Proposant une approche méthodologique fondée sur la sémiologie des indices et la sémiotique narrative, notre travail doctoral sous convention CIFRE pour EDF R&D s’attache à comprendre le fonctionnement structural et narratif des représentations du changement climatique dans différentes sphères sociales en France. Partant du caractère scientifique de l’Objet de recherche, l’étude s’intéresse aux discours forgés par les climatologues, la presse de vulgarisation scientifique, trois titres de la presse quotidienne nationale et les discours profanes au travers d’entretiens collectifs, selon une temporalité commune, de novembre 2009 à mars 2010. La « Une » des quotidiens et des magazines de vulgarisation scientifique est alors considérée comme un marqueur social et historique fort, capable de construire les représentations relatives au changement climatique. Le corpus de presse d’information fonde les représentations tant du phénomène climatique que des événements médiatiques qui lui donnent une existence. Le recours à la sémiotique narrative permet une comparaison de corpus de natures différentes, afin de prendre la mesure de la circulation entre les différentes sphères sociales visitées. L’objectif étant une compréhension globale des représentations climatiques, permettant une réflexion sur les mythes dont nos sociétés se nourrissent pour se construire, et sur le possible ré-enchantement de ces mythes. / This doctoral research, conducted through a CIFRE agreement with EDF R&D, aims to understand the structural and narrative organization of climate change representations through four different social spheres in France. First considered as a scientific topic, climate change representations are analysed throughout climate scientists and profane discourses, but also throughout documents such as science popularization magazines and three French newspapers, which of the front pages are considered as a social and historical tracer, particularly during the period running from November 2009 to March 2010. Informative press corpus enables to construct representations of global warming and of the media events that participate to their media life. The use of narrative semiotic methodology allows a comparative study through the different corpuses, in order to spot out the hypothetical circulation of these representations. The eventual aim is a global understanding of climate representations, opening the way for a consideration of the different myths as a basement of our societies, willing to reinvent themselves through new social and cultural myths.

No contexto da gerência de memória em sistemas operacionais, vários grupos de pesquisa desenvolvem trabalhos na área de algoritmos para gerência de memória virtual e alguns algoritmos para substituição de páginas têm sido propostos na literatura recente. No entanto, essas propostas não chegaram a um algoritmo que resolva satisfatoriamente o problema de desempenho na gerência de memória. Ainda não existe um consenso entre os pesquisadores de como essa questão deve ser tratada de maneira eficiente, e as propostas de algoritmos desenvolvidas possuem grande sobrecarga devido à sua complexidade. O objetivo deste trabalho é propor uma forma eficiente de gerenciar a memória com a composição de técnicas de busca, posicionamento e substituição de páginas. A hipótese aqui adotada é que para tratar o problema da gerência da memória é melhor consumir recursos computacionais determinando quais páginas deveriam estar na memória em um determinado instante de tempo do que gastar recursos determinando qual página será retirada da memória. A tese apresenta uma reanálise dos principais trabalhos que têm como objetivo o desempenho da gerência de memória, tornando possível retirar conclusões e ideias sobre quais fatores influenciam de maneira positiva com relação ao desempenho do sistema. A partir deste estudo, é determinado o conceito de qualidade do conteúdo da memória e criada uma métrica para medi-la. Aplicando tal conceito, formula-se um método sistêmico de construção de algoritmos de gerência de memória. Realiza-se uma aplicação desse método, criando-se então, os algoritmos RR+ng e RRlock+ng. A métrica é aplicada em simulações na fase final do método, mostrando-se adequada para realizar as análises. Os resultados obtidos mostram que a hipótese tratar o problema da gerência da memória, consumindo recursos computacionais determinando quais páginas devem estar na memória ao invés de quais devem deixá-la mostrou-se válida e parece promissora. / When it comes to memory management in operating systems, many research groups have been developing works in the memory management algorithms area and some page replacement algorithms have been proposed in the recent literature. Such proposals were not successful in developing algorithms that worked well as far as the performance in memory management is concerned. There is no consensus among the researches about how this problem can be treated efficiently, and the algorithms proposed have high overhead because of their complexity. The objective of this work is to propose an efficient memory management with the composition of page fetch, placement and replacement techniques. This thesis hypothesis is that to treat the memory management problem it is better to consume computational resources determining which pages must be in the memory in a given time than to waste resources defining which pages would be evicted from the memory. This work presents a reanalysis of the main works whose objective is memory management performance, making it possible to draw different conclusions and ideas about what factors may have a positive influence with respect to system performance. This study develops both the concept of quality of memory contents and a metric to measure it. Besides, a systemic method to create memory management algorithms is devised, applying the concept just created. Then, the method is followed, creating the RR+ng and RRlock+ng algorithms. In the final phase of the method, the metric is applied in simulations, proving to be adequate to perform the analysis. The results show that the idea of treating the memory management problem, consuming computational resources to determine which pages must be in the memory instead of which ones must leave it, hold true and seems to be promising.

Electronic commerce (e-commerce) markets provide benefits for both buyers and sellers; however, because of cyber security risks consumers are reluctant to transact online. Trust in e-commerce is paramount for adoption. Trust as a subject for research has been a term considered in depth by numerous researchers in various fields of study, including psychology and information technology. Various models have been developed in e-commerce to alleviate consumer fears, thus promoting trust in online environments. Third-party web seals and online scanning tools are some of the existing models used in e-commerce environments, but they have some deficiencies, e.g. failure to incorporate compliance, which need to be addressed. This research proposes an e-commerce assurance model for safe online shopping. The machine learning model is called the Page ranking analytical hierarchy process (PRAHP). PRAHP builds complementary strengths of the analytical hierarchy process (AHP) and Page ranking (PR) techniques to evaluate the trustworthiness of web attributes. The attributes that are assessed are Adaptive legislation, Adaptive International Organisation for Standardisation Standards, Availability, Policy and Advanced Security login. The attributes were selected based on the literature reviewed from accredited journals and some of the reputable e-commerce websites. PRAHP’s paradigms were evaluated extensively through detailed experiments on business-to-business, business-to-consumer, cloud-based and general e-commerce websites. The results of the assessments were validated by customer inputs regarding the website. The reliability and robustness of PRAHP was tested by varying the damping factor and the inbound links. In all the experiments, the results revealed that the model provides reliable results to guide customers in making informed purchasing decisions. The research also reveals hidden e-commerce topics that have not received attention, which generates knowledge and opens research questions for future researchers. These ultimately made significant contributions in e-commerce assurance, in areas such as security and compliance through the fusing of AHP and PR, integrated into a decision table for alleviating trustworthiness anxiety in various e-commerce transacting partners, e-commerce platforms and markets. / College of Engineering, Science and Technology / D. Phil. Information Systems

社群行銷為互動性與即時性很高的行銷模式，對企業而言日趨重要。透過良好的社群媒體經營，可以使企業提高討論聲量與品牌價值，進而帶動銷售達到透過網路引導購買而獲利的效果。故如何善加利用現今最成功的社群媒體Facebook粉絲專頁是企業行銷的成功關鍵因素之一。 本研究鎖定銀行業做研究主體，擷取2016年整年度的資料以個案分析法的方式深入探討台灣前五名銀行業粉絲專頁之經營方式與互動程度。本研究透過類目建構中的分類標準包含多媒體運用性、資訊性、顧客支援性、組織設定做官方貼文的訊息策略分析，瞭解其優勢策略和品牌區隔。本文並以粉絲專頁定義的KPI指標和數據的量化分析，運用多元回歸分析整合五間粉絲專頁資訊，歸納出銀行業在台灣成功的粉絲專頁之行銷模式。 根據以上分析之經營數據與國外粉絲專頁案例，本研究針對官方貼文的內容面給予較理想的粉絲專頁經營策略，以影片類型和抽獎活動主題為主軸並搭配其他貼文模式可以提升粉絲的總反應程度，本文之行銷建議讓台灣銀行業未來社群行銷發展能更有效率且提升整體商業價值。故本研究之分析架構可以運用到不同的產業類型中給予經營參考，未來後續研究也可以再加入不同反應變數或不同的社群媒體做更深入更全面性的社群媒體品牌經營。 / Social media marketing is an highly interative and high-quality maketing method, It is more important for interprises these days. By running a well social media can improve the business popularity and brand value, or even drive sales to increase profit. So how to make good use of most popular social media Facebook Fan page is the key to success of business marketing. The study focuses on the banking industry, using content analysis to explore the 2016 entire year’s data of the top five bank’s fanpage in Taiwan. Through category of construction classification, the study analysis the type, theme, interation and time of official posts to understand its advantages and strategies. Furthermore, the study uses muti regression to sum up the successful fan page marketing model of banking industry in Taiwan. Based on the above analysis of operating data and success cases in foreign countries, the study hopes to provide more ideal business proposals so that the development of social media in Taiwanese banking industy can be more efficient and enhance the commercial value. Therefore, the analysis structure of the study can be applied to different types of industries to give reference for business, the future studies can also add different variables or other social media to do more comprehecsive social media brand management.

No contexto da gerência de memória em sistemas operacionais, vários grupos de pesquisa desenvolvem trabalhos na área de algoritmos para gerência de memória virtual e alguns algoritmos para substituição de páginas têm sido propostos na literatura recente. No entanto, essas propostas não chegaram a um algoritmo que resolva satisfatoriamente o problema de desempenho na gerência de memória. Ainda não existe um consenso entre os pesquisadores de como essa questão deve ser tratada de maneira eficiente, e as propostas de algoritmos desenvolvidas possuem grande sobrecarga devido à sua complexidade. O objetivo deste trabalho é propor uma forma eficiente de gerenciar a memória com a composição de técnicas de busca, posicionamento e substituição de páginas. A hipótese aqui adotada é que para tratar o problema da gerência da memória é melhor consumir recursos computacionais determinando quais páginas deveriam estar na memória em um determinado instante de tempo do que gastar recursos determinando qual página será retirada da memória. A tese apresenta uma reanálise dos principais trabalhos que têm como objetivo o desempenho da gerência de memória, tornando possível retirar conclusões e ideias sobre quais fatores influenciam de maneira positiva com relação ao desempenho do sistema. A partir deste estudo, é determinado o conceito de qualidade do conteúdo da memória e criada uma métrica para medi-la. Aplicando tal conceito, formula-se um método sistêmico de construção de algoritmos de gerência de memória. Realiza-se uma aplicação desse método, criando-se então, os algoritmos RR+ng e RRlock+ng. A métrica é aplicada em simulações na fase final do método, mostrando-se adequada para realizar as análises. Os resultados obtidos mostram que a hipótese tratar o problema da gerência da memória, consumindo recursos computacionais determinando quais páginas devem estar na memória ao invés de quais devem deixá-la mostrou-se válida e parece promissora. / When it comes to memory management in operating systems, many research groups have been developing works in the memory management algorithms area and some page replacement algorithms have been proposed in the recent literature. Such proposals were not successful in developing algorithms that worked well as far as the performance in memory management is concerned. There is no consensus among the researches about how this problem can be treated efficiently, and the algorithms proposed have high overhead because of their complexity. The objective of this work is to propose an efficient memory management with the composition of page fetch, placement and replacement techniques. This thesis hypothesis is that to treat the memory management problem it is better to consume computational resources determining which pages must be in the memory in a given time than to waste resources defining which pages would be evicted from the memory. This work presents a reanalysis of the main works whose objective is memory management performance, making it possible to draw different conclusions and ideas about what factors may have a positive influence with respect to system performance. This study develops both the concept of quality of memory contents and a metric to measure it. Besides, a systemic method to create memory management algorithms is devised, applying the concept just created. Then, the method is followed, creating the RR+ng and RRlock+ng algorithms. In the final phase of the method, the metric is applied in simulations, proving to be adequate to perform the analysis. The results show that the idea of treating the memory management problem, consuming computational resources to determine which pages must be in the memory instead of which ones must leave it, hold true and seems to be promising.

Cette thèse porte sur l'indexation et l'interrogation de pages Web. Dans ce cadre, nous proposons un nouveau modèle : BlockWeb, qui s'appuie sur une décomposition de pages Web en une hiérarchie de blocs visuels. Ce modèle prend en compte, l'importance visuelle de chaque bloc et la perméabilité des blocs au contenu de leurs blocs voisins dans la page. Les avantages de cette décomposition sont multiples en terme d'indexation et d'interrogation. Elle permet notamment d'effectuer une interrogation à une granularité plus fine que la page : les blocs les plus similaires à une requête peuvent être renvoyés à la place de la page complète. Une page est représentée sous forme d'un graphe acyclique orienté dont chaque nœud est associé à un bloc et étiqueté par l'importance de ce bloc et chaque arc est étiqueté la perméabilité du bloc cible au bloc source. Afin de construire ce graphe à partir de la représentation en arbre de blocs d'une page, nous proposons un nouveau langage : XIML (acronyme de XML Indexing Management Language), qui est un langage de règles à la façon de XSLT. Nous avons expérimenté notre modèle sur deux applications distinctes : la recherche du meilleur point d'entrée sur un corpus d'articles de journaux électroniques et l'indexation et la recherche d'images sur un corpus de la campagne d'ImagEval 2006. Nous en présentons les résultats. / This thesis is about indexing and querying Web pages. We propose a new model called BlockWeb, based on the decomposition of Web pages into a hierarchy of visual blocks. This model takes in account the visual importance of each block as well as the permeability of block's content to their neighbor blocks on the page. Splitting up a page into blocks has several advantages in terms of indexing and querying. It allows to query the system with a finer granularity than the whole page: the most similar blocks to the query can be returned instead of the whole page. A page is modeled as a directed acyclic graph, the IP graph, where each node is associated with a block and is labeled by the coefficient of importance of this block and each arc is labeled by the coefficient of permeability of the target node content to the source node content. In order to build this graph from the bloc tree representation of a page, we propose a new language : XIML (acronym for XML Indexing Management Language), a rule based language like XSLT. The model has been assessed on two distinct dataset: finding the best entry point in a dataset of electronic newspaper articles, and images indexing and querying in a dataset drawn from web pages of the ImagEval 2006 campaign. We present the results of these experiments.

On présente les machines-applications, c'est-à-dire les machines supportant une seule application donnée. On décrit les fonctions classiques d'un système de traitement de texte. On aborde ensuite l'application effective des phases de conception et de réalisation pour la construction de la machine REDAK. On développe les problèmes rencontres dans la réalisation d'une machine-application en utilisant le système d'exploitation d'une machine orientée système. On présente les fonctions du système de traitement de texte REDAK et on décrié le systeme d'exploitation utilisé.

Decline in cardiac pump function is a hallmark of aging where mitochondrial decay is an important underlying cause. Although certainly multifactorial in nature, both dysfunction of the machinery involved in the chemiosmotic process of energy transduction and lower capacity to maintain fatty acid-driven respiration are identified as intrinsic factors of mitochondrial decay in the aged myocardium. Age-associated destabilization of electron transport supercomplexes as a potential factor of mitochondrial decay in the rat heart. Defective operation of the electron transport chain (ETC) constitutes a key mechanism involved in the age-associated loss of mitochondrial energy metabolism. Nevertheless, the molecular events underlying inefficient electron flux that ultimately leads to higher superoxide appearance and impaired respiration are not fully known. As recent biophysical evidence shows that the ETC may form large macromolecular assemblies (i.e. supercomplexes) that disintegrate in certain pathologies (e.g. heart failure or Barth syndrome) reminiscent of aging, we investigated the hypothesis that alterations in supercomplexes are partly responsible for the age-related loss of cardiac ETC function. In this dissertation, age-associated changes in supercomplex organization and stability were investigated in subsarcolemmal (SSM) and interfibrillary (IFM) mitochondria isolated from cardiac tissue from young (3-5 months) and old (24-28 months) male Fischer 344 rats. Blue native-PAGE (BN-PAGE) analysis of digitonin-solubilized mitochondrial membranes coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to investigate supercomplex organization. Results show that both SSM and IFM display supercomplexes comprised of various stoichiometries of complexes I, III and IV (never complex II), which typically organize as high mass (1500-2300 kDa) assemblies containing up to four copies of complex IV (i.e. I���III���IV[subscript N]-type supercomplexes). Interestingly, analysis of IFM proteins showed that, in general, supercomplex levels declined by up to 15 % (p < 0.05) with age; however, different degrees of supercomplex deterioration were observed, depending on the particular supercomplex investigated. Supercomplexes of the highest molecular weights (i.e. 1900-2300 kDa), which were also composed of the most complex stoichiometries (i.e. I1III2IVN, N ��� 2), were primarily lost with age. In particular, I���III���IV���, I���III���IV��� and I���III���IV��� supercomplexes were found to decline by 13% (p < 0.05), 30% (p < 0.05) and 45% (p < 0.05), respectively, on an age basis. Therefore, the age-associated loss of supercomplexes in IFM stems from destabilization of the assemblies that comprise several copies of complex IV, which could partially limit proper electron transfer to O��� for its reduction, affecting mitochondrial respiratory capacity. In contrast to IFM, the aging defects of SSM supercomplexes appeared to be confined to the assembly comprised of only one copy of complex IV (I���III���IV���, 1700 kDa) (37% loss; p = 0.06), while the higher molecular weight supercomplex sub-types that were most affected in IFM (i.e. I���III���IV[subscript N], N ��� 2) were not significantly altered with age. Thus, the results from this dissertation indicate that mitochondria from different subcellular locations in the myocyte show different degrees of supercomplex destabilization in the aging rat heart. The more robust supercomplex deficits noted for IFM fit well with previous observations that electron transport characteristics of this subpopulation are more adversely affected with age than SSM. Although the underlying factor(s) of supercomplex deterioration are not fully known, the hypothesis that age-related alterations of certain constituents of the IMM (e.g. cardiolipin) may be important factors of supercomplex destabilization in cardiac mitochondria was investigated in this dissertation. To this end, LC-MS/MS characterization of supercomplex proteins and HPLC analysis of cardiolipin were used as approaches to elucidate potential factor(s) of supercomplex destabilization in the aging rat heart. Age-related alterations of cardiolipin levels and its acyl-chain content showed a strong parallel to the age-associated destabilization of supercomplexes. Specifically, cardiolipin levels declined by 10% (p < 0.05) in IFM, the mitochondrial subpopulation displaying the highest degree of supercomplex deterioration. In addition, the content of (18:2)���-cardiolipin, the predominant species in the heart, was found to decline by 50% (p < 0.05) on average in both populations of cardiac mitochondria. Therefore, the data presented in this dissertation indicate that changes in cardiolipin may be at least one of the factors involved in supercomplex destabilization in the aging heart. Age-related decline in carnitine palmitoyltransferase I (CPT1) activity as a mitochondrial lesion that limits fatty acid catabolism in the rat heart. Loss of fatty acid utilization, another intrinsic factor of mitochondrial decay in the aged myocardium, has been associated with age-related alterations in the activity of carnitine palmitoyltransferase 1 (CPT1), the rate-controlling enzyme for overall fatty acid ��-oxidation. Nevertheless, the exact molecular mechanism involved in the age-related loss of fatty acid-driven bioenergetics is not fully understood. In this dissertation, it was also investigated whether the aging lesion for fatty oxidation lies in a particular mitochondrial subpopulation or more generally results from cardiac decrements in L-carnitine levels. In order to clarify the role of each one of these factors, the effect of long-term dietary supplementation with the L-carnitine analogue, acetyl-L-carnitine (ALCAR), was also investigated. Results show that aging selectively decreases CPT1 activity in IFM by reducing enzyme catalytic efficiency for palmitoyl-CoA. IFM displayed a 28% (p < 0.05) loss of CPT1 activity, which correlated with a decline (41%, p < 0.05) in palmitoyl-CoA-driven state 3 respiration. Interestingly, SSM had preserved enzyme function and efficiently utilized palmitate. Analysis of IFM CPT1 kinetics showed both diminished V[subscript max] and K[subscript m] (60% and 49% respectively, p < 0.05) when palmitoyl-CoA was the substrate. However, no age-related changes in enzyme kinetics were evident with respect to L-carnitine. ALCAR supplementation restored CPT1 activity in heart IFM, but not apparently through remediation of L-carnitine levels. Rather, ALCAR influenced enzyme activity over time, potentially by modulating conditions in the aging heart that ultimately affect palmitoyl-CoA binding and CPT1 kinetics. In conclusion, this dissertation presents a characterization of age-associated alterations in the macromolecular organization of the IMM components that could partly explain the loss of mitochondrial oxidative capacity that affects the aging heart. In addition, the characterization of an age-related lesion of the controlling enzyme for ��-oxidation is presented as another important factor that limits mitochondrial function and energy metabolism in cardiac mitochondria. / Graduation date: 2013

<p>This study reports on a proteomic analysis of sorghum proteomes in response to salt and hyperosmotic stresses. Two-dimensional gel electrophoresis (2DE) in combination with mass spectrometry (MS) was used to separate, visualise and identify sorghum proteins using both sorghum cell suspension cultures and whole plants. The sorghum cell suspension culture system was used as a source of culture filtrate (CF) proteins. Of the 25 visualised CBB stained CF spots, 15 abundant and well-resolved spots were selected for identification using a combination of MALDI-TOF and MALDI-TOFTOF MS, and database searching. Of these spots, 14 were positively identified as peroxidases, germin proteins, oxalate oxidases and alpha-galactosidases with known functions in signalling processes, defense mechanisms and cell wall metabolism.</p>

<p>This study reports on a proteomic analysis of sorghum proteomes in response to salt and hyperosmotic stresses. Two-dimensional gel electrophoresis (2DE) in combination with mass spectrometry (MS) was used to separate, visualise and identify sorghum proteins using both sorghum cell suspension cultures and whole plants. The sorghum cell suspension culture system was used as a source of culture filtrate (CF) proteins. Of the 25 visualised CBB stained CF spots, 15 abundant and well-resolved spots were selected for identification using a combination of MALDI-TOF and MALDI-TOFTOF MS, and database searching. Of these spots, 14 were positively identified as peroxidases, germin proteins, oxalate oxidases and alpha-galactosidases with known functions in signalling processes, defense mechanisms and cell wall metabolism.</p>