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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Open Innovation by Opening Embedded Systems

Söldner, Constantin, Danzinger, Frank, Roth, Angela, Möslein, Kathrin 14 December 2012 (has links) (PDF)
1 INTRODUCTION With the increasing capabilities of today’s smart phones, the demand of consumers for new applications has risen dramatically. By opening up these smart phones and providing third parties the opportunity to develop “apps” for their systems, producers like Apple and platform owners like Google can offer much more value to their customers. As smart phones are one kind of embedded systems (ES), the question arises if similar development can also take place in other kinds of embedded systems. ES, consisting of hardware and software, are embedded in a device to realize a specific function, in contrast to personal computers, which serve multiple purposes [4,30]. The notion of incorporating external actors in the innovation process has been coined open innovation which has become increasingly popular in research and practice since Chesbrough introduced the term in 2003 [12]. By opening up their innovation processes for external actors, firms could benefit from internal as well as from external ideas. In this paper, the notion of open innovation will be explored in the context of ES. The case of ES is particularly interesting, as it requires not only the opening of innovation processes, but also the opening of the embedded system itself. Some of these platforms are opened only to a small degree like Apple’s iPhone, in order to enable others to create new applications for it. Similar developments also take place for example in the automotive software domain, especially concerning infotainment systems. However, most kinds of ES have been spared out by this development until now. As more than 98% of all chips manufactured are used for ES [10] and high-performing computer chips are getting cheaper [38], opening considerations could also prove valuable for a large number of other application domains. However, opening up innovation processes in the context of ES is challenging from both an organizational and technical perspective. First of all, embedded systems are subject to a variety of constraints in contrast to multi-purpose computing devices, like realtime and security constraints or costs and resource constraints. Second, ES are quite diverse both in their composition and in terms on their requirements. In this paper, we want to explore, how the different properties of embedded systems influence possible open innovation processes. This will be done by drawing on to the characteristics of firms implementing the three core open innovation processes suggested by Gassmann and Enkel (2004) [15] and conceptually explaining how the characteristics of ES enable or hinder open innovation processes. As a result, a classification of the OI processes in terms of ES characteristics is provided.
242

Modularity, antimodularity and explanation in complex systems / Modularité, antimodularité, et explication dans les systèmes complexes / Modularità, antimodularità e spiegazione nei sistemi complessi

Rivelli, Luca 30 November 2015 (has links)
Ce travail concerne principalement la notion de modularité hiérarchique et son utilisation pour expliquer la structure et le comportement dynamique des systèmes complexes au moyen de modèles modulaires hiérarchiques, ainsi qu'un concept de ma proposition, l’antimodularité, relié à la possibilité de la détection algorithmique de la modularité hiérarchique. Plus précisément, je mets en évidence la portée pragmatique de la modularité hiérarchique sur la possibilité de l’explication scientifique des systèmes complexes, c’est-à-dire, systèmes qui, selon une description de base choisie par l’observateur, peuvent être considérés comme composés de parties élémentaires discrètes interdépendantes. Je souligne que la modularité hiérarchique est essentielle même au cours de l’expérimentation visée à découvrir la structure de ces systèmes. Mais la détection algorithmique de la modularité hiérarchique se révèle être une tâche affectée par la démontrée intraitabilité computationnelle de la recherche de la meilleure description modulaire hiérarchique, et par l’excessive cherté computationnelle même des méthodes de détection approximatives de la modularité. L’antimodularité consiste en le manque d’une description modulaire appropriée aux exigences de l’observateur, manque dû ou à l’absence de modularité dans la description basique choisie du système, ou à l’impossibilité de produire algorithmiquement une description hiérarchique valide, en raison des dimensions excessives du système à évaluer en relation à la cherté computationnelle des méthodes algorithmiques. Je souligne, de plus, que la modularité et l’antimodularité dépendent du choix pragmatique d’une spécifique description de base du système, choix fait par l’observateur sur la base de ses objectifs explicatifs. Je montre comment l’antimodularité entrave la possibilité d’appliquer au moins trois types bien connus d’explication: mécanique, déductive-nomologique et computationnelle. Un quatrième type, l’explication topologique, reste par contre indemne. Ensuite j’évalue la présence de modularité dans les systèmes biologiques, avec ses possibles conséquences, et l’éventualité d’encourir dans l’antimodularité en biologie et en autres sciences: éventualité assez probable, au moins dans la biologie des systèmes. Je me permet enfin quelques spéculations métaphysiques et historiques plutôt libres. D’un point de vue métaphysique, l’antimodularité semble suggérer une position possible, selon laquelle les espèces naturelles sont modules qui ont été détectés et, en raison de l’intraitabilité computationnelle de la détection de la meilleure description modulaire hiérarchique, il est improbable qu’ils constituent la meilleure façon possible de décrire le monde, parce que la modularité des espèces naturelles assez probablement ne reflète pas la meilleure modularité possible du monde. D’un point de vue historique, l’utilisation croissante des méthodes computationnels pour la détection de la modularité ou pour la simulation de systèmes complexes, en particulier dans certains domaines de la recherche scientifique, suggère la possibilité d’imaginer une multiplicité de disciplines scientifiques émergentes, guidées par une production croissante et auto-alimentante d’explications potentiellement inintelligibles pour les capacités cognitives humaines. Cela, à mon avis, constituerait un changement historique dans la science, qui, s’il n’a pas déjà eu lieu, pourrait bien être sur le point de se produire. / This work is mainly concerned with the notion of hierarchical modularity and its use in explaining structure and dynamical behavior of complex systems by means of hierarchical modular models, as well as with a concept of my proposal, antimodularity, tied to the possibility of the algorithmic detection of hierarchical modularity. Specifically, I highlight the pragmatic bearing of hierarchical modularity on the possibility of scientific explanation of complex systems, that is, systems which, according to a chosen basic description, can be considered as composed of elementary, discrete, interrelated parts. I stress that hierarchical modularity is also required by the experimentation aimed to discover the structure of such systems. Algorithmic detection of hierarchical modularity turns out to be a task plagued by the demonstrated computational intractability of the search for the best hierarchical modular description, and by the high computational expensiveness of even approximated detection methods. Antimodularity consists in the lack of a modular description fitting the needs of the observer, a lack due either to absence of modularity in the system’s chosen basic description, or to the impossibility, due to the excessive size of the system under assessment in relation to the computational cost of algorithmic methods, to algorithmically produce a valid hierarchical description. I stress that modularity and antimodularity depend on the pragmatic choice of a given basic description of the system, a choice made by the observer based on explanatory goals. I show how antimodularity hinders the possibility of applying at least three well-known types of explanation: mechanistic, deductive-nomological and computational. A fourth type, topological explanation, remains unaffected. I then assess the presence of modularity in biological systems, and evaluate the possible consequences, and the likelihood, of incurring in antimodularity in biology and other sciences, concluding that this eventuality is quite likely, at least in systems biology. I finally indulge in some metaphysical and historical speculations: metaphysically, antimodularity seems to suggest a possible position according to which natural kinds are detected modules, and as such, due to the computational hardness of the detection of the best hierarchical modular description, they are unlikely to be the best possible way to describe the world, because the modularity of natural kinds quite probably does not reflect the best possible modularity of the world. From an historical point of view, the growing use of computational methods for modularity detection or simulation of complex systems, especially in certain areas of scientific research, hints at the envisioning of a multiplicity of emerging scientific disciplines guided by a self- sustained, growing production of possibly human-unintelligible explanations. This, I suggest, would constitute an historical change in science, which, if has not already occurred, could well be on the verge of happening. / Questo lavoro riguarda principalmente il concetto di modularità gerarchica e il suo impiego nello spiegare la struttura e il comportamento dinamico di sistemi complessi mediante modelli modulari gerarchici, nonché un concetto di mia proposta, l’antimodularità, legato alla possibilità del rilevamento algoritmico di modularità gerarchica. Nello specifico, evidenzio la portata pragmatica della modularità gerarchica sulla possibilità di spiegazione scientifica dei sistemi complessi, cioè sistemi che, secondo una descrizione di base scelta dall’osservatore, possono essere considerati come composti da parti elementari discrete interrelate. Sottolineo che la modularità gerarchica è essenziale anche nel corso della sperimentazione volta a scoprire la struttura di tali sistemi. Il rilevamento algoritmico della modularità gerarchica si rivela essere un compito affetto dalla dimostrata intrattabilità computazionale della ricerca della migliore descrizione modulare gerarchica, e affetto dal comunque elevato costo computazionale anche dei metodi di rilevamento approssimati della modularità. L’antimodularità consiste nella mancanza di una descrizione modulare adatta alle esigenze dell’osservatore, mancanza dovuta o all’assenza di modularità nella descrizione di base del sistema scelta dall’osservatore, o all’impossibilità di produrre algoritmicamente una sua descrizione gerarchica valida, per le dimensioni eccessive del sistema da valutare in rapporto al costo computazionale dei metodi algoritmici. Sottolineo che modularità e antimodularità dipendono dalla scelta pragmatica di una certa descrizione di base del sistema, scelta fatta dall’osservatore sulla base di obiettivi esplicativi. Mostro poi come l’antimodularità ostacoli la possibilità di applicare almeno tre tipi noti di spiegazione: meccanicistica, deduttivo- nomologica e computazionale. Un quarto tipo di spiegazione, la spiegazione topologica, rimane sostanzialmente immune dalle conseguenze dell’antimodularità. Valuto quindi la presenza di modularità nei sistemi biologici, e le sue possibili conseguenze, nonché l’eventualità di incorrere nell’antimodularità in biologia e in altre scienze, concludendo che questa eventualità è abbastanza probabile, almeno in biologia dei sistemi. Infine, mi permetto alcune speculazioni metafisiche e storiche piuttosto libere. Dal punto di vista metafisico, l’antimodularità sembra suggerire una posizione possibile secondo cui i generi naturali sono moduli che sono stati rilevati, e in quanto tali, a causa dell’intrattabilità computazionale del rilevamento della migliore descrizione modulare gerarchica, è improbabile che essi siano il miglior modo possibile per descrivere il mondo, perché la modularità dei generi naturali molto probabilmente non rispecchia la migliore modularità possibile del mondo. Da un punto di vista storico, il crescente utilizzo di metodi computazionali per il rilevamento della modularità o per la simulazione di sistemi complessi, in particolare in alcuni settori della ricerca scientifica, suggerisce la possibilità di immaginare una molteplicità di discipline scientifiche emergenti, guidate dalla produzione di spiegazioni potenzialmente inintelligibili dal punto di vista cognitivo umano, produzione che potrebbe iniziare ad autoalimentarsi, portando potenzialmente ad una crescita inarrestabile. Suggerisco che questo scenario cos- tituirebbe un cambiamento epocale nel campo della scienza, che, se non è già avvenuto, potrebbe benissimo essere sul punto di realizzarsi.
243

Redécouvrir la conscience par le rêve : le débat entre théories cognitives et théories non cognitives de la conscience à l’épreuve de la recherche sur le rêve / [rediscovering consciousness by the dream : the debate between cognitive and non-cognitive theories of consciousness to the test of scientific research on dreaming]

Crespin, Ludwig 25 November 2016 (has links)
En 1995, le philosophe Ned Block a proposé de distinguer deux notions de conscience : une notion purement expérientielle, la « conscience phénoménale », qui désigne l’effet que cela fait d’être dans tel ou tel état mental, et une notion purement fonctionnelle, la « conscience d’accès », ou « accès cognitif » (Block, 2007), entendue comme la capacité du sujet à utiliser ses représentations pour le contrôle de ses opérations cognitives, et, via ces opérations, pour le contrôle de la parole et de l’action. Block défend depuis l’hypothèse très discutée selon laquelle l’expérience consciente, ou « conscience phénoménale », déborde l’accès cognitif du sujet. L’objet central de ce travail est de mettre cette hypothèse à l’épreuve de la recherche sur le rêve. Nous y soutenons principalement les trois arguments suivants : 1. Sous hypothèse d’une continuité entre les propriétés de la mémoire onirique et vigile, on peut objectiver la réalité d’expériences conscientes pendant le sommeil en s’appuyant sur le critère canonique de rapportabilité. De fait, de nombreuses études convergent pour montrer que les sujets peuvent rapporter un contenu onirique qui reflète de manière non équivoque un stimulus présenté plus d’une minute avant l’éveil – ce qui, au regard de l’extrême évanescence de la perception subliminale, ne pourrait pas être le cas si le rêve était un processus inconscient. Sachant que le sommeil s’accompagne d’une sévère désactivation des aires frontales, et en particulier du cortex dorsolatéral préfontal (DlPFC), un tel résultat tend à questionner le modèle neuropsychologique de « l’espace neuronal global de travail » (Dehaeneet Naccache, 2001 ; Dehaene et al, 2006) qui fait dépendre la perception consciente de l’activation de ces aires.2. Le fait même d’objectiver la réalité d’expériences conscientes pendant le sommeil à travers des récits de rêves recueillis à l’éveil implique cependant de reconnaître que ces mêmes expériences ont été remarquées par le dormeur et qu’elles relèvent en ce sens minimum de la conscience d’accès. Pour autant, certains désordres cognitifs de la conscience rêvante, tels notamment que la cécité au changement, suggèrent qu’il ne suffit pas qu’une expérience soit remarquée par le dormeur pour qu’elle relève de plein droit de la conscience d’accès : il fautencore qu’elle puisse être maintenue activement dans la mémoire de travail. Le phénomène bien connu des « dissociations identité-apparence » (Schwartz, 1999) suggère pareillement que la rapportabilité d’une expérience onirique n’assure pas qu’elle soit posée pour le contrôle des opérations cognitives dans le rêve.3. Dès l’instant où l’on a pu objectiver la réalité des expériences oniriques à travers le critère canonique de rapportabilité, il devient possible – là encore, sous hypothèse de continuité –d’inférer de façon empiriquement contraignante l’existence d’une vie consciente non rapportable du dormeur. Se pose alors la question de savoir si un tel vécu, dont on peut soutenir qu’il constitue une forme d’inconscient psychique, relève de plein droit de la conscience d’accès.Enfin, à travers ces trois arguments portant spécifiquement sur la conscience onirique, nous montrons que la recherche sur le rêve permet de questionner de façon privilégiée la notion d’une nécessaire rapportabilité de l’expérience consciente et de faire valoir le concept de modularité de la conscience qui sous-tend l’hypothèse blockéenne du débordement expérientiel (Block, 1995, 1997). / In 1995, the American philosopher Ned Block proposed to distinguish between two notions of consciousness: “Access-consciousness” and “Phenomenal-consciousness”. “P-consciousness” is experience: it refers to what it is like to be in a certain mental state. “Aconsciousness” is a purely functional notion. A mental state is A-conscious when it allows the subject to cognitively control its reasoning, speech and action. Since 1995, Block supports the controversial hypothesis according to which conscious experience overflows our cognitive access to it. The main goal of this work is to assess this hypothesis from the point of view of scientific research on dreaming. This PhD dissertation makes the three following points : 1. Assuming there is a continuity between waking and dreaming memory, one can objectively verify that dreams are conscious experiences that occur during sleep relying on the canonical criterion of reportability. Indeed, many studies show that subjects can report on a dream content that unequivocally reflects a stimulus that has occurred more than one minute before awakening – which couldn’t be had this dream content been unconsciously processed. Considering that sleeping involves a severe deactivation of the frontal areas of the brain, especially of the dorsolateral prefrontal cortex (DlPFC), this result seems to call into question the global neuronal workspace theory of consciousness. Indeed, according to this theory the activation of these very areas is a necessary condition for a conscious perception to occur(Dehaene & Naccache, 2001; Dehaene et al, 2006). 2. There is no way though to demonstrate scientifically that dreams are conscious experiences of the sleeper without implying they were noticed during sleep, which, in turn, implies an elementary level of access. Still, certain cognitive disorders of our dreaming consciousness, such as change blindness, suggest that, due to a severe weakness of working memory, noticing an experience during sleep might not suffice to constitute a genuine cognitive access to it. The well-known phenomenon called “identity-appearance dissociation” (Schwartz, 1999) also suggests that dreaming experiences that are reportable on awakening might not always be poised for cognitive control in the dream. 3. Once the reality of conscious experiences during sleep is objectively established relying on the criterion of reportability, it becomes possible – again under the assumption of continuity - to empirically infer the existence of dreaming experiences that the subject cannot report. The following question then arises: are these experiences, which can be seen as a form of unconscious mental life, access-conscious? Finally, and more generally, we show that the results of dreaming research offer a vantage point both to call into question the notion that conscious experience is necessarily reportable and to support the concept of modularity of our conscious selves (Nagel, 1971; Gazzaniga,1985) that underlies Block’s overflow hypothesis (Block, 1995, 1997)
244

PRODUCT SERVICE SYSTEMS AND MODULAR DEVELOPMENT : Implications and Opportunities in the Construction Equipment Industry / Produkt och Servicesystem med Modulär utveckling : Konsekvenser och Möjligheter i Entreprenad-branschen

Gustafsson, Rikard, Blomqvist, Andreas January 2013 (has links)
Volvo Construction Equipment is considering applying modular design to their organisation in order to constrain the growing intangible information and parts assortment within the company, and as well to enable a rearrangement of production, sales and logistics in the near future of organisational growth and industrial footprint. Hence the purpose of this thesis is to investigate the opportunities and threats of implementing modular design to Volvo Construction Equipment. The analysis is scoped on the generic aspects of modularity and the organisational weaknesses within Volvo CE towards implementing a new organisational structure, product design and production with modular design. Modularity enables the company to move towards decupling the constraints of tangible sales and provides an opportunity to offer Product Service Systems as a Total Solution for each individual customer. By implementing the authors common knowledge and education within engineering revolving tangible and intangible products and services alongside with innovation, together with informal interviews of stakeholders, the results of the thesis was reached. The analysis of the results was reached by implementing Design Research Methodology to the structure of the thesis, research method and interviews made. There is a distinct opportunity for Volvo CE to implement modular design since the informational flows, innovation, research and development is enhanced by a correct modular design. Although there is a distinct risk in changing a well-established product design, development process and organisational structure, the opportunities to create a product service system strategy and to re harvest and recycle value within the company with modularity outweigh the risk. Incomprehension of how to optimize a modular design may amplify the reasons why Volvo CE is considering revising their products and organisation with modularity, thus the authors recommend implementing a generic and specific education in modularity within Volvo CE to ensure a shared language of modularity and enhance traceability of the development within the company. In order to enhance the organisational velocity around development, the authors also recommend a new computer environment which enables the different disciplines of engineering and marketing to modularise the product, services and processes while keeping the comprehension of the subject close to hand. This enables the organisational structure to change and improve towards modular deployment and to further accelerate Volvo CE’s growth, market share and revenue. / Volvo Construction Equipment överväger att tillämpa en modulär design till sin organisation i syfte att begränsa den växande immateriella information och det växande sortiment av delar inom företaget som finns idag. Volvo ser även till möjligheterna med modulär design för att möjliggöra en omflyttning av produktion, försäljning och logistik inom den närmaste framtiden för organisatorisk tillväxt och för att minska det industriella fotavtrycket. Därav syftet med denna uppsats; att undersöka möjligheter och hot för att genomföra modulär design i Volvo Construction Equipment. Analysen är fokuserad på generiska aspekter på modularitet och organisatoriska svagheter inom Volvo CE mot att genomföra en ny organisationsstruktur, produktdesign och produktion med modulär design. Modularitet möjliggör för företaget att gå mot att minska begränsningen av materiell försäljning och ger en möjlighet att erbjuda system med Product och Service lösningar som en helhetslösning för varje enskild kund. Genom att implementera författarnas gemensamma kunskap och utbildning inom teknik roterande kring materiella och immateriella produkter samt tjänster tillsammans med innovation, och med informella intervjuer av intressenter, har resultaten i denna avhandling uppnåtts. Analysen av resultaten uppnåddes genom att implementera metodiken Design Research Methodology till strukturen, forskningsmetod och gjorda intervjuer i avhandlingen. Det finns en tydlig möjlighet för Volvo CE att genomföra modulär design eftersom de informativa flöden, innovation, forskning och utveckling förstärks av en korrekt modulär design. Även om det finns en klar risk i att ändra en väletablerad produkts design, utveckling process och organisations struktur, är möjligheterna i att skapa en produkt strategi med servicesystem och att återvinna återvinna värde i företaget med modularitet väl värt risken. Oförståelse för hur man optimerar en modulär design kan innebära ytterligare risker och förklarar varför Volvo CE överväger revidera sina produkter och organisation med en ny design, och då kanske en modulär struktur. Detta har lett till att författarna rekommenderar att genomföra en allmän och specifik utbildning i modularitet inom Volvo CE för att säkerställa ett gemensamt språk för modularitet och öka spårbarheten av utvecklingen inom företaget. För att öka den organisatoriska hastigheten kring utveckling, rekommenderar författarna också en ny datormiljö som gör att de olika disciplinerna i teknik och marknadsföring ligger närmre till hands för att modularisera produkter, tjänster och processer samtidigt som förståelsen av ämnet blir enklare att uppnå. Detta maximerar effektiviteten i den organisatoriska strukturen för att förändra och förbättra mot en modulär utbyggnad och att ytterligare påskynda Volvo CE : s tillväxt , marknadsandelar och intäkter
245

Emergence de structures modulaires dans les régulations des systèmes biologiques : théorie et applications à Bacillus subtilis

Goelzer, Anne 04 November 2010 (has links)
Cette thèse consiste à étudier l'organisation du système de contrôle des voies métaboliques des bactéries afin de dégager des propriétés systémiques révélant son fonctionnement. Dans un premier temps, nous montrons que le contrôle des voies métaboliques est hautement structuré et peut se décomposer en modules fortement découplés en régime stationnaire. Ces modules possèdent des propriétés mathématiques remarquables ayant des conséquences importantes en biologie. Cette décomposition, basée intrinsèquement sur la vision système de l'Automatique, offre un cadre théorique formel général d'analyse du contrôle des voies métaboliques qui s'est révélé effectif pour analyser des données expérimentales. dans un deuxième temps, nous nous intéressons aux raisons possibles de l'émergence de cette structure de contrôle similaire. Nous identifions un ensemble de contraintes structurelles agissant au niveau de la répartition d'une ressource commune, les protéines, entre les processus cellulaires. Respecter ces contraintes pour un taux de croissance donné conduit à formaliser et résoudre un problème d'optimisation convexe non différentiable, que nous appelons Resource balance Analysis. Ce problème d'optimisation se résout numériquement à l'échelle de la bactérie grâce à un problème de Programmation Linéaire équivalent. plusieurs propriétés sont déduites de l'analyse théorique du critère obtenu. Tout d'abord, le taux de croissance est structurellement limité par la répartition d'une quantité finie de protéines entre les voies métaboliques et les ribosomes. Ensuite, l'émergence des modules dans les voies métaboliques provient d'une politique générale d'économie en protéines chez la bactérie pour gagner du taux de croissance. Certaines stratégies de transport bien connues comme la répression catabolique ou la substitution de transporteurs haute/basse affinités sont prédites par notre méthode et peuvent alors être interprétées comme le moyen de maximiser la croissance tout en minimisant l'investissement en protéines. / This thesis consist in studying the organization of the control system of metabolic pathways of bacteria to identify systemic properties revealing its operation. At first, we show that control of metabolic pathways is highly structured and can be decomposed into modules strongly decoupled in steady-state. These modules are defined by their singular mathematical properties having important implications in biology. This decomposition, based inherently on the system outlook of automatic control, offers a formal theoretical analysis of general control of metabolic pathways, which has been effective in analysing experimental data. In a second step, we consider the possible reasons for the emergence of this modular control structure. We identify a set of structural constraints acting at the distribution of a common resourc, the proteins between cellular processes. Satisfying these constraints for a given growth rate leads to formalize and to solve a non-differentiable convex optimization problem, that we call Resource Balance Analysis. This optimization problem is solved numerically at the scale of the bacteria through an equivalent linear programming problem. Several properties are derived from theoretical analysis of the obtained criterion. Firts, the growth rate is structurally limited by the distribution of a finite amount of proteines between the metabolic pathways and the ribosomes. Second, the emergence of modules in metabolic pathways arises from a policy of economy in proteins in the bacterium to increase the growth rate. Some well known transport strategies such as catabolite repression of the substitution between low/highaffinity transporters are predicted by our methods and could consequently be interpretd as ways to maximize growth while minimizing investment in proteins.
246

Dimensionality, noise separation and full frequency band perspectives of ICA in resting state fMRI:investigations into ICA in resting state fMRI

Starck, T. (Tuomo) 19 August 2014 (has links)
Abstract The concept of resting state functional magnetic resonance imaging (fMRI) is built onto an original finding in 1995 that brain hemispheres present synchronous signal fluctuations with distinct patterns. fMRI measurements rely on blood oxygenation changes that indirectly mirror neural activity. Therefore, the origin of functional connectivity patterns, resting state networks (RSNs), has been a widely debated research question and numerous contributing factors have been identified. According to current understanding the fluctuations reflect maintenance of the system integrity in addition to spontaneous thought and action processes in the resting state. A popular method to study the functional connectivity in resting state fMRI is spatial independent component analysis (ICA) that decomposes signal sources into statistically independent components. The dichotomy of functional specialization versus functional integration has a correspondence in fMRI studies where RSNs play the integrative viewpoint of brain function. Although canonical large-scale RSNs are broadly distributed they also express modularity that can be accomplished by ICA with a high number of estimated components. The characteristics of high ICA dimensionality are broadly investigated in the thesis. An enduring issue in resting state research has been the confounding noise sources like motion and cardiorespiratory processes which may hamper the analysis. In this thesis the ability of ICA to separate these noise sources from the default mode network, a major RSN, is studied. Additionally, the suitability of ICA for full frequency spectrum analysis, a relatively rare setting in biosignal analysis, is investigated. The results of the thesis support the viewpoint of ICA as a robust analysis method for functional connectivity analysis. Cardiorespiratory and motion induced noise did not confound the functional connectivity analyses with ICA. High dimensional ICA provided better signal source separation, revealed the modular structure of the RSNs and pinpointed the specific aberrations in the autism spectrum disorder population. ICA was also found applicable for fully explorative analysis in both the spatial and temporal domains and indicated functional connectivity changes induced by transcranial bright light stimulation. / Tiivistelmä Konsepti lepotilan tutkimisesta toiminnallisella magneettikuvauksella (engl. functional magnetic resonance imaging, fMRI) on rakentunut vuonna 1995 tehdylle löydökselle aivopuoliskojen välillä synkronisesta signaalivaihtelusta. Mittaukset perustuvat veren hapetuksen muutoksiin, jotka epäsuorasti heijastelevat hermostollista toimintaa. Tämän takia toiminnallisen kytkennällisyyden muodot, lepotilaverkostot, ovat olleet laajasti väitelty tutkimusaihe ja monia verkostoihin vaikuttavia tekijöitä onkin tunnistettu. Nykykäsityksen mukaan signaalivaihtelut lepotilassa heijastelevat järjestelmän yhtenäisyyden ylläpitoa spontaanin ajattelun ja toiminnan lisäksi. Suosittu menetelmä toiminnallisen kytkennällisyyden tutkimiseen lepotilan fMRI:ssä on spatiaalinen itsenäisten komponenttien analyysi (engl. independent component analysis, ICA), joka hajottaa signaalilähteet tilastollisesti itsenäisiin komponentteihin. Aivotoiminnan mallintamisessa kahtiajaolla toiminnalliseen erikoistumiseen ja toiminnalliseen integraatioon on vastaavuus fMRI-tutkimukseen, jossa lepotilaverkostot vastaavat toiminnallisen integraation näkökulmasta. Vaikka kanoniset lepotilaverkostot ovat laaja-alaisia, ne ovat toisaalta modulaarisia, jota voidaan tutkia tutkimalla korkean komponenttimäärän ICA-hajotelmaa. Korkea- dimensioisen ICA-hajotelman ominaisuuksia tutkitaan laajasti tässä väitöskirjassa. Kestoaihe lepotilatutkimuksessa on ollut analyysiä hankaloittavien kohinalähteiden kuten liikkeen ja kardiorespiratoristen prosessien vaikutus. Väitöskirjassa tutkitaan ICA:n kykyä erotella kohinalähteitä ’default mode’ -verkostosta, joka on merkittävin lepotilaverkosto. Lisäksi tutkitaan ICA:n soveltuvuutta täyden taajuuskaistan analysointiin, joka on verrattain harvinaista biosignaalien analyysissä. Väitöskirjan tulokset tukevat näkemystä ICA:n suorituskyvystä toiminnallisen kytkennällisyyden analyysissä. Kardiorespiratorinen ja liikkeestä lähtöisin oleva kohina ei häirinnyt merkittävästi ICA-tuloksia. Korkeadimensioinen ICA tarjosi paremman erottelun signaalilähteille, paljasti lepotilaverkostojen modulaarisen rakenteen ja määritti erityisen poikkeaman autismin kirjon oireyhtymän populaatiossa. ICA:n havaittiin olevan soveltuva täyseksploratiiviselle analyysille ajassa ja avaruudessa; tulos viittaa toiminnallisen kytkennällisyyden muutoksiin kallon läpäisevän kirkasvalostimulaation aikaansaamana.
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Eliminating propositional attitudes concepts / Pourquoi éliminer les concepts d'attitudes propositionnelles?

Bantegnie, Brice 03 September 2015 (has links)
Dans cette thèse je défends l'élimination des concepts d'attitudes propositionnelles. Dans le premier chapitre, je présente les thèses éliminativistes en philosophie de l'esprit et des sciences cognitives contemporaines. Il y a deux types d'éliminativisme: le matérialisme éliminatif et l'éliminativisme des concepts. Il est possible d'éliminer les concepts soit des théories naïves soit des théories scientifiques. L'éliminativisme à propos des concepts d'attitudes propositionnelles que je défends requière le second type d'élimination. Dans les trois chapitres suivants je donne trois arguments en faveur de cette thèse. Je commence par soutenir que la théorie interventionniste de la causalité ne fonde pas nos jugements de causalité mentale. Ensuite je montre que nos concepts d'attitudes propositionnelles ne sont pas des concepts d'espèces naturelles car ils groupent ensemble les états des différents modules d'une architecture massivement modulaire, la thèse de modularité massive faisant partie, je l'affirme, de notre meilleur programme de recherche. Finalement, mon troisième argument repose sur l’élimination du concept de contenu mental de nos théories. Dans les deux derniers chapitres de la thèse, je défends ce dernier argument. Tout d'abord, je réfute l'argument du succès selon lequel étant donné que les psychologues emploient le concept de contenu mental et ce faisant produisent de la bonne science ce concept ne devrait pas être éliminé. Ensuite je rejette une autre façon d'éliminer ce concept, celle choisie par les théoriciens de la cognition étendue. Pour cela je réfute le meilleur argument qui a été donné en faveur de cette thèse: l'argument du système. / In this dissertation, I argue for the elimination of propositional attitudes concepts. In the first chapter I sketch the landscape of eliminativism in contemporary philosophy of mind and cognitive science. There are two kinds of eliminativism: eliminative materialism and concept eliminativism. One can further distinguish between folk and science eliminativism about concepts: whereas the former says that the concept should be eliminated from our folk theories, the latter says that the concept should be eliminated form our scientific theories. The eliminativism about propositional attitudes concepts I defend is a species of the latter. In the next three chapters I put forward three arguments for this thesis. I first argue that the interventionist theory of causation cannot lend credit to our claims of mental causation. I then support the thesis by showing that propositional attitudes concepts aren't natural kind concepts because they cross-cut the states of the modules posited by the thesis of massive modularity, a thesis which, I contend, is part of our best research-program. Finally, my third argument rests on science eliminativism about the concept of mental content. In the two last chapters of the dissertation I first defend the elimination of the concept of mental content from the success argument, according to which as psychologists produce successful science while using the concept of mental content, the concept should be conserved. Then, I dismiss an alternative way of eliminating the concept, that is, the way taken by proponents of extended cognition, by refuting what I take to be the best argument for extended cognition, namely, the system argument.
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Sobre o uso da gramática de dependência extensível na geração de língua natural: questões de generalidade, instanciabilidade e complexidade / On the application of extensible dependency grammar to natural language generation: generality, instantiability and complexity issues

Jorge Marques Pelizzoni 29 August 2008 (has links)
A Geração de Língua Natural (GLN) ocupa-se de atribuir forma lingüística a dados em representação não-lingüística (Reiter & Dale, 2000); a Realização Lingüística (RL), por sua vez, reúne as subtarefas da GLN estritamente dependentes das especificidades da língua-alvo. Este trabalho objetiva a investigação em RL, uma de cujas aplicações mais proeminentes é a construção de módulos geradores de língua-alvo na tradução automática baseada em transferência semântica. Partimos da identificação de três requisitos fundamentais para modelos de RL quais sejam generalidade, instanciabilidade e complexidade e da tensão entre esses requisitos no estado da arte. Argumentamos pela relevância da avaliação formal dos modelos da literatura contra esses critérios e focalizamos em modelos baseados em restrições (Schulte, 2002) como promissores para reconciliar os três requisitos. Nesta classe de modelos, identificamos o recente modelo de Debusmann (2006) Extensible Dependency Grammar (XDG) e sua implementação - o XDG Development Toolkit (XDK) - como uma plataforma especialmente promissora para o desenvolvimento em RL, apesar de jamais utilizada para tal. Nossas contribuições práticas se resumem ao esforço de tornar o XDK mais eficiente e uma formulação da disjunção inerente à lexicalização adequada à XDG, demonstrando suas potenciais vantagens numa sistema de GLN mais completo / Natural Language Generation (NLG) concerns assigning linguistic form to data in nonlinguistic representation (Reiter & Dale, 2000); Linguistic Realization (LR), in turn, comprises all strictly target language-dependent NLG tasks. This work looks into RL systems from the perspective of three fundamental requirements - namely generality, instantiability, and complexity and the tension between them in the state of the art. We argue for the formal evaluation of models against these criteria and focus on constraint-based models (Schulte, 2002) as tools to reconcile them. In this class of models we identify the recent development of Debusmann (2006) - Extensible Dependency Grammar (XDG) - and its implementation - the XDG Development Toolkit (XDK) - as an especially promising platform for RL work, in spite of never having been used as such. Our practical contributions comprehend a successful effort to make the XDK more efficient and a formulation of lexicalization disjunction suitable to XDG, illustrating its potential advantages in a full-fledged NLG system
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Nová generace IPFIX kolektoru / A New Generation of an IPFIX Collector

Huták, Lukáš January 2018 (has links)
This master's thesis addresses processing of flow monitoring records from a point of view of an IPFIX collector. It analysis the current solution of the modular collector, which went through considerable historical development, and focuses on revealing its strengths and weaknesses. Based on acquired knowledge, a new collector is designed. The new solution, which significantly modifies individual components for processing of flow records, focuses on high throughput and adds missing functionalities. The document also compares performance of both generations and the new collector clearly dominates.
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Realizace webového modulárního systému / Implementation of modular web based application

Suchý, Petr January 2008 (has links)
Diploma thesis Implementation of modular web based application deals with web modular systems. The aim of web modular system is to allow creating universal web presentation without necessity of creation new systems. Diploma thesis is devided into couple parts. Advantages of modular solution of web systems are highlighted in the first part and after that is analyzed the current situation of this problem. In the next part is designed own web modular system above all its kernel, modules and data model. In the final part is described own implementation of own designed system. The most stress is layed on security of the system. In the conclusion is summed up own solution and its most advantages.

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