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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.
371

La gestion des ressources humaines dans l'industrie de l'investissement institutionnel : le cas des analystes financiers français sell-side

Benchemam, Faycel 30 June 2009 (has links) (PDF)
Au cours de la précédente décennie et avant la crise financière de l'automne 2008, les marchés financiers internationaux ont connu un développement considérable et l'émergence d'une véritable industrie de l'investissement institutionnel. Au sein de cette industrie, les analystes financiers sell side employés par les sociétés de courtage apparaissent comme des acteurs majeurs, autour desquels se forment l'évaluation des sociétés cotées et les recommandations d'investissement à destination de leurs clients gestionnaires de fonds amenés à passer leurs ordres de bourse auprès de ces sociétés de courtage. La recherche présentée vise à identifier les modes de gestion des analystes financiers dans le champ de l'industrie de l'investissement institutionnel et l'influence qu'ils exercent sur les représentations, pratiques et productions des analystes. La première partie de cette thèse, après avoir étudié la construction du métier d'analyste et son contexte, met en débat les cadres de références théoriques et les disciplines qui s'impliquent dans l'analyse de la gestion du travail de quelques-uns des principaux acteurs de la finance, en général, et des analystes financiers en particulier. La seconde partie mobilise une approche contextualiste, interdisciplinaire et multi-méthodes au service d'une investigation empirique. Celle-ci met en relief le rôle du droit dans des dimensions coercitives et normatives très prégnantes, encourageant aussi bien la concurrence entre structures que l'homogénéisation et la standardisation de l'organisation du travail. Elle montre comment, sous l'effet de la concurrence des banques d'investissement anglo-saxonnes et de l'introduction d'un nouveau mode de financement de l'analyse financière par les volumes de courtage, les sociétés de « brokerage » ont adopté des stratégies de niche et intégré dans leurs configurations organisationnelles plutôt professionnelles de fortes dimensions mécanistes. Enfin, elle constate une uniformisation des modes de gestion des quatre principales sociétés de courtage françaises filiales de banques d'investissement. Les analystes français sont soumis à des modes de gestion qui privilégient clairement les dimensions marketing du métier qu'il s'agisse des modalités d'organisation du travail, des pratiques de recrutement, de communication interne, d'évaluation et de rémunération. Un des rôles essentiels assigné aux analystes consiste alors à accroitre les volumes de courtage ce qui les conduit à privilégier les activités aval de leur fonction. Mais cette dimension marketing qui caractérise la production des analystes doit être relativisée. En fonction de leur histoire professionnelle et des ressources qu'ils peuvent mobiliser, les analystes développent en effet des stratégies et des identités au travail différenciées.
372

Design and Characterisation of A SynchronousCo-Axuak Double Magnetron Sputtering System

Aijaz, Asim January 2009 (has links)
<p>High power impulse magnetron sputtering (HiPIMS) is a novel pulsed power technique. In HiPIMS, high power pulses are applied to the target for short duration with a low duty factor. It provides a high degree of ionization of the sputtered material (in some cases up to 90%) and a high plasma density (10<sup>19</sup> m<sup>-3</sup>) which results in densification of the grown films. Recently a large side-transport of the sputtered material has been discovered, meaning that the sputtered material is transported radially outwards, parallel to the cathode surface. In this research, we use this effect and study the side-ways deposition of thin films. We designed a new magnetron sputtering system, consisting of two opposing magnetrons with similar polarity. Ti films were grown on Si using the side-ways transport of the sputtered material. Scanning electron microscope was employed to investigate the microstructure of the grown films. Optical emission spectroscopy (OES) measurements were made for investigating the ionized fraction of the sputtered material while Langmuir probe measurements were made for evaluating the plasma parameters such as electron density. The conclusion is that the system works well for side-ways deposition and it can be useful for coating the interior of cylindrically shaped objects. It is a promising technique that should be used in industry.</p>
373

Valuation Relevance : The use of Information and Choice of Method in Equity Valuation

Flöstrand, Per January 2006 (has links)
<p>This thesis is concerned with exploring the equity market price discovery process, the translation and incorporation of new information into stock prices, by studying both what information is included in this process and which valuation methods are used to translate that information into a value.</p><p>The overarching research question posed in this thesis is: <i>How is equity valued?</i> The overarching question is broad and has been divided into the following sub questions:</p><p><i>What valuation methods do companies use when valuing takeover targets?</i></p><p><i>What valuation methods do sell-side analysts use when valuing equity?</i></p><p><i>What factors explain the variation in the use of valuation methods by sell-side analysts?</i></p><p><i>To what extent do sell-side analysts utilize non-financial information in their reports?</i></p><p>These questions are addressed in four separate essays. Findings of the thesis emphasized that valuation behavior is contextual to several specific circumstances. Findings showed that companies valuing takeover targets used sophisticated valuation methods to a higher extent than did sell-side analysts. Findings also showed systematic differences in the choice of valuation methods among sell-side analysts.</p><p>With regards to the use of non-financial information and information on Intellectual Capital this thesis showed that the context of the target firm dictates which information is relevant for predicting future performance, and hence is used by analysts. Additionally, the accessibility of information is an important factor affecting what information is used in the valuation process.</p><p>Understanding the valuation behavior of the different actors on the capital market is to understand the pricing process of the market, and as such the contribution of this thesis has been to shed more light on the cornerstone of market efficiency- the ability of market actors to identify and buy (sell) under priced (over priced) stocks.</p>
374

Towards security limits of embedded hardware devices : from practice to theory

Peeters, Eric 16 November 2006 (has links)
Mobile appliances and especially smart cards have found more and more applications in the past two decades. A little more than ten years ago, the security of those devices still only relied on mathematical complexity and computational infeasibility to force cryptographic systems. Unfortunately, during the execution of cryptographic algorithms, unintentional leakage may be observed. Indeed, the power consumption or the electromagnetic emanations of the device are correlated to the encryption/decryption process. Those unintended channels are called “sidechannel”. Our work was not targeted at the discovery of new “side-channel” sources but rather at a thorough investigation of two of them: the power consumption and the electromagnetic emanation in the near-field domain. In this respect, we dealt with three different aspects of the problem: 1. We carried out many experiments on small microcontrollers but also on FPGAs in order to provide an explanation on the sources and on the set up of an efficient measurement process. Moreover, we provide the first XY scanning pictures of the electromagnetic field radiated by a small microcontroller. 2. Obtaining several measures of the observed side-channel, how is it possible to statistically analyzed these observations? We detail here the different methods available and we introduce an enhancement in the Template Attack process with Principal Component Analysis. 3. Finally, on the basis of this experience, we tried to answer the following question: “Is it possible to provide a theoretical tool to evaluate secure implementations?” The idea was to follow the notion of “Physical Computer” introduced by Micali and Reyzin. In this respect, we provide here two metrics that we consider necessary to evaluate both the strength of the adversary and the information held in the leakage. Respectively we choose the average success rate and the Shannon's mutual information.
375

Protein side-chain placement: probabilistic inference and integer programming methods

Hong, Eun-Jong, Lozano-Pérez, Tomás 01 1900 (has links)
The prediction of energetically favorable side-chain conformations is a fundamental element in homology modeling of proteins and the design of novel protein sequences. The space of side-chain conformations can be approximated by a discrete space of probabilistically representative side-chain conformations (called rotamers). The problem is, then, to find a rotamer selection for each amino acid that minimizes a potential energy function. This is called the Global Minimum Energy Conformation (GMEC) problem. This problem is an NP-hard optimization problem. The Dead-End Elimination theorem together with the A* algorithm (DEE/A*) has been successfully applied to this problem. However, DEE fails to converge for some complex instances. In this paper, we explore two alternatives to DEE/A* in solving the GMEC problem. We use a probabilistic inference method, the max-product (MP) belief-propagation algorithm, to estimate (often exactly) the GMEC. We also investigate integer programming formulations to obtain the exact solution. There are known ILP formulations that can be directly applied to the GMEC problem. We review these formulations and compare their effectiveness using CPLEX optimizers. We also present preliminary work towards applying the branch-and-price approach to the GMEC problem. The preliminary results suggest that the max-product algorithm is very effective for the GMEC problem. Though the max-product algorithm is an approximate method, its speed and accuracy are comparable to those of DEE/A* in large side-chain placement problems and may be superior in sequence design. / Singapore-MIT Alliance (SMA)
376

Remote sensing analysis of natural oil and gas seeps on the continental slope of the northern Gulf of Mexico

De Beukelaer, Sophie Magdalena 15 November 2004 (has links)
Natural hydrocarbon seeps harbor distinctive geological, chemical, and biological features in the marine environment. This thesis verified remote sensing signatures of seeps using in-situ observation and repeated collections of satellite imagery. Bubble streams in the Gulf of Mexico water column from four natural seep sites on the upper continental slope were imaged by a side-scan sonar, which was operated from a submarine near the seafloor, and by acoustic profilers, which were operated from surface ships. These data were correlated with sea surface slicks imaged by Synthetic Aperture Radar (SAR) on the RADARSAT satellite. Comparing non-oily bubble streams from rapidly venting mud volcanoes with oily bubble streams from shallow deposits of gas hydrate showed that they produced notably different signatures. Non-oily bubbles produced high backscatter on the side-scan sonar records, but were difficult to detect with the acoustic profilers. Oily bubbles from hydrate deposits produced acoustic shadows on the side-scan sonar records. The oily bubbles generated clear signatures extending from the seafloor to the near surface on the acoustic profile records. RADARSAT SAR images verified the presence of surface oil slicks over the hydrate deposits, but not over the mud volcanoes. This indicates that SAR imagery will not be able to capture every oil and gas seep in a region because non-oily bubble streams do not create surface oil slicks. A total of 113 natural oily seep sources were identified based on surface slicks in eleven SAR images collected over the northern continental slope. A persistence analysis verified that SAR is a dependable tool for capturing oil slicks because 93.5% of the slick sources identified in the 2001 images were corroborated with slicks in the 2002 images. The sources ranged in depth from 100 to 2000 m and 79% of the sources were in 900 meters or greater of water. Seventy-six percent of the seep sources were associated with salt less than 1500 m below the seafloor and none of the sources were located in the bottom of salt withdrawal basins. Geographical Information Systems (GIS) proved to be a useful tool in these analyses.
377

Valuation Relevance : The use of Information and Choice of Method in Equity Valuation

Flöstrand, Per January 2006 (has links)
This thesis is concerned with exploring the equity market price discovery process, the translation and incorporation of new information into stock prices, by studying both what information is included in this process and which valuation methods are used to translate that information into a value. The overarching research question posed in this thesis is: How is equity valued? The overarching question is broad and has been divided into the following sub questions: What valuation methods do companies use when valuing takeover targets? What valuation methods do sell-side analysts use when valuing equity? What factors explain the variation in the use of valuation methods by sell-side analysts? To what extent do sell-side analysts utilize non-financial information in their reports? These questions are addressed in four separate essays. Findings of the thesis emphasized that valuation behavior is contextual to several specific circumstances. Findings showed that companies valuing takeover targets used sophisticated valuation methods to a higher extent than did sell-side analysts. Findings also showed systematic differences in the choice of valuation methods among sell-side analysts. With regards to the use of non-financial information and information on Intellectual Capital this thesis showed that the context of the target firm dictates which information is relevant for predicting future performance, and hence is used by analysts. Additionally, the accessibility of information is an important factor affecting what information is used in the valuation process. Understanding the valuation behavior of the different actors on the capital market is to understand the pricing process of the market, and as such the contribution of this thesis has been to shed more light on the cornerstone of market efficiency- the ability of market actors to identify and buy (sell) under priced (over priced) stocks.
378

Preparation and Electro-Optical Property of Novel Discotic Liquid Crystals and Poly(acrylamide) Dispersed LC with Application to Organic Solar Cells

Fan, To-cheng 08 August 2007 (has links)
In this thesis we synthesize two organic materials, one is discotic liquid crystal Acid-6, and the other is novel discotic liquid crystal polymer DLC-PAM. After demonstrating the molecular structures of Acid-6 and DLC-PAM by FT-MS, 1H-NMR and FT-IR, we use the two materials as photo-sensitized dyes for dye-sensitized solar cells(DSSCs) and manufacture two kinds of cells. We use polyacrylamide(PAM) as main chain of the novel discotic liquid crystal polymer DLC-PAM and graft the discotic liquid crystal monomer Acid-6 onto PAM by chemical synthesis. DLC-PAM belongs to side-chain liquid crystal polymer, and it can show the properties of it¡¦s discotic liquid crystal function. One of the properties is absorption of visible light. By observing the UV-Vis spectrum, we can realize the absorption band is located between 200 ~ 450 nm and confirm that it is able to be a photo-sensitized dye. Another property of discotic liquid crystal is the self-assembly ability, the moleculars can assemble into hexagonal columnar structure by themselves, and the property enable discotic liquid crystal to have better mobility. In this part, we can demonstrate DLC-PAM and Acid-6 really have hexagonal columnar structure by X-ray diffractmeter. After qualitative demonstrating and optical analysis, we use DLC-PAM and Acid-6 as photo-sensitized dyes for DSSCs and manufacture two kinds of cells successfully. The more photocurrent occur when the two DSSCs are woking. Besides, the two DSSCs have good performance on power conversion efficiency which can achieve 0.047 % for DLC-PAM and 0.364 % for Acid-6. Therefore, in this research we prove that DLC-PAM and Acid-6 are able to be photo-sensitized dyes for DSSCs and successfully demonstrate that using the two materials to manufacture DSSCs is feasible.
379

Hormone replacement therapy : benefits and adverse effects

Ödmark, Inga-Stina January 2004 (has links)
Background: Numerous studies have shown that estrogen replacement therapy (ERT) is an effective treatment for vasomotor symptoms, insomnia and vaginal dryness. Beneficial effects have also been shown on lipid patterns and on the incidence of osteoporotic fractures. As ERT increases the risk of endometrial adenocarcinoma, combinations with various progestogens have been developed in order to protect the endometrium. However, the addition of progestogens tends to reduce the beneficial effects of estrogens on mood, cognition and lipid metabolism. The added progestogen often causes side effects such as irritability and depression. There is evidence that the effect on wellbeing varies between women and with the type of progestogen used. Women who prefer to avoid withdrawal bleedings can be given continuous combined hormone replacement therapy (HRT). Unfortunately, irregular bleedings are common at the beginning of treatment and reduces compliance. Recently, several studies have reported an increased risk of breast cancer and venous thrombosis, and therefore long-term treatment with HRT for women without climacteric symptoms is no longer recommended. The ongoing debate has, for the time being, resulted in a recommendation that improving quality of life (QoL) by treatment of climacteric symptoms should be the only indication for prescribing HRT. Aims and methods: The aims of the study were to investigate bleeding patterns, changes in wellbeing at onset and during long-term treatment, and lipid and lipoprotein profiles with two different types of continuous combined HRT. In addition, women starting, and women switching from mainly sequential HRT were compared. The design was a randomised, double-blind, one year, prospective, multicentre study including 249 healthy postmenopausal women who were given continuous daily oral treatment with either combined 0.625mg conjugated estrogen (CE) and 5mg medroxyprogesterone acetate (MPA) or combined 2mg 17β - estradiol (E2) and 1mg norethisterone acetate (NETA). Bleedings, if any, were recorded daily throughout the study. The main outcome measures (changes in wellbeing and climacteric symptoms) consisted of daily ratings of 12 items on a validated symptom scale. Serum concentrations of lipids and lipoproteins were measured at baseline and after one year of treatment. Results and conclusions: The majority of drop-outs were confined to the first three months, and the main reasons were bleedings and/or decreased wellbeing. Drop-outs were three times more common in the E2/NETA group. During the first month, 67% of the women reported irregular bleedings. The number of bleeding days decreased on both treatments during the first four months. Treatment with CE/MPA resulted in less irregular bleedings and a shorter time to amenorrhoea compared to E2/NETA. As expected, "starters" experienced more sweats than "switchers" at the onset of treatment, but both groups improved significantly. Side effects such as breast tenderness, swelling, depression and irritability appeared during the first treatment week in both groups. The side effects of HRT appeared much more quickly than the benefits and were more frequent in women with a history of premenstrual syndrome (PMS). Breast tenderness was more common in the E2/NETA group throughout the whole study period. Apart from that, there were no differences between the two treatment regimens as regards effects on well-being at the end of the study. Lipoprotein(a) levels, an important risk factor for cardiovascular disease, decreased in both treatment groups. Triglyceride levels increased in women treated with CE/MPA, and levels of total cholesterol, high density lipoprotein and low density lipoprotein fell in the E2/NETA group. In conclusion, treatment with E2/NETA caused more bleeding problems than treatment with CE/MPA. CE/MPA was better tolerated than E2/NETA at the beginning of the study, but among the women remaining in the study there was no difference in QoL between the two treatment groups. HRT counselling should take into account that a history of PMS increases the likelihood of side effects and that these may precede any beneficial effects. Both treatments produced beneficial effects on lipid and lipoprotein levels, and neither of the regimens was superior in this respect.
380

Ice, wood and rocks : regulating elements in riverine ecosystems

Engström, Johanna January 2010 (has links)
Riparian ecosystems are of great importance in the landscape, connecting landscape elements longitudinally and laterally and often encompassing sharp environmental gradients in ecological processes and communities. They are influenced by fluvial disturbances such as flooding, erosion and sediment deposition, which create dynamic and spatially heterogeneous habitats that support a high diversity of species. Riverine ecosystems belong among the world’s most threatened systems. In rivers throughout the world, human alterations to fluvial disturbance regimes have resulted in degraded ecosystems and species loss. For example, in Sweden, watercourses of all sizes have been channelized to facilitate timber floating, but in the last 10–20 years the impacts in some of the affected rivers have been reduced by restoration actions. The objectives of this thesis are to evaluate how riverine ecosystems in general, with specific focus on riparian communities, are affected by (1) restoration of channelized reaches by boulder replacement, (2) ice formation, and (3) restoration of in-stream wood abundance in the stream channel. Objective (1) was assessed by quantifying the retention of plant propagules in channelized and restored stream reaches and by evaluating effects on riparian plant and bryophyte communities in disconnected and re-opened side channels. Retention of plant propagule mimics was highest at low flows and in sites where boulders and large wood had been replaced into the channel. Propagules are however unlikely to establish unless they can be further dispersed during subsequent spring high flows to higher riparian elevations suitable for establishment. Thus, immigration to new suitable sites may occur stepwise. Our study demonstrates that restoration of channel complexity through replacement of boulders and wood can enhance retention of plant propagules, but also highlights the importance of understanding how restoration effects vary with flow. We detected no differences in riparian diversity between re-opened and disconnected side channels, but we did observe significant differences in species composition of both vascular plant and bryophyte communities. Disconnected sites had more floodplain species, whereas restored sites had more species characteristic of upland forest. This suggests that the reopening of side channels resulted in increased water levels, resulting in new riparian zones developing in former upland areas, but that the characteristic floodplain communities have not had time to develop in response to the restored fluvial regime. Objective (2) was approached by evaluating the effect of both natural anchor ice formation and experimentally created ice in the riparian zone. Riparian plant species richness and evenness proved to be higher in plots affected by anchor ice. Plants with their over-wintering organs above the ice sheet suffered from the treatment but the overall species richness increased in ice-treated plots. Objective (3) was evaluated by studying wood recruitment and movement, channel hydraulics, propagule retention and fish abundance in streams restored with large wood. Only one stream experienced reduced velocities after large wood addition. The large size and reduced velocity were probably also the reasons why this stream proved to be the best one in trapping natural, drifting wood. Increased retention and decreased mechanical fragmentation in large wood sites will lead to decreased loss of detritus from the site and therefore higher availability of coarse particulate organic matter which can result in more species rich shredder communities. Our study did not show that the occurrence of large wood had an important role in controlling density or biomass of brown trout.

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