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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Conception d'un famework pour la relaxation des requêtes SPARQL / Design of a Framework for Cooperative Answering of SPARQL Query in RDF Database

Fokou Pelap, Géraud 21 November 2016 (has links)
Une ontologie (ou base de connaissances) est une représentation formelle de connaissances sous la forme d'entités et de faits sur ces entités. Ces dernières années de nombreuses ontologies ont été développées dans des contextes académiques et industriels. Elles sont généralement définies à l’aide du langage forme lRDF et interrogées avec le langage de requêtes SPARQL. Une connaissance partielle du contenu et de la structure d’une ontologie peut amener les utilisateurs à exécuter des requêtes qui retournent un résultat vide de réponses, considéré comme insatisfaisant. Parmi les techniques d’interrogation coopératives développées pour résoudre ce problème se trouve la technique de relaxation de requêtes. Elle consiste à affaiblir les conditions exprimées dans les requêtes pour retourner des résultats alternatifs à l'utilisateur. En étudiant les travaux existants sur la relaxation de requêtes SPARQL nous avons constaté qu’ils présentent plusieurs limitations :(1) ils ne permettent pas de définir précisément la relaxation à effectuer tout en offrant la possibilité de contrôler le processus de relaxation (2) ils n’identifient pas les causes réelles d'échec de la requête formulée par l'utilisateur et (3) ils n’intègrent pas d’outils interactifs pour mieux exploiter les techniques de relaxation proposées. Pour répondre à ces limitations, ce travail de thèse propose un framework pour la relaxation de requêtes SPARQL. Ce framework inclut un ensemble d'opérateurs de relaxation des requêtes SPARQL permettant de relaxer incrémentalement des parties précises de la requête utilisateur tout en contrôlant la pertinence des réponses alternatives retournées par rapport aux besoins exprimés par l’utilisateur dans sa requête. Notre framework propose également plusieurs algorithmes qui identifient les causes d’échec de la requête utilisateur et les requêtes qui réussissent (c'est-à-dire, qui ont des résultats) ayant un nombre maximal de conditions de la requête initialement exprimée. Ces informations permettent à l’utilisateur de mieux comprendre pourquoi sa requête échoue et d’exécuter des requêtes qui retournent des résultats alternatifs.Enfin, notre framework propose des stratégies de relaxation qui élargissent les conditions de la requête utilisateur en s’appuyant sur les causes d’échec de celle-ci. Ces stratégies permettent de réduire le temps d’exécution du processus de relaxation par rapport à l’approche classique, qui consiste à exécuter les requêtes relaxées, en fonction de leur similarité avec la requête utilisateur, jusqu’à l’obtention d’un nombre satisfaisant de résultats alternatifs. Les contributions proposées dans ce framework ont été implémentées et validées par des scénarios et expérimentations basés sur le banc d'essai LUBM. Ils montrent l’intérêt de nos contributions par rapport à l'état de l'art. / Ontology (or Knowledge base) is a formal representation of knowledge as entities and facts related to these entities. In the past years, several ontologies have been developed in academic and industrial contexts.They are generally defined with RDF language and querying with SPARQL language. A partial knowledge of instances and schema of ontology may lead user to execute queries that result in empty answers, considered as unsatisfactory. Among cooperative querying techniques which have been developed to solve the problem of empty answers, query relaxation technique is the well-known and used. It aims at weakening the conditions expressed in the original query to return alternative answers to the user. Existing work on relaxation of SPARQL queries we suffer from many drawbacks : (1) they do not allow defining in precise way the relaxation to perform with the ability to control the relaxation process (2) they do not identify the causes of failure of the request expressed by the user and (3) they do not include interactive tools to better exploit the relaxation techniques proposed. To address these limitations, this thesis proposes an advanced framework forquery relaxation SPARQL. First, this framework includes a set of relaxation operators dedicated to SPARQLqueries, to incrementally relax specific parts of the user request while controlling the relevance of the alternative responses returned w.r.t. to the user needs expressed in his request. Our framework also provides both several algorithms that identify the causes of failure of the user query and queries that are successful with a maximum number of conditions initially expressed in the failing request. This information allows the user to better understand why his request fails and execute queries that return non-empty alternative results. Finally,our framework offers intelligent relaxation strategies that rely on the causes of query failure. Such strategies reduce the execution time of the relaxation process compared to the traditional approach, which executes relaxed requests, based on their similarity to the user request, until a number of satisfactory alternative results is obtained. All contributions proposed in this framework were implemented and validated by experiments and scenarios based on the tests bench LUBM. They show the interest of our contributions w.r.t. the state of theart.
52

Crop residue management in oil palm plantations : soil quality, soil biota and ecosystem functions

Tao, Hsiao-Hang January 2017 (has links)
The application of crop residues is one of the most common agricultural practices used to maintain soil ecosystems and crop productivity. This thesis focuses on the oil palm (Elaeis guineensis) agroecosystem, an important tropical crop that has expanded rapidly over the past four decades. Both land conversion and business-as-usual practices within the plantations have contributed to soil degradation. The application of oil palm residues, such as empty fruit bunches (EFB) and oil palm fronds, are thought to have positive effects on the soil ecosystem; yet there is currently a deficit of knowledge on their effectiveness. This thesis aims to examine the effects of oil palm residue application on soil physicochemical properties, soil biota, and ecosystem functions. It reports the results of extensive field trials, sample collection, and statistical analysis of crop residue applications in oil palm plantations in Central Sumatra, Indonesia. Four key results emerged from the thesis. First, in this study site land conversion from secondary forest to oil palm does not affect litter decomposition rate, but positively influences soil fauna activity. Second, there is greater soil fauna activity following EFB application than oil palm fronds or chemical fertilizers, and the fauna activity is highly associated with changes in soil chemical properties and soil moisture conditions. Third, EFB application enhances soil ecosystem functions, through the direct provision of organic matter, and by influencing soil biota. Finally, over 15 years of application, EFB appears to be effective in maintaining or increasing annual crop yield in comparison to chemical fertiliser treatment. Temporal changes in crop yield under EFB application appear to be associated with climatic conditions and soil organic carbon. Overall, these findings improve our understanding of the potential of oil palm residue applications to increase soil quality, soil biota, and ecosystem functions. They also provide useful information for a wider audience of soil ecologists, agricultural managers, and policy makers to improve sustainable management of the oil palm ecosystem.
53

The empty-nest stage of life : a comparative study of women and men facing transition

Kaplan, Ernest January 1989 (has links)
This thesis encompasses a study of the empty-nest stage of life. For the purposes of this study, the above-mentioned stage was defined as that period in the family when the youngest child matriculates. Thirty-five empty-nest couples were interviewed during 1984, in the city of Port Elizabeth, South Africa. The mean age of the subjects was 49.5, and the standard deviation was 4.9. The couples were asked about their attitudes towards the empty-nest, using a structured questionnaire, the Family Attitude Survey (FAS). This survey consisted of nine-point attitude statements, which focused on theoretical issues pertinent to this stage, viz. children are on-time or off-time with regard to major life events, impact of children leaving home on the parents, degree of parental involvement with children, parent-child relationships, ageing, sexuality, menopause, work-career, and attitudes towards the past, future and death. The general purpose of the present study was to determine the extent to which the empty-nest stage of life constitutes a negative crisis period, or a positive period of stability and growth for the empty-nest parents. Overall, it was concluded that the empirical evidence depicting the empty- nest stage of life as a positive period of stability and growth rather than a negative crisis period, is persuasive for some of the empty-nest parents in the present study, in view of the empirical findings regarding certain of the above-mentioned theoretical issues examined in the present thesis. Notwithstanding this, it was deemed essential to qualify the above conclusion, given the fact that the same and other respondents experienced difficulty with the following issues, viz. children being off-time with regard to major life events, the departure of children from the home, overinvolvement with children, problematic relationships with them, perceptions of themselves as failures as parents, inability to accept their own ageing, problems with changing sexuality, diminishing enjoyment in their occupations, and lack of prospects for future career advancement, negative preoccupation with the past and future, anxiety about death, and an impoverished marital relationship. It was also demonstrated empirically that wives experience particular psychological problems at this time, viz., firstly, they are more adversely affected by their children's departure from the home than their husbands, secondly, they undergo a rehearsal for widowhood more frequently than them, and thirdly, a minority of them are unable to come to terms with the menopause. Finally, the finding that the majority of wives experienced relief with the onset of the menopause when viewed from the perspectives of general emotional impact, children, and the spousal relationship, conflicts with existing theories in this area. However, it is supported by and large by the majority of empirical studies.
54

Optimalizace toku prázdných obalů v automotivu / Optimization of empty packaging flow in automotive

Feshyna, Olga January 2017 (has links)
The diploma thesis focuses on the optimization of the empty packaging flow in automotive. The aim of the thesis is to optimize empty packaging flow in warehouse area and to analyze the possibility of implementation a scanning system and an electronic document for communication with suppliers. The first part explains the theoretical background, presents the automotive industry and current market trends. Then follows a brief introduction of TPCA, where the work was created. The theoretical part presents the concept of lean management, its main tools and components, illustrated on concrete examples of TPCA. The theoretical knowledge follows the practical part. The diploma thesis project focuses on the optimization of empty packaging flow and the implementation of a scanning system for loading. Firstly, application part presents the inbound logistics paths and the entire flow of material, after there is deeper analyze and optimization of the empty packaging and loading process itself. The final section compares the baseline and current states.
55

Absence et présence du corps dans l'oeuvre de Jean-Paul Sartre / Absence and Presence of the Human Body in the works of Sartre

Dayan, Mhd Bachar 03 December 2011 (has links)
Mon sujet de thèse est une tentative d’éclairage de l’énigme du corps absent/ présent, obscur, fictif et extraordinaire chez les personnages romanesques et philosophiques d’un grand auteur français du XXe siècle : Jean-Paul Sartre. L’énigme de ce corps obscur traduit dans les œuvres de Sartre une réalité ontologique, charnelle. Or, la description du corps (absent ou présent) chez Sartre est avant tout imaginaire et il y a un nombre infini d’énigmes corporelles dans son œuvre. Elles se cherchent encore des significations. Le savoir encyclopédique de Sartre mérite, et sans limite, une multitude de lectures qui pourraient enrichir durablement la compréhension du texte littéraire de cet auteur. Beaucoup de questions cherchent des réponses bien précises. La recherche de l’absence du corps ou de l’énigme corporelle dans le texte sartrien n’a jamais été l’objet principal d’une étude entière, ce qui nous permet de prétendre à l’originalité d’un nouveau trajet de lecture. Notre étude a pour objectif de définir les modalités, les structures, les emblèmes, le sens et la nature de l’énigme dans l’œuvre de Sartre. Faire une analyse détaillée de l’énigme existentielle du corps surtout mais tout en s’appuyant sur ce que nous pouvons appeler l’herméneutique de l’énigme et les différents aspects de la présence/ absence. Lire Sartre, avec cette nouvelle méthode va tracer, nous l’espérons bien, une nouvelle ligne de recherche et créer une nouvelle dimension dans la compréhension de la philosophie et de l’écriture littéraire de Sartre. / The subject of my thesis is an attempt to shed light on the enigma of the mysterious human body which is fictitious and extraordinary as depicted in the characters of the philosophical works of French writer Jean-Paul Sartre. These contradictions demand an understanding of the ultimate nature of the reality of the body which is both carnal and at the same time real. But the description of the body by Sartre is essentially imaginary and can lead to an infinite number of interpretations The information and facts provided by this author therefore fully deserve an analysis meant to enrich the understanding of his literary works. Such an attempt to solve these riddles through a search for the understanding of the puzzle of the body in the text of Sartre has never been the main subject of a full study. This allows us to claim originality of a new way of understanding his work. Our study aims to determine the structures, symbols, meaning, and nature of this enigma. This dissertation contains a detailed analysis of the existential contradictions of the body primarily based on interpretation of the absence/ presence dilemma. Hence a reading of Sartre with these hopefully more enlightening insights is intended to develop a novel thought process for research and to create a new dimension in the understanding of Sartre’s philosophy and writings.
56

Machine Learning Approach to Forecasting Empty Container Volumes

LIU, YUAN January 2019 (has links)
Background With the development of global trade, the volume of goods transported around the world is growing. And over 90% of world trade is carried by shipping industry, container shipping is the most important way. But with the growth of trade imbalances, the reposition of empty containers has become an important issue for shipping. Accurately predicting the volume of empty containers will greatly assist the empty container reposition plan. Objectives The main aim of this study is to explore the effect of machine learning in predicting empty container volumes, make a performance comparison and analysis with existing empirical methods and mathematical statistics methods. Methods The main method of this study is experiment. In this study I chose the appropriate algorithm model and then trained and tested the model. This study uses the same data sources as the industrial approach, using the same metric to evaluate and compare the performance of machine learning methods and industrial methods.  Results Through experiments, this study obtained the forecasting performance results of five machine algorithms including the LASSO regression algorithm on the Los Angeles Port and Long Beach Port datasets. Metrics are (Mean Square Error) MSE and (Mean Absolute Error) MAE. Conclusions LASSO Regression and Ridge Regression are the best machine learning algorithms for predicting the volume of empty containers. Compared to empirical methods, the single machine learning algorithm performs better and has better accuracy. However, compared with mature statistical methods such as time series, the performance of a single machine learning algorithm is worse than the time series method. Machine learning needs to try to combine multiple models or select more high-correlation feature quantities to improve performance on this prediction problem.
57

Prázdné skořápky. Tři příběhy o relativizaci axiologického jádra demokracie / Empty Shells. Three Tales on the Relativization of the Axiological Core of Democracy

Horák, Filip January 2020 (has links)
Empty Shells. Three Tales on the Relativization of the Axiological Core of Democracy - Abstract JUDr. Bc. Filip Horák The purpose of this thesis is to discuss the problem of gradual softening of the democratic political system's axiological core. Firstly, the thesis illustrates the problem via three tales narrated by Carl Schmitt, Hannah Arendt and Leo Strauss, who in a very similar manner critically analyzed the "axiological leap" leading to the disintegration of fundamental values and principles of democracy. Secondly, the thesis offers a new methodological approach combining empirical functional analysis of the individual values constituting democracy's axiological core (i.e. equality, liberty, justice and dignity) with a teleological approach focusing on the original purposes and functions of these values. Using functional analysis, the thesis examines possible interpretations and functions of the aforementioned values and shows that all of them evince a high degree of vagueness and ambiguity, which makes them so-called "empty shells" that can be filled with almost any content, meaning or function. This is also the main cause of the disintegration of the democracy's axiological core. Thirdly, the thesis theoretically reconstructs the original and stable axiological core using teleological approach....
58

Prázdná veřejná prostranství a jejich potenciál v novodobé struktuře evropského města / Empty public spaces and their potencial in a modern structure of European city

Kuznetcova, Evgeniia January 2016 (has links)
The subject of this work is research of the transformation of public spaces in the modern European city structure. Modern life is changing, but there are more and more examples proving that urban spaces only partially correspond to the changing environment and the demands of people. The result is noticed as „emptying“ of some public spaces, which is characterized by lack of diversity and richness of the physical and social content of space and the subsequent loss of their meaning. This paper aims to describe the emerging „empty“ public spaces, to creat their definition and classification. The work generally examines the current situation of public spaces and describe the factors that cause their transformation. The work also presents an analysis of the problems emerging empty spaces and highlights the possible potential of these areas. Finally, it is described the current trends in the revitalization of empty public spaces, which are an example of their potential use.
59

Empty and filled rhythms:An inquiry into the different cognitive processing of vocal and instrumental rhythms

Cheong, Yong Jeon 23 August 2013 (has links)
No description available.
60

Post-Parenthood Redefined: Race, Class, and Family Structure Differences

Feldman, Karie Ellen 30 July 2010 (has links)
No description available.

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