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Study of SRS Effect in On-Line Monitoring Fiber Transmission Systems and Broadband Erbium-Doped Fiber SourcesTsai, Szu-Chi 11 June 2003 (has links)
In the first part of this thesis, the stimulated Raman scattering (SRS) effect in optical time domain reflectometry (OTDR) on-line monitoring fiber transmission systems are investigated. We have investigated the distortion of baseband video picture arising from the 1.65 £gm OTDR-induced SRS effect in 1.55 £gm amplitude modulation with vestigial sideband (AM-VSB) cable television (CATV) transmission system. The baseband video-picture distortion in appearance with ¡§faintly white horizontal thins lines¡¨ on the TV picture is observed. The baseband video-picture distortion disappearing is demonstrated in the 1.31 £gm OTDR on-line monitoring 1.55
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Du monopole au marché : cas d'EDF une entreprise en mutation / From monopoly to the market : case of EDF, a company in mutationAït Abdeslam, Samira 30 June 2008 (has links)
La dérégulation du marché énergétique en Europe impulsée par la commission européenne pour introduire la concurrence a provoqué d’importants bouleversements au sein d’EDF (Electricité de France). En effet, longtemps géré sous monopole d’Etat, cet opérateur historique est désormais amené à changer de stratégie, de structure et de modes de management des compétences afin de réagir rapidement aux mutations économiques et aux risques qui en découlent. Dans ce travail de thèse, nous analysons ces transformations à partir de deux registres de recherches complémentaires en gestion : celui de la stratégie et celui de l’organisation. Le registre stratégique s'appuie sur une analyse "documentaire" à travers laquelle nous tentons d’analyser, d’une part, le poids du "jeu" institutionnel ainsi que le rôle du dirigeant dans l’orientation stratégique d’EDF et, d’autre part, d’analyser comment ces orientations se traduisent en changements structurels. Quant au registre organisationnel, celui-ci s'appuie sur deux analyses à la fois qualitative par entretiens semi-directifs et quantitative par questionnaire, à travers lesquelles nous tentons de démontrer, en nous centrant particulièrement sur le cas des structures commerciales d’EDF, que les capacités de changement de cette entreprise tendent à être conditionnées, au même titre que les entreprises privées, par un processus d’accumulation des compétences internes. Ces compétences dépendent de la capacité à valoriser au plan collectif les compétences individuelles, à savoir, de la qualité de l’apprentissage organisationnel. / The deregulation of the energy market in Europe, impelled by the European Commission to introduce competition, caused significant upheavals within EDF (Electricité De France). Indeed, managed a long time under the State monopoly, this French historical operator was brought to change its strategy, its structure and its competences management modes, in order to react quickly to the economic changes and their resulting risks. We analyzed in our thesis these transformations starting from two complementary registers: that of the strategy and that of the organization. The study of the strategic register, which was based on a "documentary" analysis through which we analyzed, on the one hand, the weight of the institutional "game" as well as the role of leaders in the EDF strategic orientation and, on the other hand, to analyze how these orientations were translated into structural changes. The study of the organisational register, which was based on two complementary analyses: a qualitative analysis, based on semi-directive talks, and quantitative analysis, based on questionnaires way. Theses analyses were particularly centred on the EDF commercial structures, which abilities of change tighten with being conditioned, as well as in private companies, by a process of internal competences accumulation. These competences depend on the capacity to promote to the collective plan individual competences, e.g. quality of organizational learning.
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Constraints on the nuclear energy density functional and new possible analytical forms / Contraintes sur la fonctionnelle de la densite d'energie nucleaire et nouvelles formes analytiques possiblesSadoudi, Jeremy 21 September 2011 (has links)
La méthode dite de la fonctionnelle de la densité d'énergie (EDF) est l'outil théorique de référence pour l'étude systématique de la structure des noyaux atomiques de masse A>20. La méthode EDF est formulée en deux étapes successives consistant à briser puis à restaurer les symétries du Hamiltonien nucléaire sous-jacent. La technique de restauration des symétries n'est cependant rigoureusement formulée que si la fonctionnelle d'énergie dérive explicitement d'une interaction effective, i.e. d'un pseudo-potentiel, ce qui constitue un cas particulier de la méthode EDF plus générale. Ainsi, et comme cela a été démontré récemment, l'utilisation des paramétrisations existantes des fonctionnelles d'énergie conduit à l'obtention de résultats non physiques. Le pouvoir prédictif limité des fonctionnelles d'énergie existantes et leur inocuité relative à la restauration des symétries, nécessitent aujourd'hui de repenser leur méthode de construction. La première partie de ce travail a été dédié à l'analyse approfondie du problème associé à la restauration de symétrie et à l'identification de pistes permettant de contraindre la forme analytique des fonctionnelles d'énergie ne dérivant pas d'un pseudo-potentiel indépendant du système. La seconde partie a consisté à développer un pseudo-potentiel rendant la restauration des symétries automatiquement bien définie. Les difficultés de ce travail ont résidé dans (i) l'identification de la complexité minimale du pseudo-potentiel nécessaire à l'obtention d'une fonctionnelle d'énergie assez flexible pour égaler, et si possible améliorer, les performances des paramétrisations existantes, (ii) la dérivation analytique de la fonctionnelle et des champs à un corps découlant de celle ci, (iii) l'implémentation de ces derniers dans les codes de calculs, et dans (iv) le développement d'un protocole d'ajustement des paramètres adapté à la nouvelle fonctionnelle d'énergie ainsi développée. Les premiers résultats obtenus ont permis de valider l'approche en démontrant la flexibilité suffisante du pseudo-potentiel au niveau des calculs réalisés sans restauration des symétries. / The theoretical tool of choice for the microscopic description of all medium- and heavy-mass nuclei is the Energy Density Functional (EDF) method. Such a method relies on the concept of spontaneous symmetry breaking and restoration. In that sense, it is intrinsically a two-step approach. However, the symmetry restoration procedure is only well-defined in the particular case where the energy functional derives from a pseudo-potential. Thereby and as it has been recently shown, existing parameterizations of the energy functional provides unphysical results. Such a problem as well as the lack of predictive power call for developing new families of functionals. The first part of the present work is devoted to a study of the symmetry restoration problem and to the identification of properties that could constrain the analytic form of energy functionals that do not derive from a pseudo-potential. The second part deals with the construction of an energy functional that derives from a pseudo potential. The difficulties of such work are (i) the identification of the minimal complexity of the pseudo-potential necessary to obtain an energy functional that is flexible enough to provide high-quality EDF parameterizations, (ii) the tedious analytical derivation of the functional and of the associated one-body fields, (iii) the implementation of the latter in existing codes, and (iv) the development of an efficient fitting procedure. Eventually, it seems possible to generate a parameterization that strictly derives from a pseudo-potential and that provides as good results as state-of-the-art (quasi) bilinear functionals.
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Small scale VTOL aircraft using only one lift-producing motor : A study of lift capacity for a Vertical Take-Off and Landing capable aircraft / Vertikal start- och landningsfarkost med vektoriserad dragkraft och enbart en lyftmotorMilenkovic, Daniel January 2023 (has links)
The usage of unmanned aerial vehicles in applications such as terrain mapping and surveillance is proliferating in the modern world. This project aims to investigate the feasibility, in terms of payload capacity and stability, of small scale winged aircraft that have the ability to lift and land vertically, while also being able to transition to normal forward flight using wings for primary lift. The prototype aircraft was built with the limitation of using only one lift-producing motor that would be responsible for both vertical take-off and landing, and the horizontal propulsion in forward flight. The prototype was built primarily using 3D-printed plastic with an electric ducted fan as the method of propulsion. Internal ducting was used to redirect airflow downwards, from the only propulsion source to achieve vertical lift at a standstill. The final iteration of the aircraft successfully performed multiple hovers over 30 seconds long but did not have wings to test a transition to forward flight. Lifting capacity was low but the concept proposed in this thesis holds promise for further development and optimization. / Användningen av obemannade luftfarkoster för tillämpningar såsom terrängkartläggning och övervakning ökar i den moderna världen. Detta projekt syftar till att undersöka lämpligheten, i termer av lastkapacitet och stabilitet, för småskaliga vingade luftfarkoster som har förmågan att lyfta och landa vertikalt, samtidigt som de kan övergå till normal framåtflygning med vingar för primär lyftkraft. Prototypen av luftfarkosten byggdes med begränsningen att endast en lyftproducerande motor skulle användas, som skulle vara ansvarig för både vertikal lyftning och horisontell framdrivning vid framåtflygning. Prototypen byggdes främst med 3D-utskrivna plastkomponenter med en elektrisk innesluten fläkt som källa för dragkraft. Interna luftkanaler användes för att omdirigera luftflödet nedåt, från den enda lyftproducerande motorn, för att uppnå vertikal lyftkraft vid ett stillastående. Den slutliga versionen av luftfarkosten utförde flera svävningar i över 30 sekunder, men farkosten hade inga vingar för att testa övergången till framåtflygning. Lastkapaciteten var låg, men konceptet som föreslogs i denna avhandling är lovande för vidare utveckling och optimering.
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L'educazione fisica e lo sport quali strumenti d'inclusione sociale e scolastica, per giovani disabili e studenti B.E.S. / Physical education and sport as educational tools in social and school inclusion for young disabled people and S.E.N studentsMilani, Melissa Angela <1963> 19 April 2016 (has links)
Il progetto è in sintonia con i nuovi scenari di ricerca, sia in ambito nazionale che internazionale, per l’inclusione e l’attiva partecipazione all’interno della società delle persone con disabilità e delle loro famiglie. Sebbene le molte problematiche ancora da superare, negli ultimi anni il tema dell’inclusione (scolastica e sociale) delle persone che presentano delle disabilità sta’ attraendo l'attenzione di settori sempre più ampi di popolazione, quanto guadagnando sempre più spazio all'interno dei momenti di discussione circa le future politiche sociali. La ricerca analizza gli stakeholder primari e secondari responsabili dei processi di inclusione sociale e scolastica dei giovani disabili, supponendo, lo sport e l’educazione fisica quale strumento facilitatore di possibili azioni e cambiamenti volti a facilitare la vita delle persone disabili. L'adozione di questo approccio è presentato come denominatore comune di pratiche innovative sociali che a supporto dei processi inclusivi consentono il passaggio da un modello medico assistenziale a un approccio dei diritti civili alla disabilità. La base teorica di questa ipotesi trova sostegno in molti principi di Integrazione Scolastica e l'obiettivo principale delle ipotesi di ricerca è sulla partecipazione ed emancipazione come strategie volte ad affrontare i problemi esistenti relativi alla inclusione. Le esperienze studiate rappresentano esempi di promozione dell’inclusione nei sistemi scolastici : contribuendo al dibattito sull’ “inclusive education”, sostenendo processi di inclusione sociale rivolti a tutti coloro che si trovano in situazione di svantaggio psico-fisico e sensoriale. Nella seconda parte l’analisi di alcuni studi in materia di approcci partecipativi nelle aree di interesse come esempio del miglioramento dell'inclusione, attraverso il coinvolgimento degli stakeholder dell’inclusione. Proseguendo nella ricerca si tenta di indagare sul livello di pregiudizio dei giovani all’interno di ambienti scolastici e sportivi, partendo da questioni ancora aperte. / The project is in tune with the new research scenarios, both nationally and internationally, for the inclusion and active participation in society of people with disabilities and their families. Although many problems still to be overcome, in recent years the issue of inclusion (educational and social) of people with disabilities is' attracting the attention of increasingly broad sectors of the population, since gaining more and more space inside opportunities for discussion about future social policies. The research analyzes the primary and secondary stakeholders responsible for the processes of social inclusion and education of young people with disabilities, assuming, sport and physical education as a facilitator instrument of possible actions and changes aimed at making life easier for disabled people. The adoption of this approach is presented as a common denominator of social innovative practices in support of inclusive processes allow the transition from a welfare approach to a medical model of civil rights to disability. The theoretical basis of this hypothesis finds support in many principles of Scholastic Integration and the main objective of the research hypothesis is on participation and empowerment as strategies to address existing problems relating to inclusion. The experiences studied are examples of inclusion promotion in school systems: contributing to the debate on ' "inclusive education", supporting processes of social inclusion aimed at all those who are in a state of psycho-physical and sensory handicap. In the second part of the analysis of several studies in the field of participatory approaches in the areas of interest as an example of improving the inclusion, through the involvement of stakeholder inclusion. Continuing research will try to investigate the level of injury for young people within school and sporting circles, starting from open questions.
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Confronto fra periodizzazione Tradizionale e a Blocchi per l’allenamento della forza in atleti maschi e partecipanti di genere femminile. / A comparison of Traditional and Block periodized strength training programs in male athletes and in women.Bartolomei, Sandro <1982> 14 April 2015 (has links)
La prima parte dello studio riguarda la descrizione dell’origine e delle caratteristiche che differenziano la periodizzazione tradizionale e quella a blocchi per l’allenamento della forza.
L’obiettivo della seconda parte del lavoro è stato quello di confrontare gli adattamento ormonali e prestativi ad un programma di allenamento della forza periodizzato secondo il modello tradizionale o secondo quello a blocchi in un campione di atleti di forza. Venticinque atleti maschi sono stati assegnati con procedura randomizzata al gruppo con programmazione tradizionale (TP) o a quello a blocchi (BP). Prelievi di saliva sono stati effettuati prima e dopo 6 diverse sedute di allenamento durante il programma al fine di rilevare i livelli di testosterone (T) e cortisolo (C). Le valutazioni dei parametri antropometrici e prestativi sono state effettuate prima e dopo le 15 settimane di allenamento previste. In nessuno dei due gruppi vi sono state variazioni significative nei livelli ormonali. I risultati indicano che il gruppo BP ha ottenuto incrementi superiori a quello TP riguardo alla forza massima (p = 0,040) ed alla potenza (p = 0,035) espressa alla panca piana.
Nella terza parte dello studio, la periodizzazione tradizionale e quella a blocchi sono state confrontate riguardo agli effetti sulla forza massima e sull’ipertrofia in donne allenate di livello amatoriale. Diciassette donne hanno partecipato all’esperimento allenandosi 3 volte a settimana per 10 settimane. I risultati dimostrano che entrambe le periodizzazioni hanno portato a miglioramenti significativi di forza e potenza; il gruppo TP ha tuttavia ottenuto incrementi superiori di forza massima (p = 0,039) e ipertrofia degli arti inferiori (p = 0,004). La periodizzazione tradizionale quindi si è dimostrata più efficace per aumentare la forza massima e la sezione muscolare della coscia in partecipanti di genere femminile. I risultati contrastanti nei due generi potrebbero essere legati a rapporti diversi fra processi anabolici e catabolici. / The first part of the study explored the origin and the fundamental characteristics of the traditional and the block periodization models for strength training.
The aim of the second part of the study was to compare the hormonal and strength responses to a block (BP) and a traditional (TP) periodized strength training programs in male athletes. Twenty-five experienced resistance trained males were randomly assigned to either a block (BP) or a traditional (TP) periodized resistance training program. Salivary samples were taken before and after six different workouts over the training period and measured for testosterone (T) and cortisol (C). Strength and power testing occurred before and after the 15-weeks training program. No differences were noted in the hormonal responses between BP and TP during any training cycle. Results indicated that BP appears to stimulate greater gains in bench press maximal strength (p = 0,040) and power (p = 0,035) compared to TP.
The third part of the study was a comparison of block (BP) and traditional periodization (TP) on maximal strength and hypertrophy of recreationally strength trained women. Seventeen women participated in the study and trained 3 days a week for 10 weeks. The results revealed that both BP and TP groups made significant increases in strength and power but improvements in lower body strength and hypertrophy were significantly greater in TP group compared to BP group (p = 0,039 and p = 0,004, respectively). Results indicate that traditional model is more effective than the block periodization model for increasing maximal strength and muscle size of the lower body in women. The conflicting data between TP –vs BP training methods in men and women may be related to a gender difference in anabolic/catabolic ratio.
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Aid Nothing More Than a Charity Bone Thrown : Have Past Failures prepared us for Future Success?Buhlin, Sofia January 2010 (has links)
<p><strong>Abstract</strong></p><p>This article investigates the complex issue of aid, and differs from other attempts at evaluating the outcomes and policies of aid since this evaluation is solely based on the policies of the donor countries. It investigates if, and how well, the world´s two greatest aid donors, The European Developmental Fund (EDF) and the United States Agency for International Development (USAID) responds to recent research and the need for change in this policy area in respect to Sub- Saharan African states. </p>
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Fonctionnelles d'energie non-empiriques pour la structure nucleaireRotival, Vincent 29 September 2008 (has links) (PDF)
La methode de la fonctionnelle de la densite d'energie (EDF) est un outil de choix pour l'etude de la structure nucleaire a basse energie, car elle permet des calculs de noyaux finis aussi bien pour des systemes stables connus experimentalement dont les proprietes sont reproduites avec une bonne precision, que pour des noyaux qui ne peuvent encore etre produits mais sont predits theoriquement. Dans la premiere partie de cette these, une nouvelle methode quantitative est introduite pour caracteriser l'existence et les proprietes des halos dans les noyaux moyens et lourds, ainsi que pour etudier l'impact des correlations d'appariement ou du choix de la fonctionnelle d'energie sur leur formation. Il apparait que la solidite de ces resultats est limitee par le faible pouvoir predictif des fonctionnelles utilisees jusqu'a present qui sont ajustees sur des donnees experimentales. Dans la seconde partie de ce memoire, nous entreprenons la construction de fonctionnelles non-empiriques qui reposent sur un nouveau paradigme pour les forces nucleon-nucleon dans le vide, a savoir les interactions low-momentum engendrees par l'application des methodes du groupe de renormalisation. Ces potentiels a coeur mou sont utilises comme point de depart d'une strategie a long terme faisant le lien entre les techniques modernes de resolution du probleme a N corps et les methodes EDF. Nous donnons ainsi des perspectives pour construire differentes realisations d'un modele non-empirique d'interaction incluant les effets de milieu a differents niveaux d'approximation et pouvant etre traite dans les codes dedies a la structure nucleaire. Dans ce memoire, la premiere etape de ce travail est initiee par l'ajustement d'une representation operatorielle des forces low-momentum dans le vide realise au moyen d'un algorithme parallele d'intelligence artificielle. Les premiers resultats mettent en valeur la possibilite d'incorporer la physique necessaire a la structure de basse energie dans ce vertex gaussien.
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Real-Time Ethernet Networks Simulation ModelPensawat, Taweewit January 2006 (has links)
<p>Real-time networks are traditionally built on proprietary standards, resulting in a interoperability issues between different real-time netork implementations and traditional data networks mainly used in back office operations.</p><p>Continuity and supplier independence are a cause of concern with current</p><p>proprietary real-time networks.</p><p>This project evaluates the capability of providing real-time traffic over</p><p>switched Ethernet with EDF scheduling algorithm implemented at both the</p><p>switch and the node. By using OMNET simulation tool at packet level, it</p><p>is shown that the EDF implementation in switched Ethernet can guarantee</p><p>real-time traffic over the network and at the same time supporting non real-time traffic.</p>
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Switched multi-hop EDF networks : The influence of offsets on real-time performanceSha, Maoxuan, Xie, Jun, Xu, Xiao Lin January 2011 (has links)
In computer science, real-time research is an interesting topic. Nowadays real-time applications are close to us in our daily life. Skype, MSN, satellite communication, automation car and Ethernet are all things related to the real-time field. Many of our computer systems are also real-time, such as RT-Linux, Windows CE. In other words, we live in a “real-time” world. However, not everyone knows much about its existence. Hence, we chose this thesis in order to take a knowledge journey in the real-time field. For an average reader, we hope to provide some basic knowledge about real-time. For a computer science student, we will try to provide a discussion on switched multi-hop network with offsets, and the influence of offsets on real-time network performance. We try to prove that offsets provide networks of high predictability and utilization because offsets adjust packet‟s sending time. A packet‟s sending time is the time when a sender/router starts to transmit a date packet. Packets are sent one after the other. Therefore, we need to lower the time interval between one packet and another. Hence, in our network model, network performance is more predictable and effective. There might be some things left to discuss in future, so we would like to receive any advice and also suggestions for future discussions.
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