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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.
141

Interação entre o grupamento parafacial/núcleo retrotrapezóide e a região de kölliker-fuse na modulação do padrão respiratório. / Interaction between the retrotrapezoid nucleus/parafacial region and the kölliker-fuse area in the modulation of the respiratory pattern.

Elvis Viana de Lucena 09 June 2015 (has links)
O padrão respiratório é dividido em 4 fases: pré-inspiração (PrI), inspiração (I), pós-inspiração ou fase 1 da expiração (PI/E1) e a expiração ativa (E2), que são moduladas por áreas encefálicas. Diante disso, o objetivo do presente estudo foi verificar o envolvimento dessa região no controle da atividade PrI e PI em ratos Wistar adultos (270-320 g, n = 5/grupo). Foram registradas a pressão arterial média (PAM), atividade eletromiográfica dos músculos genioglosso (GGEMG), diafragma (DiaEMG) e abdominal (AbdEMG) e a atividade elétrica do nervo vago em ratos ventilados artificialmente e anestesiados com uretano. A injeção unilateral de NMDA (5 pmol/50 nl) no pFRG/RTN de animais anestesiados foi capaz de promover um aumento da PAM (13 ± 6 mmHg), da atividade elétrica dos músculos GGEMG (21 ± 3%), do DiaEMG (25 ± 5%), além de gerar a atividade expiratória observada no registro da atividade do AbdEMG. Adicionalmente, a estimulação do pFRG/RTN promoveu um aumento da atividade pós-inspiratória (57 ± 9%). A injeção bilateral de muscimol na região de KF eliminou a atividade do GGEMG (2 ± 2%), mas apenas reduziu a atividade do DiaEMG (12 ± 2%) e do AbdEMG (111 ± 13%) induzida pela injeção de NMDA no RTN. Além disso, a inibição da região do KF foi capaz de eliminar o aumento da atividade do GGEMG (6 ± 4 vs. salina: 47 ± 9%) após a hipercapnia (10% CO2). A injeção de muscimol no KF apenas reduziu a atividade do DiaEMG (25 ± 6 vs. salina: 43 ± 8%) e a atividade do AbdEMG (213 ± 23 vs. salina: 335 ± 18%) induzidas pela hipercapnia. Nossos resultados mostram que a região do pFRG/RTN, além de estar envolvida no controle da atividade I e E2, tem uma participação na geração da atividade pré e pós-inspiratória e que essas respostas respiratórias são moduladas pela atividade de KF. / Breathing pattern is divided into 4 phases: pre-inspiration (PrI), inspiration (I), post-inspiration or first phase of expiration (PI/E1) and the active expiration (E2), and this phases are controlled by the central nervous system . Thus, the aim of this study was to investigate the involvement of this region in the control of PrI and PI activity in adult male Wistar rats (270-320 g, n = 5/group). Mean arterial pressure (MAP), the electromyographic activity of the genioglossus muscles (GGEMG), diaphragm (DiaEMG) and abdominal (AbdEMG) and the electrical activity of the vagus nerve were recorded in rats artificially ventilated and urethane anesthetized. Unilateral injection of NMDA (5 pmol/50 nl) in the pFRG/RTN of anesthetized animals was able to produce an increase in MAP (13 ± 6 mmHg), GGEMG (21 ± 3%), DiaEMG (25 ± 5%), and elicit an expiratory activity in the AbdEMG. In addition, pFRG/RTN stimulation increase post-inspiratory activity (57 ± 9%). Bilateral injection of muscimol (100 pmol/50 nl) into the KF eliminated the GGEMG (2 ± 2%), but only reduced the DiaEMG (12 ± 2%) and AbdEMG (111 ± 13%) induced by NMDA injection into the pFRG/RTN. Muscimol bilaterally into the KF was able to eliminate GGEMG (6 ± 4 vs. saline: 47 ± 9%) after hypercapnia (10% CO2). Muscimol into the KF reduced the DiaEMG (25 ± 6 vs. saline: 43 ± 8%) and AbdEMG (213 ± 23 vs. saline: 335 ± 18%) produced by hypercapnia. The results of the present study showed for the first time that the pFRG/RTN region it is not only involved in the control of inspiration and expiration, but shows to have a role in the pre- and post-inspiratory activity. Moreover, our work also presents evidence that these respiratory responses are modulated by KF network.
142

Localisation et estimation basées modèle d’un objet ellipsoidal avec le sens électrique artificiel / Model based localization and estimation of an ellipsoidal object using artificial electric sense

Lanneau, Sylvain 04 October 2017 (has links)
Le but de cette thèse est de contribuer à la perception sous-marine pour des applications de robotique grâce à un champ électrique. Nous proposons de nouvelles méthodes pour l’inspection, la localisation et l’estimation de forme d’un objet ellipsoïdal en utilisant un capteur inspiré des poissons faiblement électriques. Premièrement, nous montrons que l’objet peut être détecté et que son matériau et sa position par rapport à l’axe du capteur peuvent être discriminés en utilisant de simples détections de seuils sur les courants mesurés. Ensuite, nous proposons l’implémentation successive de trois lois de contrôle réactives permettant au capteur de se diriger vers l’objet et d’effectuer une révolution autour de celui-ci en suivant ses frontières. Puis, nous utilisons l’algorithme MUSIC afin de localiser le centre de l’objet. Enfin, les paramètres géométriques de l’objet et son orientation sont estimés grâce à une méthode d’optimisation basée sur les moindres carrés et sur l’inversion du modèle analytique du tenseur de polarisation d’un objet ellipsoïdal. Nous montrons que ces algorithmes fonctionnent en conditions expérimentales. Pour les algorithmes de localisation et d’estimation de forme, des techniques impliquant des déplacements du capteur sont proposées, afin de réduire significativement les imprécisions dues aux écarts entre le modèle et les mesures de courant. / The aim of this thesis is to contribute to the underwater perception for robotics applications using an electric field. We propose new methods for the inspection, the localization and the shape estimation of an ellipsoidal object using a sensor inspired by the weakly electric fish. Firstly, we show that the object can be detected and its material and position relative to the sensor axis discriminated, using simple threshold detections on the measured currents. Then, we propose the successive implementations of three reactive control laws allowing the sensor to head for the object and revolve around it by following its boundaries. After that, we use the MUSIC algorithm in order to localize the object’s center. Finally, the geometrical parameters of the object and its orientation are estimated thanks to an optimization algorithm based on the least squares method and the inversion of the analytical model of the polarization tensor of an ellipsoidal object. We show that these algorithms can be experimentally implemented. For the localization and the shape estimation algorithms, some additional techniques involving sensor movements are proposed in order to significantly reduce the imprecisions due to the gap between the model and the actual currents’ measurements.
143

Conflit et complicité : la communauté des femmes chez Clarice Lispector

Antonaci Gama, Carolina 08 1900 (has links)
S’il y a deux mots qui nous appellent encore, nous convoquent, nous incitent à rêver et en même temps résistent à bien des égards à livrer leur « vérité », ce sont bien les mots « communauté » et « femme ». Cette thèse s’efforce de les rapprocher, de les garder dans la proximité et ce à partir des écrits de Clarice Lispector. Étant donné que l’oeuvre de l’écrivaine brésilienne, composée dans sa grande majorité de personnages et narrateurs féminins, met souvent en scène des face-à-face féminins, nous examinons comment ces rencontres témoignent d’une possible communauté des femmes. Cependant, tel qu’annoncé dans le titre de cette étude, la communauté des femmes dont il est question dans l’oeuvre de Lispector est celle qui existe sporadiquement oscillant entre conflit et complicité. Pour tenter de donner une forme et un vocabulaire à une telle communauté des femmes, nous parcourons les principales théories de la communauté, notamment celles développées par Jean-Luc Nancy, Maurice Blanchot, Jacques Derrida et Roland Barthes ainsi que certaines théories du féminisme. Ensuite, nous explorons des notions qui « provoquent » l’irruption de la communauté des femmes comme la répétition, le rythme, l’inspiration et le don. En fin de compte, ce résumé aurait pu n’avoir qu’une phrase, une seule phrase qui résume toute la thèse : la communauté de celles qui n’ont pas de communauté ou pas une communauté comme les autres. / If there are two words that still call us, summon us, make us dream and at the same time resist in many ways to deliver their "truth", they are community and woman. This thesis strives to bring them closer, to keep them in proximity in referring to the writings of Clarice Lispector. Since the work of the Brazilian writer, composed largely of female characters and narrators, often features women's face-to-face, we examine how these encounters reflect a possible community of women. However, as announced in the title of this study, the community of women in question in Lispector's work is one that exists sporadically oscillating between conflict and complicity. In an attempt to give form and vocabulary to such a community of women, we go through the main theories of the community, especially those developed by Jean-Luc Nancy, Maurice Blanchot, Jacques Derrida and Roland Barthes as well as some theories of feminism. Then we explore concepts that "provoke" the emergence of the community of women as repetition, rhythm, inspiration and gift. Ultimately, this summary could have had only one sentence, one sentence that sums up the whole thesis: the community of women without community or not a community like the others.
144

Synthèse de complexes de cuivre bio-inspirés pour la réduction catalytique de l'oxyde nitreux et du dioxygène / Bio-inspired copper complexes syntheses for catalytic nitrous oxide and dioxygen reduction

Mangue, Jordan 05 December 2018 (has links)
N2O est le troisième plus important gaz à effet de serre ainsi qu’un des principaux gaz responsables de la dégradation de la couche d’ozone. Une approche bio-inspirée de la N2Oréductase (N2Or), enzyme réduisant N2O via un site actif comportant quatre ions cuivre pontés par un atome de soufre, aide au design de nouveaux systèmes. Six complexes à valences mixtes comportant un motif Cu2(µ-S) considéré comme minimum pour avoir une activité ont alors été synthétisés. Il a été démontré que la structure de ces centres métalliques est affectée par le solvant utilisé. Dans un solvant non coordinant comme l’acétone, tous les complexes possèdent une liaison intermétallique et une valence délocalisée à température ambiante. En revanche en solvant coordinant, la coordination de molécules d’acétonitrile rend impossible la formation de liaison intermétallique et localise la valence.Pour tester l’activité N2Or de ces complexes, un prototype permettant un bullage constant en cuve UV a été conçu. L’objectif est de mettre au point une réduction catalytique de N2O en utilisant un réducteur sacrificiel et une source de proton. Le gaz utilisé lors des tests semble cependant contenir une faible quantité de O2 empêchant la caractérisation des activités. Une optimisation visant à purifier N2O avant les tests est en cours.Par ailleurs, les réductions de O2 à deux électrons pour former H2O2 (un oxydant doux) et à quatre électrons pour former H2O (réaction utilisée dans les piles à combustibles) en font un domaine attractif. Il a été démontré que tous les complexes synthétisés lors de ces travaux sont capables de réduire catalytiquement O2 dans l’acétone et que seulement celui sans position échangeable est actif dans l’acétonitrile. Ce dernier a de plus montré une capacité à changer de sélectivité (H2O2 vs H2O) en fonction de la concentration en réducteur sacrificiel utilisé. / N2O is the third most important global warming gas and one of the most aggressive gas against ozone layer. A bio-inspired approach from N2Oreductase (N2Or), enzyme catalysing the two electron reduction of N2O with a four sulfur-bridged copper ions centre, helps for the design of new systems. Six mixed valent copper complexes containing the minimum Cu2(µ-S) core were then synthetized. It has been shown that these structures are affected by solvents in solution. Indeed, in a non-coordinating solvent like acetone, all these complexes have an intermetallic bond and a delocalized valence at room temperature. However in a coordinating solvent, the acetonitrile coordination makes it impossible to form a Cu-Cu bond and localize the valences.To test the N2Or activity, a prototype allowing a constant N2O bubbling in a UV cuve using a closed system was designed. The aim is to develop a catalytic reduction using sacrificial reductant and proton source. However, the gas bottle used for activity tests seems to contain a small amounts of O2 preventing results interpretation. The aim is now to optimize the prototype by adding a system that can purify N2O before activity tests.In a second time, the O2 reduction using two electrons to produce H2O2 (a soft oxidant) or four electron to produce H2O (useful in fuel cells) are of interest. It has been shown that all these new complexes are capable of catalytically reducing O2 in acetone and that only the one without exchangeable position can do it in acetonitrile. The latter has also demonstrate its ability to change its selectivity to produce H2O2 or H2O by changing the sacrificial reductant concentration. These results bring interesting insights for O2 activation with bio-inspired copper complexes.
145

Intrinsic motivation mecanisms for incremental learning of visual saliency / Apprentissage incrémental de la saillance visuelle par des mécanismes de motivation intrinsèque

Craye, Céline 03 April 2017 (has links)
La conception de systèmes de perception autonomes, tels que des robots capables d’accomplir un ensemble de tâches de manière sûre et sans assistance humaine, est l’un des grands défis de notre siècle. Pour ce faire, la robotique développementale propose de concevoir des robots qui, comme des enfants, auraient la faculté d’apprendre directement par interaction avec leur environnement. Nous avons dans cette thèse exploré de telles possibilités en se limitant à l’apprentissage de la localisation des objets d’intérêt (ou objets saillants) dans l’environnement du robot.Pour ce faire, nous présentons dans ces travaux un mécanisme capable d’apprendre la saillance visuelle directement sur un robot, puis d’utiliser le modèle appris de la sorte pour localiser des objets saillants dans son environnement. Cette méthode a l’avantage de permettre la création de modèles spécialisés pour l’environnement du robot et les tâches qu’il doit accomplir, tout en restant flexible à d’éventuelles nouveautés ou modifications de l’environnement.De plus, afin de permettre un apprentissage efficace et de qualité, nous avons développé des stratégies d’explorations basées sur les motivations intrinsèques, très utilisées en robotique développementale. Nous avons notamment adapté l’algorithme IAC à l’apprentissage de la saillance visuelle, et en avons conçu une extension, RL-IAC, pour permettre une exploration efficace sur un robot mobile. Afin de vérifier et d’analyser les performances de nos algorithmes, nous avons réalisé des évaluations sur plusieurs plateformes robotiques dont une plateforme fovéale et un robot mobile, ainsi que sur des bases de données publiques. / Conceiving autonomous perceptual systems, such as robots able to accomplish a set of tasks in a safe way, without any human assistance, is one of the biggest challenge of the century. To this end, the developmental robotics suggests to conceive robots able to learn by interacting directly with their environment, just like children would. This thesis is exploring such possibility while restricting the problem to the one of localizing objects of interest (or salient objects) within the robot’s environment.For that, we present in this work a mechanism able to learn visual saliency directly on a robot, then to use the learned model so as to localize salient objects within their environment. The advantage of this method is the creation of models dedicated to the robot’s environment and tasks it should be asked to accomplish, while remaining flexible to any change or novelty in the environment.Furthermore, we have developed exploration strategies based on intrinsic motivations, widely used in developmental robotics, to enable efficient learning of good quality. In particular, we adapted the IAC algorithm to visual saliency leanring, and proposed an extension, RL-IAC to allow an efficient exploration on mobile robots.In order to verify and analyze the performance of our algorithms, we have carried out various experiments on several robotics platforms, including a foveated system and a mobile robot, as well as publicly available datasets.
146

Vad är inspiration och hur fungerar den? : En granskning av amatörskapares relationer till inspiration / What is inspiration and how does it work? : A study of creative amateurs' relations to inspiration

Thorén, Filip, Olsson-Hovstadius, Olof January 2022 (has links)
What does inspiration mean to creative amateurs? Inspiration as a concept has been hard to define in information science terms. Several theories of information-seeking behavior have also been proposed to be applicable to inspiration-seeking, but have not seen empirical testing. While previous researchers on inspiration have mostly focused on artists and designers, this essay has studied amateurs and makers engaged in creative hobbies. Based on a survey distributed to study circles organized under Swedish adult educational associations, the grounded theory analysis indicated that inspiration is important as a feeling of motivation, joy, well-being and productivity, a source of ideas, and a driving force in the creative process. The results of the survey also showed that more passive information-seeking strategies, such as serendipitous encounters, browsing, and social interaction, were more commonly associated with finding inspiration than active strategies, such as systematic searches and question-based seeking, within the group. The responses showed that the respondents’ perceptions of inspiration were somewhat idiosyncratic, and future research based on individual or focus group interviews would be needed to explore the more ambiguous concepts and answers gleaned in this study. This is a two years master's thesis in Library and information science.
147

ENTDECKUNG : Sichtbarmachung einer Symbiose - Natur + Beton: Katalog zur Ausstellung: Exhibition Catalog

SFB/Transregio 280 01 November 2023 (has links)
Der Alleskönner Beton ist grundsätzlich einfach, schnell und kostengünstig in der Herstellung. Er kann nahezu jede beliebige Form annehmen und wird als einziger Baustoff auch flächendeckend in Entwicklungs- und Schwellenländern eingesetzt. Beton hat aber auch seine Schattenseiten. Die Zementherstellung geht mit einem enormen CO2-Ausstoß einher. Zudem wird eine große Menge natürlicher Ressourcen, teils unnötig, verbraucht. Dennoch werden wir auch in Zukunft nicht ohne Beton auskommen, aber wir haben es in der Hand, den Betonbau nachhaltig zu verbessern. Der SFB/Transregio 280 hat zum Ziel, innovative Konzepte und Strategien für ein intelligentes Bauen mit Carbonbeton zu entwickeln. Damit dies gelingt, sind neue Denkweisen, die Änderung bewährter Denkmuster und das Zunutzemachen verschiedenster Inspirationsquellen unabdingbar. Aus diesem Grund hat der SFB/TRR 280 Kunstschaffende dazu eingeladen, sich von den Themen des Sonderforschungsbereiches inspirieren zu lassen. Ziel des Wettbewerbs war es darzustellen, dass Carbonbeton als Produkt von Wissenschaft und Technik vielfältige Beziehungen zu Kunst und Natur aufweist. Was wird sichtbar? Was bleibt dem Forschenden und was dem Außenstehenden verborgen? Wie lassen sich Natur und Carbonbeton als Kunstobjekt verbinden? Im vorliegenden Band wurden alle Einreichungen und das Making-off der prämierten Ideen zusammengestellt.:Wettbewerb - Entdeckung - Ziel 4 Ausschreibung - Ausstellung - Organisation 5 Die Jury 6 1. Platz - Leporello : Suggestion von Bewegung in statischer Präsenz 9 2. Platz - Fibonaccibikini : Hyperbolische Geometrien im Raum 13 3. Platz - Hülle : Ein poetisches Umschreiben der Leere 17 Register: 25 Graukarten 20 Flügel 22 Körperbau : Videokunst / Videoperformance 24 Asymmetrische Ausblicke : Ruhige Ausschnitte versus dynamische Form 26 Trashtopia : Eine Animation 28 Great Barriere Reef 2023 30 Terra : Zerstörung und Erneuerung 32 Nobjects . Eine Serie 34 Luftstütze : Pflanzeninspiriert 36 Die Natur im Inneren : Skulptur aus Carbonbeton 38 Aus dem Boden am Fluss 40 Chaperon 42 Supernatural - Polar 44 Botanik brut : Fotografischer Beton 46 Würfelzwilling 48 Betonkoeppe 50 Voyager 52 Forme perdu 54 Beton durchwachsen : Ein Kustobjekt aus Beton, das der Natur Raum gibt 56 Bonboo 58 QY03 60 / The all-rounder concrete is basically simple, fast and inexpensive to produce. Concrete components can assume and conserve almost any shape. It is the only building material used extensively also in developing and emerging countries. However, concrete also has its downsides. Cement production is associated with enormous CO2 emissions. In addition, a large amount of natural resources is consumed, sometimes unnecessarily. Nevertheless, we will not be able to build without concrete in the future, but we have it in our hands to improve concrete construction sustainably. The Collaborative Research Centre/Transregio 280 (in short: CRC/TRR 280) aims to develop innovative concepts and strategies for intelligent construction with carbon-reinforced concrete. For this to succeed, new ways of thinking, changing proven patterns of thought and tapping into a wide variety of sources of inspiration are essential. For this reason, we invited artists to be inspired by the research topics of CRC/TRR 280. The aim of the competition was to show that carbon-reinforced concrete, as a product of science and technology, has diverse relationships with art and nature. What becomes visible? What remains hidden to the researcher and what to the outsider? How can nature and carbon-reinforced concrete be combined as art objects? In this catalog, all submissions and the making of the award-winning ideas have been compiled.:Wettbewerb - Entdeckung - Ziel 4 Ausschreibung - Ausstellung - Organisation 5 Die Jury 6 1. Platz - Leporello : Suggestion von Bewegung in statischer Präsenz 9 2. Platz - Fibonaccibikini : Hyperbolische Geometrien im Raum 13 3. Platz - Hülle : Ein poetisches Umschreiben der Leere 17 Register: 25 Graukarten 20 Flügel 22 Körperbau : Videokunst / Videoperformance 24 Asymmetrische Ausblicke : Ruhige Ausschnitte versus dynamische Form 26 Trashtopia : Eine Animation 28 Great Barriere Reef 2023 30 Terra : Zerstörung und Erneuerung 32 Nobjects . Eine Serie 34 Luftstütze : Pflanzeninspiriert 36 Die Natur im Inneren : Skulptur aus Carbonbeton 38 Aus dem Boden am Fluss 40 Chaperon 42 Supernatural - Polar 44 Botanik brut : Fotografischer Beton 46 Würfelzwilling 48 Betonkoeppe 50 Voyager 52 Forme perdu 54 Beton durchwachsen : Ein Kustobjekt aus Beton, das der Natur Raum gibt 56 Bonboo 58 QY03 60
148

The doctrine of scripture and the providence of God / Roydon James John Frost

Frost, Roydon James John January 2015 (has links)
Ever since the Reformation the providence of God has been variously applied in the doctrine of scripture. In the Reformed and Protestant Orthodox traditions, and in the context of polemic surrounding the nature of scripture that has prevailed down the centuries, providence has always played an important supporting role. In the case of inspiration, it is applied to the preparation of God’s spokesmen. In the case of canon, God is understood to have supervised the reception of just those books He intended for His church. In the case of textual transmission, ‘a singular act of God’s providence’ has preserved the scriptures through time. Thus, providence undergirds the Reformed doctrine of scripture. It functions almost at the level of presupposition. However, such usage is seldom justified, and this raises the question of warrant. The Bible itself must be revisited to determine if the application of providence to scripture in Reformed Dogmatics is legitimate by its own standard of Sola Scriptura. A survey and exegesis of a number of important passages confirms that it is. It shows that the application of providence in the doctrine of scripture is not only justified, but is also helpful to a better understanding of the nature of God and His written Word. / MA (Dogmatics), North-West University, Potchefstroom Campus, 2015
149

The doctrine of scripture and the providence of God / Roydon James John Frost

Frost, Roydon James John January 2015 (has links)
Ever since the Reformation the providence of God has been variously applied in the doctrine of scripture. In the Reformed and Protestant Orthodox traditions, and in the context of polemic surrounding the nature of scripture that has prevailed down the centuries, providence has always played an important supporting role. In the case of inspiration, it is applied to the preparation of God’s spokesmen. In the case of canon, God is understood to have supervised the reception of just those books He intended for His church. In the case of textual transmission, ‘a singular act of God’s providence’ has preserved the scriptures through time. Thus, providence undergirds the Reformed doctrine of scripture. It functions almost at the level of presupposition. However, such usage is seldom justified, and this raises the question of warrant. The Bible itself must be revisited to determine if the application of providence to scripture in Reformed Dogmatics is legitimate by its own standard of Sola Scriptura. A survey and exegesis of a number of important passages confirms that it is. It shows that the application of providence in the doctrine of scripture is not only justified, but is also helpful to a better understanding of the nature of God and His written Word. / MA (Dogmatics), North-West University, Potchefstroom Campus, 2015
150

Towards bio-inspired photonic vapour sensors

Starkey, Timothy Andrew January 2014 (has links)
Many highly-evolved bio-photonic structures, which tailor the propagation of light by coherent optical scattering, have been investigated. These natural designs, which have many diverse ecological functions, are becoming increasingly studied as sources of innovation and inspiration for a range of scientific, technological, and commercial applications. The brilliant blue colour reflected from the scales of the Morpho butterfly is just one example of nature’s ability to manipulate light and colour strongly. In this thesis, the photonic structure present in the scales of the Morpho butterfly is investigated as a source of bio-inspiration in the pursuit of high- performance photonic vapour sensors. The intention of this is to outperform classical sensor approaches which traditionally suffer from poor selectivity between chemical species. By measuring the change in reflectance from the iridescent scales of the Morpho butterfly, both a sensitive and, critically, a selective response to chemical vapours can be obtained. Here, the origin of this unique multivariable vapour-induced optical response is investigated, and this biological template is further explored as a source of innovation for the mature field of chemical sensing. By using synergy between experimental and theoretical techniques, a mechanism for the sensitive and selective response of the Morpho butterfly’s scales to different chemical vapour environments is elucidated. This mechanism arises from combined chemical and physical effects within the photonic nanostructure. Following this, demonstrations of this biological template’s vapour response attributes, which have large and desirable diversity in the optical responses, are made. These response attributes are visualised in the spectral changes associated with optical excitation conditions, such as from different angles and polarisation states, and also in the temporal response profiles. Finally, theoretical sensor designs that outperform the Morpho scales are described. Simple principles that might improve the currently unacceptable levels of selectivity in contemporary sensor implementations are outlined and the vapour response of a Morpho-inspired photonic structure is presented.

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