An important class of physical systems is those that are driven and dissipative. One such system is the Olami-Feder-Christensen (OFC) model which was proposed as a model for earthquake faults. Previous investigations have shown that the OFC model can be described by equilibrium methods under certain circumstances. This observation has explained several aspects of the OFC model and earthquake faults. However, these studies were done at a relatively high level of noise and for systems with a high degree of homogeneity. But real earthquake faults have a very low level of noise and a large degree of inhomogeneity. In this work, a careful study of the noise and its relation to the stress transfer range, dissipation parameter, and system size is performed. In addition, a modified form of the OFC model is studied, where we added asperities. We carefully examined the effect of the asperities on various statistical properties of the model.

A multifunctional strain sensor based on Surface Acoustic Wave (SAW) Orthogonal Frequency Coding (OFC) technology on a Langasite substrate has been investigated. Second order transmission matrix models have been developed and verified. A new parameterizable library of SAW components was created to automate the layout process. Using these new tools, a SAW strain sensor with OFC reflectors was designed, fabricated and tested. The Langasite coefficients of velocity for strain (γS = 1.699) and Temperature (γT = 2.562) were experimentally determined. The strain and temperature characterization of this strain sensor, along with the coefficients of velocity, have been used to demonstrate both the ability to sense strain and the capability for temperature compensation. The temperature-compensated SAW OFC strain sensor has been used to detect anomalous strain conditions that are indicators of fastener failures during structural health monitoring of aircraft panels with and without noise on a NASA fastener failure test stand. The changes in strain that are associated with single fastener failures were measured up to a distance of 80 cm between the sensor and the removed fastener. The SAW OFC strain sensor was demonstrated to act as an impact sensor with and without noise on the fastener failure test stand. The average measured signal to noise ratio (SNR) of 50, is comparable to the 29.1 SNR of an acoustic emission sensor. The simultaneous use of a high pass filter for impact detection, while a low pass filter is used for strain or fastener failure, demonstrates the multifunctional capabilities of the SAW OFC sensor to act as both as a fastener failure detector and as an impact detector.

<p>Finansiella offshorecentra, eller skatteparadis som de också kallas i dagligt tal, utvecklades som ett alternativ till mellankrigstidens hårt reglerade finansiella marknader. Skatteparadisen har ansetts utgöra räddningen för välbärgades rikedomar genom låga/avsaknad av skatter och en stark banksekretess, medan andra betraktar dem som platser där brottslingar och terrorister tillåts tvätta pengar och finansiera sin verksamhet genom förvaringsplats av kapital. Efter terroristattackerna mot USA den elfte september 2001 tillsammans med stora företagsskandaler som Enron och Parmalat har ett omfattande internationellt arbete med att stänga skatteparadis påbörjats med USA som initiativtagande nation.</p><p>För att undersöka hur skatteparadisen fungerar och vilka incitament som kan finnas för att använda skatteparadis har jag ställt frågan: Vilka faktorer kan påverka kapitalflöden till skatteparadis och vilka konsekvenser kan dessa få?</p><p>Vid besvarade av denna fråga har studien syftet att för det första utforma en modell över vilka faktorer som kan tänkas påverka kapitalflöden till skatteparadis. Därefter ämnar studien undersöka modellen för att se hur det ser ut i verkligheten.</p><p>Med hänsyn till kunskapssynen kritisk rationalism har jag använt en multistrategisk metod, bestående av intervjuer och fallstudie tillsammans med kvantitativa skattesatser, för att besvara problemställningen. Studiens problem angreps med ett abduktivt tillvägagångssätt. Den teoretiska modell som jag har konstruerat, Offshore Financial Center Pricing Model (OFCPM), behandlar främst tidigare forskning om skatteparadis och ekonomisk brottslighet. Det empiriska materialet består av tidigare forskningsresultat, intervjuer, fallstudie och olika länders skattesatser.</p><p>Det som framkommit genom studien är att OFCPM:s olika komponenter; (1) skillnaden i nettoavkastning, (2) en individspecifik nyttonivå för att upptäckt och bestraffad, samt (3) en individspecifik nyttonivå för förlust av anseende kan i teorin visa hur olika sorters politik kan påverka användningen av skatteparadis. Modellen visar även starka band till verkligheten och kan tillämpas för att se hur olika faktorer kan inverka på individers nyttjande av skatteparadis.</p>

Now Convenience Store Sector is most popular franchise chain in Taiwan industry. Especially in such high rate of franchise, it¡¦s more difficult to manage and control. But franchisee make a formal contract with franchiser, is it suitable to operate franchisee by only clear formal lease? In management control system(MCS) field, it has not any research to discuss about how to link different type of MCS which exclusive and simultaneous exist. Therefore, this research belongs to an exploratory study which choose President Chain Store Corp. as interviews in order to find chain convenience store¡¦s MCS. This study visit an important role: Operational Field Consultant(OFC) between franchise and franchisee. The interview target is 4 OFC in Kaohsiung Region of President Chain Store Corp. The research find are: the chain convenience store¡¦s MCS which is outcome control and behavior control exclusive and simultaneous. The outcome control comes from franchiser, and the behavior control comes from OFC. This research understands OFC position and role who plan a conflict solver and a moderator. This study also find the interface effect does not come from budget distribution. It should be the OFC role who negotiate between franchiser and franchisee and make them a profit successfully. The conclusion is as follows: 1. President Chain Store Corp have two different types of MCS. The outcome control comes from franchiser, and the behavior control comes from OFC. 2. The interface effect of MCS is actually exist. 3. The interface effect of CVS may link by OFC, especially OFC play an plan a conflict solver and a moderator.

Finansiella offshorecentra, eller skatteparadis som de också kallas i dagligt tal, utvecklades som ett alternativ till mellankrigstidens hårt reglerade finansiella marknader. Skatteparadisen har ansetts utgöra räddningen för välbärgades rikedomar genom låga/avsaknad av skatter och en stark banksekretess, medan andra betraktar dem som platser där brottslingar och terrorister tillåts tvätta pengar och finansiera sin verksamhet genom förvaringsplats av kapital. Efter terroristattackerna mot USA den elfte september 2001 tillsammans med stora företagsskandaler som Enron och Parmalat har ett omfattande internationellt arbete med att stänga skatteparadis påbörjats med USA som initiativtagande nation. För att undersöka hur skatteparadisen fungerar och vilka incitament som kan finnas för att använda skatteparadis har jag ställt frågan: Vilka faktorer kan påverka kapitalflöden till skatteparadis och vilka konsekvenser kan dessa få? Vid besvarade av denna fråga har studien syftet att för det första utforma en modell över vilka faktorer som kan tänkas påverka kapitalflöden till skatteparadis. Därefter ämnar studien undersöka modellen för att se hur det ser ut i verkligheten. Med hänsyn till kunskapssynen kritisk rationalism har jag använt en multistrategisk metod, bestående av intervjuer och fallstudie tillsammans med kvantitativa skattesatser, för att besvara problemställningen. Studiens problem angreps med ett abduktivt tillvägagångssätt. Den teoretiska modell som jag har konstruerat, Offshore Financial Center Pricing Model (OFCPM), behandlar främst tidigare forskning om skatteparadis och ekonomisk brottslighet. Det empiriska materialet består av tidigare forskningsresultat, intervjuer, fallstudie och olika länders skattesatser. Det som framkommit genom studien är att OFCPM:s olika komponenter; (1) skillnaden i nettoavkastning, (2) en individspecifik nyttonivå för att upptäckt och bestraffad, samt (3) en individspecifik nyttonivå för förlust av anseende kan i teorin visa hur olika sorters politik kan påverka användningen av skatteparadis. Modellen visar även starka band till verkligheten och kan tillämpas för att se hur olika faktorer kan inverka på individers nyttjande av skatteparadis.

No description available.

SAW based sensors can offer wireless, passive operation in numerous environments and various device embodiments are employed for retrieval of the sensed data information. Single sensor systems can typically use a single carrier frequency and a simple device embodiment, since tagging is not required. In a multi-sensor environment, it is necessary to both identify the sensor and retrieve the sensed information. This dissertation presents the concept of orthogonal frequency coding (OFC) for applications to SAW sensor technology. OFC offers all advantages inherent to spread spectrum communications including enhanced processing gain and lower interrogation power spectral density (PSD). It is shown that the time ambiguity in the OFC compressed pulse is significantly reduced as compared with a single frequency tag having the same code length and additional coding can be added using a pseudo-noise (PN) sequence. The OFC approach is general and should be applicable to many differing SAW sensors for temperature, pressure, liquid, gases, etc. Device embodiments are shown and a potential transceiver is described. Measured device results are presented and compared with COM model predictions to demonstrate performance. Devices are then used in computer simulations of the proposed transceiver design and the results of an OFC sensor system are discussed.

Ultra-wideband (UWB) communication new technology with ability to share the FCC allocated frequency spectrum, large channel capacity and data rate, simple transceiver architecture and high performance in noisy environments. Such communication advantages have paved the way for emerging wireless technologies such as wireless high definition video streaming, wireless sensor networks and more. This thesis examines orthogonal frequency coded surface acoustic wave (SAW) correlators for use in advanced UWB communication systems. Orthogonal frequency coding (OFC) and pseudo-noise (PN) coding provides a means for UWB spreading of data. The use of OFC spectrally spreads a PN sequence beyond that of CDMA because of the increased bandwidth; allowing for improved correlation gain. The transceiver approach is still very similar to that of the CDMA approach but provides greater code diversity. Use of SAW correlators eliminates many of the costly components that are needed in the IF block in the transmitter and receiver, and reduces much of the signal processing requirements. The OFC SAW correlator device consists of a dispersive OFC transducer and a wideband output transducer. The dispersive filter was designed using seven contiguous chip frequencies within the transducer. Each chip is weighted in the transducer to account for the varying conductance of the chips and to compensate for the output transducer apodization. Experimental correlator results of an OFC SAW correlation filter are presented. The dispersive filter is designed using seven contiguous chip frequencies within the transducer. SAW correlators with fractional bandwidth of approximately 29% were fabricated on lithium niobate (LiNbO3) having a center frequency of 250 MHz and the filter has a processing gain of 49. A coupling of modes (COM) model is used to predict the experimental SAW filter response. Discussion of the filter design, analysis and measurements are presented. Results are shown for operation in a matched filter correlator for use in an UWB communication system and compared to predictions.

Les personnes vieillissantes doivent composer au quotidien avec des douleurs chroniques. Le but de ce travail est de mieux comprendre les mécanismes sous-jacents qui contribueraient aux douleurs chroniques liées au vieillissement et par là, ouvrir un chemin vers de nouvelles perspectives thérapeutiques. Les contrôles inhibiteurs diffus nociceptifs (CIDN) ont un rôle qui n’est pas des moindres dans le contrôle de la douleur. Des études expérimentales examinant l’effet analgésique de la contre stimulation hétérotopique nociceptive (HNCS), un protocole permettant de tester l’efficacité de ces CIDN, suggèrent que le recrutement des CIDN au sein de cette population était plus faible (i.e. moins d’inhibition) comparé à une population plus jeune. En revanche, les études examinant la sensibilisation centrale induite par sommation temporelle (TS) de la douleur rapportent des résultats mitigés. De plus, une composante importante influençant l’expérience de douleur, les ressources cognitives, dont l’inhibition cognitive, se voient aussi décliner avec l’âge. Premièrement, le recrutement des CIDN a été comparé entre des participants sains, jeunes et des plus âgés avec la HNCS, et le recrutement des mécanismes de sensibilisation centrale avec la TS. La stimulation électrique du nerf sural a été choisie pour permettre de quantifier la douleur, tout en prenant une mesure indicative de la nociception spinale qu’est le réflexe nociceptif spinal (RIII). Nos sujets ont aussi participé à une tâche cognitive (le Stroop), testant l’inhibition cognitive. Deuxièmement, l’efficacité des CIDN ainsi que de l’inhibition cognitive a été testée chez les jeunes et les aînés en imagerie par résonance magnétique (IRM), afin de vérifier la relation entre ces deux mesures psychophysiques et l’épaisseur corticale des régions qui y sont impliquées ainsi que l’effet de l’âge sur celles-ci. Les résultats suggèrent un moindre recrutement des CIDN chez les plus âgés lors de l’expérimentation de la HNCS. Également, les sujets âgés présentaient des capacités d’inhibitions cognitives plus faibles que les jeunes. En plus, une corrélation entre l’inhibition cognitive et la modulation du réflexe RIII par la HNCS a été mise en évidence. Pour l’expérience de TS, les résultats étaient comparables pour les deux groupes, suggérant que les mécanismes impliqués dans la régulation de la douleur ne subiraient pas l’effet de l’âge de la même manière. Pour l’étude de l’épaisseur corticale, on y trouve une diminution globale de l’épaisseur corticale liée à l’âge, mais aussi une corrélation de l’analgésie par la HNCS avec l’inhibition cognitive et également, une relation des deux avec l’épaisseur corticale du cortex orbitofrontal (OFC) latéral gauche, suggérant la possibilité d’une existence d’un réseau neuronal au moins partiellement commun du contrôle inhibiteur descendant sensoriel et cognitif. Ce travail montre que l’effet de l’âge sur les mécanismes centraux de la régulation de la douleur est loin d’être uniforme. Également, il montre une corrélation entre la modulation endogène de la douleur et l’inhibition cognitive, ces deux processus seraient associés à une même région cérébrale. Ces résultats pourraient contribuer à identifier d’autres méthodes thérapeutiques, ouvrant ainsi une nouvelle avenue vers d’autres options dans la prise en charge des douleurs chroniques chez les personnes vieillissantes. / Elderly have to deal daily with chronic pain. The diffuse inhibitory descending controls (DNIC) are much involved in the pain control. It was shown that the DNIC recruitment was lower in elderly than in young population, using the analgesic effect of the heterotopic noxious counter stimulation (HNCS), a protocol allowing testing the efficiency of the DNIC. However, the studies assessing the central sensitization by the temporal summation of pain after repetitive stimuli have reported mixed results, the effect of age is still unclear. In addition, there is an age-related decline of an important component, which has an influence on pain perception, the cognitive resources and especially the cognitive inhibition. The goal of this work is to understand the underling mechanisms of the chronic pain related to the normal aging, which can leads to a new therapeutic perspectives. First, the recruitment of the CIDN was compared between healthy young and elderly participants using the HNCS, and the central sensitization was tested using TS. The sural nerve electric shock stimulation was chosen, because it allows us to have two measures, the pain rating and the nociceptive spinal reflex (RIII), an indicative measure of the nociception. Our participants were also invited to participate in a cognitive task (the Stroop), to assess the cognitive inhibition. Second, the efficacy of the CIDN and the cognitive inhibition in elderly and young participants was tested, but this time in a magnetic resonance imaging session. We have wanted to test the association between these two-psychophysics measures, with the cortical thickness of the regions involved into these two processes, and the effect of the normal aging on them. The results have showed a less recruitment of the DNIC in elderly in the HNCS experiment. Also, the elderly have performed less than young in the cognitive inhibition. In addition, a correlation between the cognitive inhibition and the modulation of the RIII-reflex was found. For the TS experiment, no difference was shown between the two groups, suggesting that aging may affect differently the mechanisms involved in endogenous pain modulation. The morphometric study has showed a global diminution of the cortical thickness with aging. Furthermore, there was an association, between the HNCS analgesia and the performance in cognitive inhibition, and between theses two processes and the cortical thickness of the left lateral OFC. These results suggest an eventual existence of at least a partial neuronal common network for the sensorial and cognitive descending inhibitory control. This thesis has showed that the effect of normal aging on the central mechanisms of the pain regulation might be not uniform. Also, on one hand a correlation between the endogenous modulation of pain and cognitive inhibition was reported, and on the other hand that these two processes would be related to the same cortical area. Together, these findings would help to develop new therapeutic methods and offer more options to the management of pain in the elderly.

Les Troubles Obsessionnels et Compulsifs (TOC) sont un trouble mental sévère et fréquemment résistant. La physiopathologie du trouble se caractérise par des anomalies au sein des boucle cortico-striato-thalamo-cortical entrainant une hyper-activité du cortex orbito-frontal, du cortex cingulaire antérieur, du putamen. Au cours des dernières années, des anomalies structurales et fonctionnelles du cervelet ont de plus été mise en évidence dans les TOC venant compléter le modèle existant.Nous avons mise au point un protocole de traitement par tDCS ciblant le cortex orbito-frontal gauche et le cervelet droit pour les TOC résistants. Dans une première étude, nous avons étudié la faisabilité de ce protocole de traitement dans une étude ouverte. Cette étude a mis en évidence une réduction significative des symptômes dans une population de patient à haut niveau de résistance. Dans une deuxième étude, nous avons évaluer l’effet de ce traitement dans un protocole randomisé, contrôlé et parallèle contre placebo. Cette étude n’a pas confirmé l’efficacité de ce protocole de traitement. Dans cette même population, nous avons au cours du protocole mesuré les paramètres d’excitabilité corticale au niveau du cortex moteur par stimulation magnétique transrânienne. Nous avons ainsi mis en évidence que la tDCS provoquait une augmentation significative des processus d’inhibition (Short Interval Cortical Inhibition : SICI ) et une diminution non significative des processus de facilitation (Intra Cortical Facilitation : ICF). L’étude des effets cliniques et électro-physiologiques de cette approche thérapeutique novatrice dans les TOC résistants n’a pas permis de confirmer son intérêt clinique malgré un impact de ce protocole sur les modifications de l’excitabilité corticale inhérentes aux troubles. Ces données ont été mise en relation avec la littérature afin de proposer des perspectives d’évolution dans l’utilisation de la tDCS dans les TOC résistants / Obsessive-compulsive disorder (OCD) is a severe mental illness. OCD symptoms are often resistant to available treatments. Neurobiological models of OCD are based on an imbalance between the direct (excitatory) and indirect (inhibitory) pathway within this cortico-striato-thalamo-cortical loops, which causes hyperactivation in the orbito-frontal cortex, the cingular anterior cortex, the putamen. More recently, the role of cerebellum in the OCD physiopathology has been brought to light by studies showing structural and functional abnormalities. We proposed to use tDCS as a therapeutic tool for resistant OCD by targeting the hyperactive left orbito-frontal cortex with cathodal tDCS (assumed to decrease cortical excitability) coupled with anodal cerebellar tDCS. In a first study, we studied the feasibility of this treatment protocol in an open-trial. This study found a significant reduction in symptoms in a population with a high level of resistance. In a second study, we evaluated the effect of this treatment in a randomized-controlled trial. This study did not confirm the effectiveness of this intervention. We have assessed motor cortex cortical excitability parameters by transcranial magnetic stimulation. We thus demonstrated that the tDCS caused a significant increase of inhibition processes (Short Interval Cortical Inhibition: SICI) and a nonsignificant decrease in the facilitation processes (Intra Cortical Facilitation (ICF)). In addition, clinical improvement assessed by Clinical Global Impression at the end of the follow-up period (3 months) was positively correlated with SICI at baseline.tDCS with the cathode placed over the left OFC combined with the anode placed over the right cerebellum decreased hyper-excitability in the motor cortex but was not significantly effective in SSRI- resistant OCD patients. These works were discussed in light of the available literature to create future prospect in the field of tDCS treatment for OCD resistant patients