Submitted by Marcos Grilo Rosa (grilo@uefs.br) on 2017-01-05T19:11:59Z No. of bitstreams: 1 tesevsfinalMarcosGrilo.pdf: 11311408 bytes, checksum: 3ce07aff3fe0fb9dc534e80e667eeb5b (MD5) / Rejected by Maria Auxiliadora da Silva Lopes (silopes@ufba.br), reason: Prezado Marcos, Favor registrar os nomes completos dos participantes da banca; inserir o "abstract" e as "key words". Saudações, Maria Auxiliadora Lopes UFBA/Faced/Biblioteca on 2017-01-09T14:10:18Z (GMT) / Submitted by Marcos Grilo Rosa (grilo@uefs.br) on 2017-01-09T17:16:07Z No. of bitstreams: 1 tesevsfinalMarcosGrilo.pdf: 11311408 bytes, checksum: 3ce07aff3fe0fb9dc534e80e667eeb5b (MD5) / Approved for entry into archive by Maria Auxiliadora da Silva Lopes (silopes@ufba.br) on 2017-01-19T14:35:53Z (GMT) No. of bitstreams: 1 tesevsfinalMarcosGrilo.pdf: 11311408 bytes, checksum: 3ce07aff3fe0fb9dc534e80e667eeb5b (MD5) / Made available in DSpace on 2017-01-19T14:35:53Z (GMT). No. of bitstreams: 1 tesevsfinalMarcosGrilo.pdf: 11311408 bytes, checksum: 3ce07aff3fe0fb9dc534e80e667eeb5b (MD5) / No campo da inteligência artificial, redes semânticas são utilizadas para a representação de conhecimento e processamento de linguagem natural. Redes semânticas são sistemas de representação do conhecimento baseados em grafos cujos vértices são palavras e as arestas, os relacionamentos entre as palavras estabelecidos por alguma regra. Lidar com redes semânticas é uma atividade bastante complicada, principalmente, quando se manipula redes com milhares de palavras. Conjecturamos a possibilidade de se representar uma dada rede semântica baseada em títulos de artigos de periódicos científicos (RST) por meio de uma RST uniforme, de modo que esta possua a mesma estrutura topológica e reflita o vocabulário da RST original. O problema da nossa tese consiste em saber qual o menor tamanho de uma RST uniforme que pode ser obtida de uma dada RST. Esta pesquisa visa determinar o ponto crítico no qual ocorre uma mudança topológica de uma RST de modo que a rede obtida reflita o vocabulário da RST original. Realizamos um experimento que consistiu em submeter RST a estratégias de remoção de vértices. Os resultados apontam a existência de uma fração fp de vértices removidos aleatoriamente e uniformemente que mantém a estrutura topológica e reflita o vocabulário da RST original. Desta forma, RST podem ser representadas por RST uniformes mínimas. A representação do conhecimento é determinante em processos e cientes de busca de informações e difusão de conhecimento. Ademais, RST uniformes mínimas poderão auxiliar pesquisadores na busca mais e ciente de temas relacionados ao seu objeto de investigação. / Abstract In the field of artificial intelligence, semantic networks are used for knowledge representation and natural language processing. Semantic networks are graph-based knowledge representation systems whose vertices are words and edges, relationships between words set by a rule. Dealing with semantic networks is a very complicated activity, mainly, when it handles networks with thousands of words. We conjecture the possibility of representing a given semantic network based on titles of scientific papers (RST) by a uniform RST, so that this has the same topological structure and reflect the vocabulary of the original RST. The problem of our thesis is to know what a uniform smaller RST can be obtained from a given RST. This study aims to determine the critical point at which there is a topological change of a RST so that the network obtained reflect the vocabulary of the original RST. We conducted an experiment that it consists to submit RST removing vertices strategies. The results indicate the existence of a fraction fp vertices removed randomly and evenly preserving the topological structure and reflect the vocabulary of the original RST. Thus, RST may be represented by minimum uniform RST. The representation of knowledge is determinant in efficient processes search of information and diffusion of knowledge. In addition, minimum uniform RST can assist researchers in the most efficient search issues related to its investigation.

The topic of Markov Random Fields (MRFs) has been well studied in the past, and has found practical use in various image processing, and machine learning applications. Where coding is concerned, MRF specific schemes have been largely unexplored. In this thesis, an overview is given of recent developments and challenges in the lossless coding of MRFs. Specifically, we concentrate on difficulties caused by computational intractability due to the partition function of the MRF. One proposed solution to this problem is to segment the MRF with a cutset, and encode the components separately. Using this method, arithmetic coding is possible via the Belief Propagation (BP) algorithm. We consider two cases of the BP algorithm: MRFs with only simple cliques, and MRFs with complex cliques. In the latter case, we study a minimum radius condition requirement for ensuring that all cliques are accounted for during coding. This condition also simplifies the process of conditioning on observed sites. Finally, using these results, we develop a systematic procedure of clustering and choosing cutsets. / Thesis (Master, Mathematics & Statistics) -- Queen's University, 2013-08-12 14:50:00.596

As children enter adolescence, social status within the peer hierarchy gains importance. Variable-oriented research has linked adolescent popularity with both positive and negative adjustment outcomes. Popularity may be better understood with reference to types or subgroups of similar individuals, identified through person-oriented approaches. Resource Control Theory (RCT: Hawley, 1999) posits three distinct types of popular adolescents: coercive, prosocial, and bistrategic. The existence and adjustment correlates of the prosocial and coercive groups have been well-established, but little evidence supports the existence of a bistrategic popular group of adolescents, and even less is known about their adjustment correlates. The present study aims to confirm the existence of the popularity groups hypothesized by RCT and to identify group differences in social adjustment and problem behaviors. A sample of 568 adolescents (n = 288 girls, 280 boys; M age = 12.50) completed peer nomination procedures and self-report questionnaires in the Fall and Spring of the 7th and 8th grades. Longitudinal latent profile analyses classified adolescents into profile groups on the basis of initial physical aggression, relational aggression, and prosocial behavior, and four time points of popularity spanning the 7th and 8th grades. Repeated measures ANOVAs examined profile group differences in social adjustment (peer acceptance, peer rejection, physical victimization, relational victimization, and preference for solitude) and problem behaviors (disruptiveness and delinquency) across the 7th and 8th grades. Results indicate that adolescents fall into one of four distinct groups: aggressive popular, prosocial popular, bistrategic popular, and average. Bistrategic popular adolescents evinced positive social adjustment, exhibiting the highest levels of popularity and peer acceptance and the lowest levels of peer rejection, victimization, and preference for solitude. Despite their social skill advantages, bistrategic popular adolescents were also at risk for problem behaviors. Bistrategic popular adolescents scored above average on problem behaviors, including physical and relational aggression, disruptiveness, and delinquency. Bistrategic popular adolescents successfully navigate the social world in a manner that both offers hope for positive long-term adjustment and concern for the same. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection

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Taiwan area has administered local autonomy for over fifty years. At first its authority was mainly based on an administrative order called the Guidelines for Local Autonomy and then the Local System Law at present. Among the powers vested by the law, veto is an important weapon for the local administration to balance legislative power. However, the veto power has yet to be further elaborated for it was used in just a little more than 500 cases all over Taiwan area in the past sixty years. This essay tries to probe both the theoretical and practical facets of the veto system. The local system of this country adopted an administration and legislature separation system. In case a conflict should occur between the two powers, its time for veto to help solve the dilemma. As a matter of fact, government is responsible for proposing important bills, the officials can defend its policies while attending the legislature for interpellation or proposal deliberation. In addition, budgets are only proposed by local administrations. Local legislatures are restrained from increasing the sizes of the proposed budgets by law. So while deliberating on draft resolutions, the legislature would consider officials¡¦ opinions and not to make less feasible resolutions. Despite an unfeasible resolution should be made, the administration would rather seek other ways out than veto it in order to maintain the harmony between the two powers. More over, the content of the Local System Law has put more weight on administration power so as to make the legislature conservative in enforcing its power lest its resolutions should be vetoed. In recent years, democracy has enrooted into the daily lives of the society; Local political environment change drastically and divided government is now a commonplace; Local cliques have either reformed or vanished; Gangsters and money politics enter local legislatures and struggle for personal interests. The administrations are facing an overwhelmingly new eco system in local legislatures. Comparing the factors that induce a veto, it is found that the conflict for personal interest is the most common cause. The veto system is a mechanism of instrument equilibrium. Administration and legislation should stand on an equal position to discuss veto dispute to reach the purposes of the separation of powers between the executive and legislature. This essay suggests the central government that the time limit, quorum, scope and method in deliberating a veto should be explicitly defined in law so as to make sure a healthier veto system.

Principal Components Analysis is a standard tool in data analysis, widely used in data-rich fields such as computer vision, data mining, bioinformatics, and econometrics. For a set of vectors in n dimensions and a natural number k less than n, the method returns a subspace of dimension k whose average squared distance to that set is as small as possible. Besides saving computation by reducing the dimension, projecting to this subspace can often reveal structure that was hidden in high dimension. This thesis considers several novel extensions of PCA, which provably reveals hidden structure where standard PCA fails to do so. First, we consider Robust PCA, which prevents a few points, possibly corrupted by an adversary, from having a large effect on the analysis. When applied to learning noisy logconcave mixture models, the algorithm requires only slightly more separation between component means than is required for the noiseless case. Second, we consider Isotropic PCA, which can go beyond the first two moments in identifying ``interesting' directions in data. The method leads to the first affine-invariant algorithm that can provably learn mixtures of Gaussians in high dimensions, improving significantly on known results. Thirdly, we define the ``Subgraph Parity Tensor' of order r of a graph and reduce the problem of finding planted cliques in random graphs to the problem of finding the top principal component of this tensor.

[pt] O problema de particionamento de grafos em cliques ocorre freqüentemente em diversas áreas tais como Ciências sociais, Ciências Econômicas, Biologia, Análise de Agrupamentos e em todas as áreas onde é necessário a classificação de elementos. Estuda-se aqui os principais algoritmos exatos e as principais heurísticas que constam na literatura. É feita uma análise do desempenho das heurísticas no pior caso e apresenta-se uma classe especial de problemas para os quais o seu desempenho é arbitrariamente ruim. Apresentam-se quatro novas heurísticas para o problema, duas delas baseadas nos métodos conhecidos por simulated anneling e por tabu search. Elas são comparadas entre si através da análise dos resultados de suas aplicações a problemas-teste, a problemas que ocorre na realidade e a classe de problemas especiais mencionada acima. / [en] The clique partitioning problem arise very often in many fields as Social Science, Economics, Biology, Cluster analysis and in all other fields that need a classification of elements. The main exact algorithms and heuristics that appear in the literature are studied. A especial class of instances of the clique partitioning problem for which the most comonly used heuristics perform arbitrarily bad is exhibited. Four new heuristics are presented and two of them are based on the known simulated anneling and tabu search methods. They are analised by their application to test-problems, real-life-problems and to the special class of instances mentioned above

No description available.

La détection de potentielles cibles secondaires ou off-targets d’un ligand donné requiert la détermination de son site d’interaction et la recherche de sites d’interaction similaires sur d’autres protéines. Dans le but de mener à bien cette étude, nous avons développé PatchSearch : cet outil compare un patch requête, correspondant à un site d’interaction, avec la surface d’une cible potentielle. L’algorithme employé s’appuie sur une méthode originale de recherche de quasi-cliques dans un graphe produit : cette approche identifie des groupes d’atomes du patch appariés avec ceux de la surface ciblée avec des propriétés physico-chimiques conservées et dans des configurations proches. Nous montrons que PatchSearch trouve des patches qui correspondent à ceux qui sont connus sur les surfaces ciblées. De plus, les résultats de l’application de PatchSearch sur des protéines flexibles indiquent que l’approche des quasi-cliques permet de retrouver à la fois les parties rigides et flexibles des patches,contrairement à la recherche classique de cliques. Enfin, les performances de Patch-Search sont équivalentes à celles des autres outils de comparaison de sites de liaison.Nous avons également appliqué PatchSearch sur des off-targets de médicaments impliqués dans le traitement de cancers. Nos expériences suggèrent l’utilisation de PatchSearch dans la recherche des éventuelles off-targets d’un médicament. / Detection of putative off-targets for a ligand requires to search for some similarbinding sites onto other proteins surface. In order to achieve this goal, we developeda tool named PatchSearch. This program compares a query patch, whichcontains the binding site, with the surface a potentially targeted protein. Patch-Search’s algorithm is based on an original method searching for some quasi-cliquesin a graph product, which identifies some atoms both in the patch and in the surfacewith conserved physicochemical properties and in similar configurations. Weshow that PatchSearch efficiently finds known patches on protein surfaces. Moreover,application of PatchSearch on flexible proteins shows that, unlike the classiccliques approach, quasi-cliques method allows to find both rigid and flexible partsof the patches. PatchSearch gets similar results compared to the other binding sitecomparison tools. We also applied PatchSearch to find patches binding polypharmacologicaldrugs involved in cancer treatment, in order to identify them on knownoff targets. Our experiments suggest to employ PatchSearch in off-targets detectionprocess.

No description available.