O polietileno linear de baixa densidade (LLDPE) com comonômeros 1-buteno e 1-octeno apresenta fácil processabilidade e baixo custo. Por outro lado, as poliolefinas em geral possuem baixa reatividade, dificultando a adesão com outros substratos e limitando suas aplicações. Por esta razão tratamentos foram desenvolvidos para minimizar essa característica, sendo conhecidos como processos de enxertia ou funcionalização. Este trabalho teve por finalidade avaliar a influência do tamanho dos comonômeros buteno e octeno e dos dois tipos de agentes funcionalizantes anidrido maléico (AM) e anidrido tetrahidroftálico (ATF) no processo de funcionalização via úmida das poliolefinas. Para se avaliar a significância estatística de quatro variáveis dos experimentos: porcentagem do agente funcionalizante (AM ou ATF), porcentagem do iniciador peróxido de benzoíla (BPO), tipo de comonômero (buteno e octeno) e o tempo de reação, usou-se as ferramentas estatísticas conhecidas como planejamento fatorial fracionário e planejamento fatorial composto central. O grau de funcionalização das poliolefinas modificadas foi determinado por espectroscopia vibracional no infravermelho (IR). Os efeitos do grau de funcionalização e do tipo de anidrido sobre o grau de cristalinidade das amostras foram obtidos por difração de raios-X e calorimetria exploratória diferencial (DSC). A molhabilidade das poliolefinas foi determinada, antes e depois da funcionalização, por medidas de ângulo de contato, utilizando-se gotas de água como líquido. Observamos que (1) a funcionalização das poliolefinas modificadas com AM se mostrou mais eficiente do que com ATF, porque as moléculas de ATF são mais reativas, o que as torna mais suscetíveis a reações paralelas como a homopolimerização e/ou reticulação; (2) a modificação das poliolefinas com AM apresentou significância estatística só nas variáveis: porcentagem de BPO e porcentagem de AM; (3) as, poliolefinas modificadas com ATF apresentaram duas variáveis significativas, o tempo da reação e a interação existente entre o tempo de reação e a porcentagem de ATF; (4) as poliolefinas modificadas com AM e ATF apresentaram uma redução na temperatura de fusão de até 3,3°C e 4,3°C respectivamente, evidenciando alterações na estrutura cristalina do polímero; (5) ensaios de difração de raios-X corroboram com os valores obtidos por calorimetria exploratória diferencial (DSC), uma vez que não ocorreu deslocamento dos máximos de difração e tampouco do halo amorfo; mas houve uma diminuição acentuada nos picos de difração (diminuição da altura e aumento da largura), reflexo da desestruturação causada pelo agente funcionalizante nos domínios cristalinos; (6) observou-se que o aumento no GF promoveu uma maior molhabilidade da superfície, indicando uma maior interação dos grupos polares enxertados com a água. Os valores altos de Li8 indicam alta rugosidade e ou heterogeneidade química da superfície; (7) não houve variação significativa no grau de funcionalização quando utilizado poliolefinas com diferentes comonômeros; (8) o aumento na concentração de poliolefina promove uma maior funcionalização. (9) o método de funcionalização desenvolvido levou à reticulação mínima da poliolefinas. / Linear low-density polyethylene with comonomer 1-butene and 1-octene presents the advantages of easy processing and low cost. On the other hand, polyolefins are inert materials with very low surface energy, impeaching the adhesion to other materials. In order to improve the adhesion to other materials, grafting or functionalization processes have been developed. This work evaluates the influence of the comonomers butene and octene and of two types of anhydride, maleic anhydride (MA) and tetrahydrophthalic anhydride (THA), on the functionalization of polyolefins by means of chemical reactions in solution. In order to evaluate the statistic meaning of four variables (content of anhydride, content of benzoyl peroxide, type of comonomer, and time of reaction) in the functionalization process the fractional factorial design and the central composite experimental design were used. The degree of functionalization (DF) was determined by means of infrared spectroscopy (IR). The effects of (DF) and of the type of anhydride on the crystallinity of the modified samples were obtained from X-ray diffraction and differential scanning calorimetry (DSC). The wettability of polyolefins was determinated before and after of the functionalization by means of contact angle measurements using water drops like liquid. We observe that ( 1) the functionalization of polyolefins modified with MA are more efficient than the polyolefins modified with THA because the THA molecules are more reactive than the MA molecules, favoring side reactions as homopolymerization and cross-linking; (2) the modification of the polyolefins with MA shows statistic meaning only in the following variables: contents of BPO and MA percentage; (3) the polyolefins modified with THA show significative variables: the time of reaction and the interaction between the time of reaction and the THA content; (4) the polyolefins modified with MA and THA show a reduction in the melt temperature of 3,3°C and 4,3°C respectively, indicating changes in the crystalline structure of polymer; (5) X-ray diffractograms confirmed the results obtained by differential scanning calorimetry (DSC), since the diffraction peaks turned smaller; (6) the increase in the DF improved the surface wettability; (7) the size of comonomer has no influence on the DF; (8) the DF depends on the polyolefin concentration; (9) the polyolefins modification by chemical reactions in solution presented very low cross-linking degree.

"Software Engineering represents a structured, disciplined approach to the design and implementation of software systems. Adhering to such an approach enables greater planning for and management of systemic complexity. By augmenting the process to emphasize desired features that are to be present in the final software system, we can ensure that the final system will be modular, extensible, and testable with respect to individual features. Moreover, an existing system can be characterized according to its features and refactored in the same way. This thesis investigates feature-oriented augmentation to the standard software engineering approach. We employ logic-based feature models to characterize the features in the product family of an existing system. We use the characterized features to refactor a case study to reflect the approach using aspects. We demonstrate using the AspectJ Eclipse plugin how to publish different frameworks in a framework product line. Our results show that the refactoring efforts produce a modular, extensible, and testable system in which individual behavioral features selected from a product family of features can be added to or subtracted from the system with ease."

Thesis (M.ED.) --University of Limpopo, 2009. / This study focuses on the morpheme le in Northern Sotho. It is sometimes confusing to establish the correct semantic function which the morpheme le expresses; and also to classify it into a certain word category. This study suggests the morphological features which the morpheme le bears in terms of its word categorization. The morpheme le in Northern Sotho can be used as a conjunction, a demonstrative pronoun, an agreement, a preposition, a copulative, an adverb and a complement as well. It is suggested in this study, ways of identifying the semantic function of the morpheme le in various contexts. This study reflects that the morpheme le in Northern Sotho can be used to denote: possession, accompaniment, location, additive focus, existentialism and honorifics.

<p>The purpose of the study is, through literature and interview studies, to analyze and draw attention to critical mindedness regarding news features in a multilateral way. In the interview 16 participants got to see three SVT news features with lack of criticism. Great importance was given to the spontaneous reasoning of the participant. The study is explorative and has given a number of hypotheses and ideas for further research concerning the subject. Among other things the study shows that previous beliefs affect the critical mindedness of the individual, that individuals have the ability to think critically if reminded and that the trust of the source and medium affects the critical mindedness of the individual.</p>

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In this dissertation, I introduce a general, flexible framework for learning direct mappings from images to actions in an agent that interacts with its surrounding environment. This work is motivated by the paradigm of purposive vision. The original contributions consist in the design of reinforcement learning algorithms that are applicable to visual spaces. Inspired by the paradigm of local-appearance vision, these algorithms exploit specialized visual features that can be detected in the visual signal. Two different ways to use the visual features are described. Firstly, I introduce adaptive-resolution methods for discretizing the visual space into a manageable number of perceptual classes. To this end, a percept classifier that tests the presence or absence of few highly informative visual features is incrementally refined. New discriminant visual features are selected in a sequence of attempts to remove perceptual aliasing. Any standard reinforcement learning algorithm can then be used to extract an optimal visual control policy. The resulting algorithm is called "Reinforcement Learning of Visual Classes." Secondly, I propose to exploit the raw content of the visual features, without ever considering an equivalence relation on the visual feature space. Technically, feature regression models that associate visual features with a real-valued utility are introduced within the Approximate Policy Iteration architecture. This is done by means of a general, abstract version of Approximate Policy Iteration. This results in the "Visual Approximate Policy Iteration" algorithm. Another major contribution of this dissertation is the design of adaptive-resolution techniques that can be applied to complex, high-dimensional and/or continuous action spaces, simultaneously to visual spaces. The "Reinforcement Learning of Joint Classes" algorithm produces a non-uniform discretization of the joint space of percepts and actions. This is a brand new, general approach to adaptive-resolution methods in reinforcement learning that can deal with arbitrary, hybrid state-action spaces. Throughout this dissertation, emphasis is also put on the design of general algorithms that can be used in non-visual (e.g. continuous) perceptual spaces. The applicability of the proposed algorithms is demonstrated by solving several visual navigation tasks.

The purpose of the study is, through literature and interview studies, to analyze and draw attention to critical mindedness regarding news features in a multilateral way. In the interview 16 participants got to see three SVT news features with lack of criticism. Great importance was given to the spontaneous reasoning of the participant. The study is explorative and has given a number of hypotheses and ideas for further research concerning the subject. Among other things the study shows that previous beliefs affect the critical mindedness of the individual, that individuals have the ability to think critically if reminded and that the trust of the source and medium affects the critical mindedness of the individual.

Proteins are the structural components of living cells and tissues, and thus an important building block in all living organisms. Patterns in proteins sequences are some subsequences which appear frequently. Patterns often denote important functional regions in proteins and can be used to characterize a protein family or discover the function of proteins. Moreover, it provides valuable information about the evolution of species. Grouping protein sequences that share similar structure helps in identifying sequences with similar functionality. Many algorithms have been proposed for clustering proteins according to their similarity, i.e., sequential patterns in protein databases, for example, feature-based clustering algorithms of the global approach and the local approach. They use the algorithm of mining sequential patterns to solve the no-gap-limit sequential pattern problem in a protein sequences database, and then find global features and local features separately for clustering. Feature-based clustering algorithms are entirely different approaches to protein clustering that do not require an all-against-all analysis and use a near-linear complexity K-means based clustering algorithm. Although feature-based clustering algorithms are scalable and lead to reasonably good clusters, they consume time on performing the global approach and the local approach separately. Therefore, in this thesis, we propose hybrid algorithms to find and mark features for feature-based clustering algorithms. We observe an interesting result from the relation between the local features and the closed frequent sequential patterns. The important observation which we find is that some features in the closed frequent sequential patterns can be taken apart to several features in the local selected features and the total support number of these features in the local selected features is equal to the support number of the corresponding feature in the closed frequent sequential patterns. There are two phases, find-feature and mark-feature, in the global approach and the local approach after mining sequential patterns. In our hybrid algorithms of Method 1 (LocalG), we first find and mark the local features. Then, we find the global features. Finally, we mark the bit vectors of the global features efficiently from the bit vector of the local features. In our hybrid algorithms of Method 2 (CLoseLG), we first find the closed frequent sequential patterns directly. Next, we find local candidate features efficiently from the closed frequent sequential patterns and then mark the local features. Finally, we find and mark the global features. From our performance study based on the biological data and the synthetic data, we show that our proposed hybrid algorithms are more efficient than the feature-based algorithm.

Promoter classification is the task of separating promoter from non promoter sequences. Determining promoter regions where the transcription initiation takes place is important for several reasons such as improving genome annotation and defining transcription start sites. In this study, various promoter prediction methods called ProK-means, ProSVM, and 3S1C are proposed. In ProSVM and ProK-means algorithms, structural features of DNA sequences are used to distinguish promoters from non promoters. Obtained results are compared with ProSOM which is an existing promoter prediction method. It is shown that ProSVM is able to achieve greater recall rate compared to ProSOM results. Another promoter prediction methods proposed in this study is 3S1C. The difference of the proposed technique from existing methods is using signal, similarity, structure, and context features of DNA sequences in an integrated way and a hierarchical manner. In addition to current methods related to promoter classification, the similarity feature, which compares the promoter regions between human and other species, is added to the proposed system. We show that the similarity feature improves the accuracy. To classify core promoter regions, firstly, signal, similarity, structure, and context features are extracted and then, these features are classified separately by using Support Vector Machines. Finally, output predictions are combined using multilayer perceptron. The result of 3S1C algorithm is very promising.

This study investigates the role of perceptual distinctiveness in consonant inventories. While distinctiveness appears to play a role in the shaping of vowel systems, a literature review indicates that its status in consonant selections remains unclear. To address this issue I used speech materials recorded by a trained phonetician containing 35 CV syllables with seven places of articulation (bilabial, dental, alveolar, retroflex, palatal, velar and uvular) and five vowels: [i] [[epsilon]] [a] [[backwards c]] and [u]. Detailed acoustic measurements were performed: formant patterns at vowel onsets (loci) and vowel midpoints, transitions rates and burst spectra. To validate the speech material, comparisons were made with published data and with formant frequencies derived by means of an articulatory model. Perceptual data were collected on these 35 syllables. Multiple Regression analyses were performed with the coded dissimilarities as the dependent variable and with (combinations of) formant-based distances, time constant differences and burst differences as the independent variables. The results indicated that acoustic measurements could be successfully used to help explain listener responses. Optimal place sets were obtained from a rank ordering of the CV syllables with respect to 'individual salience' (defined as the sum of a syllable's perceptual distance to other places in the same vowel context) and from a replication of the Liljencrants & Lindblom systemic criterion of maximizing distances within all vowel pairs. Instead of the typologically prevalent pattern of [b d g], predictions were found to be vowel-dependent and to often favor CV:s located at the 'corners' of the acoustic F3-F2 space, viz., uvular, palatal and retroflex. This finding leads to a conclusion that distinctiveness alone is unlikely to account for how languages use place of articulation in voiced stops. For more successful attempts, future work should be directed towards defining and incorporating production constraints such as 'ease of articulation'.