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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
861

Mokyklos sporto būrelis kaip papildomo ugdymo forma / School sport's cluster like additional education form

Grabliauskaitė, Aušra 15 June 2005 (has links)
School sport’s cluster like additional education form In this work attention is given to one of out –off-school activities example – sport’s cluster like additional education form. Wich would nurture and reinforce not only during lesson time achived knowledge, but alsowould help to form good future citizen and human, wich has values, goals, aim. Lately big attention is given to children and youth business, lack of it and possible connection to youth criminal problems of it. By different means and ways there is desire to increase schoolchildren business, education, nurturing. Research subject: sport’s clusters education possibilities. The goal of the work is to detect attitude of Vilnius city schools teachers and pupils to schools sport’s clusters activities and educational possibilities by pedagogical and social aspect. To achieve this goal the following issues have been analyzed: out-off-school sport’s activities in Vilnius city for pupils, also realistic sport’s activity as educational method. Also analyzed influance of economic enviromental elements to schoolchildren in out-off-class activities. In the survey were 601 respondents: 365 pupils participate in sports clusters, 203 pupils not participate in sports clusters and 33 sports clusters teachers.The survey has been performed using the theoretical method – analysis of pedagogical and scientific literature, inquiry of documentation; empirical method – questionnaire survey of pupils... [to full text]
862

GRID projektavimas / GRID designing

Vladyka, Albinas 16 August 2007 (has links)
Darbo „Grid projektavimas“ tikslas – suprojektuoti, sukonfigūruoti telkinį Šiaulių universitete ir prijungti jį prie bendro Litgrid ir Balticgrid tinklyno. Pagrindiniai šio darbo uždaviniai yra orientuoti į darbo tikslą ir apima ne tik programinius sprendimus, bet ir vartotojų mokymų organizavimą bei galimybių šiam tikslui panaudoti mokymo klas÷se esančius kompiuterius analizę ir rekomendacijas. Šiame darbe įdiegta ir sukonfigūruota programin÷ įranga, telkinys prijungtas prie virtualiųjų organizacijų Litgrid ir Balticgrid, sukurti scenarijai, automatizuojantys programų diegimą ir konfigūravimą. Telkinio pristatymas, metodin÷s rekomendacijos ir mokymai darbui su juo buvo realizuoti dviejose konferencijose. Darbas inovatyvus tuo, kad tokio pobūdžio virtualus kompiuteris yra pirmasis ir vienintelis Šiaulių regione - jis sudaro sąlygas panaudoti jau turimus kompiuterius didel÷s apimties skaičiavimo resursams imlių uždavinių sprendimui. / The purpose of the project "Grid designing" is to design and to configure the cluster at Siauliai University and connect it to Litgrid and Balticgrid. The main problems of this project are orientated towards the objective of the project and include not only software solutions, but also organization of users training and analysis as well as recommendations on possibilities to employ computers located at the teaching classes for that purpose too. This project has installed and configured software, the cluster is connected to virtual organizations of Litgrid and Balticgrid, it has created scripts, which automates installation and configuration of programs. Cluster, methodological recommendations and training for it were presented in two conferences. The project is innovative because it is the first and the only virtual computer of such nature in Siauliai region, which enables to use available computers to solve tasks that require big volumes of calculating resources.
863

Mixtures of Skew-t Factor Analyzers

Murray, Paula 11 1900 (has links)
Model-based clustering allows for the identification of subgroups in a data set through the use of finite mixture models. When applied to high-dimensional microarray data, we can discover groups of genes characterized by their gene expression profiles. In this thesis, a mixture of skew-t factor analyzers is introduced for the clustering of high-dimensional data. Notably, we make use of a version of the skew-t distribution which has not previously appeared in mixture-modelling literature. Allowing a constraint on the factor loading matrix leads to two mixtures of skew-t factor analyzers models. These models are implemented using the alternating expectation-conditional maximization algorithm for parameter estimation with an Aitken's acceleration stopping criterion used to determine convergence. The Bayesian information criterion is used for model selection and the performance of each model is assessed using the adjusted Rand index. The models are applied to both real and simulated data, obtaining clustering results which are equivalent or superior to those of established clustering methods.
864

Assessing the impact of human activities on British Columbia's estuaries

Robb, Carolyn Kathleen 01 August 2013 (has links)
The world's marine and coastal ecosystems are under threat and single-sector management efforts have failed to address those threats. Scientific consensus suggests that management should evolve to focus on ecosystems and their human, ecological, and physical components. Estuaries are recognized globally as one of the world's most productive and most threatened ecosystems and many estuarine areas in British Columbia (BC) have been lost or degraded. To help prioritize activities and areas for management efforts at a regional scale, spatial information on human activities that adversely affect BC estuaries was compiled. Using statistical analyses, estuaries were assigned to groups facing related threats that could benefit from similar management. The relationships between estuaries, their biological importance, and their protected status were examined. This research is timely as it will inform ongoing marine planning efforts as well as land acquisition and stewardship activities undertaken by organizations such as the Pacific Estuary Conservation Program.
865

Automatic text summarization using lexical chains : algorithms and experiments

Kolla, Maheedhar, University of Lethbridge. Faculty of Arts and Science January 2004 (has links)
Summarization is a complex task that requires understanding of the document content to determine the importance of the text. Lexical cohesion is a method to identify connected portions of the text based on the relations between the words in the text. Lexical cohesive relations can be represented using lexical chaings. Lexical chains are sequences of semantically related words spread over the entire text. Lexical chains are used in variety of Natural Language Processing (NLP) and Information Retrieval (IR) applications. In current thesis, we propose a lexical chaining method that includes the glossary relations in the chaining process. These relations enable us to identify topically related concepts, for instance dormitory and student, and thereby enhances the identification of cohesive ties in the text. We then present methods that use the lexical chains to generate summaries by extracting sentences from the document(s). Headlines are generated by filtering the portions of the sentences extracted, which do not contribute towards the meaning of the sentence. Headlines generated can be used in real world application to skim through the document collections in a digital library. Multi-document summarization is gaining demand with the explosive growth of online news sources. It requires identification of the several themes present in the collection to attain good compression and avoid redundancy. In this thesis, we propose methods to group the portions of the texts of a document collection into meaningful clusters. clustering enable us to extract the various themes of the document collection. Sentences from clusters can then be extracted to generate a summary for the multi-document collection. Clusters can also be used to generate summaries with respect to a given query. We designed a system to compute lexical chains for the given text and use them to extract the salient portions of the document. Some specific tasks considered are: headline generation, multi-document summarization, and query-based summarization. Our experimental evaluation shows that efficient summaries can be extracted for the above tasks. / viii, 80 leaves : ill. ; 29 cm.
866

Aggregation in large scale quadratic programming

Foster, David Martin 08 1900 (has links)
No description available.
867

Optimization-Based Network Analysis with Applications in Clustering and Data Mining

Shahinpour, Shahram 16 December 2013 (has links)
In this research we develop theoretical foundations and efficient solution methods for two classes of cluster-detection problems from optimization point of view. In particular, the s-club model and the biclique model are considered due to various application areas. An analytical review of the optimization problems is followed by theoretical results and algorithmic solution methods developed in this research. The maximum s-club problem has applications in graph-based data mining and robust network design where high reachability is often considered a critical property. Massive size of real-life instances makes it necessary to devise a scalable solution method for practical purposes. Moreover, lack of heredity property in s-clubs imposes challenges in the design of optimization algorithms. Motivated by these properties, a sufficient condition for checking maximality, by inclusion, of a given s-club is proposed. The sufficient condition can be employed in the design of optimization algorithms to reduce the computational effort. A variable neighborhood search algorithm is proposed for the maximum s-club problem to facilitate the solution of large instances with reasonable computational effort. In addition, a hybrid exact algorithm has been developed for the problem. Inspired by wide usability of bipartite graphs in modeling and data mining, we consider three classes of the maximum biclique problem. Specifically, the maximum edge biclique, the maximum vertex biclique and the maximum balanced biclique problems are considered. Asymptotic lower and upper bounds on the size of these structures in uniform random graphs are developed. These bounds are insightful in understanding the evolution and growth rate of bicliques in large-scale graphs. To overcome the computational difficulty of solving large instances, a scale-reduction technique for the maximum vertex and maximum edge biclique problems, in general graphs, is proposed. The procedure shrinks the underlying network, by confirming and removing edges that cannot be in the optimal solution, thus enabling the exact solution methods to solve large-scale sparse instances to optimality. Also, a combinatorial branch-and-bound algorithm is developed that best suits to solve dense instances where scale-reduction method might be less effective. Proposed algorithms are flexible and, with small modifications, can solve the weighted versions of the problems.
868

Text Document Topical Recursive Clustering and Automatic Labeling of a Hierarchy of Document Clusters

Li, Xiaoxiao Unknown Date
No description available.
869

The thermal Sunyaev-Zel'dovich effect as a probe of cluster physics and cosmology.

Warne, Ryan Russell. January 2010 (has links)
The universe is a complex environment playing host to a plethora of macroscopic and microscopic processes. Understanding the interplay and evolution of such processes will help to shed light on the properties and evolution of the universe. The juxtaposition is that in order to study small scale effects one needs to observe large scale structure as the latter objects trace the history of our universe. Galaxy groups and clusters are the largest known objects in the universe and thus provide a means to probe the evolution of structure formation in the universe as well as the underlying cosmology. In this thesis we investigate how clusters observed through the Sunyaev-Zel’dovich (SZ) effect can be used to constrain cosmological models. In addition, we present the first results of the Atacama Cosmology Telescope (ACT), a mm-wave telescope measuring the small-scale microwave background anisotropy, and conclude with preliminary SZ cluster detection performed on the latest ACT sky maps. In the first part of this thesis we investigate the ability of high resolution cosmic microwave background (CMB) experiments to detect hot gas in the outer regions of nearby group halos. We construct two hot gas models for the halos; a simpler adiabatic formalism with the gas described by a polytropic equation of state, and a more general gas description which incorporates feedback effects in line with constraints from X-ray observations. We calculate the thermal Sunyaev- Zel’dovich (tSZ) signal in these halos and compare it to the sensitivities of upcoming and current tSZ survey experiments such as ACT, PLANCK and the South Pole Telescope (SPT). Through the application of a multi-frequency Wiener filter, we derive mass and redshift based tSZ detectability limits for the various experiments, incorporating effects of galactic and extragalactic foregrounds as well as the CMB. In this study we find that galaxy group halos with virial masses below 1014M. can be detected at z ~< 0.05 with the mass limit dropping to 3 − 4 × 1013M. at z ~< 0.01. Probing such halos with the tSZ effect allows one to map the hot gas in the outer regions, providing a means to constrain gas processes, such as feedback, as well as the distribution of baryons in the local universe. In the fourth chapter, we extend this analysis and determine the ability of ACT to constrain galactic feedback and star formation in clusters and groups using the tSZ effect. We present a new microwave deblender, which provides a means of extracting accurate halo fluxes and radial profiles from maps of the tSZ effect. Considering various surveys that could be performed by ACT, we use multi-frequency filtering on simulated sky maps to predict how well such surveys will constrain gas properties using a Fisher matrix analysis. We find that the current ACT survey will be unable to constrain any gas parameters. However, if ACT were to survey a smaller area then we will be able to constrain feedback. Furthermore, with greater sensitivity, we will be able to place interesting constraints on the gas feedback, and baryon and stellar fractions. The fifth chapter in this thesis concerns itself with the first results of the Atacama Cosmology Telescope Project. In this section we discuss the map-making method as well as telescope beam characterisation, an understanding of which is important in any subsequent map analyses. In addition, we present maps of eight clusters observed at 148 GHz via the SZ effect, and provide flux and signal to noise estimates of the clusters. In the final chapter we present a preliminary analysis of the latest 148 GHz ACT maps from the 2008 observing season. We study the sky maps using single frequency wiener filtering, allowing for CMB, dust and correlated noise contamination. To substantiate our results, we compare the number counts, recovered fluxes and sample purity from simulated sky maps. The compounding effects of CMB and correlated noise result in high contamination levels below a signal to noise ratio of 6, however our investigation shows that above 8¾ our cluster sample is ¼ 80% pure. A cluster list containing 44 detections, of which 8 are previously known, is also presented, along with a Table listing the candidate cluster positions and fluxes. The candidate cluster catalogue will be used for follow-up studies using optical and X-ray observations. / Thesis (Ph.D.)-University of KwaZulu-Natal, Westville, 2010.
870

Econometric Analysis of Labour Market Interventions

Webb, Matthew Daniel 08 July 2013 (has links)
This thesis involves three essays that explore the theory and application of econometric analysis to labour market interventions. One essay is methodological, and two essays are applications. The first essay contributes to the literature on inference with data sets containing within-cluster correlation. The essay highlights a problem with current practices when the number of clusters is 11 or fewer. Current practices can result in p-values that are not point identified but are instead p-value intervals. The chapter provides Monte Carlo evidence to support a proposed solution to this problem. The second essay analyzes a labour market intervention within Canada--the Youth Hires program--which aimed to reduce youth unemployment. We find evidence that the program was able to increase employment among the targeted group. However, the impacts are only present for males, and we find evidence of displacement effects amongst the non-targeted group. The third essay examines a set of Graduate Retention Programs that several Canadian provinces offer. These programs are aimed at mitigating future skill shortages. Once the solution proposed in the first essay is applied, I find little evidence of the effectiveness of these programs in attracting or retaining recent graduates. / Thesis (Ph.D, Economics) -- Queen's University, 2013-07-05 15:56:33.805

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