Dissertations / Theses: 'Cardinality'

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Abdi, Mohammad Javad. "Cardinality optimization problems." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4620/.

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In this thesis, we discuss the cardinality minimization problem (CMP) and the cardinality constraint problem. Due to the NP-hardness of these problems, we discuss different computational and relaxation techniques for finding an approximate solution to these problems. We also discuss the l\(_1\)-minimization as one of the most efficient methods for solving CMPs, and we demonstrate that the l\(_1\)-minimization uses a kind of weighted l\(_2\)-minimization. We show that the reweighted l\(_j\)-minimization (j≥1) is very effective to locate a sparse solution to a linear system. Next, we show how to introduce different merit functions for sparsity, and how proper weights may reduce the gap between the performances of these functions for finding a sparse solution to an undetermined linear system. Furthermore, we introduce some effective computational approaches to locate a sparse solution for an underdetermined linear system. These approaches are based on reweighted l\(_j\)-minimization (j≥1) algorithms. We focus on the reweighted l\(_1\)-minimization, and introduce several new concave approximations to the l\(_0\)-norm function. These approximations can be employed to define new weights for reweighted l\(_1\)-minimization algorithms. We show how the change of parameters in reweighted algorithms may affect the performance of the algorithms for finding the solution of the cardinality minimization problem. In our experiments, the problem data were generated according to different statistical distributions, and we test the algorithms on different sparsity level of the solution of the problem. As a special case of cardinality constrained problems, we also discuss compressed sensing, restricted isometry property (RIP), and restricted isometry constant (RIC).

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Aslan, Murat. "The Cardinality Constrained Multiple Knapsack Problem." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610131/index.pdf.

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The classical multiple knapsack problem selects a set of items and assigns each to one of the knapsacks so as to maximize the total profit. The knapsacks have limited capacities. The cardinality constrained multiple knapsack problem assumes limits on the number of items that are to be put in each knapsack, as well. Despite many efforts on the classical multiple knapsack problem, the research on the cardinality constrained multiple knapsack problem is scarce. In this study we consider the cardinality constrained multiple knapsack problem. We propose heuristic and optimization procedures that rely on the optimal solutions of the linear programming relaxation problem. Our computational results on the large-sized problem instances have shown the satisfactory performances of our algorithms.

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Petridis, Giorgis. "Plünnecke's inequality and the cardinality of sumsets." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609666.

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Falgén, Enqvist Olle. "Cardinality estimation with a machine learning approach." Thesis, KTH, Optimeringslära och systemteori, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-288909.

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This thesis investigates how three different machine learning models perform on cardinalty estimation for sql queries. All three models were evaluated on three different data sets. The models were tested on both estimating cardinalities when the query just takes information from one table and also a two way join case. Postgresql's own cardinality estimator was used as a baseline. The evaluated models were: Artificial neural networks, random forests and extreme gradient boosted trees. What was found is that the model that performs best is the extreme gradient boosted tree with a tweedie regression loss function. To the authors knowledge, this is the first time an extreme gradient boosted tree has been used in this context.
Denna uppsats undersöker hur tre olika maskininlärningsmodeller presterar på kardinalitetsuppskattning för sql förfrågningar till en databas. Alla tre modeller utvärderades på tre olika datauppsättningar. Modellerna fick både behandla förfrågningar från en tabell, samt en sammanslagning mellan två tabeller. Postgresql's egna kardinalitetsestimerare användes som referenspunkt. De utvärderade modellerna var följande: artificiella neurala nätverk, random forests och extreme gradient boosted trees. En slutsats var att den modellen som utförde uppgiften bäst var extreme gradient boosted trees med en tweedie-regression förlustfunktion. Såvitt författaren vet är det här första gången den här typen av extreme gradient boosted tree används på denna typ av problem.

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Maryokhin, Tymur. "Data dissemination in large-cardinality social graphs." Thesis, Linnéuniversitetet, Institutionen för datavetenskap (DV), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-48268.

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Near real-time event streams are a key feature in many popular social media applications. These types of applications allow users to selectively follow event streams to receive a curated list of real-time events from various sources. Due to the emphasis on recency, relevance, personalization of content, and the highly variable cardinality of social subgraphs, it is extremely difficult to implement feed following at the scale of major social media applications. This leads to multiple architectural approaches, but no consensus has been reached as to what is considered to be an idiomatic solution. As of today, there are various theoretical approaches exploiting the dynamic nature of social graphs, but not all of them have been applied in practice. In this paper, large-cardinality graphs are placed in the context of existing research to highlight the exceptional data management challenges that are posed for large-scale real-time social media applications. This work outlines the key characteristics of data dissemination in large-cardinality social graphs, and overviews existing research and state-of-the-art approaches in industry, with the goal of stimulating further research in this direction.

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Tessaro, Amanda E. "The relationship between cardinality and understanding written number." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ39239.pdf.

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Twyford, Helen Elizabeth. "A cognitive-developmental profile of cardinality in preschoolers." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.393949.

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Qian, Chen. "Efficient cardinality counting for large-scale RFID systems /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?CSED%202008%20QIAN.

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Lo, Bianco Accou Giovanni Christian. "Estimating the number of solutions on cardinality constraints." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2019. http://www.theses.fr/2019IMTA0155/document.

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La richesse de la programmation par contraintes repose sur la très large variété des algorithmes qu’elle utilise en puisant dans les grands domaines de l’Intelligence Artificielle, de la Programmation Logique et de la Recherche Opérationnelle. Cependant, cette richesse, qui offre aux spécialistes une palette quasi-illimitée de configurations possibles pour attaquer des problèmes combinatoires, devient une frein à la diffusion plus large du paradigme, car les outils actuels sont très loin d’une boîte noire, et leur utilisation suppose une bonne connaissance du domaine, notamment en ce qui concerne leur paramétrage. Dans cette thèse, nous proposons d’analyser le comportement des contraintes de cardinalité avec des modèles probabilistes et des outils de dénombrement, pour paramétrer automatiquement les solveurs de contraintes : heuristiques de choix de variables et de choix de valeurs et stratégies de recherche
The main asset of constraint programming is its wide variety of algorithms that comes from the major areas of artificial intelligence, logic programming and operational research. It offers specialists a limitless range of possible configurations to tackle combinatorial problems, but it becomes an obstacle to the wider diffusion of the paradigm. The current tools are very far from being used as a black-box tool, and it assumes a good knowledge of the field, in particular regarding the parametrization of solvers.In this thesis, we propose to analyze the behavior of cardinality constraints with probabilistic models and counting tools, to automatically parameterize constraint solvers: heuristics of choice of variables and choice of values and search strategies

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Silvanus, Jannik [Verfasser]. "Improved Cardinality Bounds for Rectangle Packing Representations / Jannik Silvanus." Bonn : Universitäts- und Landesbibliothek Bonn, 2019. http://d-nb.info/1188726226/34.

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Isaksson, Erica. "Cardinality for optical orthogonal codes with variable length and weight." Thesis, Linköping University, Department of Electrical Engineering, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7672.

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To let many users beneﬁt from the high speed communication in an optical ﬁber, a way to share the channel is needed. One way to share the channel between the users is the multiple access technique of Code Division Multiple Access, CDMA. This technique is based on coding. By assigning the users diﬀerent codewords, the receiver is able to distinguish the information sent from each user. One family of codes suitable to use in a ﬁber optic network is the constant weight Optical Orthogonal Codes, OOC.

To inﬂuence the users interference tolerability it is possible to assign the users codewords of the same length but with diﬀerent weights. By letting the users have codewords of diﬀerent length it is possible to have diﬀerent data rates in the system. These two versions of optical orthogonal codes, with variable length and weight, are investigated in this thesis for their cardinality. The variable weight and variable length codes were created by combining optical orthogonal codes with diﬀerent parameters.

I have found that for variable length OOC:s of weight 2 it seems to be possible to increase the cardinality of a code, but for codes with higer weights than that, it is better that all users are assigned codewords of the same length. But since an upper bound for the cardinality of these types of codes has not been found, it is not possible to verify if this conclusion is correct. For variable weight OOC:s it is found that it is only possible to increase the cardinality of small, not optimal, codes. For codes including many codewords it is rarely possible to include more codewords without breaking the conditions on cross correlation between the codewords.

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Cakir, Kadir. "Counting ability and the understanding of cardinality in preschool children." Thesis, University of Warwick, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300714.

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Krishnan, Bharath Kumar. "A multiscale approximation algorithm for the cardinality constrained knapsack problem." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/34612.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2006.
Includes bibliographical references (leaves 83-86).
I develop a multiscale approximation algorithm for the cardinality constrained knapsack problem. The algorithm consists of three steps: a rounding and reduction step where a hierarchical representation of the problem data ranging from coarse to fine is generated, a solution step where a coarse solution is computed, and a refinement step where the accuracy of the solution is improved by refining the problem representation. I demonstrate that the algorithm is fully polynomial with a runtime complexity that improves upon the previous best known fully polynomial approximation scheme. Through an extensive computational study, I show that the running times of the algorithm is less than or equal to that of a commercial integer programming package with little loss in solution accuracy.
by Bharath Kumar Krishnan.
Ph.D.

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Neamatian, Monemi Rahimeh. "Fixed cardinality linear ordering problem, polyhedral studies and solution methods." Thesis, Clermont-Ferrand 2, 2014. http://www.theses.fr/2014CLF22516/document.

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Le problème d’ordre linéaire (LOP) a reçu beaucoup d’attention dans différents domaines d’application, allant de l’archéologie à l’ordonnancement en passant par l’économie et même de la psychologie mathématique. Ce problème est aussi connu pour être parmi les problèmes NP-difficiles. Nous considérons dans cette thèse une variante de (LOP) sous contrainte de cardinalité. Nous cherchons donc un ordre linéaire d’un sous-ensemble de sommets du graphe de préférences de cardinalité fixée et de poids maximum. Ce problème, appelé (FCLOP) pour ’fixed-cardinality linear ordering problem’, n’a pas été étudié en tant que tel dans la littérature scientifique même si plusieurs applications dans les domaines de macro-économie, de classification dominante ou de transport maritime existent concrètement. On retrouve en fait ses caractéristiques dans les modèles étendus de sous-graphes acycliques. Le problème d’ordre linéaire est déjà connu comme un problème NP-difficile et il a donné lieu à de nombreuses études, tant théoriques sur la structure polyédrale de l’ensemble des solutions réalisables en variables 0-1 que numériques grâce à des techniques de relaxation et de séparation progressive. Cependant on voit qu’il existe de nombreux cas dans la littérature, dans lesquelles des solveurs de Programmation Linéaire en nombres entiers comme CPLEX peuvent en résoudre certaines instances en moins de 10 secondes, mais une fois que la cardinalité est limitée, ces mêmes instances deviennent très difficiles à résoudre. Sur les aspects polyédraux, nous avons étudié le polytope de FCLOP, défini plusieurs classes d’inégalités valides et identifié la dimension ainsi que certaines inégalités qui définissent des facettes pour le polytope de FCLOP. Nous avons introduit un algorithme Relax-and-Cut basé sur ces résultats pour résoudre les instances du problème. Dans cette étude, nous nous sommes également concentrés sur la relaxation Lagrangienne pour résoudre ces cas difficiles. Nous avons étudié différentes stratégies de relaxation et nous avons comparé les bornes duales par rapport à la consolidation obtenue à partir de chaque stratégie de relâcher les contraintes afin de détecter le sous-ensemble des contraintes le plus approprié. Les résultats numériques montrent que nous pouvons trouver des bornes duales de très haute qualité. Nous avons également mis en place une méthode de décomposition Lagrangienne. Dans ce but, nous avons décomposé le modèle de FCLOP en trois sous-problèmes (au lieu de seulement deux) associés aux contraintes de ’tournoi’, de ’graphes sans circuits’ et de ’cardinalité’. Les résultats numériques montrent une amélioration significative de la qualité des bornes duales pour plusieurs cas. Nous avons aussi mis en oeuvre une méthode de plans sécants (cutting plane algorithm) basée sur la relaxation pure des contraintes de circuits. Dans cette méthode, on a relâché une partie des contraintes et on les a ajoutées au modèle au cas où il y a des de/des violations. Les résultats numériques montrent des performances prometteuses quant à la réduction du temps de calcul et à la résolution d’instances difficiles hors d’atteinte des solveurs classiques en PLNE
Linear Ordering Problem (LOP) has receive significant attention in different areas of application, ranging from transportation and scheduling to economics and even archeology and mathematical psychology. It is classified as a NP-hard problem. Assume a complete weighted directed graph on V n , |V n |= n. A permutation of the elements of this finite set of vertices is a linear order. Now let p be a given fixed integer number, 0 ≤ p ≤ n. The p-Fixed Cardinality Linear Ordering Problem (FCLOP) is looking for a subset of vertices containing p nodes and a linear order on the nodes in S. Graphically, there exists exactly one directed arc between every pair of vertices in an LOP feasible solution, which is also a complete cycle-free digraph and the objective is to maximize the sum of the weights of all the arcs in a feasible solution. In the FCLOP, we are looking for a subset S ⊆ V n such that |S|= p and an LOP on these S nodes. Hence the objective is to find the best subset of the nodes and an LOP over these p nodes that maximize the sum of the weights of all the arcs in the solution. Graphically, a feasible solution of the FCLOP is a complete cycle-free digraph on S plus a set of n − p vertices that are not connected to any of the other vertices. There are several studies available in the literature focused on polyhedral aspects of the linear ordering problem as well as various exact and heuristic solution methods. The fixed cardinality linear ordering problem is presented for the first time in this PhD study, so as far as we know, there is no other study in the literature that has studied this problem. The linear ordering problem is already known as a NP-hard problem. However one sees that there exist many instances in the literature that can be solved by CPLEX in less than 10 seconds (when p = n), but once the cardinality number is limited to p (p < n), the instance is not anymore solvable due to the memory issue. We have studied the polytope corresponding to the FCLOP for different cardinality values. We have identified dimension of the polytope, proposed several classes of valid inequalities and showed that among these sets of valid inequalities, some of them are defining facets for the FCLOP polytope for different cardinality values. We have then introduced a Relax-and-Cut algorithm based on these results to solve instances of the FCLOP. To solve the instances of the problem, in the beginning, we have applied the Lagrangian relaxation algorithm. We have studied different relaxation strategies and compared the dual bound obtained from each case to detect the most suitable subproblem. Numerical results show that some of the relaxation strategies result better dual bound and some other contribute more in reducing the computational time and provide a relatively good dual bound in a shorter time. We have also implemented a Lagrangian decomposition algorithm, decom-6 posing the FCLOP model to three subproblems (instead of only two subproblems). The interest of decomposing the FCLOP model to three subproblems comes mostly from the nature of the three subproblems, which are relatively quite easier to solve compared to the initial FCLOP model. Numerical results show a significant improvement in the quality of dual bounds for several instances. We could also obtain relatively quite better dual bounds in a shorter time comparing to the other relaxation strategies. We have proposed a cutting plane algorithm based on the pure relaxation strategy. In this algorithm, we firstly relax a subset of constraints that due to the problem structure, a very few number of them are active. Then in the course of the branch-and-bound tree we verify if there exist any violated constraint among the relaxed constraints or. Then the characterized violated constraints will be globally added to the model. (...)

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Ruaro, Lorenzo. "Cardinalità di insiemi e numeri cardinali." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10081/.

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Pendharkar, Yogesh. "A Hybrid Non-Clustered Bitmap Index for Supporting High Cardinality Attributes." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1262203195.

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Thiyagarajah, Murali. "Attribute cardinality maps, new query result size estimation techniques for database systems." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0007/NQ42810.pdf.

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Thiyagarajah, Murali (Muralitharam) Carleton University Dissertation Computer Science. "Attribute cardinality maps; new query result size estimation techniques for database systems." Ottawa, 1999.

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Asathulla, Mudabir Kabir. "A Sparsification Based Algorithm for Maximum-Cardinality Bipartite Matching in Planar Graphs." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/88080.

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Matching is one of the most fundamental algorithmic graph problems. Many variants of matching problems have been studied on different classes of graphs, the one of special interest to us being the Maximum Cardinality Bipartite Matching in Planar Graphs. In this work, we present a novel sparsification based approach for computing maximum/perfect bipartite matching in planar graphs. The overall complexity of our algorithm is O(n^{6/5} log^2 {n}) where n is the number of vertices in the graph, bettering the O(n^{3/2}) time achieved independently by Hopcroft-Karp algorithm and by Lipton and Tarjan divide and conquer approach using planar separators. Our algorithm combines the best of both these standard algorithms along with our sparsification technique and rich planar graph properties to achieve the speed up. Our algorithm is not the fastest, with the existence of O(nlog^3 {n}) algorithm based on max-flow reduction.
MS

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Cara, Francesco. "Modeling the child's development of cardinality : from counting to conservation of number." Thesis, University of Edinburgh, 1990. http://hdl.handle.net/1842/23779.

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This thesis proposes a domain-specific framework to deal with some of the problems of cognitive development raised by Post-Piagetian research, in particular early competence and heterogeneity in across-domains performance. The theoretical framework is explored in relation to the development of the domain of cardinal number: from counting to precocious number conservation to standard conservation. The results of three empirical studies support the interpretation that a same structure specialized in processing numerical information becomes operational on contents of increasing complexity: 1. on individual sets (as in set reproduction tasks); 2. on two or more sets (as in set comparison and modified conservation tasks); 3. on sets of sets (as in the Piagetian number conservation task). The process by which the child discovers the import of the number-structure on new contents is modeled as a semantic process that transforms cardinal representations, entertained as irrelevant, into relevant representations. This transformation proceeds in a stage-like way which, at each stage, reveals new facts about number and brings about a restructuring and extension of the cardinal number concept.

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Seipp, Florian [Verfasser]. "On Adjacency, Cardinality, and Partial Dominance in Discrete Multiple Objective Optimization / Florian Seipp." München : Verlag Dr. Hut, 2013. http://d-nb.info/1045125679/34.

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Li, Yibo. "Solving cardinality constrained portfolio optimisation problem using genetic algorithms and ant colony optimisation." Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/10867.

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In this thesis we consider solution approaches for the index tacking problem, in which we aim to reproduces the performance of a market index without purchasing all of the stocks that constitute the index. We solve the problem using three different solution approaches: Mixed Integer Programming (MIP), Genetic Algorithms (GAs), and Ant-colony Optimization (ACO) Algorithm by limiting the number of stocks that can be held. Each index is also assigned with different cardinalities to examine the change to the solution values. All of the solution approaches are tested by considering eight market indices. The smallest data set only consists of 31 stocks whereas the largest data set includes over 2000 stocks. The computational results from the MIP are used as the benchmark to measure the performance of the other solution approaches. The Computational results are presented for different solution approaches and conclusions are given. Finally, we implement post analysis and investigate the best tracking portfolios achieved from the three solution approaches. We summarise the findings of the investigation, and in turn, we further improve some of the algorithms. As the formulations of these problems are mixed-integer linear programs, we use the solver ‘Cplex’ to solve the problems. All of the programming is coded in AMPL.

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Lubczonok, Pawel. "Aspects of fuzzy spaces with special reference to cardinality, dimension, and order-homomorphisms." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005213.

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Aspects of fuzzy vector spaces and fuzzy groups are investigated, including linear independence, basis, dimension, group order, finitely generated groups and cyclic groups. It was necessary to consider cardinality of fuzzy sets and related issues, which included a question of ways in which to define functions between fuzzy sets. Among the results proved, are the additivity property of dimension for fuzzy vector spaces, Lagrange's Theorem for fuzzy groups ( the existing version of this theorem does not take fuzziness into account at all), a compactness property of finitely generated fuzzy groups and an extension of an earlier result on the order-homomorphisms. An open question is posed with regard to the existence of a basis for an arbitrary fuzzy vector space.

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Linnell, Margaret Elizabeth. "The influence of social interaction on the development of cardinality in pre-school children." Thesis, University of Portsmouth, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264674.

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Kamnang, Wanko Patrick. "Optimisation des requêtes skyline multidimensionnelles." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0010/document.

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Dans le cadre de la sélection de meilleurs éléments au sein d’une base de données multidimensionnelle, plusieurs types de requêtes ont été définies. L’opérateur skyline présente l’avantage de ne pas nécessiter la définition d’une fonction de score permettant de classer lesdits éléments. Cependant, la propriété de monotonie que cet opérateur ne présente pas, rend non seulement (i) difficile l’optimisation de ses requêtes dans un contexte multidimensionnel, mais aussi (ii) presque imprévisible la taille du résultat des requêtes. Ce travail se propose, dans un premier temps, d’aborder la question de l’estimation de la taille du résultat d’une requête skyline donnée, en formulant des estimateurs présentant de bonnes propriétés statistiques(sans biais ou convergeant). Ensuite, il fournit deux approches différentes à l’optimisation des requêtes skyline. La première reposant sur un concept classique des bases de données qui est la dépendance fonctionnelle. La seconde se rapprochant des techniques de compression des données. Ces deux techniques trouvent leur place au sein de l’état de l’art comme le confortent les résultats expérimentaux.Nous abordons enfin la question de requêtes skyline au sein de données dynamiques en adaptant l’une de nos solutions précédentes dans cet intérêt
As part of the selection of the best items in a multidimensional database,several kinds of query were defined. The skyline operator has the advantage of not requiring the definition of a scoring function in order to classify tuples. However, the property of monotony that this operator does not satify, (i) makes difficult to optimize its queries in a multidimensional context, (ii) makes hard to estimate the size of query result. This work proposes, first, to address the question of estimating the size of the result of a given skyline query, formulating estimators with good statistical properties (unbiased or convergent). Then, it provides two different approaches to optimize multidimensional skyline queries. The first leans on a well known database concept: functional dependencies. And the second approach looks like a data compression method. Both algorithms are very interesting as confirm the experimental results. Finally, we address the issue of skyline queries in dynamic data by adapting one of our previous solutions in this goal

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Hadish, Mulugeta. "Extended Multidimensional Conceptual Spaces in Document Classification." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1227158181.

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Sadler, Andrew John. "Strengthening finite set constraint solvers through active use of problem structure, symmetries and cardinality restrictions." Thesis, Imperial College London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418308.

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Hill, Joshua Erin. "On Calculating the Cardinality of the Value Set of a Polynomial (and some related problems)." Thesis, University of California, Irvine, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3646731.

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We prove a combinatorial identity that relates the size of the value set of a map with the sizes of various iterated fiber products by this map. This identity is then used as the basis for several algorithms that calculate the size of the value set of a polynomial for a broad class of algebraic spaces, most generally an algorithm to calculate the size of the value set of a suitably well-behaved morphism between "nice" affine varieties defined over a finite field. In particular, these algorithms specialize to the case of calculating the size of the value set of a polynomial, viewed as a map between finite fields. These algorithms operate in deterministic polynomial time for fixed input polynomials (thus a fixed number of variables and polynomial degree), so long as the characteristic of the field grows suitably slowly as compared to the other parameters.

Each of these algorithms also produces a fiber signature for the map, which for each positive integer j, specifies how many points in the image have fibers of cardinality exactly j.

We adapt and analyze the zeta function calculation algorithms due to Lauder-Wan and Harvey, both as point counting algorithms and as algorithms for computation of one or many zeta functions.

These value set cardinality calculation algorithms extend to amortized cost algorithms that offer dramatic computational complexity advantages, when the computational cost is amortized over all the results produced. The last of these amortized algorithms partially answers a conjecture of Wan, as it operates in time that is polynomial in log q per value set cardinality calculated.

For the value set counting algorithms, these are the first such results, and offer a dramatic improvement over any previously known approach.

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Nguyen, Thanh Chuyen. "Studies on Algorithms for Tag Identification and Tag Set Cardinality Estimation in Radio Frequency Identification Systems." 京都大学 (Kyoto University), 2013. http://hdl.handle.net/2433/174849.

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Barksten, Martin. "Evaluating the effect of cardinality estimates on two state-of-the-art query optimizer's selection of access method." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-189892.

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This master thesis concern relational databases and their query optimizer’s sensitivity to cardinality estimates and the e!ect the quality of the estimate has on the number of different access methods used for the same relation. Two databases are evaluated — PostgreSQL and MariaDB — on a real-world dataset to provide realistic results. The evaluation was done via a tool implemented in Clojure and tests were conducted on a query and subsets of it with varying sample sizes used when estimating cardinality. The results indicate that MariaDB’s query optimizer is less sensitive to cardinality estimates and for all tests select the same access methods, regardless of the quality of the cardinality estimate. This stands in contrast to PostgreSQL’s query optimizer which will vary between using an index or doing a full table scan depending on the estimated cardinality. Finally, it is also found that the predicate value used in the query a!ects the access method used. Both PostgreSQL and MariaDB are found sensitive to this property, with MariaDB having the largest number of di!erent access methods used depending on predicate value.
Detta examensarbete behandlar relationella databaseer och hur stor påverkan kvaliteten på den uppskattade kardinaliteten har på antalet olika metoder som används för att hämta data från samma relation. Två databaser testades — PostgreSQL och MariaDB — på ett verkligt dataset för att ge realistiska resultat. Utvärderingen gjordes med hjälp av ett verktyg implementerat i Clojure och testerna gjordes på en query, och delvarianter av den, med varierande stora sample sizes för kardinalitetsuppskattningen. Resultaten indikerar att MariaDBs query optimizer inte påverkas av kardinalitetsuppskattningen, för alla testerna valde den samma metod för att hämta datan. Detta skiljer sig mot PostgreSQLs query optimizer som varierade mellan att använda sig av index eller göra en full table scan beroende på den uppskattade kardinaliteten. Slutligen pekade även resultaten på att båda databasernas query optimizers varierade metod för att hämta data beroende på värdet i predikatet som användes i queryn.

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Bhojwani, Praveen Sunder. "Mapping multimode system communication to a network-on-a-chip (NoC)." Texas A&M University, 2003. http://hdl.handle.net/1969.1/299.

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Decisions regarding the mapping of system-on-chip (SoC) components onto a NoC become more difficult with increasing complexity of system design. These complex systems capable of providing multiple functionalities tend to operate in multiple modes of operation. Modeling the system communication in these multimodes aids in efficient system design. This research provides a heuristic that gives a flexible mapping solution of the multimode system communications onto the NoC topology of choice. The solution specifies the immediate neighbors of the SoC components and the routes taken by all communications in the system. We validate the mapping results with a network-on-chip simulator (NoCSim). This thesis also investigates the cost associated with the interfacing of the components to the NoC. With the goal of reducing communication latency, we examine the packetization strategies in the NoC communication. Three schemes of implementations were analyzed, and the costs in terms of latency, and area were projected through actual synthesis.

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32

Bucher, Max [Verfasser], Alexandra [Akademischer Betreuer] Schwartz, and Christian [Akademischer Betreuer] Kanzow. "Optimality Conditions and Numerical Methods for a Continuous Reformulation of Cardinality Constrained Optimization Problems / Max Bucher ; Alexandra Schwartz, Christian Kanzow." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2018. http://d-nb.info/1167926323/34.

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33

Enflo, Karin. "Measures of Freedom of Choice." Doctoral thesis, Uppsala universitet, Avdelningen för praktisk filosofi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-179078.

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This thesis studies the problem of measuring freedom of choice. It analyzes the concept of freedom of choice, discusses conditions that a measure should satisfy, and introduces a new class of measures that uniquely satisfy ten proposed conditions. The study uses a decision-theoretical model to represent situations of choice and a metric space model to represent differences between options. The first part of the thesis analyzes the concept of freedom of choice. Different conceptions of freedom of choice are categorized into evaluative and non-evaluative, as well as preference-dependent and preference-independent kinds. The main focus is on the three conceptions of freedom of choice as cardinality of choice sets, representativeness of the universal set, and diversity of options, as well as the three conceptions of freedom of rational choice, freedom of eligible choice, and freedom of evaluated choice. The second part discusses the conceptions, together with conditions for a measure and a variety of measures proposed in the literature. The discussion mostly focuses on preference-independent conceptions of freedom of choice, in particular the diversity conception. Different conceptions of diversity are discussed, as well as properties that could affect diversity, such as the cardinality of options, the differences between the options, and the distribution of differences between the options. As a result, the diversity conception is accepted as the proper explication of the concept of freedom of choice. In addition, eight conditions for a measure are accepted. The conditions concern domain-insensitivity, strict monotonicity, no-choice situations, dominance of differences, evenness, symmetry, spread of options, and limited function growth. None of the previously proposed measures satisfy all of these conditions. The third part concerns the construction of a ratio-scale measure that satisfies the accepted conditions. Two conditions are added regarding scale-independence and function growth proportional to cardinality. Lastly, it is shown that only one class of measures satisfy all ten conditions, given an additional assumption that the measures should be analytic functions with non-zero partial derivatives with respect to some function of the differences. These measures are introduced as the Ratio root measures.

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34

Kreber, Dennis [Verfasser], Sven de [Akademischer Betreuer] Vries, Jan Pablo [Akademischer Betreuer] Burgard, Sven de [Gutachter] Vries, Jan Pablo [Gutachter] Burgard, and Christoph [Gutachter] Buchheim. "Cardinality-Constrained Discrete Optimization for Regression / Dennis Kreber ; Gutachter: Sven de Vries, Jan Pablo Burgard, Christoph Buchheim ; Sven de Vries, Jan Pablo Burgard." Trier : Universität Trier, 2019. http://d-nb.info/1197809198/34.

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35

Cerda, Reyes Patricio. "Apprentissage statistique à partir de variables catégorielles non-uniformisées Similarity encoding for learning with dirty categorical variables Encoding high-cardinality string categorical variables." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS470.

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Les données de type tabulaire contiennent souvent des variables catégorielles, considérées comme des entrées non numériques avec un nombre fixe et limité d'éléments uniques, appelés catégories. De nombreux algorithmes d’apprentissage statistique nécessitent une représentation numérique des variables catégorielles. Une étape d'encodage est donc nécessaire pour transformer ces entrées en vecteurs. Pour cela, plusieurs stratégies existent, dont la plus courante est celle de l'encodage one-hot, qui fonctionne bien dans le cadre de l'analyse statistique classique (en termes de puissance de prédiction et d'interprétation) lorsque le nombre de catégories reste faible. Cependant, les données catégorielles non-uniformisées présentent le risque d'avoir une grande cardinalité et des redondances. En effet, les entrées peuvent partager des informations sémantiques et/ou morphologiques, et par conséquent, plusieurs entrées peuvent refléter la même entité. Sans une étape de nettoyage ou d'agrégation au préalable, les méthodes d'encodage courantes peuvent perdre en efficacité du fait d'une représentation vectorielle erronée. En outre, le risque d'obtenir des vecteurs de très grandes dimensions croit avec la quantité de données, ce qui empêche leur utilisation dans l'analyse de données volumineuses. Dans ce document, nous étudions une série de méthodes d’encodage qui permettent de travailler directement sur des variables catégorielles à grande cardinalité, sans qu'il soit nécessaire de les traiter en amont. A l'aide d'expériences menées sur des données réelles et simulées, nous démontrons que les méthodes proposées dans le cadre de cette thèse améliorent l'apprentissage supervisé et ce, en autre, du fait de leur capacité à capturer correctement l'information morphologique des entrées. Même avec des données volumineuses, ces méthodes s'avèrent être performantes, et dans certains cas, elles génèrent des vecteurs facilement interprétables. Par conséquent, nos méthodes peuvent être appliquées à l'apprentissage statistique automatique (AutoML) sans aucune intervention humaine
Tabular data often contain columns with categorical variables, usually considered as non-numerical entries with a fixed and limited number of unique elements or categories. As many statistical learning algorithms require numerical representations of features, an encoding step is necessary to transform categorical entries into feature vectors, using for instance one-hot encoding. This and other similar strategies work well, in terms of prediction performance and interpretability, in standard statistical analysis when the number of categories is small. However, non-curated data give rise to string categorical variables with a very high cardinality and redundancy: the string entries share semantic and/or morphological information, and several entries can reflect the same entity. Without any data cleaning or feature engineering step, common encoding methods break down, as they tend to lose information in their vectorial representation. Also, they can create high-dimensional feature vectors, which prevent their usage in large scale settings. In this work, we study a series of categorical encodings that remove the need for preprocessing steps on high-cardinality string categorical variables. An ideal encoder should be: scalable to many categories; interpretable to end users; and capture the morphological information contained in the string entries. Experiments on real and simulated data show that the methods we propose improve supervised learning, are adapted to large-scale settings, and, in some cases, create feature vectors that are easily interpretable. Hence, they can be applied in Automated Machine Learning (AutoML) pipelines in the original string entries without any human intervention

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36

Borges, Bruno Andrade. "O infinito na matemática." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/55/55136/tde-08042015-143010/.

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Nesta dissertação, abordaremos os dois tipos de infinitos existentes: o infinito potencial e o infinito actual. Apresentaremos algumas situações, exemplos que caracterizam cada um desses dois tipos. Focaremo-nos no infinito actual, com o qual discutiremos alguns dos desafios encontrados na teoria criada por Cantor sobre este assunto. Mostraremos também sua importância e a diferença entre este e o infinito potencial. Com isso, buscamos fazer com que o professor compreenda adequadamente os fundamentos matemáticos necessários para que trabalhe, ensine e motive apropriadamente seus alunos no momento em que o infinito e conjuntos infinitos são discutidos em aula. Desta forma, buscamos esclarecer os termos usados e equívocos comuns cometidos por alunos e também professores, muitas vezes enganados ou confundidos pelo senso comum.
In this dissertation, we will discuss the two types of infinities: the potential infinity and the actual infinity. We will present some situations, examples that characterize each of these two types. We will focus on the actual infinity, with which we will discuss some of the challenges found in the theory created by Cantor on this subject. We will also show its importance and the difference between this and the potential infinity. Thus, we seek to make teachers properly understand the mathematical foundations necessary for them to work, teach and properly motivate their students at the time the infinity and infinite sets are discussed in class. In this way, we seek to clarify the terms used and common mistakes made by students and also teachers, so often misguided or confused by common sense.

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37

Karlsson, Andreas. "Simulation of a CDMA system based on optical orthogonal codes." Thesis, Linköping University, Department of Electrical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2300.

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To take advantage of the high speed in an optic fiber, one of the basic concept in fiber optic communication is to allow several users to simultaneously transmit data over the channel. One technique that provides multiple access is it fiber optic-code division multiple access (FO-CDMA). In FO-CDMA each user is assigned one or more signature sequences called codewords, which are subsets of a type of optical orthogonal code (OOC). The channel input/output consists of the superposition of several users codewords and at the receiver end an optical correlator extracts the information.

In the parallel code constructions, presented in this report, each user j is assigned a subset Cj from a code C. The subsets are disjoint and their union is the whole set C. A new way to map the information bits is to insert up to L zeros before each codeword from Cj and let this represent information aswell. This gives high rates for active users but an investigation is needed to ensure that this does not compromise the systems wanted property of sending information with a small probability of errors for all users. Therefore a simulation environment has been implemented in Matlab.

The result from these simulations shows that BER for the L parallel codes is acceptable and not much higher than for the traditional constructions. Because of the higher rate these construction should be preferred but an analysis if a hardware implementation is possible.

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38

Dias, Carlos Henrique. "Um novo algoritmo genetico para a otimização de carteiras de investimento com restrições de cardinalidade." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307124.

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Orientador: Francisco de Assis Magalhães Gomes Neto
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
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Resumo: Este trabalho tem por finalidade a determinação da fronteira eficiente de investimento através da otimização do modelo de média-variância com restrições de cardinalidade e limite inferior de investimento. Por tratar-se de um problema inteiro e não linear, cuja solução exata é de difícil obtenção, optamos por empregar um algoritmo genético, na linha desenvolvida por Chang et al. [3], que até hoje serve como referência para a determinação da fronteira eficiente de Pareto para problemas de otimização de investimentos. Entretanto, verificamos que o algoritmo proposto por Chang et al. apresenta uma distribuição não uniforme na geração de soluções aleatórias. Para contornar esse problema, introduzimos um novo esquema de geração de cromossomos, baseado na discretização do espaço, que permite a geração de soluções que satisfazem diretamente a restrição de montante total aplicado. Com essa nova abordagem, foi possível definir operadores de seleção, crossover e mutação bastante eficientes. Os resultados obtidos mostram que o novo algoritmo é mais robusto que aquele proposto por Chang et al
Abstract: In this work we consider the problem of determining of the efficient frontier of a portfolio using the mean-variance model subject to a cardinality constrain and to lower bounds on the amount invested in the selected assets. As this nonlinear integer programming problem is hard to solve exactly, we use a genetic algorithm, following the lines described by Chang et al. [3], still considered as a reference in the field. However, as the feasible solutions generated by the algorithm of Chang et al. are not uniformly distributed over the solution set, we introduce a new scheme for defining the chromosomes, based on the discretization of the feasible region, so that the amount invested always sum up to one for every solution obtained by the algorithm. This new approach allows us to define very efficient selection, crossover and mutation procedures. The numerical results obtained so far show that the new method is more robust than the one proposed by Chang et al
Mestrado
Otimização
Mestre em Matemática Aplicada

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39

Quimper, Claude-Guy. "Efficient Propagators for Global Constraints." Thesis, University of Waterloo, 2006. http://hdl.handle.net/10012/2916.

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We study in this thesis three well known global constraints. The All-Different constraint restricts a set of variables to be assigned to distinct values. The global cardinality constraint (GCC) ensures that a value v is assigned to at least l_v variables and to at most u_v variables among a set of given variables where l_v and u_v are non-negative integers such that l_v ≤ u_v. The Inter-Distance constraint ensures that all variables, among a set of variables x₁, . . . , x_n, are pairwise distant from p, i. e. |x_i - x_j| ≥ p for all i ≠ j. The All-Different constraint, the GCC, and the Inter-Distance constraint are largely used in scheduling problems. For instance, in scheduling problems where tasks with unit processing time compete for a single resource, we have an All-Different constraint on the starting time variables. When there are k resources, we have a GCC with l_v = 0 and u_v = k over all starting time variables. Finally, if tasks have processing time t and compete for a single resource, we have an Inter-Distance constraint with p = t over all starting time variables. We present new propagators for the All-Different constraint, the GCC, and the Inter-Distance constraint i. e. , new filtering algorithms that reduce the search space according to these constraints. For a given consistency, our propagators outperform previous propagators both in practice and in theory. The gains in performance are achieved through judicious use of advanced data structures combined with novel results on the structural properties of the constraints.

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40

Dahlström, Magnus. "Mängdlära och kardinalitet : Cantors paradis." Thesis, Växjö University, School of Mathematics and Systems Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-6.

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This paper is about basic set theory and cardinalities for infinite sets. One of the results are that the line R and the plane R2 contains exactly the same number of points. Because of that the set theory is described with a formal language this the paper has an appendix about formal languages.

Denna uppsats behandlar grundläggande mängdlära och inriktar sig sedan på kardinaliteter för oändliga mängder. Bland de resultat som redovisas finns bland annat resultatet som säger att linjen R och planet R2 innehåller precis lika många punkter. Då mängdläran beskrivs av ett formellt språk så innehåller uppsatsen en bilaga om formella språk.

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41

Raghavan, Venkatesh. "Supporting Multi-Criteria Decision Support Queries over Disparate Data Sources." Digital WPI, 2012. https://digitalcommons.wpi.edu/etd-dissertations/120.

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In the era of "big data revolution," marked by an exponential growth of information, extracting value from data enables analysts and businesses to address challenging problems such as drug discovery, fraud detection, and earthquake predictions. Multi-Criteria Decision Support (MCDS) queries are at the core of big-data analytics resulting in several classes of MCDS queries such as OLAP, Top-K, Pareto-optimal, and nearest neighbor queries. The intuitive nature of specifying multi-dimensional preferences has made Pareto-optimal queries, also known as skyline queries, popular. Existing skyline algorithms however do not address several crucial issues such as performing skyline evaluation over disparate sources, progressively generating skyline results, or robustly handling workload with multiple skyline over join queries. In this dissertation we thoroughly investigate topics in the area of skyline-aware query evaluation. In this dissertation, we first propose a novel execution framework called SKIN that treats skyline over joins as first class citizens during query processing. This is in contrast to existing techniques that treat skylines as an "add-on," loosely integrated with query processing by being placed on top of the query plan. SKIN is effective in exploiting the skyline characteristics of the tuples within individual data sources as well as across disparate sources. This enables SKIN to significantly reduce two primary costs, namely the cost of generating the join results and the cost of skyline comparisons to compute the final results. Second, we address the crucial business need to report results early; as soon as they are being generated so that users can formulate competitive decisions in near real-time. On top of SKIN, we built a progressive query evaluation framework ProgXe to transform the execution of queries involving skyline over joins to become non-blocking, i.e., to be progressively generating results early and often. By exploiting SKIN's principle of processing query at multiple levels of abstraction, ProgXe is able to: (1) extract the output dependencies in the output spaces by analyzing both the input and output space, and (2) exploit this knowledge of abstract-level relationships to guarantee correctness of early output. Third, real-world applications handle query workloads with diverse Quality of Service (QoS) requirements also referred to as contracts. Time sensitive queries, such as fraud detection, require results to progressively output with minimal delay, while ad-hoc and reporting queries can tolerate delay. In this dissertation, by building on the principles of ProgXe we propose the Contract-Aware Query Execution (CAQE) framework to support the open problem of contract driven multi-query processing. CAQE employs an adaptive execution strategy to continuously monitor the run-time satisfaction of queries and aggressively take corrective steps whenever the contracts are not being met. Lastly, to elucidate the portability of the core principle of this dissertation, the reasoning and query processing at different levels of data abstraction, we apply them to solve an orthogonal research question to auto-generate recommendation queries that facilitate users in exploring a complex database system. User queries are often too strict or too broad requiring a frustrating trial-and-error refinement process to meet the desired result cardinality while preserving original query semantics. Based on the principles of SKIN, we propose CAPRI to automatically generate refined queries that: (1) attain the desired cardinality and (2) minimize changes to the original query intentions. In our comprehensive experimental study of each part of this dissertation, we demonstrate the superiority of the proposed strategies over state-of-the-art techniques in both efficiency, as well as resource consumption.

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42

Berlin, Martin. "Essays on the Determinants and Measurement of Subjective Well-Being." Doctoral thesis, Stockholms universitet, Nationalekonomiska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-142560.

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This thesis consists of four self-contained essays in economics, all concerned with different aspects of subjective well-being. The abstracts of the four studies are as follows. Beyond Income: The Importance for Life Satisfaction of Having Access to a Cash Margin. We study how life satisfaction among adult Swedes is influenced by having access to a cash margin, i.e. a moderate amount of money that could be acquired on short notice either through own savings, by loan from family or friends, or by other means. We find that cash margin is a strong and robust predictor of life satisfaction, also when controlling for individual fixed effects and socio-economic conditions, including income. Decomposing Variation in Daily Feelings: The Role of Time Use and Individual Characteristics. I explore the potential of using time-use data for understanding variation in affective well-being. Using the Princeton Affect and Time Survey, I decompose variation in daily affect into explained and unexplained within- and between person variation. Time use is found to mostly account for within-variation. Hence, its explanatory power is largely additive to that of individual characteristics. The explanatory power of time use is small, however. Activities only account for 1–7% of the total variation and this is not increased much by adding contextual variables. The Association Between Life Satisfaction and Affective Well-Being. We estimate the correlation between life satisfaction and affect — two conceptually distinct dimensions of subjective well-being. We propose a simple model that distinguishes between a stable and a transitory component of affect, and which also accounts for measurement error in self-reports of both variables, including current-mood bias effects on life satisfaction judgments. The model is estimated using momentarily measured well-being data, from an experience sampling survey that we conducted on a population sample of Swedes aged 18–50 (n=252). Our main estimates of the correlation between life satisfaction and long-run affective well-being range between 0.78 and 0.91, indicating a stronger convergence between these variables than many previous studies that do not account for measurement issues. Do OLS and Ordinal Happiness Regressions Yield Different Results? A Quantitative Assessment. Self-reported subjective well-being scores are often viewed as ordinal variables, but the conventional wisdom has it that OLS and ordered regression models (e.g. ordered probit) produce similar results when applied to such data. This claim has rarely been assessed formally, however, in particular with respect to quantifying the differences. I shed light on this issue by comparing the results from OLS and different ordered regression models, in terms of both statistical and economic significance, and across data sets with different response scales for measuring life satisfaction. The results are mixed. The differences between OLS, probit and logit estimates are typically small when the response scale has few categories, but larger, though not huge, when an 11-point scale is used. Moreover, when the error term is assumed to follow a skewed distribution, larger discrepancies are found throughout. I find a similar pattern in simulations, in which I assess how different methods perform with respect to the true parameters of interest, rather than to each other.

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43

Cosma, Ioana Ada. "Dimension reduction of streaming data via random projections." Thesis, University of Oxford, 2009. http://ora.ox.ac.uk/objects/uuid:09eafd84-8cb3-4e54-8daf-18db7832bcfc.

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A data stream is a transiently observed sequence of data elements that arrive unordered, with repetitions, and at very high rate of transmission. Examples include Internet traffic data, networks of banking and credit transactions, and radar derived meteorological data. Computer science and engineering communities have developed randomised, probabilistic algorithms to estimate statistics of interest over streaming data on the fly, with small computational complexity and storage requirements, by constructing low dimensional representations of the stream known as data sketches. This thesis combines techniques of statistical inference with algorithmic approaches, such as hashing and random projections, to derive efficient estimators for cardinality, l_{alpha} distance and quasi-distance, and entropy over streaming data. I demonstrate an unexpected connection between two approaches to cardinality estimation that involve indirect record keeping: the first using pseudo-random variates and storing selected order statistics, and the second using random projections. I show that l_{alpha} distances and quasi-distances between data streams, and entropy, can be recovered from random projections that exploit properties of alpha-stable distributions with full statistical efficiency. This is achieved by the method of L-estimation in a single-pass algorithm with modest computational requirements. The proposed estimators have good small sample performance, improved by the methods of trimming and winsorising; in other words, the value of these summary statistics can be approximated with high accuracy from data sketches of low dimension. Finally, I consider the problem of convergence assessment of Markov Chain Monte Carlo methods for simulating from complex, high dimensional, discrete distributions. I argue that online, fast, and efficient computation of summary statistics such as cardinality, entropy, and l_{alpha} distances may be a useful qualitative tool for detecting lack of convergence, and illustrate this with simulations of the posterior distribution of a decomposable Gaussian graphical model via the Metropolis-Hastings algorithm.

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44

Sgueo, Carrie E. "Seasonal Acclimatization Through Physiological Changes in Northern Cardinals (Cardinalis cardinalis)." Miami University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=miami1250100103.

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45

Villela, Pedro Ferraz 1982. "Um algoritmo exato para a otimização de carteiras de investimento com restrições de cardinalidade." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307123.

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Orientador: Francisco de Assis Magalhães Gomes Neto
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
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Resumo: Neste trabalho, propomos um método exato para a resolução de problemas de programação quadrática que envolvem restrições de cardinalidade. Como aplicação, empregamos o método para a obtenção da fronteira eficiente de um problema (bi-objetivo) de otimização de carteiras de investimento. Nosso algoritmo é baseado no método Branch-and-Bound. A chave de seu sucesso, entretanto, reside no uso do método de Lemke, que é aplicado para a resolução dos subproblemas associados aos nós da árvore gerada pelo Branch-and-Bound. Ao longo do texto, algumas heurísticas também são introduzidas, com o propósito de acelerar a convergência do método. Os resultados computacionais obtidos comprovam que o algoritmo proposto é eficiente.
Abstract: In this work, we propose an exact method for the resolution of quadratic programming problems involving cardinality restrictions. As an application, the algorithm is used to generate the effective Pareto frontier of a (bi-objective) portfolio optimization problem. This algorithm is based on the Branch-and-Bound method. The key to its success, however, resides in the application of Lemke's method to the resolution of the subproblems associated to the nodes of the tree generated by the Branch-and-Bound algorithm. Throughout the text, some heuristics are also introduced as a way to accelerate the performance of the method. The computational results acquired show that the proposed algorithm is efficient.
Mestrado
Otimização
Mestre em Matemática Aplicada

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46

Rix, James Gregory. "Hypercube coloring and the structure of binary codes." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2809.

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A coloring of a graph is an assignment of colors to its vertices so that no two adjacent vertices are given the same color. The chromatic number of a graph is the least number of colors needed to color all of its vertices. Graph coloring problems can be applied to many real world applications, such as scheduling and register allocation. Computationally, the decision problem of whether a general graph is m-colorable is NP-complete for m ≥ 3. The graph studied in this thesis is a well-known combinatorial object, the k-dimensional hypercube, Qk. The hypercube itself is 2-colorable for all k; however, coloring the square of the cube is a much more interesting problem. This is the graph in which the vertices are binary vectors of length k, and two vertices are adjacent if and only if the Hamming distance between the two vectors is at most 2. Any color class in a coloring of Q2k is a binary (k;M, 3) code. This thesis will begin with an introduction to binary codes and their structure. One of the most fundamental combinatorial problems is finding optimal binary codes, that is, binary codes with the maximum cardinality satisfying a specified length and minimum distance. Many upper and lower bounds have been produced, and we will analyze and apply several of these. This leads to many interesting results about the chromatic number of the square of the cube. The smallest k for which the chromatic number of Q2k is unknown is k = 8; however, it can be determined that this value is either 13 or 14. Computational approaches to determine the chromatic number of Q28 were performed. We were unable to determine whether 13 or 14 is the true value; however, much valuable insight was learned about the structure of this graph and the computational difficulty that lies within. Since a 13-coloring of Q28 must have between 9 and 12 color classes being (8; 20; 3) binary codes, this led to a thorough investigation of the structure of such binary codes.

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47

Moraes, Júnior Rogério Jacinto de. "Enumerabilidade e Não Enumerabilidade de conjuntos: uma abordagem para o Ensino Básico." Universidade Federal do Amazonas, 2015. http://tede.ufam.edu.br/handle/tede/4601.

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CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
In this dissertation we discuss briefly some issues quickly treated during the undergraduate course such as countable and uncountable sets, cardinality and other related subjects. We will present a brief historical review of the facts that gave rise to these problems, as well as people who have developed knowledge on these issues. The purpose of this report is succinctly present a direction to the Basic Education teachers for their classes, giving the opportunity to teachers to have more confidence when working with numerical sets and functions on these sets. It will also be used as a motivational element to the theoretical approach, or this associated with the problems that gave rise to such issues, both for teachers, and for students and scholars interested, because these are curious and intriguing subjects for those which enjoy studying mathematics of such subjects that are, of some kind, advanced or abstract. Among others, we can assign the comparison of cardinality of infinite sets, demonstrating that sets of racional numbers and the algebraic numbers are countable, and the real numbers and the transcendental numbers are uncountable, and besides, we show the cardinality of other interesting sets that are of great value to research in modern mathematics. Thus we think we are contributing to the improvement of teachers and students of Basic Education.
Neste trabalho abordaremos alguns assuntos tratados brevemente durante o curso de graduação tais como enumerabilidade e não enumerabilidade de conjuntos, cardinalidade e outros assuntos correlatos. Apresentaremos um pequeno aparato histórico que deram origem a esses problemas, assim como as pessoas que lançaram conhecimento sobre tais temas. O objetivo é apresentar sucintamente aos professores do ensino básico suporte para as aulas, dando a oportunidade do professor ter mais segurança quando trabalhar com conjuntos numéricos. Também servirá como elemento motivacional tanto para professores como para os alunos interessados, pois trata de assuntos curiosos e atiçadores para quem gosta de estudar matemática, como comparar a cardinalidade de conjuntos infinitos, a infinidade de números transcendentes e sua dificuldade de determiná-los e outros assuntos que são de grande riqueza de pesquisa na matemática moderna. Dessa forma pensamos estar contribuindo para o aperfeiçoamento de professores e alunos do ensino básico.

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48

Sibilano, Marialisa. "Numeri ordinali e cardinali." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amslaurea.unibo.it/1269/.

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Leston, Lionel. "Are urban forests ecological traps for understory birds? An examination with Northern Cardinals (Cardinalis Cardinalis)." The Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=osu1407239353.

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50

Fouquet, Mireille. "Anneau d'endomorphismes et cardinalité des courbes elliptiques : aspects algorithmiques." Palaiseau, Ecole polytechnique, 2001. http://www.theses.fr/2001EPXX0051.

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Dissertations / Theses on the topic 'Cardinality'

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