text PDF (UNR users only), 2009. 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:1472961.
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Islam, A. B. M. Rezbaul. "Skin Detection in Image and Video Founded in Clustering and Region Growing." Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1538658/.
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Researchers have been involved for decades in search of an efficient skin detection method. Yet current methods have not overcome the major limitations. To overcome these limitations, in this dissertation, a clustering and region growing based skin detection method is proposed. These methods together with a significant insight result in a more effective algorithm. The insight concerns a capability to define dynamically the number of clusters in a collection of pixels organized as an image. In clustering for most problem domains, the number of clusters is fixed a priori and does not perform effectively over a wide variety of data contents. Therefore, in this dissertation, a skin detection method has been proposed using the above findings and validated. This method assigns the number of clusters based on image properties and ultimately allows freedom from manual thresholding or other manual operations. The dynamic determination of clustering outcomes allows for greater automation of skin detection when dealing with uncertain real-world conditions.
22
Leung, Kam Shek Simon. "Image processing by region extraction using a clustering approach based on colour." Thesis, University of Stirling, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281109.
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Halder, Gerhard. "Strukturwandel in Clustern am Beispiel der Medizintechnik in Tuttlingen /." Berlin [u.a.] : Lit, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=014938257&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Griffith, Alexander. "Non Parametric Unsupervised Clustering of ChIP Enrichment Regions Provides Isolation Vectors for Differential Functional Analysis." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35084.
Full textAbstract:
Gene transcription rates are influenced by proteins, known as Transcription Factors (TFs), that interact with DNA. The locations of TFs on the genome directly influence gene expression and the functional characteristics of a cell. TF binding locations can be estimated for entire genomes using high throughput chromatin immunoprecipitation sequencing (ChIP-Seq). While the analysis of ChIP-Seq binding locations is standardized for a single experiment, complications arise when data sets, taken from different labs and experimental conditions, are combined. In this thesis, I present my method for the simultaneous comparison of multiple ChIP-Seq data sets. My method of comparing multiple ChIP-Seq data sets extends the analysis of a single data set through the addition of two stages, a combination stage, and an extraction stage. Typically, one of two approaches are used to combine information from multiple datasets. Either estimated binding sites are extracted from each dataset and then combined (e.g. by various intersections or unions) or the "raw" genomic signals are analyzed by clustering or dimensionality reduction methods. Both approaches have strengths, but also substantial drawbacks. The method presented here relies both on estimating the binding sites and comparing the “raw” genomic signals between data sets. Once the binding locations have been found, the first step in the combination stage is to define an alternate feature space (AFS). The AFS is the union of all binding locations determined for all data sets. The AFS represents a subset of the genome that is likely to have TF binding in any condition where the protein is active. Once the AFS is defined, the read density is determined from the “raw” genomic signal of each of the data sets. The density is determined for all locations in the AFS resulting in a unified density matrix (UDM). The UDM is the final product of the combination stage of the analysis. After the data sets are homogenized into the UDM, the extraction stage is applied to the matrix. The extraction stage consists of applying machine learning techniques and other methods used to analyze the “raw” genomic signal, to help elucidate underlying similarities and differences between the data sets. I applied this method to the binding locations of the TF TAL1 across 22 ChIP-Seq data sets from the hematopoietic and endothelial lineages. Once the UDM had been generated and normalized, using quantile normalization, hierarchical clustering and principle component analysis (PCA) were applied. Clusters, formed by hematopoietic stem cells (HSCs), Erythroid, and T-cell acute lymphoblastic leukemia (T-ALL), were found using hierarchical clustering. The principle components (PCs) of the UDM provided weights for each peak. Using those weights I could separate groups of cellular conditions including T-ALL, Erythroid, HSC, and Endothelial Colony Forming Cells (ECFCs.) The weights also provided a quantitative measure of importance for each peak in the AFS based on how much weight they provided towards the group of interest. Functional analysis techniques, including de novo motif search and Gene Ontology, were applied to the peak partitions defined using the PCs. Motifs that were enriched in the T-ALL TAL1 partition, and not the Erythroid, were annotated and found to be similar to those that had previously been published, including Runx1 motif and a preference for the CC Ebox (CACCTG). In addition to finding the CC Ebox in T-ALL, I also show that it does not form a composite motif with GATA, indicating an alternative mechanism for the binding of TAL1 in T-ALL. This thesis establishes that heterogeneous collections of ChIP-Seq datasets, from multiple labs and experimental conditions, can be meaningfully combined, and provides an algorithmic template for doing so.
25
Christ, Julian Phillip [Verfasser]. "Innovative Places in Europe : Research Clustering, Co-Patenting Networks and the Growth of Regions / Julian Phillip Christ." Frankfurt : Peter Lang GmbH, Internationaler Verlag der Wissenschaften, 2012. http://d-nb.info/1042424837/34.
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Christ, Julian P. [Verfasser]. "Innovative Places in Europe : Research Clustering, Co-Patenting Networks and the Growth of Regions / Julian Phillip Christ." Frankfurt : Peter Lang GmbH, Internationaler Verlag der Wissenschaften, 2012. http://nbn-resolving.de/urn:nbn:de:101:1-2013093023002.
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Ersoy, Ozan. "Image Segmentation With Improved Region Modeling." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605627/index.pdf.
Full textAbstract:
Image segmentation is an important research area in digital image processing with several applications in vision-guided autonomous robotics, product quality inspection, medical diagnosis, the analysis of remotely sensed images, etc. The aim of image segmentation can be defined as partitioning an image into homogeneous regions in terms of the features of pixels extracted from the image.
Image segmentation methods can be classified into four main categories: 1) clustering methods, 2) region-based methods, 3) hybrid methods, and 4) bayesian methods. In this thesis, major image segmentation methods belonging to first three categories are examined and tested on typical images. Moreover, improvements are also proposed to well-known Recursive Shortest-Spanning Tree (RSST) algorithm. The improvements aim to better model each region during merging stage. Namely, grayscale histogram, joint histogram and homogeneous texture are used for better region modeling.
28
KC, Rabi. "Study of Some Biologically Relevant Dynamical System Models: (In)stability Regions of Cyclic Solutions in Cell Cycle Population Structure Model Under Negative Feedback and Random Connectivities in Multitype Neuronal Network Models." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou16049254273607.
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Raschke, Falk Werner. "Regionale Wettbewerbsvorteile : Identifikation, Analyse und Management von Clustern am Beispiel der Logistik im Rhein-Main-Gebiet /." Wiesbaden : Gabler, 2009. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=017626076&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Raschke, Falk Werner. "Regionale Wettbewerbsvorteile Identifikation, Analyse und Management von Clustern am Beispiel der Logistik im Rhein-Main-Gebiet." Wiesbaden Gabler, 2008. http://d-nb.info/993522378/04.
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Akteke, Basak. "Derivative Free Optimization Methods: Application In Stirrer Configuration And Data Clustering." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/2/12606591/index.pdf.
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Recent developments show that derivative free methods are highly demanded by researches for solving optimization problems in various practical contexts.
Although well-known optimization methods that employ derivative information can be very effcient, a derivative free method will be more effcient in cases
where the objective function is nondifferentiable, the derivative information is
not available or is not reliable. Derivative Free Optimization (DFO) is developed
for solving small dimensional problems (less than 100 variables) in which
the computation of an objective function is relatively expensive and the derivatives
of the objective function are not available. Problems of this nature more
and more arise in modern physical, chemical and econometric measurements
and in engineering applications, where computer simulation is employed for the
evaluation of the objective functions.
In this thesis, we give an example of the implementation of DFO in an approach
for optimizing stirrer configurations, including a parametrized grid generator,
a flow solver, and DFO. A derivative free method, i.e., DFO is preferred because
the gradient of the objective function with respect to the stirrer&rsquos design variables is not directly available. This nonlinear objective function is obtained from the flow field by the flow solver. We present and interpret numerical results of this implementation. Moreover, a contribution is given to a survey and a distinction of DFO research directions, to an analysis and discussion of these. We also state a derivative free algorithm used within a clustering algorithm in combination with non-smooth optimization techniques to reveal the effectiveness of derivative free methods in computations. This algorithm is applied on some data sets from various sources of public life and medicine. We compare various methods, their practical backgrounds, and conclude with a summary and outlook. This work may serve as a preparation of possible future research.
32
Chai, Sin-Kuo. "Multiclassifier neural networks for handwritten character recognition." Ohio : Ohio University, 1995. http://www.ohiolink.edu/etd/view.cgi?ohiou1174331633.
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Kamali-Moghaddam, Masood. "Co-operative recombination mechanisms promoting gene clustering and lateral transfer of antibacterial drug resistance." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2001. http://publications.uu.se/theses/91-554-4936-0/.
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Schricke, Esther. "Lokalisierungsmuster und Entwicklungsdynamik von Clustern der Optischen Technologien in Deutschland : untersucht am Beispiel von Clusterstrukturen in Thüringen, Bayern und Niedersachsen /." Berlin : wvb, Wiss. Verl, 2007. http://www.wvberlin.de/data/inhalt/schricke.html.
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Grimm, Alexander. "Innovation in Clustern - Cluster durch Innovation? : HipHop und Hamburger Schule ; Innovation und Clusterrevolution in der Popmusikwirtschaft am Beispiel Hamburgs /." Jena : Selbstverl. Friedrich-Schiller-Univ, 2005. http://www.gbv.de/dms/zbw/514148918.pdf.
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Fernández, Ana Belén Martin. "Tourism and economic development : retaining competitive advantage through clustering, learning and innovation in the Costa del Sol." Thesis, University of Bedfordshire, 2002. http://hdl.handle.net/10547/560723.
Full textAbstract:
This research investigates the role of clustering, learning and innovation in retaining competitiveness in an existing tourism area in a peripheral region of Europe. To do this it draws on the tourism resort area known as the Costa del Sol in southern Spain. Structurally, it focuses on hotel and catering businesses, which are considered to be at the heart of the tourism industry. Tourism is shown not only to be fundamental to the development ofthis coastal agglomeration, but also critical to the development of the province of Malaga (of which the Costa del Sol is a part) and the wider region of Andalucia. Hence the need to examine the evolution oftourism, the sources of competitive advantage and how such advantage can be retained in a globalised marketplace. The key proposition is that retaining competitive advantage can best be achieved through learning and innovation and that agglomerations provide a milieu in which learning and innovation are stimulated. Agglomeration theory and the role of learning and innovation are tested through an examination of the spatial and temporal evolution of hotel and catering businesses and through questionnaire surveys covering these businesses. In particular, the surveys are directed at addressing the issues of learning and innovation and assessing the extent to which the Costa del Sol operates as a 'learning region'. Questionnaire work met with severe problems of non-response despite being undertaken in conjunction with local business organisations. Nevertheless, sufficient responses were obtained to provide some tentative answers to the questions being posed and to provide the foundation for further research. The principal conclusions were that the Costa del Sol has acted as a growth pole and seedbed for business development, and that learning and innovation are promoted as much by competition as by co-operation. Finally, some public policy implications are drawn from these conclusions.
37
Stephens, Skylar Nicholas. "Analytical and Computational Micromechanics Analysis of the Effects of Interphase Regions, Orientation, and Clustering on the Effective Coefficient of Thermal Expansion of Carbon Nanotube-Polymer Nanocomposites." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/23216.
Full textAbstract:
Analytic and computational micromechanics techniques based on the composite cylinders method and the finite element method, respectively, have been used to determine the effective coefficient of thermal expansion (CTE) of carbon nanotube-epoxy nanocomposites containing aligned nanotubes. Both techniques have been used in a parametric study of the influence of interphase stiffness and interphase CTE on the effective CTE of the nanocomposites. For both the axial and transverse CTE of aligned nanotube nanocomposites with and without interphase regions, the computational and analytic micromechanics techniques were shown to give similar results. The Mori-Tanka method has been used to account for the effect of randomly oriented fibers. Analytic and computational micromechanics techniques have also been used to assess the effects of clustering and clustering with interphase on the effective CTE components. Clustering is observed to have a minimal impact on the effective axial CTE of the nanocomposite and a 3-10%. However, there is a combined effect with clustering and one of the interphase layers.Master of Science
38
Tadepally, Harika. "Spatiotemporal Variation of Continuous PM2.5 In Cincinnati: Analyzing The Impacts of Local-Scale Emissions Versus Meteorological Variability." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1504802386325803.
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Wimberly, Brent. "Identification of spatiotemporal nutrient patterns and associated ecohydrological trends in the tampa bay coastal region." Honors in the Major Thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/642.
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Improvements for environmental monitoring and assessment were achieved to advance our understanding of sea-land interactions and nutrient cycling in a coastal bay.; The comprehensive assessment techniques for monitoring of water quality of a coastal bay can be diversified via an extensive investigation of the spatiotemporal nutrient patterns and the associated eco-hydrological trends in a coastal urban region. With this work, it is intended to thoroughly investigate the spatiotemporal nutrient patterns and associated eco-hydrological trends via a two part inquiry of the watershed and its adjacent coastal bay. The findings show that the onset of drought lags the crest of the evapotranspiration and precipitation curve during each year of drought. During the transition year, ET and precipitation appears to start to shift back into the analogous temporal pattern as the 2005 wet year. NDVI shows a flat receding tail for the September crest in 2005 due to the hurricane impact signifying that the hurricane event in October dampening the severity of the winter dry season in which alludes to relative system memory. The k-means model with 8 clusters is the optimal choice, in which cluster 2 at Lower Tampa Bay had the minimum values of total nitrogen (TN) concentrations, chlorophyll a (Chl-a) concentrations, and ocean color values in every season as well as the minimum concentration of total phosphorus (TP) in three consecutive seasons in 2008. Cluster 5, located in Middle Tampa Bay, displayed elevated TN concentrations, ocean color values, and Chl-a concentrations, suggesting that high colored dissolved organic matter values are linked with some nutrient sources. The data presented by the gravity modeling analysis indicate that the Alafia River Basin is the major contributor of nutrients in terms of both TP and TN values in all seasons. Such ecohydrological evaluation can be applied for supporting the LULC management of climatic vulnerable regions as well as further enrich the comprehensive assessment techniques for estimating and examining the multi-temporal impacts and dynamic influence of urban land use and land cover.B.S.C.E.
Bachelors
Engineering and Computer Science
Civil Engineering
40
Keller, Thomas [Verfasser]. "Entwicklung und Gestaltung von Netzwerkaktivitäten und Kommunikationsinhalten in regionalen Netzwerken und Clustern : eine formative und summative Evaluationsstudie am Beispiel eines Umwelttechnologieclusters in Mittelhessen / Thomas Keller." Gießen : Universitätsbibliothek, 2014. http://d-nb.info/1068468769/34.
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Klöpper, Christof. "Globale Netzwerke, regionale Einflüsse: die Struktur und Geographie von Innovationsprozessen in der Biotechnologie : eine Analyse der Innovationsnetzwerke von Biotechnologieunternehmen in elf Clustern in der Schweiz, Deutschland, Frankreich und Grossbritannien /." Basel : [s.n.], 2009. http://edoc.unibas.ch/diss/DissB_8846.
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Aksoy, Ece. "An Attempt To Classify Turkish District Data: K-means And Self-organizing Map (som) Algorithms." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12605711/index.pdf.
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ABSTRACT
AN ATTEMPT TO CLASSIFY TURKISH DISTRICT DATA: K-MEANS AND SELF-ORGANIZING MAP (SOM) ALGORITHMS
Aksoy, Ece
M.S., Department of Geodetic and Geographic Information Systems
Supervisor: Assoc. Prof. Dr. Oguz ISik
December 2004, 112 pages
There is no universally applicable clustering technique in discovering the variety of structures display in data sets. Also, a single algorithm or approach is not adequate to solve every clustering problem. There are many methods available, the criteria used differ and hence different classifications may be obtained for the same data. While larger and larger amounts of data are collected and stored in databases, there is increasing the need for efficient and effective analysis methods. Grouping or classification of measurements is the key element in these data analysis procedures. There are lots of non-spatial clustering techniques in various areas. However, spatial clustering techniques and software are not so common.
This thesis is an attempt to classify Turkish district data with the help of two clustering algorithms: K-means clustering and self organizing maps (SOM). With the help of these two common techniques it is expected that a clustering can be reached, which can be used for different aims such as regional politics, constructing statistical integrity or analyzing distribution of funds, for same data in GIS environment and putting forward the facilitative usage of GIS in regional and statistical studies.
All districts of Turkey, which is 923 units, were chosen as an application area in this thesis. Some limitations such as population were specified for clustering of Turkey&rsquos districts. Firstly, different clustering techniques for spatial classification were researched. K-Means and SOM algorithms were chosen to compare different methods with Turkey&rsquo
s district data. Afterward, database of Turkey&rsquo
s statistical datum was formed and analyzed joining with geographical data in the GIS environment. Different clustering software, ArcGIS, CrimeStat and Matlab, were applied according to conclusion of clustering techniques research. Self Organizing Maps (SOM) algorithm, which is the best and most common spatial clustering algorithm in recent years, and CrimeStat K-Means clustering were used in this thesis as clustering methods.
43
Kasahara, Viviani Akemi. "Agrupamento de sequências de miRNA utilizando aprendizado não-supervisionado baseado em grafos." Universidade Federal de São Carlos, 2016. https://repositorio.ufscar.br/handle/ufscar/8124.
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Não recebi financiamento
Cluster analysis is the organization of a collection of patterns into clusters based on similarity which is determined by using properties of data. Clustering techniques can be useful in a variety of knowledge domains such as biotechnology, computer vision, document retrieval and many others. An interesting area of biology involves the concept of microRNAs (miRNAs) that are approximately 22 nucleotide-long non-coding RNA molecules that play important roles in gene regulation. Clustering miRNA sequences can help to understand and explore sequences belonging to the same cluster that has similar biological functions. This research work investigates and explores seven unsupervised clustering algorithms based on graphs that can be divided into three categories: algorithm based on region of influence, algorithm based on minimum spanning tree and spectral algorithm. To assess the contribution of the proposed algorithms, data from miRNA families stored in the online miRBase database were used in the conducted experiments. The results of these experiments were presented, analysed and evaluated using clustering validation indexes as well as visual analysis.
A análise de agrupamento é uma organização de coleção de padrões em grupos, baseando-se na similaridade das propriedades pertencentes aos dados. A técnica de agrupamento pode ser utilizado em muitas áreas de conhecimento como biotecnologia, visão computacional, recuperação de documentos, entre outras. Uma área interessante da biologia envolve o conceito de microRNAs (miRNAs), que são moléculas não-codificadas de RNA com aproximadamente 22 nucleotídeos e que desempenham um papel importante na regulação dos genes. O agrupamento de sequências de miRNA podem ajudar em sua exploração e entendimento, pois as sequências que pertencem ao mesmo grupo possuem uma função biológica similar. Esse trabalho explora e investiga sete algoritmos de agrupamentos não-supervisionados baseados em grafos que podem ser divididos em três categorias: algoritmos baseados em região de influência, algoritmos baseados em árvore spanning minimal e algoritmo espectral. Para avaliar a contribuição dos algoritmos propostos, os experimentos conduzidos utilizaram os dados das famílias de miRNAs disponíveis no banco de dados denominado miRBase. Os resultados dos experimentos foram apresentados, analisados e avaliados usando índices de validação de agrupamento e análise visual.
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Silva, Cibele de Cássia. "Estrutura filogenética e variação de caracteres funcionais em cerrados rupestres do Brasil Central." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/5847.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
In this study, we investigate the role of underling evolutionary process in current phylogenetic structure of tree and shrub assemblages from rocky savanna, which is a habitat type from Cerrado biome. Besides, we analyzed whether species that occurr in both contrasting habitats types from Cerrado biome: rocky savanna and savannas, have varying functional traits in intraspecific level in response to different environmental conditions. For this, we splitted this dissertation in two chapters. In the first chapter, we aimed to understand the role of historical and evolutionary contingencies, diversification patterns and different clades distributions in shaping the current diversity of trees and shrubs from rocky savannas. Furthermore, we also seeked understanding the role of scale and species pool in phylogenetic structure of tree and shrub assemblages from rocky savanna. In the second chapter, again using trees and shrubs as study model, we investigated the occurrence of different ecological strategies in individuals of the same species, according to the type of habitats in which they occurred. Specifically, we addressed the variation of functional traits in species occurring both in rocky savannas such as in geographically adjacent savannas.
Neste trabalho, procuramos entender a influência de processos evolutivos subjacentes na estrutura filogenética de assembleias de árvores e arbustos de um tipo de habitat do Cerrado: o cerrado rupestre. Além disto, avaliamos se espécies que ocorrem tanto em cerrado rupestre quanto em cerrado sensu stricto apresentam variação de atributos funcionais em nível intraespecífico em resposta as diferentes condições ambientais. Para isso, dividimos esta dissertação em dois capítulos. No primeiro capítulo, buscamos compreender o papel das contingências histórico-evolutivas, padrões de diversificação e distribuição de diferentes clados na formação da diversidade atual do componente arbustivo-arbóreo do cerrado rupestre. Além disto, buscamos compreender também a influência da escala e do pool de espécies na estrutura filogenética de assembleias de arvores e arbustos do cerrado rupestre. No segundo capítulo, novamente utilizando o componente arbustivo-arbóreo como modelo de estudo, nós investigamos a ocorrência estratégias ecológicas distintas em indivíduos de uma mesma espécie, de acordo com o tipo de habitat em que estavam inseridos. Especificamente, avaliamos a variação de atributos funcionais em espécies que ocorriam tanto em cerrado rupestre quanto em cerrado sensu stricto adjacente.
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Grahn, Fredrik, and Kristian Nilsson. "Object Detection in Domain Specific Stereo-Analysed Satellite Images." Thesis, Linköpings universitet, Datorseende, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-159917.
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Given satellite images with accompanying pixel classifications and elevation data, we propose different solutions to object detection. The first method uses hierarchical clustering for segmentation and then employs different methods of classification. One of these classification methods used domain knowledge to classify objects while the other used Support Vector Machines. Additionally, a combination of three Support Vector Machines were used in a hierarchical structure which out-performed the regular Support Vector Machine method in most of the evaluation metrics. The second approach is more conventional with different types of Convolutional Neural Networks. A segmentation network was used as well as a few detection networks and different fusions between these. The Convolutional Neural Network approach proved to be the better of the two in terms of precision and recall but the clustering approach was not far behind. This work was done using a relatively small amount of data which potentially could have impacted the results of the Machine Learning models in a negative way.
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Brunner, Manuela. "Hydrogrammes synthétiques par bassin et types d'événements. Estimation, caractérisation, régionalisation et incertitude." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAU003/document.
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L'estimation de crues de projet est requise pour le dimensionnement de barrages et de bassins de rétention, de même que pour la gestion des inondations lors de l’élaboration de cartes d’aléas ou lors de la modélisation et délimitation de plaines d’inondation. Généralement, les crues de projet sont définies par leur débit de pointe à partir d’une analyse fréquentielle univariée. Cependant, lorsque le dimensionnement d’ouvrages hydrauliques ou la gestion de crues nécessitent un stockage du volume ruisselé, il est également nécessaire de connaître les caractéristiques volume, durée et forme de l’hydrogramme de crue en plus de son débit maximum. Une analyse fréquentielle bivariée permet une estimation conjointe du débit de pointe et du volume de l’hydrogramme en tenant compte de leur corrélation. Bien qu’une telle approche permette la détermination du couple débit/volume de crue, il manque l’information relative à la forme de l’hydrogramme de crue. Une approche attrayante pour caractériser la forme de la crue de projet est de définir un hydrogramme représentatif normalisé par une densité de probabilité. La combinaison d’une densité de probabilité et des quantiles bivariés débit/volume permet la construction d’un hydrogramme synthétique de crue pour une période de retour donnée, qui modélise le pic d’une crue ainsi que sa forme. De tels hydrogrammes synthétiques sont potentiellement utiles et simples d’utilisation pour la détermination de crues de projet. Cependant, ils possèdent actuellement plusieurs limitations. Premièrement, ils reposent sur la définition d’une période de retour bivariée qui n’est pas univoque. Deuxièmement, ils décrivent en général le comportement spécifique d’un bassin versant en ne tenant pas compte de la variabilité des processus représentée par différents types de crues. Troisièmement, les hydrogrammes synthétiques ne sont pas disponibles pour les bassins versant non jaugés et une estimation de leurs incertitudes n’est pas calculée.Pour remédier à ces manquements, cette thèse propose des avenues pour la construction d’hydrogrammes synthétiques de projet pour les bassins versants jaugés et non jaugés, de même que pour la prise en compte de la diversité des types de crue. Des méthodes sont également développées pour la construction d’hydrogrammes synthétiques de crue spécifiques au bassin et aux événements ainsi que pour la régionalisation des hydrogrammes. Une estimation des diverses sources d’incertitude est également proposée. Ces travaux de recherche montrent que les hydrogrammes synthétiques de projet constituent une approche qui s’adapte bien à la représentation de différents types de crue ou d’événements dans un contexte de détermination de crues de projet. Une comparaison de différentes méthodes de régionalisation montre que les hydrogrammes synthétiques de projet spécifiques au bassin peuvent être régionalisés à des bassins non jaugés à l’aide de méthodes de régression linéaires et non linéaires. Il est également montré que les hydrogrammes de projet spécifiques aux événements peuvent être régionalisés à l’aide d’une approche d’indice de crue bivariée. Dans ce contexte, une représentation fonctionnelle de la forme des hydrogrammes constitue un moyen judicieux pour la délimitation de régions ayant un comportement hydrologique de crue similaire en terme de réactivité. Une analyse de l’incertitude a montré que la longueur de la série de mesures et le choix de la stratégie d’échantillonnage constituent les principales sources d’incertitude dans la construction d’hydrogrammes synthétiques de projet. Cette thèse démontre qu’une approche de crues de projet basée sur un ensemble de crues permet la prise en compte des différents types de crue et de divers processus. Ces travaux permettent de passer de l’analyse fréquentielle statistique de crues vers l’analyse fréquentielle hydrologique de crues permettant de prendre en compte les processus et conduisant à une prise de décision plus éclairéeDesign flood estimates are needed in hydraulic design for the construction of dams and retention basins and in flood management for drawing hazard maps or modeling inundation areas. Traditionally, such design floods have been expressed in terms of peak discharge estimated in a univariate flood frequency analysis. However, design or flood management tasks involving storage, in addition to peak discharge, also require information on hydrograph volume, duration, and shape . A bivariate flood frequency analysis allows the joint estimation of peak discharge and hydrograph volume and the consideration of their dependence. While such bivariate design quantiles describe the magnitude of a design flood, they lack information on its shape. An attractive way of modeling the whole shape of a design flood is to express a representative normalized hydrograph shape as a probability density function. The combination of such a probability density function with bivariate design quantiles allows the construction of a synthetic design hydrograph for a certain return period which describes the magnitude of a flood along with its shape. Such synthetic design hydrographs have the potential to be a useful and simple tool in design flood estimation. However, they currently have some limitations. First, they rely on the definition of a bivariate return period which is not uniquely defined. Second, they usually describe the specific behavior of a catchment and do not express process variability represented by different flood types. Third, they are neither available for ungauged catchments nor are they usually provided together with an uncertainty estimate.This thesis therefore explores possibilities for the construction of synthetic design hydrographs in gauged and ungauged catchments and ways of representing process variability in design flood construction. It proposes tools for both catchment- and flood-type specific design hydrograph construction and regionalization and for the assessment of their uncertainty.The thesis shows that synthetic design hydrographs are a flexible tool allowing for the consideration of different flood or event types in design flood estimation. A comparison of different regionalization methods, including spatial, similarity, and proximity based approaches, showed that catchment-specific design hydrographs can be best regionalized to ungauged catchments using linear and nonlinear regression methods. It was further shown that event-type specific design hydrograph sets can be regionalized using a bivariate index flood approach. In such a setting, a functional representation of hydrograph shapes was found to be a useful tool for the delineation of regions with similar flood reactivities.An uncertainty assessment showed that the record length and the choice of the sampling strategy are major uncertainty sources in the construction of synthetic design hydrographs and that this uncertainty propagates through the regionalization process.This thesis highlights that an ensemble-based design flood approach allows for the consideration of different flood types and runoff processes. This is a step from flood frequency statistics to flood frequency hydrology which allows better-informed decision making
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NGUYEN, BICH-PHUONG, and 阮碧鳳. "Regional Economic Growth And Small And Medium Enterprises Clustering." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/s7832y.
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碩士國立臺北大學
城市治理英語碩士學位學程
107
The research hypothesis is on whether the agglomeration of small and medium enterprises (SMEs) is capable of boosting the economic growth of a region has intrigued many spatial economists and economic geographers. This paper uses cross-sectional data over 357 townships in Taiwan in 2001 and 2011 with two main instruments employed are the Exploration Spatial Data Analysis and Spatial Regression. Initial outcomes show remarkable influences of spatial autocorrelation among all variables, strongest among active population growth, level of income per person and employment of SMEs with 0.001 level of significances. Thus, the null hypothesis of which claims that each observation is independent is rejected. Moreover, the nonconformity between results from the classic original least square and the spatial models also suggest that the exclusion of Spatial Econometrics from the growth model could impart a biased result. On the other hand, while some scientists found a negative relationship between SMEs development with the regional economic growth (Cravo et al. 2015, Davis et al 1996a), most of others still consider SMEs as an important factor that generate employment, competitiveness and as a source of innovation (Acs and Audretsch 1993, Qian and Acs 2013, Fritsch and Mueller 2004). The empirical result of this study does not support the pro-SMEs theories since local SMEs have a negative coefficient with local income growth while this of large enterprises is positive. Besides, the large sector also has a strong impact on neighboring income growth. Another confirmation is the lower level of income the faster the growth, which complied with the beta-convergence theory by Sala-i Martin (1996).
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Chen, Zhi-Mou, and 陳智謀. "Rainfall Stations Clustering and Regional Flood Disaster Indicator Assessment." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/84134716552354255230.
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博士國立屏東科技大學
土木工程系所
104
The natural disaster statistics shows that cyclones and heavy rain caused flooding disaster, hence threaten people’s lives. Therefore, the combination of the analysis of rainfall amount during intense rainfall events and flood disasters survey results to develop flood disaster prevention and relief measures, which is one of the best way to respond the uncertainty of disaster events. In this study we selected Pingtung County as the study area and focused on flood hazard analysis to investigate rainfall distribution and to develop flood indicator during typhoon and heavy rainfall events. For the rainfall data during flood disaster event, this study employed cluster analysis method. Firstly, we taken inverse distance weighting method to add rainfall to station having loss rainfall, then rainfall spatial distribution can be obtained during disaster events. The rainfall data was used to conduct clustering of rainfall stations. The clustering analysis taken two-step method that Ward’s clustering method was used to obtain clustering distance of rainfall stations and values of mean square standard deviation were used to decide optimal clustering group. Finally, K-Mean clustering method and GIS were used to establish clustering result. This study used multi-attributes decision method to assess flooding indicators that assessed items included area of individual flooding disaster, flooding potential analysis, reasons causing flooding, and flooding environmental characteristics. The following steps were taken for the analysis: (1) Normalization of the collected flooding data with the factors obtained in accordance with the characteristics of the various data. (2) The normalization factors were analyzed for their entropy, which determined a weighting value. (3) Various factors were integrated into the flooding disaster indicator based on their weighting values. From the cluster analysis results showed that the rainfall spatial and temporal distribution was similar in the same clustering group. If rainfall data was lost in a station due to any reason, we can carry inverse distance weighting calculation for addendum rainfall data to the station with the rainfall data in the same clustering group. In addition, the flooding disaster indicator had a positive correlation with the flooding area of past flooding disaster events and flooding disaster potential. The ranking of established indicator can distinguish the extent of flood hazards.
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Chiang, Tung-Hung, and 江東鴻. "Study on Regional Energy Aware Clustering with Isolated Nodes in Wireless Sensor Networks." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/26427204069623529684.
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碩士國立臺灣科技大學
電子工程系
102
Energy consumption is a critical concern in the design of wireless sensor networks (WSNs), which are typically powered by limited energy resources. A suitable clustering algorithm for grouping sensor nodes can increase the energy efficiency of WSNs. However, clustering requires additional overhead, such as cluster head (CH) selection and assignment and cluster construction. This paper proposes a new regional energy aware clustering method using isolated nodes for WSNs, called Regional Energy Aware Clustering with Isolated Nodes (REAC-IN). In REAC-IN, CHs are selected based on weight. Weight is determined according to the residual energy of each sensor and the regional average energy of all sensors in each cluster. Improperly designed distributed clustering algorithms can cause nodes to become isolated from CHs. Such isolated nodes communicate with the sink by consuming an excess amount of energy. To reduce energy consumption and prolong network lifetime, the regional average energy and the distance between sensors and the sink are used to determine whether the isolated node sent its data to a CH node in the previous round or to the sink. The simulation results of the current study revealed that REAC-IN outperforms other clustering algorithms, namely the LEACH, HEED, and DEEC algorithms, in the total number of transferred data, total network energy consumption, and network lifetime.
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Wang, Wu-Han, and 王梧翰. "Exploring the Effective Evaluation Indices of Self-Organizing Map for Clustering Regional Flood Inundation Map." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/sdu4s7.
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碩士淡江大學
水資源及環境工程學系碩士班
106
Today, Artificial Intelligence is one of popular issues with many research topics and practical applications. The relative AI issues on the study of water resource management or flood forecast have become one of important topics. The purpose of this study is to propose the methodology to automatically build the Self-organizing maps (SOM) on clustering the flood spatial distribution. There are three major problems on building the SOM model; first one is the topological error, that is, any two neurons flip each other weights that makes the order of the topological map; second one is to the selection of the number of epochs. The training algorithm of SOM has two phases, ordering phase and convergent phase. Hence, these two phases have the different number of epochs and the number of epochs can influence the convergence; third one is to decide the optimal size. This study proposes two training strategies of the SOM models and takes Luermen Creek and Yenshui Creek located in Tainan, and Kemaman River located in Terengganu of Malaysia to investigate the convergence of the SOM models. The first strategy, called plan1, is to train the network in the ordering phase until the weights of the neurons have no obvious change, then transfer to the convergent phase and continue training the neurons until the weights have no obvious change. The second strategy, called plan2, is to rain the network in the ordering phase until the coverage rate of weights reaches 50%, then transfer to the convergent phase and continue training the same as the convergent phase of plan1. We use the flood simulation data of these three areas as the training data to build their own models. Through the different training strategy of plan1 and plan2, we can explore the influences of the ordering and convergent phases on building the SOM models. Through coverage rate, flip detector and five indices to compare the clustering results of the SOM clustering results. The coverage rate is defined as the difference of the cumulative distribution rates between maximum and minimum weights (neurons). The flip detector can check whether any two or more neurons flip each other weights or not and determine topological order correct or not. The clustering results of these three cases show that the number of epochs can influence the coverage rate and effectively improve the clustering quality. The larger number of epochs can get the larger coverage rate. The results show that plan2 can get convergent clustering results while plan1 occurs flip in Luermen Creek and Kemaman River. Hence plan2 is more suitable than plan1 for applying the SOM model on clustering the flood spatial distribution. Moreover, for comparison of the different size of the SOM models, the results demonstrate that the coverage rates of 3×3 model are smaller than those of 4×4 and 5×5 models, about 5%-10% less. That means 3×3 model cannot describe the characteristics of data as well as 4×4 and 5×5 models. The coverage rates of 4×4 and 5×5 models are almost the same, so the small models should be enough neurons to describe the data, that is, 4×4 is an appropriate size than other models. Hence, for choosing the size of topology map, the coverage rate is the great index to decide the optimal size.