31 |
Mesure de glutamate cérébral chez l'homme et le petit animal par spectroscopie RMN in vivo, application à la maladie de ParkinsonKickler, Nils 30 June 2006 (has links) (PDF)
Ce travail a eu comme objectif de mettre en place des techniques de spectroscopie RMN du proton optimisées pour la détection du glutamate cérébral afin d'étudier des changements éventuels du métabolisme glutamatergique dans la maladie de Parkinson. En vue d'une application chez le patient, une approche de filtrage à double quanta et une méthode liée à la spectroscopie bi-dimensionnelle ont été évaluées à 3 Tesla sur un imageur corps entier. Une étude incluant dix patients atteints par la maladie de Parkinson idiopathique et dix volontaires sains a ensuite été réalisée, utilisant une méthode liée à la spectroscopie bi-dimensionelle et ciblant le noyau lenticulaire (putamen et globus pallidum). Aucun changement significatif du glutamate total (intra- et extracellulaire) n'a pu être mis en évidence comparant le patient sous traitement par levodopa (L-DOPA) ou ayant temporairement interrompu son traitement et le volontaire sain. Une tendance à la diminution de la creatine/phosphocreatine a été observée chez le patient. En vue d'une étude complémentaire sur le modèle animal, la méthode mise en œuvre chez le patient a été évaluée chez le rat à 7 Tesla. Une étude sur le rat traité par 6-hydroxydopamine (6-OHDA) a ensuite été réalisée, utilisant une séquence PRESS standard à un temps d'écho de 136 ms et ciblant le striatum. Sur le même animal, des spectres avant traitement à la 6-OHDA, après traitement et suivant une injection de levodopa ont été acquis. Aucun changement de glutamate n'a pu être mis en évidence, alors qu'une tendance à la réduction de la choline suivant le traitement à la 6-OHDA était observée. Nos résultats indiquent que les changements du métabolisme glutamatergique, ayant lieu dans le cadre de la maladie de Parkinson qui ont été mis en évidence dans le modèle 6-OHDA par d'autres méthodes, ne sont pas reflétés par des changements des concentrations du glutamate total mesuré par RMN in vivo.
|
32 |
Study on Load Response of the Intelligent Electric Vehicle Based on DSPLin, Chien-Hsu 05 July 2011 (has links)
In this paper, the development and control of a switched reluctance motor (SRM) applied to the intelligent electric vehicle are presented. In the SRM control policy, speed control and constant torque/constant power control are implemented with modified PI(RISC) control and a chopped current control(CCC). The control policy can restrain torque ripple effectively, and the vibration and acoustic noise are reduced involuntarily. Simultaneously, The speed response to sudden load change becomes less dramatic. Simulate results suggest that modified PI is more powerful than fuzzy control and PI. In the experiment, this paper compares the advantages and disadvantages of PI, fuzzy control and modified PI under no load, fixed load and unfixed load condition. Finally, a Digital Signal Processor(DSP)is adopted to verify the accuracy of simulation, which contributes to the planning of the program composition flow.
|
33 |
Skaitmeninio reljefo modeliavimo daugiaparametrinis vertinimas, atsižvelgiant į paviršiaus geomorfologines savybes / Multiparameter Evaluation of Digital Terrain Modeling taking into Consideration Surface Geomorphic CharacteristicsKumetaitienė, Aušra 07 July 2005 (has links)
Topicality of the research.
In compiling digital terrain models (DTM) as well as in evaluating them there are widely applied mathematical statistical measuring data processing and analysis methods. However in compiling digital models of relief and evaluating them there are certain peculiarities in mathematical statistical data application. These peculiarities are caused by the fact that relief modeling as well as analysis is considered to belong to the group of geostatic problems. The latter are peculiar for the initial results of measuring which are medium between purely random and purely determined sizes. In solving geo-statistical problems, one has to make use of regionalized data, the stochastic characteristics are the functions of geographic positions of the territory. In modeling the relief the surface geomorphologic peculiarities determine the characteristics of the functions of geographical position. Theoretical grounding of the methods used in modeling the relief surface (e.g., kriging, spline, invert distance weight (IDW), polynomal) is based on the statistical analysis of the random values. Due to the fact that the characteristics of geo-statistical measuring data are preconditioned by the geographic position, not in all territories there are equally suitable certain methods of modeling and parameters of modeling algorithms. The mentioned above reasons determine the fact that there do not exist unified digital terrain modeling methods and types, to be equally well... [to full text]
|
34 |
Skaitmeninio reljefo modeliavimo daugiaparametrinis vertinimas, atsižvelgiant į paviršiaus geomorfologines savybes / Multiparameter Evaluation of Digital Terrain Modeling taking into Consideration Surface Geomorphic CharacteristicsKumetaitienė, Aušra 07 July 2005 (has links)
Topicality of the research.
In compiling digital terrain models (DTM) as well as in evaluating them there are widely applied mathematical statistical measuring data processing and analysis methods. However in compiling digital models of relief and evaluating them there are certain peculiarities in mathematical statistical data application. These peculiarities are caused by the fact that relief modeling as well as analysis is considered to belong to the group of geostatic problems. The latter are peculiar for the initial results of measuring which are medium between purely random and purely determined sizes. In solving geo-statistical problems, one has to make use of regionalized data, the stochastic characteristics are the functions of geographic positions of the territory. In modeling the relief the surface geomorphologic peculiarities determine the characteristics of the functions of geographical position. Theoretical grounding of the methods used in modeling the relief surface (e.g., kriging, spline, invert distance weight (IDW), polynomal) is based on the statistical analysis of the random values. Due to the fact that the characteristics of geo-statistical measuring data are preconditioned by the geographic position, not in all territories there are equally suitable certain methods of modeling and parameters of modeling algorithms. The mentioned above reasons determine the fact that there do not exist unified digital terrain modeling methods and types, to be equally well... [to full text]
|
35 |
Design of tapered and straight stator pole switched reluctance machinesSitsha, Lizo M. M. 04 1900 (has links)
Thesis (MEng)--University of Stellenbosch, 2000. / ENGLISH ABSTRACT: This thesis deals with the design and optimisation of medium power traction switched
reluctance machines with tapered and straight stator poles. Only the prototype of the
tapered stator pole machine is constructed and evaluated in this study.
A non-commercial finite element package is used in the design and optimisation
of the machines. The finite element method is applied directly in the optimisation
procedure to optimise the design of the machines in multi-dimensions. The lumped
circuit analysis method is used only for the purpose of verifying some of the finite
element calculated. It is not used in the optimisation procedure.
The performance characteristics of the tapered and straight stator pole machines
are compared and discussed and the tapered stator pole machine is found to have
better torque performance. Also the calculated and measured static torque versus rotor
position characteristics of the tapered stator pole machine are compared and discussed. / AFRIKAANSE OPSOMMING: Die tesis beskryf die ontwerp en optimering van medium drywing trekkrag geskakelde
reluktansie masjiene met tapse en reguit stator pole. Slegs 'n prototipe van die tapse
stator pool masjien is gebou en geëvalueer.
Die masjiene is ontwerp en geoptimeer met behulp van 'n nie-kommersiële eindige
element metode pakket. Die eindige element metode is direk in die optimerings algoritme
gebruik vir die optimering van die masjiene in multi-dimensies. Die gekonsentreede
parameter stroombaananalise is slegs gebruik om sommige van die eindige
element berekenings te verifeer.
Die vermoës van die tapse en reguit stator pool masjiene is vergelyk en bespreek.
Die resultate toon dat die tapse stator pool masjien se draaimoment vermoë beter is as
die van die reguit stator pool masjien. Die berekende en gemete statiese draaimoment
teenoor rotorposisie van die tapse stator pool masjien is ook vergelyk en bespreek.
|
36 |
Analyse protéomique ciblée à haute résolution : un outil puissant pour le diagnostic clinique à partir de prélèvements de tissus amyloïdes bruts / Targeted proteomics analysis at high resolution : a powerful tool for the clinical diagnosis from raw amyloid biopsy samplesLiuu, Sophie 24 November 2014 (has links)
L'amylose une maladie rare, caractérisée par des agrégats insolubles de protéines extracellulaires. Trente types d'amyloses sont répertoriés et différenciés par la protéine amyloïdogène associée. Leur identification repose sur l'analyse immunohistochimique du tissu malade. Cependant, l'interprétation peut être ambigüe. La micro-dissection laser (LCM) et la spectrométrie de masse sont une alternative prometteuse. Nous avons développé une approche protéomique ciblée à partir de tissus traités par ultrasons. Nous avons montré que les biopsies prélevées chez des patients atteints de différents types d'amyloses peuvent être protéolysées sous ultrasons, ce qui augmente l'efficacité et réduit le temps de la digestion (90s au lieu de 15h), tout en minimisant la quantité de matériel nécessaire. Après une première étape de protéomique sans a priori pour le diagnostic clinique des patients présentant une amylose dans différents organes/tissus (reins, poumons, glandes salivaires, testicule, humeur vitrée et rate), nous avons optimisé une méthode de criblage dédiée à un transfert technologique vers les départements cliniques français. Pour cela, deux méthodes montrent des résultats très encourageants : la SRM (selected reaction monitoring) sur un spectromètre de masse à basse résolution, disponible dans certains laboratoires cliniques et la PRM (parallel reaction monitoring) accessible sur les instruments de dernière génération à très haute résolution, qui fournit rapidement des résultats. En conclusion, nous proposons ici un protocole spécifique pour le diagnostic robuste et la classification rapide des amyloïdoses. / Amyloidosis is rare disease that appears as an insoluble deposition of specific extracellular proteins. Thirty classes of amyloidosis have been reported and their diagnosis relies on the identification of the associated proteins by immunohistochemistry analysis of the affected tissues. However, its interpretation is highly dependent on the pathologist and can be ambiguous. Laser capture micro-dissection (LCM) and mass spectrometry are a promising alternative. We have developed a targeted proteomics approach from raw tissues treated with ultrasound. We showed that the biopsies taken from patients presenting different classes of amyloidosis can be proteolysed by ultrasonic treatment. This technique increases the efficiency and reduces the time of digestion (90s instead of 15h), while minimizing the amount of material needed. After a first unbiased proteomics study for clinical diagnosis of patients with amyloidosis in various organs/tissues (kidney, lung, salivary glands, testicle, vitreous humor and spleen), we have optimized a dedicated screening method for a technological transfer to the French clinical departments. For this, two methods show very promising results: SRM (selected reaction monitoring) on a low-resolution mass spectrometer, available in some clinical laboratories, and PRM (parallel reaction monitoring) available on the latest generation of high-resolution instruments which provide fast results. In conclusion, we propose here a specific protocol for a robust diagnosis and rapid classification of amyloidoses.
|
37 |
Řízení vztahů s dodavateli pomocí řešení SAP SRM / Supplier resource management by using SAP SRMBečvář, Jan January 2011 (has links)
This diploma thesis is concerned with the issue of supplier resource management by using SAP SRM information system. Main goal is the adjudication if it is important to spend company's resources for optimization of shopping proces and if there exists some return of these resources. All at once this thesis is showing principles, SAP SRM's functions including benefits gained by the implementation and the system using. The practical part analyses the shopping process in ABB Group. Author compares a foregoing solution for an indirect spend management with SAP SRM solution. There was a necessary need to adjust company's processes when the new solution, that was implemented. These changes are modeled later on in this thesis and compared with each other. Added advantages achieved upon the foregoing solution are described as well.
|
38 |
Simulace řídicích struktur elektromechanických systémů / Simulation of Electromechanical System Control StructuresPetruška, Ľubomír January 2010 (has links)
Construction of motor models is the main topic of this project. Mathematical characterization of AC machine, permanent magnet synchronous motor, separately-excited DC motor, series-wound DC motor, permanent magnet DC motor, switched reluctance motor is also described. Design of models is based on mathematical description of particular motors. Models are created in Matlab Simulink. Each model is implemented in continuous and also in discrete time variant. Selected models are implemented also on processor from Freescale 56F800E Hybrid Controller family. Each model has individual graphic user interface. Besides motor models, there is description and easy algorithm of Space Vector Modulation. Model of this method is also created. Models are build-up into a library, which can be used for simulations and tests of control structures. Results of models simulations are presented at the end of this project. Simulation of models that are implemented on processor is also made in Matlab Simulink environment and is compared to simulation of models that are implemented directly in Matlab Simulink.
|
39 |
Modélisation numérique d'assemblage soudé par laser de châssis pour sièges de voiture, sous sollicitations dynamiques / Numerical modeling and failure prediction of laser welded joints in a support of car seatArif, Waseem 10 April 2017 (has links)
De nos jours, les politiques environnementales sont devenues plus strictes envers l’industrie automobile pour réduire les émissions de CO2, donc les structures légères utilisant des matériaux de haute résistance sont d’un grand intérêt. Deux modèles différents EF, à savoir "Solid Refine Model" (SRM) et "Shell Coarse Model " (SCM) ont été développés et sont utilisés comme modèles standard par Faurecia Automotive Seating (Caligny). Le SRM est capable de prédire avec précision le comportement de soudage local, mais malheureusement, en raison de son coût de calcul élevé, le SRM n’est pas adapté à une modélisation de si`ge de voiture complète. D’autre part, le SCM est efficace sur le plan numérique, mais il ne peut pas prédire le comportement de la ligne de soudure. L’objectif de la présente thèse est de développer un modèle EF multi-matèriel dans le logiciel commercial Ls-dyna, qui améliorera le SCM pour permettre une prédiction précise du comportement de la ligne de soudure jusqu’à l’échec avec un coût de calcul raisonnable. Le modèle FE quadrilatère standard est développé et enrichie à l’aide d’une méthode récemment développée appelée "Interpolation Covers Method" (ICM) pour capturer les gradients de la solution avec précision sans raffinement de maillage. Un modèle de matériau élasto-plastique est développé dans le logiciel commercial Ls-dyna qui prend en compte deux matériaux différents à savoir BM et HAZ dans un seul élément de coque. Le modèle généralisé d’endommagement dépendant de l’état de contrainte a été implémenté comme UMAT dans le logiciel commercial Ls-dyna pour prédire l’échec de la ligne de soudure dans SCM. Les différents développements ont permis au SCM de prédire avec précision le comportement complexe de la ligne soudée jusqu’à l’échec, à faible coût de calcul compatible avec les besoins industriels. / Nowadays environmental policies have become more strict towards the automotive industry to reduce the CO2 emission, therefore lightweight structures using high strength materials have become of great interest. Two different FE models namely “Solid Refine Model” (SRM) and “Shell Coarse Model” (SCM) have been developed and are being used as standard models by Faurecia Automotive Seating (Caligny). The SRM is capable to predict accurately the local welding behavior but unfortunately, due to its high computational cost, the SRM is not suitable for a full car seat modeling. On the other hand, the SCM is computationally efficient but it cannot predict the weld line behaviour. The aim of the present thesis is to develop a multimaterial FE model within the Ls-dyna commercial software, which will enhance the SCM to allow the accurate prediction of weld line behavior until failure with a reasonable computational cost. The standard quadrilateral shell FE is developed and enriched using a recently developed method called the “Interpolation Covers Method” (ICM) to capture the solution gradients accurately without mesh refinement. An elasto-plastic material model is developed within Ls-dyna commercial software which takes into account two different materials namely BM and HAZ inside a single shell element. The Generalized Incremental Stress State dependent damage Model has been implemented as a UMAT within Ls-dyna commercial software to predict the weld line failure in SCM. The different developments have allowed the SCM to become able to predict the complex behavior of the welded line accurately until failure, at low computational cost compatible with the industrial needs.
|
40 |
Software Licensing in Cloud Computing : A CASE STUDY ABOUT RELATIONSHIPS FROM ACLOUD SERVICE PROVIDER’S PERSPECTIVEKABIR, SANZIDA January 2015 (has links)
One of the most important attribute a cloud service provider (CSP) offers their customers through their cloud services is scalability. Scalability gives customers the ability to vary the amount of capacity when required. A cloud service can be divided in three service layers, Infrastructure-as-a-Service (IaaS), Platform-as- a-Service (PaaS) and Software-as-a-Service (SaaS). Scalability of a certain service depends on software licenses on these layers. When a customer wants to increase the capacity it will be determined by the CSP's licenses bought from its suppliers in advance. If a CSP scales up more than what was agreed on, then there is a risk that the CSP needs to pay a penalty fee to the supplier. If the CSP invests in too many licenses that does not get utilized, then it will be an investment loss. A second challenge with software licensing is when a customer outsources their applications to the CSP’s platform. As each application comes with a set of licenses, there is a certain level of scalability that cannot be exceeded. If a customer wants the CSP scale up more than usual for an application then the customer need to inform the vendors. However, a common misunderstanding is that the customer expects the CSP to notify the vendor. Then there is a risk that the vendor never gets notified and the customer is in danger of paying a penalty fee. This in turn hurts the CSP’s relationship with the customer. The recommendation to the CSP under study is to create a successful customer relationship management (CRM) and a supplier relationship management (SRM). By creating a CRM with the customer will minimize the occurring misunderstandings and highlight the responsibilities when a customer outsources an application to the CSP. By creating a SRM with the supplier will help the CSP to maintain a flexible paying method that they have with a certain supplier. Furthermore, it will set an example to the remaining suppliers to change their inflexible paying method. By achieving a flexible payment method with the suppliers will make it easier for the CSP to find equilibrium between scalability and licenses.
|
Page generated in 0.0416 seconds