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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.
101

Demokratiese konsolidasie in Afrika : 'n vergelykende studie tussen Botswana en Mauritius

Slabbert, Nica-Elize 12 1900 (has links)
Thesis (MA (Political Science))--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: Botswana and Mauritius have been operating as stable, multi-party democracies since their independence, in 1966 and 1968 respectively. It is unclear, however, which country is the most consolidated democracy. Therefore, this study compares Botswana and Mauritius, using specific criteria as developed by writers such as Huntington (1991), Linz and Stepan (1996), Przeworski (1996) and Schedler (1998 and 2001) to determine which country is the most consolidated democracy. The criteria used to determine the most consolidated democracy, can broadly be subdivided as follows. Firstly, institutions impacting on democratic consolidation, and the presence of these institutions in Botswana and Mauritius will be studied, such as the rule of law; whether the respective countries are characterised by a system of Presidentialism or Parliamentarianism; the electoral system used; whether elections are competitive, free and fair, and whether these elections resulted in a peaceful change in political power; the presence of a usable state bureaucracy; and lastly, the rankings by Freedom House will be used to determine to what extent citizen political and civil rights are protected and guaranteed. Secondly, the socio-economic factors impacting on the erosion or deepening of democratic consolidation will be studied, with the focus on trends since independence. These factors include the existence of an economic society; per capita income; economic growth and inflation; as well as inequality reduction within the respective countries. Lastly, the social conditions influencing democratic consolidation will also be studied, such as ethnic homogeneity or heterogeneity; the prevalence and size of the middle class as influenced by urbanization and adult literacy; and lastly, the prevalence and role of civil society. Botswana and Mauritius were compared using the above criteria. This study comes to the conclusion that Mauritius is the most consolidated democracy. The following findings support the conclusion that Mauritius is the most consolidated democracy. Mauritius is a rechtsstaat, whilst Botswana is not. In Mauritius, there is a distinction between the position of Head of State and Head of Government, in contrast to the extensive power given to the President in Botswana. There is no single dominant party in Mauritius, whilst the political sphere in Botswana is characterised by the dominance of the BDP since independence. The FPTP electoral system in Mauritius is supplemented by the BLS, in an effort to ensure sufficient representation to minority groups in the National Assembly, whilst Botswana only uses the FPTP electoral system. Elections in Mauritius are considered to be competitive, free and fair, whilst the fairness of Botswana’s elections, given the electoral system, have been questioned. Mauritius also passes Huntington’s Two Turnover test, as there have been three changes in political power, whilst the BDP in Botswana have won every election since independence. Mauritius’ position on the HDI is much better than the position of Botswana, and the consociational compromises agreed upon in Mauritius resulted in a social environment which assists democratic consolidation. Lastly, Mauritius is also characterised by a lively civil society, whilst civil society in Botswana is considered to be a-political and weak.
102

Decision Support for Product Management of Software Intensive Products

Khurum, Mahvish January 2011 (has links)
Context: At the core of choosing what features and level of quality to realize, and thus offer a market or customer, rests on the ability to take decisions. Decision-making is complicated by the diverse understanding of issues such as priority, consequence of realization, and interpretations of strategy as pertaining to the short-term and long-term development of software intensive products. The complexity is further compounded by the amount of decision support material that has to be taken into account, and the sheer volume of possible alternatives that have to be triaged and prioritized; thousands or even tens of thousands of requirements can be the reality facing a company. There is a need to develop the functionality that is strategically most significant, while satisfying customers and being competitive, time efficient, cost effective, and risk minimizing. In order to achieve a balance between these factors, all the stakeholders, within an organization, need to agree on the strategic aspects and value considerations to be considered, and their corresponding relative importance. Objective: The objective of this thesis is to provide enhanced decision support for product managers faced with decision-making challenges. This involves, but is not limited to, enhancing the alignment between the product and portfolio management with respect to product strategies, and enabling the use of value as a basis for product management and development related decisions. Method: A number of empirical studies, set in industry, have been performed. The research methods used span from systematic mapping, and systematic reviews to case studies, all aligned to identify possibilities for improvement, devise solutions, and incrementally evaluate said solutions. Close collaboration with industry partners was at the core of the research presented in this thesis. Result: The MASS method presented in this thesis can be used to evaluate strategic alignment and identify possible root causes for misalignment. To strengthen strategic alignment, the Software Value Map and corresponding decision support material, proposed in the thesis, can be used by product managers for making effective and efficient strategic decisions in relation to portfolios, products and process improvement, following a systematic and aligned process. Conclusions: The area of software product management, in the context of market-driven software intensive product development, is a field with unique challenges. The specifics of the solutions are based on industry case studies performed to gauge state-of-the-art, as well as identify the main challenges. The decision support developed takes the form of maps and frameworks that support software product management on product and portfolio level decisions, strategic alignment, value-based requirements selection, and value-based process improvement.
103

以財務比率預測未來盈餘及股價異常報酬之研究-比較母公司財務報表與合併財務報表

蘇心盈, Su , Hsin_Yin Unknown Date (has links)
在現今的經濟、法律、政治環境下,許多企業因為法律、稅務、競爭策略等之考量,已不再以法律上單一企業個體進行所有商業行為,也許會以成立子公司或透過股權收購擁有或控制其他企業,以達到特定的目的。財務會計準則公報第七號即針對此點,認為在經濟實質重於法律形式之基礎下,當一企業實質上可控制另一企業時,雖然在法律上其為相互獨立的個體,但基於經濟實質之考量,其應屬於同一個體,因此,合併財務報表之規定因應而生。合併財務報表與一般以權益法處理長期投資之母公司財務報表,最大不同處即在對長期股權投資及投資收益之處理,合併財務報表將母公司財務報表中之長期股權投資及投資收益分解為子公司資產、負債及本期淨利之組成要素,再與母公司財務報表合併,此即所謂「全面合併」。理論上,合併財務報表應較母公司財務報表更能清楚表達一經濟個體之財務狀況、經營成果及現金流量,讓報表使用人看的更清楚。 本研究參考Ou and Penman(1989)及 Holthausen and Larcker(1992)之研究,以財務比率預測企業未來每股盈餘變動方向及股價異常報酬方向。以民國八十六年至民國九十年五年間同時編製母公司及合併財務報表之113家上市公司為觀察公司,並以八十六年至八十九年為估計期間,以財務比率分別建構兩套財務報表之預測模式,將預測模式代入民國九十年之中,預測民國九十一年之每股盈餘變動方向以及股價異常報酬方向,再比較兩套財務報表之預測能力。 實證結果發現,因為兩套財務報表在許多項目金額均相異,所以若以財務比率分析一企業,兩套財務報表的確具不同之意涵,但若將財務比率預測每股盈餘變動方向以及股價異常報酬方向,兩套財務報表的預測能力並未通過統計上之顯著差異,無法得到合併財務報表因其資訊內涵較佳,其預測能力較母公司財務報表為佳之結論。在實證過程中,受到資料取得之限制及許多假設的影響,均可能對此研究結果造成影響。
104

Daň z příjmů v kontextu s harmonizací přímých daní v Evropské unii / Income tax in the context of hamonization of direct taxes in the European Union

Zajíčková, Miroslava January 2012 (has links)
- 1 - Abstract The issue of income tax is a topic that is current, whatever the political organization of the country, because it is a fact significantly affecting the political, economic and social conditions, from many different aspects. Individual load, as well as corporate income taxes is one of the key elements that most impact on people and affect their economic behavior, social and political decision-making standard. Income tax in the tax systems is one of the most important taxes, because it is burdening the income of individuals and legal entities, tax payers. Through a greater or lower tax burden on personal and corporate income it is possible to use the legislation in the area of income tax and its setting, in the period of economic stagnation, as an instrument for economic recovery. In the area of tax systems and tax systems of specific countries in the last decade we recorded a relatively significant development. The shift, consisting mainly in the approximation of national tax laws, is in our legal system particularly evident after the enter of Czech Republic to the European Union in 2004. In connection with the gradual expansion of the European Economic Community, of the customs union, common market between Member States and European Union development into as we know it today, with 27 Member...
105

Svenskt sjöförsvar - samverkan eller sammanslagning? : En fallstudie av SOU 2012:48 med fokus på varför Försvarsmakten och Kustbevakningen inte slås samman. / Swedish maritime defence - cooperation or consolidation? : A case study of SOU 2012:48 with focus on why the Swedish defence forces and Coast guard do not consolidate into one.

Forssman, Bengt, Mandéus, Henrik January 2019 (has links)
I takt med att det säkerhetspolitiska omvärldsläget förändrats har frågor kring statens förmåga att möta kriser och rena krigshandlingar accentuerats. En statlig utredning har därför föreslagit att på sikt skapa ett samlat sjöförsvar genom att integrera Kustbevakningen och Marinen i en gemensam myndighet. Riktningen på de politiska besluten har dock gått åt en fördjupad samverkan i stället trots att samverkan mellan Försvarsmakten och Kustbevakningen varit behäftad med svårigheter. Denna studie syftar till att analysera varför man i Sverige valt att utöka samverkan mellan Försvarsmakten och Kustbevakningen. Studien är en kvalitativ fallstudie där WPR-metoden används för att analysera SOU 2012:48 kompletterad med en samtalsintervju av en informant vid Försvarsdepartementet. Teoretisk utgångspunkt utgörs av Sundelius m.fl. forskning kring svensk nationell krishantering. Sammanfattningsvis kan konstateras att det inte finns någon politisk vilja till en sammanslagning. Detta grundar sig på en generell ovilja att blanda civila och militära uppgifter samt att man fram tills nyligen inte låtit statens förmåga att hantera kriser och ytterst ett väpnat angrepp vara dimensionerande. Vår slutsats är för att uppnå bästa möjliga operativa förmåga för staten att kunna hantera framtida kriser, och ytterst ett väpnat angrepp, så är en integrering av Kustbevakningen och Marinen i en och samma myndighet den bästa lösningen. / Along the changes in the security situation in the world, questions about the government's ability to face crisis and acts of war have risen. An official report of the Swedish Government has suggested that an integration of the Coast Guard and the Navy into a consolidated maritime defence force is needed in the future. The aim of governmental policy has despite this been on focusing on cooperation despite difficulties regarding the relationship between the Navy and the Coast Guard in cooperating. This study aims to analyze why Sweden has chosen to increase cooperation between the two authorities. The study is a qualitative case study in which WPR-approach is used to analyze the official government report supplemented by an interview with a ministry of defence official. The theoretical basis is the research of Sundelius et al consisting of theories regarding Swedish national crisis management. In summary - no political will exists regarding consolidation. It stems from a general unwillingness in mixing civilian and military tasks and that up until recently the government's ability to handle crisis, and ultimately war, was not the dimensioning aim. The conclusion is that in order to achieve the optimal ability for the government in handling future crisis and full war, an integration of the Coast Guard and Navy into one authority is the best solution.
106

Estudo da aplicabilidade do instituto do perdão tácito aos empregados da Administração Pública

Serrano, Mariana Salinas 15 March 2016 (has links)
Made available in DSpace on 2016-04-26T20:24:23Z (GMT). No. of bitstreams: 1 Mariana Salinas Serrano.pdf: 1305825 bytes, checksum: 90634f177e48cb87681db090ed04a379 (MD5) Previous issue date: 2016-03-15 / Even though the hiring process of employees (registered according to the Consolidation of the Labor Law) by the Public Administration may look simple at a glance, the employment relationships that are established are permeated with cumbersome questions when checked against the interface of Labor Law and Administrative Law. The present work aims to raise the main issues originated from applying the regime of the Consolidated Labor Laws to public employees (denomination now elected, as will be justified, the employees the Public Administration registeres according to the Consolidation of the Labor Law), considering, on one hand, the unavailability and inalienability of public interest, a guiding principle of the Administrative Law; and, on the other hand, the unavailability and inalienability of worker rights. The analysis of this dilemma will be conducted with a focus on studying the applicability of the institute of tacit pardon to public employees, which effectively challenges the juxtaposition of the legal-labor and legaladministrative regimes when verifying if the Government is able to abstain from penalizing an employee who committed a faulty act punishable with dismissal on a just cause basis and, also, if the legal system legitimizes this omission to be considered a pardonº / Embora à primeira vista possa parecer simples a compreensão do regime de contratação de empregados celetistas pela Administração Pública, as relações de trabalho que se estabelecem são permeadas por questões embaraçosas, diante da interface entre o Direito do Trabalho e o Direito Administrativo. Objetivamos com o presente estudo perfazer levantamento das principais problemáticas advindas da aplicação do regime da Consolidação das Leis do Trabalho aos empregados públicos (denominação ora eleita, conforme será justificado no decorrer do trabalho, aos empregados celetistas da Administração Pública), tendo em vista, de um lado, a indisponibilidade do interesse público, princípio norteador do Direito Administrativo; e, de outro lado, a indisponibilidade dos direitos do trabalhador. A análise desse dilema será feita com enfoque no estudo da aplicabilidade do instituto do perdão tácito aos empregados públicos, que efetivamente coloca em cheque a justaposição dos regimes jurídico-trabalhista e jurídico-administrativo, ao verificar se pode o Estado, deixar de punir empregado que tenha cometido ato faltoso apenado por justa causa e, ainda, se o ordenamento jurídico legitima que essa omissão seja considerada perdão à falta cometida, pelo silêncio
107

O Princípio Democrático, o dinamismo social e as cláusulas pétreas

Queiroz, José Guilherme Carneiro 23 October 2006 (has links)
Made available in DSpace on 2016-04-26T20:25:06Z (GMT). No. of bitstreams: 1 DIR - Jose Guilherme C Queiroz.pdf: 680337 bytes, checksum: 0b6931537adb71e1e1ba5755de5a1366 (MD5) Previous issue date: 2006-10-23 / The present monograph has as its motive the critical analysis of coexistence between consolidated clauses and democratic constitutional systems, verifying the evident paradox there is in the adoption done by the originary constituent Power, of provisions that disables changes before the democratic principle, which presupposes popular participation. We start this thesis with the study of the Constitution, verifying the reasons that motivate the presence of consolidated clauses in constitutional democratic systems, moving to the analysis of the constitutional immutability phenomena, brought by the current existence of intangibility clauses. In the same chapter, there is the approach of the relation between time and fundamental rights, leading to the analysis of the power which funds the State. The creation of the Constituent Power and of its structural bases, are then verified in order to the understanding of the inaugural activity of the States and generator of Constitutions. From this point on, it is possible with more resources, to analyze the existing relation between future generations and the first mark of State which will coexist inserted in this constitutional system) and the material limits. We, then, assess the topic related to democracy, tracking solid subsidies for an approach that allows the continuity of thought that guides the entire current dissertation. this way, this study evolves to the final analysis of the existing dilemma between consolidated clauses and democracy. Last of all, alternatives are presented for the guarantee of the protection of the Constitution, as well as for the flexibility of material limits of the Constitution / A presente monografia tem por móvel a análise crítica do convívio existente entre as cláusulas pétreas e os regimes constitucionais democráticos, verificando o claro paradoxo que há na adoção, feita pelo Poder constituinte originário, de dispositivos que impossibilitam a mudança diante do princípio democrático, o qual, por sua vez, pressupõe a participação popular. Iniciamos esta dissertação pelo estudo da Constituição, verificando os motivos que dão azo à presença das cláusulas pétreas nos sistemas constitucionais democráticos, passando, então, para a análise do fenômeno da imutabilidade constitucional, trazido pela presença das cláusulas de intangibilidade. No mesmo capítulo, ainda, é tratada a relação entre o tempo e os direitos fundamentais, passando, após, à análise do poder que funda o Estado. O surgimento do Poder Constituinte e suas bases estruturais, então, são verificados de modo a compreender-se a atividade inaugural dos Estados e criadora das Constituições. A partir deste ponto, é possível, com maior instrumental, analisar a relação existente entre as gerações futuras ao marco inicial do Estado (as quais conviverão inseridas neste sistema constitucional) e os limites materiais. Ingressamos, posteriormente, no tópico relativo à democracia, buscando, nesta trilha, subsídios sólidos para a continuidade do pensar que norteia toda a presente dissertação. Neste passo, desenvolve-se este estudo até a análise final do dilema existente entre as cláusulas pétreas e a democracia. Por fim, são apresentadas alternativas para a garantia de proteção da Constituição, bem como para a flexibilização dos limites materiais da Constituição
108

Uma contribui????o ao estudo da comparabilidade de demonstra????es cont??beis consolidadas : uma an??lise cr??tica atrav??s da utiliza????o de indicadores financeiros

Lima, Laurimar Veloso 27 April 2005 (has links)
Made available in DSpace on 2015-12-04T11:45:17Z (GMT). No. of bitstreams: 1 Laurimar_Veloso_Lima.pdf: 983919 bytes, checksum: 1a7d57e7d11895081f21c0851218fcc7 (MD5) Previous issue date: 2005-04-27 / This study has the objective to elaborate a critical analysis of the process of consolidation of the financial statements when the results of these are used for comparability purposes. Through an exploratory research, with examples analysis of accounting statements from 3 (three) business groups, it tries to evaluate the adaptation of these statements for comparative purposes and the capacity of these in predicting future tendencies, when analyzed separately. Understands that in spite of the consolidation of the accounting financial statements had represented a progress in the accounting science, of the legal demand and of the recognition of most of the doctrinaires of the value of the consolidated information the use of these statements possesses limitations and they are not exempt of critics. Significant variations in the results of controlled companies can commit the analysis of the consolidated statements or financial conditions of controlled company can be hidden in the consolidated results, in such a way that for a correct analysis of the group in subject, to analyse individual demonstrations is the best alternative. For development of the study it is done necessary, initially, to approach the methodology for evaluation of permanent investments in other companies and the procedures and techniques for the consolidation of the financial statements in Brazil. The methodology to be used will be exploratory research, through the techniques of bibliographical research, of documental research, demonstration and examples analysis. / Este estudo tem por objetivo elaborar uma an??lise cr??tica do processo de consolida????o dos demonstrativos financeiros quando os resultados destes s??o utilizados para fins de comparabilidade. Por meio de uma pesquisa explorat??ria, juntamente com a an??lise de exemplos de demonstra????es cont??beis de 3 (tr??s) grupos empresariais, procurou-se avaliar a adequa????o desses demonstrativos para fins comparativos e a capacidade para prognosticar tend??ncias futuras, quando analisados isoladamente. Entendeu-se que, apesar de a consolida????o das demonstra????es cont??beis ter representado um avan??o na ci??ncia cont??bil, da exig??ncia legal e do reconhecimento da maioria dos doutrinadores do valor das informa????es consolidadas, a utiliza????o desses demonstrativos possuem limita????es e n??o est?? isenta de cr??ticas. Varia????es significativas nos resultados das controladas podem comprometer a an??lise dos demonstrativos consolidados ou condi????es financeiras de controladas podem ser encobertas nos resultados consolidados, de tal forma que, para uma correta an??lise do grupo em quest??o, analisar demonstra????es individuais foi a melhor alternativa. Para o desenvolvimento do estudo foi necess??rio, inicialmente, abordar a metodologia para avalia????o de investimentos permanentes em outras sociedades e os procedimentos e t??cnicas para a consolida????o dos demonstrativos financeiros no Brasil. A metodologia empregada foi a pesquisa explorat??ria, por meio das t??cnicas da pesquisa bibliogr??fica, da pesquisa documental e da apresenta????o e an??lise de casos pr??ticos.
109

Estudo experimental do comportamento tensão-deformação de uma argila adensada unidirecionalmente / A experimental study of the stress-strain behavior of a one-dimensionally consolidated clay

Stancati, Gene 05 February 1991 (has links)
O trabalho é um estudo experimental do comportamento tensão-deformação, em argila adensada unidirecionalmente, após mistura com água. Para sua execução, foram desenvolvidos equipamentos para adensamento de grandes quantidades de Lama, e medidores eletrônicos específicos para deformações volumétricas e radiais, usados em ensaios de compressão triaxial. O modelo da teoria clássica elasto-linear, para solos com comportamento anisotrópico é utilizado, após desenvolvimento algébrico, na obtenção dos parâmetros da argila. Nos cálculos, são aplicados processos estatísticos de regressões polinomiais. São analisadas as correlações dos parâmetros elásticos iso e anisotrópicos (Módulos de Elasticidade, Coeficientes de Poisson e Módulos de Elasticidade Transversal), com as tensões confinantes dos ensaios triaxiais, e com os Índices de pré-adensamento OCR das Lamas. / This work is an experimental study of the stress-strain behavior on clay one-dimensionally consolidated, after mixing with water. A consolidation equipment designed for great mass of mud and specific electronic apparatus for volumetric and lateral displacements on the triaxial tests were developed for this study. The classical theory of elasto-linear model for anysotropic soils is used, after algebraic manipulation, to obtain clay parameters. Multiple regressions are used for variables computations. Iso and anysotropic elastic parameters (Young modulus, Poisson ratio and shear modulus) are correlated with the confinant stresses and the over-consolidation-ratios (OCR).
110

Monitoring des propriétés acoustiques et sismiques en milieu non consolidé / Monitoring of acoustic and seismic properties in unconsolidated environment

Jaafar, Omar 15 December 2014 (has links)
Mon sujet de thèse concerne les propriétés acoustiques et sismiques des formations non consolidées. Ce sujet est très mal connu, depuis la surface d'une part parce que la physique des milieux non consolidés est encore mal connue, et en forage d'autre part parce que ces milieux ne sont pas stables mécaniquement. Toute mesure en forage demande donc la pose d'un tubage et la réalisation des mesures à travers ce tubage. Dans le cadre de ma thèse, on appliquera premièrement ces mesures aux domaines du stockage de CO2 dans les formations géologiques, et ensuite à celui des glissements de terrains. Dans ce cadre, des mesures ont été réalisées sur les sites de Maguelone et de Svelvik pour le stockage géologique du CO2, et de Lodève pour les glissements de terrain.Le site expérimental Maguelone (France) a fait l'objet de la surveillance géophysique de la surface et en forages pendant les expériences d'injection de gaz dans un réservoir souterrain de roches clastiques peu profonde. En particulier, les profils sismiques verticaux (PSV) et les logs Sonique (derrière un tubage PVC) ont été enregistrés dans deux puits situés à quelques mètres du puits d'injection, avant, pendant et après une série d'injections de gaz. Les premieres arrivées pour les PSV ont été obtenues par le pointage (picking), et interprétées en termes de modèles de vitesses sismiques. Les données Sonique, après les avoir comparées avec les autres mesures pétrophysiques et géophysiques, ont été traitées et analysées en termes de vitesses et amplitudes. Avant l'injection, la comparaison des vitesses sismiques et d'amplitude entre les expériences dans un seul puits (MAG1), met en évidence l'impact de l'injection de gaz sur les propriétés élastiques des sédiments détritiques poreux au niveau du site d'injection, ce qui indique une augmentation de la saturation en gaz en face des couches sableuses et de couches de gravier. En tout, time-lapse VSP et les sonic logs, fournissent un moyen pour détecter et surveiller l'injection et le stockage de gaz dans des réservoirs géologiques, conduisant à une vue sur la dynamique du sous-sol au cours du temps. L'objectif du projet de CO2FieldLab (Svelvik Site_ Norvège) était de démontrer que les méthodes de surveillances adéquates peuvent être déployées pour documenter les risques de fuites de CO2 dans des réservoirs souterrains. Pour ce faire, une expérience d'injection peu profonde dans le sédiment perméable a été conçu et réalisé à Svelvik (Norvège) en Septembre 2011. L'objectif était de produire une fuite de CO2 afin d'évaluer la sensibilité relative de plusieurs outils de surveillance des émissions de CO2 géochimiques et géophysiques. Cette étude a mis en évidence le potentiel des méthodes acoustiques pour la surveillance et la détection de faible profondeur le stockage du CO2 et de la migration. Dans chacun des sites de l'étude, les séries de techniques ont été utilisées avec succès pour monitorage le stockage du CO2 et de la migration dans les réservoirs peu profonds, ces techniques se combinent les approches géophysiques et géochimiques. Sur le site de Lodève, mon travail s'est focalisé sur l'analyse de diagraphies et d'images ultrasoniques de parois obtenues sur seulement 20 mètres en trou nu dans la zone de déformation d'un glissement de terrain actif dans cette région. Des profils sismiques de surface ont également été enregistrés. Par contre, du fait de l'instabilité mécanique du forage, une légère déformation élastique ovale du forage a été mise en évidence aussi bien sur les images en distance qu'en amplitude. En utilisant la méthodologie utilisée traditionnellement pour l'analyse de déformations cassantes en forage (appelées "breakouts"), on note que la direction d'ovalisation correspond à la direction de plus grande pente du flanc de colline affectée par le glissement traversé par le forage entre 60 et 70 mètres, dans l'intervalle où les images ont été enregistrées. / The objective of My thesis concerns the acoustic and seismic properties of unconsolidated formations. This topic is poorly known, from the surface -of one hand- because the physical of unconsolidated environments is still poorly understood, and in the well on the other hand where these environments are not mechanically stable. Therefore any downhole measure requests the installation of a casing and taking measurements through this casing. In my thesis, these measurements were used for the geological storage of CO2, and then in the landslide. In this context, measures have been carried out on sites Maguelone and Svelvik for the geological storage of CO2, and in the Lodeve site for landslides.The Maguelone experimental site (France) has been the subject of surface and downhole geophysical monitoring of gas injection experiments in a shallow subsurface clastic reservoir. In particular, vertical seismic profiles (VSP) and downhole SONIC logs (through PVC liners) were recorded in two holes located within meters of the gas injection hole, before, during and after a series of gas injections. VSP first-arrival times were obtained by picking, and interpreted in terms of seismic velocity models. The sonic data, once compared to other logs and core petrophysical measurements, have been processed and analyzed in terms of velocities and amplitudes. Before injection. The comparison of seismic velocities and amplitude between experiments for a single hole brings out the impact of gas injection on the elastic properties of the porous clastic sediments at the injection site, suggesting an increase in gas saturation in front of the sandy and gravel-rich layers. . In all, time-lapse VSP and sonic logging through PVC provide a means to detect and monitor gas injection and storage in geological reservoirs, leading to a view on subsurface dynamics over time. The objective of the CO2FieldLab project (Svelvik site_ Norway) was to demonstrate that adequate monitoring methods can be deployed to document potential leaks of CO2 from subsurface reservoirs. For this, a shallow injection experiment through permeable sediment was designed and conducted at Svelvik (Norway) in September 2011. The goal was to produce a CO2 leak in order to assess the relative sensitivity of several geochemical and geophysical CO2 monitoring tools. This study highlighted the potential of acoustic methods for shallow monitoring and detecting of the CO2 storage and migration. In each of the study sites, the series of techniques have been successfully used to monitor CO2 storage and migration in the shallow reservoirs, these techniques combine geophysical and geochemical approaches On the Lodeve site, my work focused on the well logging analyzes especially the ultrasonic images obtained 20 meter only of the hole in the deformation zone un active landslide in the region. A slight elastic deformation oval of the hole was demonstrated both the distance and amplitude images. Using the methodology traditionally used for the analysis of the breakouts, we have noted that the ovalisation direction corresponds to the direction of slope of the hillside affected by slipping, traversed by the well between 60 and 70 meters of depth, the interval were the image ultrasonic recorded.

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