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Productivity and safety concerns of traditional cable harvesting systems have been the key drivers for increasing levels of mechanisation in New Zealand. The use of grapples in cable yarding could eliminate the need for motor-manual tree fallers and breaker-outs in most situations. A comparative time study was carried out on two mechanised cable harvesting systems utilising grapple carriages in an attempt to better understand the benefits and limitations of each system in different harvest settings. These systems include the Mechanical system which involved a swing yarder operating a mechanical grapple carriage and the Motorised system, which used a tower yarder with a motorised grapple carriage. The Mechanical system took less time to accumulate felled trees but took longer to unhook trees on the landing than the Motorised system. The Mechanical system had a shorter cycle time (2.07 minutes) than the Motorised system (2.32 minutes) and extracted 1.3 tonnes more than the Motorised system per cycle. The Motorised system had shorter cycle times when in horizontal haul distances of less than 90 metres, but had the longest times when the distance exceeded this. Utilisation rates were similar between the two systems, although the main difference in delays between the two systems was the use of surgepiles on the landing by the Motorised system. Both systems were effective, although on average the Mechanical system was more productive, with a productivity of 45 t/SMH, compared to 40 t/SMH for the Motorised system. The Mechanical system was the most productive when extracting mechanically felled and pre-bunched or trees while the Motorised system was the most productive when extracting motor-manually felled trees. Pre-bunching with an excavator was a more cost effective method than handing stems directly to the grapple carriage. Further research of the Mechanical system under more adverse conditions would allow a better overall comparison.

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.

This thesis focuses on the engineering of algorithms for massive data sets. In recent years, massive data sets have become ubiquitous and existing computing applications, for the most part, cannot handle these data sets efficiently: either they crash or their performance degrades to a point where they take unacceptably long to process the input. Parallel computing and I/O-efficient algorithms provide the means to process massive amounts of data efficiently. The work presented in this thesis makes use of these techniques and focuses on obtaining practically efficient solutions for specific problems in computational geometry and graph theory. We focus our attention first on skyline computations. This problem arises in decision-making applications and has been well studied in computational geometry and also by the database community in recent years. Most of the previous work on this problem has focused on sequential computations using a single processor, and the algorithms produced are not able to efficiently process data sets beyond the capacity of main memory. Such massive data sets are becoming more common; thus, parallelizing the skyline computation and eliminating the I/O bottleneck in large-scale computations is increasingly important in order to retrieve the results in a reasonable amount of time. Furthermore, we address two fundamental problems of graph analysis that appear in many application areas and which have eluded efforts to develop theoretically I/O-efficient solutions: computing the strongly connected components of a directed graph and topological sorting of a directed acyclic graph. To approach these problems, we designed algorithms, developed efficient implementations and, using extensive experiments, verified that they perform well in practice. Our solutions are based on well understood algorithmic techniques. The experiments show that, even though some of these techniques do not lead to provably efficient algorithms, they do lead to practically efficient heuristic solutions. In particular, our parallel algorithm for skyline computation is based on divide-and-conquer, while the strong connectivity and topological sorting algorithms use techniques such as graph contraction, the Euler technique, list ranking, and time-forward processing.

In this dissertation, we present a novel foundational framework that lays out a theoretical underpinning for the emerging services science. The proposed framework provides disciplined and systematic support for efficient access to Web services' functionalities. The key components of the proposed framework centers around a novel service model that provides a formal abstraction of the Web services within an application domain. A service calculus and a service algebra are defined to facilitate users in accessing services via declarative service queries. We provide the implementation of the service algebra. This enables the generation of Service Execution Plans (SEPs) that can be used by users to directly access services. We present an optimization algorithm to efficiently select the SEPs with the best QoWS. We then propose a multi-objective optimization approach that releases users from the tedious weight assigning process. We develop service skyline computation techniques that return a set of most interesting SEPs. The service skyline guarantees to include the user desired SEPs. We further explore a set of novel heuristics for computing service skylines over sets of services. This enables users to efficiently and optimally access multiple services simultaneously as an integrated service package. Finally, we consider the performance fluctuation of service providers due to the dynamic service environment. We propose an uncertain QoWS model and a novel concept called p-dominant service skyline. We develop new indexing structures and algorithms to efficiently compute the p-dominant service skyline. We derive analytical models and conduct extensive sets of experiments to evaluate the proposed framework and service query optimization algorithms. / Ph. D.

De nos jours, nous assistons à l’émigration du Web de données vers le Web orienté services. L’amélioration des capacités et fonctionnalités des moteurs actuels de recherche sur le Web, par des techniques efficaces de recherche et de sélection de services, devient de plus en plus importante. Dans cette thèse, dans un premier temps, nous proposons un cadre de composition de services Web en tenant compte des préférences utilisateurs. Le modèle fondé sur la théorie des ensembles flous est utilisé pour représenter les préférences. L’approche proposée est basée sur une version étendue du principe d’optimalité de Pareto. Ainsi, la notion des top-k compositions est introduite pour répondre à des requêtes utilisateurs de nature complexe. Afin d’améliorer la qualité de l’ensemble des compositions retournées, un second filtre est appliqué à cet ensemble en utilisant le critère de diversité. Dans un second temps, nous avons considéré le problème de la sélection des services Web en présence de préférences émanant de plusieurs utilisateurs. Une nouvelle variante, appelée Skyline de services à majorité, du Skyline de services traditionnel est défini. Ce qui permet aux utilisateurs de prendre une décision « démocratique » conduisant aux services les plus appropriés. Un autre type de Skyline de services est également discuté dans cette thèse. Il s’agit d’un Skyline de Services de nature graduelle et se fonde sur une relation de dominance floue. Comme résultat, les services Web présentant un meilleur compromis entre les paramètres QoS sont retenus, alors que les services Web ayant un mauvais compromis entre les QoS sont exclus. Finalement, nous avons aussi absorbé le cas où les QoS décrivant les services Web sont entachés d’incertitude. La théorie des possibilités est utilisée comme modèle de l’incertain. Ainsi, un Skyline de Services possibilité est proposé pour permettre à l’utilisateur de sélectionner les services Web désirés en présence de QoS incertains. De riches expérimentations ont été conduites afin d’évaluer et de valider toutes les approches proposées dans cette thèse / As we move from a Web of data to a Web of services, enhancing the capabilities of the current Web search engines with effective and efficient techniques for Web services retrieval and selection becomes an important issue. In this dissertation, we present a framework that identifies the top-k Web service compositions according to the user fuzzy preferences based on a fuzzification of the Pareto dominance relationship. We also provide a method to improve the diversity of the top-k compositions. An efficient algorithm is proposed for each method. We evaluate our approach through a set of thorough experiments. After that, we consider the problem of Web service selection under multiple users preferences. We introduce a novel concept called majority service skyline for this problem based on the majority rule. This allows users to make a “democratic” decision on which Web services are the most appropriate. We develop a suitable algorithm for computing the majority service skyline. We conduct a set of thorough experiments to evaluate the effectiveness of the majority service skyline and the efficiency of our algorithm. We then propose the notion of α-dominant service skyline based on a fuzzification of Pareto dominance relationship, which allows the inclusion of Web services with a good compromise between QoS parameters, and the exclusion ofWeb services with a bad compromise between QoS parameters. We develop an efficient algorithm based on R-Tree index structure for computing efficiently the α-dominant service skyline. We evaluate the effectiveness of the α-dominant service skyline and the efficiency of the algorithm through a set of experiments. Finally, we consider the uncertainty of the QoS delivered by Web services. We model each uncertain QoS attribute using a possibility distribution, and we introduce the notion of pos-dominant service skyline and the notion of nec-dominant service skyline that facilitates users to select their desired Web services with the presence of uncertainty in their QoS. We then developappropriate algorithms to efficiently compute both the pos-dominant service skyline and nec-dominant service skyline. We conduct extensive sets of experiments to evaluate the proposed service skyline extensions and algorithms

Cette thèse s'intéresse à la place de la ville dans les films, aux qualités de l'urbain mises en avant par le cinéma, et à la portée géopolitique des représentations de la ville pour l'État qui l'abrite et qu'elle incarne. Les films structurent notre imaginaire, mais également notre réel, c'est à dire notre rapport à la réalité, notre lecture du monde au quotidien. Ils font le lien entre nos connaissances et nos croyances. En somme, ils construisent notre regard et orientent nos représentations. C'est à ce titre qu'ils deviennent des outils politiques et participent aux stratégies d'influence étatiques. En focalisant l'analyse sur la représentation ciné-géographique de Hong Kong et sur son impact pour le soft power chinois, ce travail de recherches interroge la métropole hongkongaise et son rapport à la Chine, mais également l'importance nouvelle que la République Populaire accorde au soft power, ainsi que la place que tiennent le cinéma et les représentations cinématographiques de son territoire, dans sa politique d'influence. En prenant en compte les représentations cinématographiques de la métropole hongkongaise produites par Hollywood, cette thèse questionne enfin la manière dont l'Occident se saisit d'un territoire de l' « ailleurs ». À ce titre, elle interroge non seulement la relation spatiale et symbolique entre ici et autre part, mais aussi entre nous et autrui. / This thesis focuses on the role that cities occupy in films, on the urban traits they project, and on the geopolitical values of such representations to the governing State. Films not only provide structure for our imaginations, they also play a part in the perception of ‘realness’: how we perceive the real world in our daily lives, establishing a connection between our knowledge and our beliefs. As such, they construct the framework in which we view the world and also influence our representations and perceptions. As such, they become political tools, used as mass influencers by the State. Focusing on the analysis of how Hong Kong is represented in films and also on the impact these representations have on Chinese soft power, this thesis examines the metropolis of Hong Kong and its relationship with China, but also questions the People’s Republic of China’s newly placed importance on the idea of soft power, as well as the way its territories are represented in films. Taking into account Western approaches of cinematographic representations of Hong Kong, especially those originating from Hollywood, but also representations originating from Hong Kong, this thesis questions the way in which the West appropriates the notion of ‘otherness’. In summary, not only the spatial and symbolic relationship between here and there is examined, but also between them and us.

Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2017-10-05T20:06:57Z No. of bitstreams: 2 Dissertacao- Welder Batista de Oliveira - 2017.pdf: 2420889 bytes, checksum: c26aee2605e42f2a9aecb9ec2523464f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-10-06T11:09:11Z (GMT) No. of bitstreams: 2 Dissertacao- Welder Batista de Oliveira - 2017.pdf: 2420889 bytes, checksum: c26aee2605e42f2a9aecb9ec2523464f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-10-06T11:09:11Z (GMT). No. of bitstreams: 2 Dissertacao- Welder Batista de Oliveira - 2017.pdf: 2420889 bytes, checksum: c26aee2605e42f2a9aecb9ec2523464f (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-21 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Geographic Information Systems have revolutionized geographic research over the past three decades. These systems commonly provide a number of features for processing andanalyzing spatial data, such as spatial join and skyline. Although relevant, the effectiveness of such functionalities is affected by the imprecision of the geographic coordinates obtained by the georeferencing method employed. Moreover, the error contained in the coordinates may present several distributional patterns, which demands the development of solutions that are generalist concerning the error pattern that they can handle properly. Finally, spatial operations are already computationally expensive in their deterministic version, which is aggravated by the introduction of the stochastic component. The pre-sent work presents a general structure of spatial operations solutions robust to imprecise coordinates based on the use of simulations and probabilistic adaptations of heuristics in the literature. In addition, to deal with the problems mentioned, the proposed structure is designed to contemplate the requirements of generality, accuracy and efficiency at levels that enable its practical application. The overall solution structure is composed of the combination of probabilistic versions of heuristics of the deterministic versions of the spatial operations and by Monte Carlo simulations. From that structure, specific solutions - as case studies - are developed for the spatial join and skyline. Theoretical and experimental results demonstrated the potential of the developed solutions to meet the threerequirements established in this work. / Os Sistemas de Informação Geográfica revolucionaram a pesquisa geográfica nas últimas três décadas. Esses sistemas comumente disponibilizam uma série de funcionalidades para processar e analisar dados espaciais, como, por exemplo, a junção espacial e a consulta skyline. Embora relevantes, a eficácia dessas funcionalidades é impactada pela imprecisão das coordenadas geográficas obtidas pelo método de georreferenciamento empregado. Além disso, o erro contido nas coordenadas pode apresentar diversos padrões distribucionais, o que demanda o desenvolvimento de soluções que sejam generalistas quanto ao padrão de erro que conseguem tratar adequadamente. Por fim, operações espaciais já são computacionalmente caras em sua versão determinística, o que se agrava com a introdução do componente estocástico. O presente trabalho apresenta uma estrutura geral para o desenvolvimento de soluções para operações espaciais robustas a coordenadas imprecisas. Além disso, para lidar com os problemas mencionados, a estrutura proposta é projetada para contemplar os requisitos de generalidade, eficácia e eficiência em patamares que viabilizem sua aplicação prática. A estrutura geral de solução é composta pela combinação de versões probabilísticas de heurísticas das versões determinísticas das operações espaciais e por simulações de Monte Carlo. A partir dela, são desenvolvidas as soluções específicas – como estudo de caso - para a skyline espacial e da junção espacial. Resultados teóricos e experimentais demonstraram o potencial das soluções desenvolvidas em atender aos três requisitos estabelecidos nesse trabalho.

Enclosed herein, in accordance with the requirements of the Department of English, College of Humanities and Sciences, and the VCU Graduate School, Virginia Commonwealth University, Richmond, Virginia, regarding thesis submission, arrangement, and abstraction, is the novel entitled Skyline, in which one Jameson Price, of Fredericksburg, Virginia, aged 19, embarks upon a journey of self-exploration, financial gain, and physical labor, and experiences for the first time (or maybe second) the tumults of love. Upon his enrolment in the Civilian Conservation Corps (CCC) in 1936, he is taken to Camp Saddleback, near New Puckett, Virginia, situated on the Blue Ridge Mountains to the east of the Shenandoah Valley. Here he assists in the creation of the Shenandoah National Park, and develops and explores relationships with fellow CCC boys and local residents—both positive and negative relationships, all with consequences that will affect all of their lives, forever.

Skyline analysis is important for multi-criteria decision making applications. The data in some of these applications are inherently uncertain due to various factors. Although a considerable amount of research has been dedicated separately to efficient skyline computation, as well as modeling uncertain data and answering some types of queries on uncertain data, how to conduct skyline analysis on uncertain data remains an open problem at large. In this thesis, we tackle the problem of skyline analysis on uncertain data. We propose a novel probabilistic skyline model where an uncertain object may take a probability to be in the skyline, and a p-skyline contains all the objects whose skyline probabilities are at least p. Computing probabilistic skylines on large uncertain data sets is challenging. An uncertain object is conceptually described by a probability density function (PDF) in the continuous case, or in the discrete case a set of instances (points) such that each instance has a probability to appear. We develop two efficient algorithms, the bottom-up and top-down algorithms, of computing p-skyline of a set of uncertain objects in the discrete case. We also discuss that our techniques can be applied to the continuous case as well. The bottom-up algorithm computes the skyline probabilities of some selected instances of uncertain objects, and uses those instances to prune other instances and uncertain objects effectively. The top-down algorithm recursively partitions the instances of uncertain objects into subsets, and prunes subsets and objects aggressively. Our experimental results on both the real NBA player data set and the benchmark synthetic data sets show that probabilistic skylines are interesting and useful, and our two algorithms are efficient on large data sets, and complementary to each other in performance.