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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.
591

Dynamique des masses d'eaux côtières libanaises soumises à l'impact d'un fleuve. / Dynamics of Lebanese coastal waters subjected to the impact of a river

Ghsoub, Myriam 27 September 2019 (has links)
Le but principal de cette étude est de comprendre le fonctionnement de la zone interface, continuum terre-mer au Liban. Suite à l’anthropisation spécifiquement la construction des barrages, les apports du fleuve vers la mer en termes de quantité et qualité, sont modifiés de nos jours. Le fleuve Ibrahim, ayant le débit le plus important parmi les fleuves libanais, interrompu par trois barrages, a été choisi comme étude de cas représentant les fleuves côtiers libanais. Les différents paramètres retenus ont permis de dégager des résultats intéressants. Au niveau de l’eau de surface marine le panache fluvial est décelé par l’étude des paramètres hydrologiques des masses d’eaux superficielles. Les résultats montrent aussi que l’apport fluviatile est le contributeur principal en nutriments au niveau de la région côtière durant la saison humide, élucidé par les teneurs en nitrates et silice dissoute. D’autre part, le transfert des particules de la zone côtière vers le large, à travers la pente continentale, se fait par l’intermédiaire de couches néphéloïdes.L’origine des sédiments et de leurs constituants est mise en relief en analysant plusieurs paramètres sédimentaires. La combinaison des paramètres granulométriques et géochimiques organiques et inorganiques et l’application des tests statistiques a permis de distinguer entre deux environnements de dépôt. (1) Les environnements littoraux (≤ 30 m) ou zone de « bypass » où le sable fin et la matière organique autochtone dominent. (2) Les environnements profonds (≥ 60 m) ou zones de dépôts où la fraction fine et la matière organique allochtone dominent.Sur l’ensemble du suivi l’état chimique de l’eau du fleuve au niveau des deux stations échantillonnées, déduit des teneurs en nutriments et macrofaune benthique, est considéré comme bon à très bon d’après les normes internationales Finalement, l’analyse des éléments traces métalliques confirme la faible contribution anthropique dans les stations marines et fluviatiles échantillonnées malgré la densité de population croissante au niveau de la région côtière Libanaise. / The main purpose of this study is to understand the functioning of the coastal zone, land-sea continuum in Lebanon. Following the construction of dams, the contributions of the river towards the sea in terms of quantity and quality, are modified nowadays. The Ibrahim river, having the highest flow among the Lebanese rivers, interrupted by three dams, was chosen as a case study representing the Lebanese coastal rivers. The various parameters retained made it possible to obtain interesting results. At sea surface water level, the river plume is detected by studying the hydrological parameters of surface water.The results also show that the river is the main nutrient contributor in the coastal region during the wet season, elucidated by the nitrate and dissolved silica contents. On the other hand, the transfer of particles from the coastal zone to the open sea, across the continental slope, takes place through the nepheloid layers.The origin of sediments and their constituents is highlighted by analyzing several sediment parameters. The combination of organic and inorganic particle size and geochemical parameters and the application of statistical tests made it possible to distinguish between two deposition environments. (1) Coastal environments (≤ 30 m) or “bypass” area where fine sand and autochtonous organic matter dominate. (2) Deep environments (≥ 60 m) or deposit areas where the fine fraction and allochthonous organic matter dominate.The ecological state of the river water at the two sampled stations, deduced from the contents of nutrients and benthic macrofauna, is considered good to very good according to international standards. Finally, the analysis of metallic trace elements confirms the low anthropogenic contribution in the marine and river stations despite the increasing density of the population in the Lebanese coastal region.
592

Patterning of the embryonic vertebrate Brain in Response to Fibroblast Growth Factor Signaling

Raible, Florian 27 June 2003 (has links)
The term "pattern formation" refers to the process by which order unfolds in development. The present thesis deals with a particular aspect of molecular pattern formation during vertebrate embryogenesis. The model system in the focus of this study is the zebrafish, Danio rerio. In the early developmental phases of the zebrafish, Fibroblast growth factors (Fgfs) are involved in the molecular patterning of various tissues, including two regions of the brain, the forebrain and the midbrain-hindbrain region, affecting cellular processes as diverse as cell proliferation, differentiation, and axonal targeting. The goal of this study was to better understand the mechanisms by which Fgf signaling regulates pattern formation and embryogenesis. I addressed this question on several levels, investigating the extent of intracellular signaling (MAPK activation) relative to sources of Fgf expression, and the transcriptional responses of cells to Fgf signaling during embryogenesis. By a macroarray analysis, I identified putative transcriptional targets of Fgf signaling in late gastrulation, providing a set of molecules that are likely to act as functional players in relaying the patterning information encoded by Fgf signals. Among those are the secreted signaling molecules Chordin and Wnt8, as well as Isthmin, a novel secreted molecule that I found capable to interfere with anterior embryonic patterning. In addition, I identified two ETS domain transcription factors, Erm and Pea3, which constitute bona fide integrators of FgfR signaling. By gain- and loss-of-function studies, I demonstrate that transcript levels of erm and pea3 are tightly regulated by Fgf signaling. Detailed analysis of the expression patterns of erm and pea3 along with other Fgf target genes also provides evidence for a differential read-out of Fgf concentration in the embryo, consistent with a role of Fgf as a vertebrate morphogen. The discovery of novel molecular components downstream of Fgf receptor activity paves a way to characterize previously unknown or underestimated developmental roles of Fgfs in the molecular patterning of the forebrain, the eye and parts of the neural crest.
593

Influencer-marketing på sociala medier : En studie om relationen mellan företag och konsumenter genom Influencer-marketing / Influencer-marketing on Social Media : A study on the relationship between companies and consumers through Influencer-marketing

Björklund, Filip, Svensson, Sofia January 2023 (has links)
Under det senaste decenniet har digitaliseringen satt fart och utvecklat medielandskapet vilket resulterat i att sociala medier blivit ett av de främsta verktygen att tillämpa vid marknadsföring. Vidare har det utvecklats diverse verktyg att tillämpa på sociala medier för att driva sin marknadsföring framåt. Den mest använda sociala plattformen var Facebook år 2020. Därefter kom Instagram och Youtube där båda hade en användningsgrad på omkring 60% vilket är en siffra som ständigt ökar. Denna studie har för avsikt att undersöka om Influencer-marketing i sociala medier är en effektiv metod för företag att nå sin målgrupp på den svenska modemarknaden. Studien syftar till att påvisa avgörande faktorer för om strategin är värd att investera i eller inte. Målet är även att undersöka hur företagen resonerar kring möjligheter och risker med att arbeta med Influencer-marketing. Undersökningen grundar sig i en metodkombination som utgår från en kvantitativ enkät med klusterurval och fyra semistrukturerade, kvalitativa intervjuer med företag. Fyra företag deltog i undersökningen varav två tillämpar Influencer-marketing och två eliminerar metoden. Den kvantitativa enkäten resulterade i 131 svar från privatpersoner som dagligen exponeras av Influencer-marketing via sociala medier. Resultatet från undersökningen visade på att Instagram och Facebook är de främsta plattformarna för organisationer att marknadsföra på. Resultatet påvisade även att Instagram och TikTok var de främsta plattformarna som respondenterna spenderar sin tid på. Vidare påvisade resultatet även att det finns delade meningar kring att tillämpa Influencer-marketing vilket bland annat beror på företag, produkter och målgrupp. Samtliga företag som intervjuats verkar inom samma bransch men har varierande marknadsföringsstrategier. / In the last decade, digitization has accelerated and developed the media landscape, resulting in social media becoming one of the main tools for marketing. The most used social platform in 2020 was Facebook, followed by Instagram and YouTube, both with a usage rate of around 60%, which is a number that is constantly increasing.  This study aims to investigate whether influencer marketing on social media is an effective method for reaching the target audience in the Swedish fashion market. The study aims to demonstrate decisive factors for whether the Influencer-marketing strategy is worth investing in or not. The goal is also to examine how companies reason about opportunities and risks when working with influencer marketing. The study is based on a method combination consisting of a quantitative survey with cluster sampling and four semi-structured, qualitative interviews with companies. The companies that participated in the study were two that apply influencer marketing and two that eliminate the method. All companies interviewed operate in the same industry but have varying marketing strategies. The quantitative survey resulted in 131 responses from individuals who are exposed to influencer marketing on social media.  The result of the study showed that Instagram and Facebook are the primary platforms for organizations to market on. The result also showed that Instagram and TikTok were the primary platforms that respondents spend their time on. Furthermore, the result also showed that there are divided opinions about applying influencer marketing, which among other things, depend on the company, products, and target audience.
594

Evolution des méthodes de gestion des risques dans les banques sous la réglementation de Bale III : une étude sur les stress tests macro-prudentiels en Europe / Evolution of risk management methods in banks under Basel III regulation : a study on macroprudential stress tests in Europe

Dhima, Julien 11 October 2019 (has links)
Notre thèse consiste à expliquer, en apportant quelques éléments théoriques, les imperfections des stress tests macro-prudentiels d’EBA/BCE, et de proposer une nouvelle méthodologie de leur application ainsi que deux stress tests spécifiques en complément. Nous montrons que les stress tests macro-prudentiels peuvent être non pertinents lorsque les deux hypothèses fondamentales du modèle de base de Gordy-Vasicek utilisé pour évaluer le capital réglementaire des banques en méthodes internes (IRB) dans le cadre du risque de crédit (portefeuille de crédit asymptotiquement granulaire et présence d’une seule source de risque systématique qui est la conjoncture macro-économique), ne sont pas respectées. Premièrement, ils existent des portefeuilles concentrés pour lesquels les macro-stress tests ne sont pas suffisants pour mesurer les pertes potentielles, voire inefficaces si ces portefeuilles impliquent des contreparties non cycliques. Deuxièmement, le risque systématique peut provenir de plusieurs sources ; le modèle actuel à un facteur empêche la répercussion propre des chocs « macro ».Nous proposons un stress test spécifique de crédit qui permet d’appréhender le risque spécifique de crédit d’un portefeuille concentré, et un stress test spécifique de liquidité qui permet de mesurer l’impact des chocs spécifiques de liquidité sur la solvabilité de la banque. Nous proposons aussi une généralisation multifactorielle de la fonction d’évaluation du capital réglementaire en IRB, qui permet d’appliquer les chocs des macro-stress tests sur chaque portefeuille sectoriel, en stressant de façon claire, précise et transparente les facteurs de risque systématique l’impactant. Cette méthodologie permet une répercussion propre de ces chocs sur la probabilité de défaut conditionnelle des contreparties de ces portefeuilles et donc une meilleure évaluation de la charge en capital de la banque. / Our thesis consists in explaining, by bringing some theoretical elements, the imperfections of EBA / BCE macro-prudential stress tests, and proposing a new methodology of their application as well as two specific stress tests in addition. We show that macro-prudential stress tests may be irrelevant when the two basic assumptions of the Gordy-Vasicek core model used to assess banks regulatory capital in internal methods (IRB) in the context of credit risk (asymptotically granular credit portfolio and presence of a single source of systematic risk which is the macroeconomic conjuncture), are not respected. Firstly, they exist concentrated portfolios for which macro-stress tests are not sufficient to measure potential losses or even ineffective in the case where these portfolios involve non-cyclical counterparties. Secondly, systematic risk can come from several sources; the actual one-factor model doesn’t allow a proper repercussion of the “macro” shocks. We propose a specific credit stress test which makes possible to apprehend the specific credit risk of a concentrated portfolio, as well as a specific liquidity stress test which makes possible to measure the impact of liquidity shocks on the bank’s solvency. We also propose a multifactorial generalization of the regulatory capital valuation model in IRB, which allows applying macro-stress tests shocks on each sectorial portfolio, stressing in a clear, precise and transparent way the systematic risk factors impacting it. This methodology allows a proper impact of these shocks on the conditional probability of default of the counterparties of these portfolios and therefore a better evaluation of the capital charge of the bank.
595

Evaluating an ecosystem management approach for improving water quality on the Holnicote Estate, Exmoor

Glendell, Miriam January 2013 (has links)
The European Water Framework Directive 2000 established a new emphasis for the management of freshwaters by setting ecologically-based water quality targets that are to be achieved through holistic, catchment-scale, ecosystem management. However, significant knowledge gaps exist in the understanding of the cumulative effectiveness of multiple mitigation measures on a number of pollutants at a catchment scale. This research contributes to improved understanding of the effectiveness of an ecosystem management approach to deliver catchment-scale water quality improvements on the National Trust Holnicote Estate on Exmoor, UK. This research is part of a larger multi-objective project funded by the UK Department for Environment, Food and Rural Affairs (Defra), to demonstrate the benefits of land use interventions for the management of flood risk. This thesis evaluates the effects of upland ditch blocking on physico-chemical and biological parameters of water quality in an upland Horner Water catchment one year after habitat restoration, and establishes a solid baseline for the monitoring of the effects of current and future land management changes in a lowland, intensively managed, agricultural Aller catchment. The spatial variability of soil physical and chemical properties (bulk density, total carbon (TN), nitrogen (TN), C:N ratio, δ15N, total phosphorus (TP), inorganic phosphorus (IP), organic phosphorus (OP)) and water quality determinands (suspended sediment (SS), dissolved organic carbon (DOC), total particulate carbon (TPC), total oxidised nitrogen (TON) and dissolved reactive phosphorus (DRP)) in the two study catchments with contrasting land use has been characterised and linked to the prevailing land use. Agricultural land use resulted in extensive homogenisation of soil properties. The spatial dependence of all soil properties, except for bulk density and δ15N, was stronger in the agricultural than the semi-natural catchment (nugget:sill ratio 0.10-0.42 in the Aller and 0.15-0.94 in Horner Water), while bulk density, TP, inorganic phosphorus (IP), organic phosphorus (OP), C:N ratio, δ15N and carbon storage showed a longer range of spatial auto-correlation in the agricultural catchment (2,807-3,191 m in the Aller and 545-2,599 m Horner Water). The central tendency (mean, median) of all soil properties, except for IP and δ15N, also differed significantly between the two catchments (P < 0.01). The observed extensive alteration of soil physical and chemical properties in the agricultural catchment is likely to have long-term implications for the restoration of ecosystem functioning and water quality management. The intensive land use seems to have resulted in an altered ‘catchment metabolism’, manifested in a proportionally greater total fluvial carbon (dissolved and particulate) export from the agricultural than the semi-natural catchment. The agricultural catchment supported significantly higher DOC concentrations (P < 0.05) and the quality of DOC differed markedly between the two study catchments. The prevalence of more humic, higher molecular weight compounds in the agricultural catchment and simpler, lower molecular weight compounds in the semi-natural catchment, indicated enhanced microbial turnover of fluvial DOC in the agricultural catchment as well as additional allochtonous terrestrial sources. During an eight month period for which a comparable continuous turbidity record was available, the estimated SS yields from the agricultural catchment (25.5-116.2 t km2) were higher than from the semi-natural catchment (21.7-57.8 t km2). Further, the agricultural catchment exported proportionally more TPC (0.51-2.59 kg mm-1) than the semi-natural catchment (0.36-0.97 kg mm-1) and a similar amount of DOC (0.26-0.52 kg mm-1 in the Aller and 0.24-0.32 kg mm-1 in Horner Water), when normalised by catchment area and total discharge, despite the lower total soil carbon pool, thus indicating an enhanced fluvial loss of sediment and carbon from the intensively managed catchment. Whilst detection of catchment-scale effects of mitigation measures typically requires high resolution, resource-intensive, long term data sets, this research has found that simple approaches can be effective in bridging the gap between fine scale ecosystem functioning and catchment-scale processes. Here, the new macro-invertebrate index PSI (Proportion of Sediment-sensitive Invertebrates) has been shown to be more closely related to a physical measure of sedimentation (% fine bed sediment cover) (P = 0.002) than existing non-pressure specific macro-invertebrate metrics such as the Lotic Index for Flow Evaluation (LIFE) and % Ephemeroptera, Plecoptera & Trichoptera abundance (% EPT) (P = 0.014). Further testing of PSI along a pronounced environmental gradient is recommended as PSI and % fine bed sediment cover have the potential to become a sensitive tool for the setting and monitoring of twin sedimentation targets. Upland ditch management has not had any discernible effect on water quality in the semi-natural upland catchment one year after restoration, which may be due to the short-term post-restoration monitoring period but may also reflect benign effects of large-scale earth moving works on this high quality environment. The conceptual understanding of catchment processes developed in this thesis suggests that cumulatively, the recently completed mitigation works in the lowland agricultural catchment will likely result in reduced sediment and nutrient input into the aquatic environment. However, further research is needed to build on this detailed baseline characterisation and inform the understanding of the effectiveness of combined mitigation measures to reduce the flux of multiple contaminants at the catchment scale.
596

Policy development and implementation in the post-liberalization era in Zambia (1990s and beyond): towards a participatory planning and economic management model

Mulungushi, James Shamilimo 03 1900 (has links)
This thesis investigates policy formulation and implementation processes in Zambia. A number of issues emerge with respect to the weaknesses of the system and how policy decisions worsened Zambia's economic performance instead of improving it. The Kaunda era policies of nationalization had an adverse impact on productivity of industries as well as affecting the resource flow from donors and business houses. On the other hand President Chiluba's reforms in the 1990s have had both positive and negative impacts on the people of Zambia. The rapid privatization and liberalization affected employment levels thereby worsening the poverty levels. Further, the liberalization brought in stiff competition from other countries forcing most manufacturing companies to close down. The policy environment based on the Bretton Woods Institutions seems not to be working as result of not taking into account the local Zambian situation. On the other hand, there were positive macroeconomic developments such as growth in GDP, lowering of inflation and stabilizing of exchange rates as from 1996. This has however not improved the living standards of the people. In Zambia, the shifts back and forth between strong and weak planning institutions have negatively affected policy development and implementation. There has been uncoordinated policy development; as a result, some policies in the major sectors are contradictory while in other cases policies are not linked to the resource envelope, making them un-implementable. Secondly, the institutional framework for policy development is not effective. There is generally lack of coordination among ministries, provinces and other stakeholders in planning, implementation and monitoring and evaluation of development programmes. This thesis urges that the improving planning capacities at the national, provincial and district levels should improve the processes of policy development and implementation in Zambia, which will in turn help to reduce poverty. Further, the districts should be the centre for the bottom-up process. In order to carryout this responsibility, efforts should be made to improve their capacities. As for the top-down process, the Sector Advisory Groups should continue to participate in the planning, monitoring and evaluation so as to contribute to policy formulation and implementation. These should be coordinated by the National Development Coordinating Committee (NDCC) through a Planning Bureau. / Development Studies / D. Litt. et Phil. (Development Studies)
597

A study of democratic transition in south Africa : democratic through compromise and institutional choice

Seo, Sang-Hyun 11 1900 (has links)
The focus of this study is on South Africa's transition to democracy. It is argued in this thesis, that an analysis of the transition to democracy in South Africa and the transformation of the con ict that prevailed in this divided society could generate new avenues for theorising about transitions to democracy in divided societies amidst con ict. The aim with this thesis is to contribute towards a more comprehensive understanding of the complex nature of the process of transition to democracy, and the relevant theory involved, particularly with regard to transitions in divided societies. One consequence of the deep divisions within South African society has been the increase in violence, which followed liberalisation. The transition to democracy in South Africa, as a result, was characterised by continuing and escalating violence. In South Africa, the authoritarian regime deteriorated mainly because of internal factors, but external factors also played an important role. The analysis of the transition has been guided by the hypothesis that the democratisation of South Africa was accomplished through a compromise that was negotiated between the major political actors and which re ected the intra-, as well as the inter-dynamics in the domains of, state - political society - civil society. Thus, the main theme of this thesis is, that in the analysis of the dynamics of the tran- sition to democracy in South Africa, a basic framework in which the domains of, state - political society - civil society, are the domains where structural variables (such as culture, economic development, class structures, increased education and the international environ- ment) and behavioural variables (such as major political actors, elite factions, organisations from civil society) interact. Thus, in the diachronic analysis of South Africa's transition, an interactive approach, that seeks to relate structural constraints to the shaping of contingent choice, is followed. At the same time, the institutional substitution of a new democratic political dispensation is examined. In conclusion, democracies are complex phenomena, and they are caused by many di er- ent forces and synthesizing the relevant theoretical approaches to political change provides a more cogent and comprehensive explanation of democratic transition in South Africa. / (D. Litt. et Phil. (International Politics))
598

The meaning of the expression having died to sin in Romans 6:1-14

Mabelane, Kolena Solomon 11 1900 (has links)
The letter to the Romans conveys a message of God's love and how through his grace, he has prepared a way to liberate mankind from a life of sin to a life of righteousness. But the way the message is presented, this grace may easily be misunderstood as an encouragement for people to live in sin. In Chapter 6:1-14, a concise but detailed outline of the message of the epistle unfolds into two main sections, namely, the Indicative and the Imperative. Key statements in these sections are: 'How can we who have died to sin, continue to live in it?' (6:2), and 'Consider yourselves dead to sin and alive to God' (6:11). Failure to distinguish the separate meanings of these statements may lead to the conclusion that the pericope encourages libertinism. In outlining the:meaning of this expression, 'We have died to sin ... ', I hope to make a contribution for a better understanding of the message of this pericope, namely: The grace of God that enables believers to live a righteous / Biblical and Ancient Studies / M.A. (Theology)
599

Developing powers : modernization, economic development, and governance in Cold War Afghanistan

Nunan, Timothy Alexander January 2013 (has links)
In the last decade, scholars have recognized economic development and modernization as crucial themes in the history of the twentieth century and the ‘global Cold War.’ Yet while historians have written lucid histories of the role of the social sciences in American foreign policy in the Third World, far less is known on the Soviet Union’s ideological and material support during the same period for countries like Egypt, India, Ethiopia, Angola, or – most prominently – Afghanistan. This dissertation argues that the Soviet intervention in Afghanistan is best understood as the final and most costly of a series developmental interventions staged in that country during the latter half of the twentieth century by Afghans, Soviets, Americans, Germans and others. Cold War-era Afghanistan is best understood as a laboratory for ideas about the nation-state and the idea of a ‘national economy.’ One can best understand Afghanistan during that period less through a common but ahistorical ‘graveyard of empires’ narrative, and more in terms of the history of the social sciences, the state system in South and Central Asia, and the ideological changes in ideas about the state and the economy in 20th century economic thought. Four chapters explore this theme, looking at the history of the Soviet social sciences, developmental interventions in Afghanistan prior to 1978, a case study of Soviet advisors in eastern Afghanistan, and Soviet interventions to protect Afghan women. Making use of new materials from Soviet, German, and American archives, and dozens of interviews with former Soviet advisors, this dissertation makes a new and meaningful contribution to the historical literature on the Soviet Union, Central Asia, and international history.
600

Modélisation tridimensionnelle du comportement mécanique de la garniture de forage dans les puits à trajectoires complexes : application à la prédiction des frottements garniture-puits

Belaid, Abdessalem 25 September 2005 (has links) (PDF)
Réussir le forage d'un puits pétrolier le plus rapidement possible et à moindre coût est devenu un défi continu pour les professionnels du secteur. Pour relever ce défi, un bon dimensionnement des installations de forage s'impose. La meilleure prédiction des pertes liées aux frottements entre la garniture de forage et les parois du puits, notamment pour les puits à trajectoires fortement déviées, est un atout majeur pour ce dimensionnement. <br/>Les modèles usuels de prédiction des frottements montrent certaines insuffisances lorsque la trajectoire du puits se complexifie. Un nouveau modèle de calcul de frottements dans les puits de forage à trajectoires complexes a été développé et validé. Ce modèle utilise une méthode tridimensionnelle de reconstitution de la trajectoire intégrant à la fois la courbure et la torsion géométrique. Contrairement aux modèles classiques, qui supposent simplement que la garniture repose par gravité sur la paroi basse du trou de forage et qui négligent souvent la rigidité des tiges, le nouveau modèle rigide calcule la vraie déformée de la garniture de forage à l'intérieur du trou via un algorithme itératif de contact unilatéral. En outre, pour un gain important du temps de calcul, le modèle se base sur une intégration numérique directe des équations d'équilibre local sans avoir recours à la méthode des éléments finis.<br/>La comparaison avec un modèle couramment utilisé dans l'industrie de forage, appelé modèle LISSE, a été effectuée sur plusieurs puits réels et théoriques. Il ressort de cette comparaison que le nouveau modèle vient palier plusieurs faiblesses du modèle LISSE dans le cas des trajectoires à géométrie complexe (surestimation des zones de contacts et des forces de contact en présence de micro-tortuosité, non sensibilité au signe du gradient d'azimut en présence de fort gauchissement, hypothèse de contact sur la paroi basse du trou pas toujours vérifiée). Par ailleurs, la confrontation avec les mesures du terrain pour la plupart des puits à géométrie bidimensionnelle ou faiblement tridimensionnelle avec des faibles dog legs (ne dépassant pas 2 à 3°/30 m) fournit généralement des concordances entre les résultats des deux types de modèles et les valeurs mesurées. En revanche, en présence de tortuosités et dog legs locaux le nouveau modèle fournit une meilleure prédiction des pertes en frottement.

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