Kyoto University (京都大学) / 0048 / 新制・論文博士 / 工学博士 / 乙第1764号 / 論工博第412号 / 新制||工||185(附属図書館) / 2714 / UT51-46-C673 / (主査)教授 坂井 利之, 教授 佐佐木 綱, 教授 近藤 文治 / 学位規則第5条第2項該当

Kyoto University (京都大学) / 0048 / 新制・論文博士 / 工学博士 / 乙第3499号 / 論工博第1034号 / 新制||工||391(附属図書館) / 5370 / UT51-52-N140 / (主査)教授 椹木 義一, 教授 得丸 英勝, 教授 明石 一 / 学位規則第5条第2項該当

Doctor en Ingeniería Eléctrica. Doctor of Philosophy in Electrical and Electronic Engineering / La potencia nominal de los Sistemas de Conversión de Energía Eólica se ha incrementado constantemente alcanzando niveles de potencia cercanos a los 10 MW. Por tanto, convertidores de potencia de media tensión están reemplazando a los convertidores Back-to-Back de baja tensión habitualmente empleados en la etapa de conversión de energía. Convertidores Modulares Multinivel se han posicionado como una solución atractiva para Sistemas de Conversión de Energía Eólica de alta potencia debido a sus buenas prestaciones. Algunas de estas prestaciones son la capacidad de alcanzar altos voltajes, modularidad y confiabilidad. En este contexto, esta tesis discute la aplicación del Convertidor Modular Matricial Multinivel para conectar Sistemas de Conversión de Energía Eólica de alta potencia. Los modelos matemáticos y estrategias de control requeridas para esta aplicación son descritos y discutidos en este documento. Las estrategias de control propuestas habilitan una operación desacoplada del convertidor, proporcionando seguimiento del máximo punto de potencia en el lado del generador eléctrico del sistema eólico, cumplimiento de normas de conexión en el lado de la red eléctrica y regulación de los condensadores flotantes del convertidor. La efectividad de las estrategias de control propuestas es validada a través de simulaciones y experimentos realizados con un prototipo de laboratorio. Las simulaciones se realizan con un Sistemas de Conversión de Energía Eólica de 10 MW operando a 6.6 kV. Dicho sistema se implementa en el software PLECS. Por otro, se ha desarrollado un prototipo de laboratorio de 6kVA durante el desarrollo de este proyecto. El prototipo de laboratorio considera un Convertidor Modular Matricial Multinivel de 27 módulos Puente-H . El sistema es controlado empleando una plataforma de control basada en una Digital Signal Processor conectada a tres tarjetas del tipo Field Programmable Gate Array que proveen de 50 mediciones análogo-digital y 108 señales de disparo. La entrada del convertidor es conectada a una fuente programable marca Ametek que emula el comportamiento de la turbina eólica. A su vez, la salida del convertidor es conectada a otra fuente programable con capacidad de producir fallas en la tensión. Los resultados obtenidos, tanto en el prototipo experimental como en simulación, confirman la operación exitosa del Convertidor Modular Matricial Multinivel en aplicaciones eólicas de alta potencia. En todos los casos, las estrategias de control propuestas aseguran regulación de la tensión en los condensadores flotantes, seguimiento del máximo punto de potencia en el lado del generador eléctrico del sistema eólico y cumplimiento de normas de conexión en el lado de la red eléctrica. / The nominal power of single Wind Energy Conversion Systems has been steadily growing, reaching power ratings close to 10MW. In the power conversion stage, medium-voltage power converters are replacing the conventional low-voltage back-to-back topology. Modular Multilevel Converters have appeared as a promising solution for Multi-MW WECSs due to their characteristics such as modularity, reliability and the capability to reach high nominal voltages. Thereby, this thesis discusses the application of the Modular Multilevel Matrix Converter (\mc) to drive Multi-MW Wind Energy Conversion Systems (WECSs). The modelling and control systems required for this application are extensively analysed and discussed in this document. The proposed control strategies enable decoupled operation of the converter, providing maximum power point tracking capability at the generator-side, grid-code compliance and Low Voltage Ride Through Control at the grid-side and good steady state and dynamic performance for balancing the capacitor voltages of the converter.\\ The effectiveness of the proposed control strategies is validated through simulations and experimental results. Simulation results are obtained with a 10MW, 6.6 kVM3C based WECS model developed in PLECS software. Additionally, a 5 kVA downscale prototype has been designed and constructed during this Ph.D. The downscale prototype is composed of 27 H-Bridges power cells. The system is controlled using a Digital Signal Processor connected to three Field Programmable Gate Array which are equipped with 50 analogue-digital channels and 108 gate drive signals. Two programmable AMETEK power supplies emulate the electrical grid and the generator. The wind turbine dynamics is programmed in the generator-side power supply to emulate a generator operating in variable speed/voltage mode. The output port of the M3C is connected to another power source which can generate programmable grid sag-swell conditions. Simulation and experimental results for variable-speed operation, grid-code compliance, and capacitor voltage regulation have confirmed the successful operation of the \mc{} based WECSs. In all the experiments, the proposed control systems ensure proper capacitor voltage balancing, keeping the flying capacitor voltages bounded and with low ripple. Additionally, the performance of the generator-side and grid-side control system have been validated for Maximum Power Point Tracking and Low-Voltage Ride Through, respectively.

I moderni motori a combustione interna diventano sempre più complessi L'introduzione della normativa antinquinamento EURO VI richiederà una significativa riduzione degli inquinanti allo scarico. La maggiore criticità è rappresentata dalla riduzione degli NOx per i motori Diesel da aggiungersi a quelle già in vigore con le precedenti normative. Tipicamente la messa a punto di una nuova motorizzazione prevede una serie di test specifici al banco prova. Il numero sempre maggiore di parametri di controllo della combustione, sorti come conseguenza della maggior complessità meccanica del motore stesso, causa un aumento esponenziale delle prove da eseguire per caratterizzare l'intero sistema. L'obiettivo di questo progetto di dottorato è quello di realizzare un sistema di analisi della combustione in tempo reale in cui siano implementati diversi algoritmi non ancora presenti nelle centraline moderne. Tutto questo facendo particolare attenzione alla scelta dell'hardware su cui implementare gli algoritmi di analisi. Creando una piattaforma di Rapid Control Prototyping (RCP) che sfrutti la maggior parte dei sensori presenti in vettura di serie; che sia in grado di abbreviare i tempi e i costi della sperimentazione sui motopropulsori, riducendo la necessità di effettuare analisi a posteriori, su dati precedentemente acquisiti, a fronte di una maggior quantità di calcoli effettuati in tempo reale. La soluzione proposta garantisce l'aggiornabilità, la possibilità di mantenere al massimo livello tecnologico la piattaforma di calcolo, allontanandone l'obsolescenza e i costi di sostituzione. Questa proprietà si traduce nella necessità di mantenere la compatibilità tra hardware e software di generazioni differenti, rendendo possibile la sostituzione di quei componenti che limitano le prestazioni senza riprogettare il software. / Modern Internal Combustion Engines are becoming increasingly complex. The introduction of the EURO VI emission control legislation will require a significant reduction of polluting exhaust. The most critical is the reduction of NOx for diesel engines to be added to those already in force with the last legislation. The development of a new engine includes a series of specific tests on the test bench. The growing number of control parameters of the combustion, have a rise as a consequence of the greater mechanical complexity of the engine itself, causes an exponential increase of the tests to be performed to characterize the entire system. The PhD project is to development on board system analysis of combustion in real time where different algorithms, not yet available in modern control units, are implemented. All this with particular attention to the choice of hardware on which to implement the algorithms of analysis. Creating a platform for Rapid Control Prototyping (RCP) that exploits: most of the sensors in series production car, which is able to reduce the time and cost of experimentation on the powertrain. The proposed solution ensures upgradeability, the ability to maintain a maximum level of technology the computing platform, reduced obsolescence and replacement costs. This property results in the need to maintain the compatibility between different generations of hardware and software, making possible the replacement of those components that limit the performance without redesigning the software.

In der Arbeit wird ein Rahmenkonzept für ein ganzheitliches Qualitätsmanagement für Fallbasierte Systeme im Angebotsengineering erarbeitet. Es vereint die Anforderungen des Total Quality Management nach Kunden-, Prozess- und Mitarbeiterorientierung mit bestehenden Ansätzen und Methoden zur Pflege Fallbasierter Systeme. Das Rahmenkonzept beschreibt anhand Fallbasierter Systeme zur Kostenschätzung im Angebotsengineering notwendige Grundlagen und Elemente, welche für eine systematische Qualitätsmessung und -steuerung der Wissensbasis eines solchen Fallbasierten Systems benötigt werden. Die Art und Weise ihrer Darstellung zeigt gleichzeitig eine Vorgehensweise auf, wie beim Aufbau einer Qualitätsmessung und -steuerung für Fallbasierte Systeme vorgegangen werden kann. / In the thesis a framework for an integrated quality management for case-based reasoning systems (CBR systems) in offer engineering has been developed. The framework conjoins the requirements of Total Quality Management for customer orientation, process orientation and employee-orientation with existing approaches and techniques from case base maintenance and case-based reasoner maintenance. Using a case-based cost estimation system in offer engineering as a case study, the framework describes basic principles and elements for a systematic quality measurement and control of the knowledge base of CBR systems. The principles and elements are described in a specific order that can be taken as a procedure for developing quality measurement and control for CBR systems.

In der Arbeit wird ein Rahmenkonzept für ein ganzheitliches Qualitätsmanagement für Fallbasierte Systeme im Angebotsengineering erarbeitet. Es vereint die Anforderungen des Total Quality Management nach Kunden-, Prozess- und Mitarbeiterorientierung mit bestehenden Ansätzen und Methoden zur Pflege Fallbasierter Systeme. Das Rahmenkonzept beschreibt anhand Fallbasierter Systeme zur Kostenschätzung im Angebotsengineering notwendige Grundlagen und Elemente, welche für eine systematische Qualitätsmessung und -steuerung der Wissensbasis eines solchen Fallbasierten Systems benötigt werden. Die Art und Weise ihrer Darstellung zeigt gleichzeitig eine Vorgehensweise auf, wie beim Aufbau einer Qualitätsmessung und -steuerung für Fallbasierte Systeme vorgegangen werden kann. / In the thesis a framework for an integrated quality management for case-based reasoning systems (CBR systems) in offer engineering has been developed. The framework conjoins the requirements of Total Quality Management for customer orientation, process orientation and employee-orientation with existing approaches and techniques from case base maintenance and case-based reasoner maintenance. Using a case-based cost estimation system in offer engineering as a case study, the framework describes basic principles and elements for a systematic quality measurement and control of the knowledge base of CBR systems. The principles and elements are described in a specific order that can be taken as a procedure for developing quality measurement and control for CBR systems.

Extremsökande reglering (ESC) är en modellfri adaptiv reglermetod som kan användas för att lokalisera den optimala arbetspunkten i olinjära processer. Det har nyligen visats att det finns problem med traditionell ESC om det reglerade systemet är dynamiskt. I den här avhandlingen behandlar vi en ny metod för extremsökande reglering som är applicerbar för både statiska och dynamiska system. Metoden är baserad på att reglera processens arbetspunkt tills det lokala fasskiftet hos processen når ⇡/2. Resultatet är baserat på det faktum att fasskiftet hos processer generellt förändras kraftigt kring optimum, och för låga frekvenser motsvarar optimum ett fasskift på ⇡/2radianer. Regulatorstrukturen som används liknar en faslåst slinga (PLL). Ett olinjärt Kalmanfilter används för att estimera fasen och en integrerande regulator används för att justera arbetspunkten tills fasen når det önskade fasskiftet. Resultaten är illustrerade i ett exempel där den nya regulatorstrukturen används för att optimera produktionen i en kemisk reaktor. / Extremum Seeking Control (ESC) is a model-free adaptive control method to locate and track the optimal working point for nonlinear plants. However, as shown recently, traditional ESC methods may not work well for dynamic systems. In this thesis, we consider a novel ESC loop to locate the optimal operating point for both static and dynamic systems. Considering that the phase-lag of the system undergoes a large shift near a steady-state optimum and reaches the value of ⇡/2attheoptimaloperatingpoint, thenovelESC applies the phase-lag of the target system to track the optimum. An ex-tended Kalman filter is used to ensure the accuracy of the phase estimation. The structure of a phase locked loop (PLL) is employed in combination with an integral controller to lock the phase near ⇡/2, such that the target system will operate near the optimal working point. The controller is demonstrated by application to optimization of the substrate conversion in a chemical re-actor.

Els glicolípids i particularment els glicoesfingolípids són compostos d’interès perquè poden interaccionar amb biofactors tot inhibint o interferint en processos fisiològics de les cèl•lules. Per exemple, els glicoesfingolípids que recobreixen les membranes cel•lulars poden interaccionar en processos de reconeixement amb bactèries, virus i toxines com per exemple la toxina del Còlera la qual inicia el procés d’infecció pel reconeixement de glicolípids com el GM1. Tot i que l’ús d’antibiòtics és el tractament més emprat, la resistència als antibiòtics a zones endèmiques fa necessària la recerca en síntesi d’inhibidors basats en derivats de carbohidrats. Donat que la síntesi de compostos glicoconjugats que presenten multivalència ha resultat competitiva en la preparació d’inhibidors contra patògens en aquest treball s’ha estudiat la síntesi de nous mimètics basats en -galactosilceramides; l’acoblament Sukuki-Miyaura en 2-iodoglicals per obtenir nous precursors de carbohidrats i l’anclat de -galactosilceramides en suports com polímers hiperramificats per tal d’avaluar la seva inhibició front la toxina del Còlera. / Los glicolípidos y particularmente los glicoesfingolípidos son compuestos de interés porque pueden interaccionar con biofactores inhibiendo o interfiriendo en procesos fisiológicos de las células. Por ejemplo, los glicoesfingolípidos que recubren las membranas celulares pueden interaccionar en procesos de reconocimiento con bacterias, virus y toxinas como por ejemplo la toxina del Cólera la cual inicia el proceso de infección a través del reconocimiento de glicolípidos como el GM1. Aunque el uso de antibióticos es el tratamiento más empleado, la resistencia a los antibióticos en zonas endémicas hace necesaria la investigación en síntesis de inhibidores basados en derivados de carbohidratos. Dado que la síntesis de compuestos glicoconjugados que presentan multivalencia ha resultado competitiva en la preparación de inhibidores contra patógenos, en este trabajo se ha estudiado la síntesis de nuevos miméticos basados en -galactosilceramidas; el acoplamiento Sukuki-Miyaura en 2-yodoglicales para obtener nuevos precursores de carbohidratos y el anclado de -galactosilceramidas en suportes como polímeros hiperramificados con el fin de avaluar su inhibición frente la toxina del Cólera. / Glycolipids such as glycosphingolipids are interesting compounds because they can interact with biofactors by inhibiting or interfering in physiological processes on cells. For instance, the glycolipids which present on cellular membranes can interact with bacteria, virus and toxins. In deed, Cholera toxin starts its infective process once it has recognized glycolipids such as GM1. Although the use of antibiotics is the commonest treatment against this disease, the antibiotic resistance in endemic areas makes the investigation in the synthesis of inhibitors based on carbohydrate derivatives necessary. Due to the synthesis of multivalent glycoconjugated compounds have been competitive in order to prepare inhibitors against these pathogens, in the present work we have studied: the synthesis of new mimetics based on -galactosylceramides; the Suzuki-Miyaura cross coupling in 2-iodoglycals in order to obtain new carbohydrate precursors and the anchoring of -galactosylceramides in scaffolds such as hyperbranched polymers in order to evaluate their inhibition binding against to Cholera toxin

<p>The standard way for both ground and aerial vehicles to navigate is to use anInertial Navigation System, INS, containing an Inertial Measurement Unit, IMU,measuring the acceleration and angular rate, and a GPS measuring the position.The IMU provides high dynamic measurements of the acceleration and the angularrate, which the INS integrates to velocity, position and attitude, respectively.While being completely impossible to jam, the dead-reckoned estimates will driftaway, i.e., the errors are unbounded. In conjunction with a GPS, providing lowdynamic updates with bounded errors, a highly dynamic system without any driftis attained. The weakness of this system is its integrity, since the GPS is easilyjammed with simple equipment and powered only by a small standard battery.When the GPS is jammed this system falls back into the behavior of the INS withunbounded errors. To counter this integrity problem a camera can be used aseither a back up to the GPS or as its replacement. The camera provides imageswhich are then matched versus a reference, e.g., a map or an aerial photo, to getsimilar estimates as the GPS would provide. The camera can of course also bejammed by blocking the view of the camera with smoke. Bad visibility can alsooccur due to bad weather, but a camera based navigation system will definitelybe more robust than one using GPS.This thesis presents two ways to fuse the measurements from the camera and theIMU, both of them utilizing the Harris corner detector to find point correspondencesbetween the camera image and an aerial photo. The systems are evaluatedby simulated data mimicking both a low and a high accuracy IMU and a camerataking snapshots of the aerial photo. Results show that for the simulated cameraimages the implemented corner detector works fine and that the overall result iscomparable to using a GPS.</p> / <p>Standardsättet för både flygande och markgående fordon att navigera är att användaett tröghetsnavigeringssystem, innehållande en IMU som mäter acceleration ochvinkelhastighet, tillsammans med GPS. IMU:n tillhandahåller högfrekventa mätningarav acceleration och vinkelhastighet som integreras till hastighet, positionoch attityd. Ett sådant system är omöjligt att störa, men lider av att de dödräknadestorheterna hastighet, position och attityd, med tiden, kommer att driva ivägifrån de sanna värdena. Tillsammans med GPS, som ger lågfrekventa mätningarav positionen, erhålls ett system med god dynamik och utan drift. Svagheten i ettvvisådant system är dess integritet, då GPS enkelt kan störas med enkel och billigutrustning. För att lösa integritetsproblemet kan en kamera användas, antingensom stöd eller som ersättare till GPS. Kameran tar bilder som matchas gentemoten referens ex. en karta eller ett ortofoto. Det ger liknande mätningar som de GPSger. Ett kamerabaserat system kan visserligen också störas genom att blockerasynfältet för kameran med exempelvis rök. Dålig sikt kan också uppkomma pågrund av dåligt väder eller dimma, men ett kamerabaserat system kommer definitivtatt vara robustare än ett som använder GPS.Det här examensarbetet presenterar två sätt att fusionera mätningar från etttröghetssystem och en kamera. Gemensamt för båda är att en hörndetektor, Harriscorner detector, används för att hitta korresponderande punkter mellan kamerabildernaoch ett ortofoto. Systemen utvärderas på simulerat data. Resultatenvisar att för simulerade data så fungerar den implementerade hörndetektorn ochatt prestanda i nivå med ett GPS-baserat system uppnås.</p>

Introduction: Addiction to drugs is a chronic disorder characterized by loss of control over substance use despite adverse personal consequences. Addiction can be conceived as the point where drug use is no longer under volitional control and, becomes characterized by compulsive seeking and taking. Drugs of abuse are believed to target two systems thought to be critical for adaptive behaviour, 1) a goal-oriented system relying on prefrontal cortex activity to exert control over behaviour and 2) a motivation system supported by mesocorticolimbic dopamine transmission. These systems are thought to be subverted in addiction. Interestingly, there is a subset of long-term drug users, 'chippers', who, despite considerable exposure to drug, do not manifest the hallmark loss of control or exaggerated drive for drugs that typifies addicted users. To better understand whether prefrontal function, motivation or both distinguish 'chippers' from addicted individuals, we conducted the follwing experiments. Methods: We first examined the effects of lowering dopamine synthesis on motivation to smoke both nicotine-containing and denicotinized cigarettes in three groups of smokers: (i) low-frequency smokers who have smoked for no more than a year, (ii) low-frequency smokers who have stabilized at this level for at least 3 years, and (iii) high-frequency smokers. Next we used a neurocognitive battery testing regional aspects of prefrontal function in low- vs. high-frequency smokers while sated and following an 18 h abstinence period. Finally we examined the effects of lowering dopamine synthesis on regional prefrontal function. Results: 1) All smokers worked for more nicotine-containing cigarettes than de-nicotinized ones. 2) High-frequency smokers worked for more nicotine-containing cigarettes compared to low-frequency smokers. 3) Lowering dopamine synthesis reduced the self-administration of nicotine-containing cigarettes in all three smoker groups and did so without influencing conscious craving or pleasure. 4) Low-frequency smokers were better than high-frequency smokers at inhibiting an on-going motor response indicated by lower stop signal reaction time, consistent with dysfunction in lateral or dorsomedial prefrontal cortex. 5) Overall, lowering dopamine synthesis did not affect executive function. However, post-hoc analyses revealed that the personality trait of novelty seeking, a hypothesized proxy for baseline dopamine function, predicted changes in executive function subsequent to lowered dopamine synthesis. Using this approach, we discovered that lowering dopamine synthesis altered attentional biases to smoking cues as measured by the smoking Stroop in a pattern consistent with an inverted 'U' relationship between dopamine and performance. Conclusion: These data suggest the following. i) Dopamine transmission is involved in the motivation to smoke nicotine-containing cigarettes, and this role persists across stages of tobacco use and addiction. ii) Response inhibition mediated by dorso-medial prefrontal cortex and right inferior frontal gyrus distinguishes low- from high-frequency smokers. This group difference might influence the ability to restrict smoking, and protect low-frequency smokers from addiction. iii) No group-wise differences in prefrontal function were observed following reduction of dopamine synthesis. However, post-hoc analyses revealed that the personality trait of novelty-seeking, used as a proxy for baseline dopamine reactivity, predicted the effect of reduced dopamine synthesis on a task measuring attention to smoking cues according to an inverted 'U' function. Together, these studies add to our understanding of the role of dopamine in maintaining motivation to obtain nicotine-containing cigarettes, the neurobiological differences between low- and high-frequency smokers and the role of individual differences in personality traits in predicting the effects of dopamine manipulation on task performance. / Introduction : La toxicomanie est un trouble complexe, chronique et qui revient, caractérisée par une perte de contrôle sur la consommation de drogues malgré la menace très réelle de se faire du mal. C'est le point où l'utilisation de drogues n'est plus volontaire mais caractérisée par la recherche et prise de drogues compulsives. La transition à la toxicomanie serait le résultat de changements à des circuits neuronaux induits par la drogue. Le système de la dopamine (DA) méso-cortico-limbique est impliqué dans le motivation, le renforcement et la modulation du contrôle exécutif et le cortex préfrontral (CPF) est impliqué dans le contrôle exécutif. Durant la progression à la toxicomanie, des adaptations à ces systèmes 1) érodent la capacité de résister à la prise de drogues, et 2) exagèrent la saillance encourageante de la drogue et des stimuli associés aux drogues. Ce qui est intéressant c'est que l'exposition à la drogue ne mène pas nécessairement à la toxicomanie. Un sous-ensemble de consommateurs de drogues, les « chippers », ne manifestent pas la perte de contrôle typifiant les toxicomanes. Qu'est-ce qui protège ces gens contre la toxicomanie? Ce qui est remarquable c'est que les différences neurobiologiques des circuits neuraux de la motivation et du contrôle qui distinguent les toxicomanes des chippers n'ont pas encore été étudiées de manière systématique. Méthodes : Nous avons mesuré l'effet d'une manipulation de la DA sur la motivation de fumer et le biais de l'attention vers les stimuli associés à l'action de fumer et sur les tâches qui jaugent la fonction exécutive, contrôlée par le CPF, chez (i) les fumeurs à basse fréquence qui fument depuis un maximum de un an (FBF), (ii) les fumeurs à basse fréquence qui se sont stabilisés à ce niveau pour au moins trois ans (FBFS), et (iii) les fumeurs à haute fréquence stables (FHF). Les résultats principaux sont les suivants. Résultats: 1) Baisser la synthèse de la DA a diminué la consommation de cigarettes contenant de la nicotine chez les 3 groupes de fumeurs mais n'a pas eu d'effet sur le goût conscient ou le plaisir de fumer. 2) Tous les fumeurs ont travaillé plus pour des cigarettes contenant de la nicotine que pour celles qui n'en contenaient pas. 3) Les FHF ont aussi plus travaillé pour les cigarettes avec nicotine que les FBF et FBFS. 4) Les FBF/FBFS étaient meilleurs que les FHF à une tâche consistant d'empêcher une réponse motrice en cours, jaugée par le temps de réaction suivant un signal d'arrêt, un modèle de déficience déjà observé chez les patients avec des lésions focales au CPF latéral et dorso-médial. 5) En général, la déplétion aigue de phénylalanine et tyrosine (DAPT) n'a pas eu d'effet sur la fonction exécutive (FE). Par contre, des analyses post-hoc ont démontré que la recherche de la nouveauté (RN), un index que l'on croit représenter la fonction DA de base, prédisait les changements à la FE induite par la DAPT. En utilisant cette approche, nous avons découvert qu'en accordance avec une fonction « U » inversée, la DAPT modifie les biais de l'attention vers les stimuli associés à l'action de fumer, mesurés par le Stroop de la cigarette. Conclusion: En résumé, l'inhibition de réponses contrôlées par un réseau du CPF dorso-médial/gyrus inférieur droit, distingue les chippers de tabac des FHF. Ceci peut être perçu comme étant un facteur clé contribuant à la capacité de restreindre son habitude de fumer, protégeant ainsi les chippers de tabac contre la progression à la dépendance aux drogues. Nous présentons donc de nouvelles données qui ajoutent à notre compréhension des différences neurobiologiques qui séparent les fumeurs à basse et haute fréquence, et du rôle de la DA dans le maintien de la motivation d'obtenir des cigarettes avec nicotine. Ces données pourraient être utiles pour concevoir des interventions mieux ciblées pour les fumeurs.