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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.
111

Generation of uncorrelated photon-pairs in optical fibres

Cohen, Offir January 2010 (has links)
Light, which is composed of discrete quanta, or photons, is one of the most fundamental concepts in physics. Being an elementary entity, the behaviour of photons is governed by the rules of quantum mechanics. The ability to create, manipulate and measure quantum states of light is not only useful in foundational tests of quantum theory, but also in a wide range of quantum technologies – which aim to utilize non-classical properties of quantum systems to perform tasks not possible with classical resources. Only recently has it been possible to control the properties of number states of light, which have a fixed photon-number. Two-photon states are central to testing fundamental physical theories (such as locality and reality) and the implementation of quantum information technologies. The versatility of photon-pair states is en- abled by the potential entanglement properties it can posses. Thus controlling the correlations between photons is crucial to both pure and applied physics. To produce a single photon, a photon-pair state can be used. Detection of one photon indicates its twin’s existence. Many applications, such as optical quantum computation, require pure indistinguishable single photons. Heralding single pho- tons from a photon-pair will, in general, produce single photons in a mixed quantum state due to correlations within the pair. A common approach to creating photon-pairs is through the nonlinear sponta- neous four-wave mixing interaction in optical fibres. This thesis presents a theoreti- cal and experimental implementation of a scheme to tailor the spectral correlations within the pairs. Emphasis is placed on engineering the two-photon state such that they are completely uncorrelated. Spatial entanglement is naturally avoided due to the discrete nature of the optical fibre modes. Spectral correlations are eliminated by careful choice of dispersion characteristics and conditions. The purity of the photons generated by this scheme is demonstrated by means of two-photon inter- ference from independent sources. We measure a purity of (85.9 ± 1.6)% with no spectral filtering, exhibiting the usefulness of this source for quantum technologies and applications.
112

Upplevelser av ett missfall : En litteraturstudie

Nord, Frida, Staf, Kristin January 2017 (has links)
Bakgrund: Av alla graviditeter slutar 10-20% med ett missfall, vilket betyder att det är vanligt förekommande och drabbar många kvinnor. Ett missfall kan innebära en väldigt traumatisk upplevelse för den drabbade och är både psykiskt och fysiskt påfrestande.   Syfte: Syftet med litteraturstudien är att beskriva kvinnors upplevelser av missfall.   Metod: Litteraturstudie där resultatet baseras på 10 vetenskapliga artiklar baserade på en kvalitativ ansats.   Resultat: Vid ett missfall upplevde kvinnorna i studierna ofta att vårdpersonal gav för lite information och hade bristande förståelse. Mer psykosocialt stöd var en återkommande önskan, då de sällan blev erbjudna det. Missfallet innebar mer än att förlora ett framtida barn. Det var en komplex situation, där kvinnan drabbades av både fysisk och psykisk smärta. Känslor såsom att förlora kontrollen, att skuldbelägga sig själv, oro och rädsla inför framtiden var ofta förekommande. Sorgen över vad de kunde haft var något som kunde vara i flera år efter missfallet. Att få bearbeta sorgen visade sig vara en väldigt viktig del för de flesta kvinnorna.   Slutsats: Sorg är något som de flesta kvinnor upplever efter ett missfall och många av dem efterfrågar mer stöd och hjälp i hanteringen av sorgearbetet. Att drabbas av psykisk ohälsa, såsom depression och ångest är vanligt förekommande efter ett missfall. Genom att erbjuda alla drabbade kvinnor psykosocialt stöd i anslutning till missfallet kan psykisk ohälsa och onödigt lidande förebyggas. Det finns ett behov av ett bättre bemötande samt mer information från vårdpersonal. Eftersom brist på information kan leda till att kvinnan skuldbelägger sig själv bör detta prioriteras. Sjukvårdspersonal behöver mer kunskap gällande upplevelser av missfall för att kunna ge en tillfredsställande omvårdnad där kvinnan känner sig trygg och väl bemött. Det bör dock tas hänsyn till att allas upplevelser av ett missfall är individuellt och vården bör därför anpassas därefter. / Background: Of all pregnancies, 10-20% end with miscarriage, which means that it is a common matter and affects many. It can be a very traumatic experience and the effects it has on women can be both mental and physical.   Purpose: The purpose of this literary study is to describe women's experiences of miscarriage.   Method: The method of the research is a literary study, which is based on 10 original articles, with a qualitative approach.   Results: When a miscarriage occurred, women often felt that the care staff offered limited information and had a lack of understanding. More psychosocial support was a recurring desire as the women seldom felt that they were provided with it. The miscarriage meant more to them than losing a future child. It was a complex situation where the woman was in both physical and mental pain. Emotions such as lack of control, self-blame, anxiety, fearing for the future and sorrow were frequent. Grieving over what they could have had was something that could be experienced over several years after the miscarriage. Processing the grief was a very important part for most women.    Conclusion: Grief is something that most women experience after a miscarriage and many of them are asking for more support and help in dealing with grief. To suffer from mental illness, such as depression and anxiety are common after a miscarriage. By offering all affected women psychosocial support after the miscarriage, mental illness and unnecessary suffering can be prevented. There is a need for a better refutation as well as more information from health professionals. Because of the lack of information woman sometimes blames themselves, therefore this should be a priority. Healthcare professionals need more knowledge regarding experiences of miscarriage in order to provide adequate care where the woman can feel safe and be treated well. However, it should be taken into account that everyone's experience of a miscarriage are individually and care should therefore be adjusted accordingly.
113

Probabilistic models for studying variability in single-neuron and neuronal ensemble activity / Modèles probabilistes pour l'étude de la variabilité dans l'activité de neurones individuels et d'ensembles de neurones

Ponce Alvarez, Adrián 13 December 2010 (has links)
Une des caractéristiques les plus singulières de l’activité corticale est son degré élevé de variabilité. Ma thèse dedoctorat s’est focalisée sur l’étude de (i) l’irrégularité des intervalles entre potentiels d’action (PAs)successivement émis par un neurone, et (ii) la variabilité dans l’évolution temporelle de l’activité d’un ensemblede neurones. Premièrement, j’ai étudié l’irrégularité des neurones enregistrés dans le cortex moteur de singesmacaques performant une tâche d’estimation du temps et de préparation à l’action. J’ai montré que l’irrégularitén’est pas un paramètre libre de l’activité neuronale, contrairement au taux de PAs, mais est déterminée par lescontraintes structurelles des réseaux neuronaux. Deuxièmement, j’ai utilisé le modèle de Markov caché (MMC)pour analyser l’activité d’ensembles de neurones enregistrés dans plusieurs aires corticales, sensorielles etmotrices, de singes exécutant une tâche de discrimination tactile. J’ai montré que les processus sensoriels etdécisionnels sont distribués dans plusieurs aires corticales. Les résultats suggèrent que l’action et la décision surlaquelle elle est basée sont reliées par une cascade d’évènements non stationnaires et stochastiques. Finalement,j’ai utilisé le MMC pour caractériser l’activité spontanée d’un ensemble de neurones du cortex préfrontal d’unrat. Les résultats montrèrent que l’alternance entre les états UP et DOWN est un processus stochastique etdynamique. La variabilité apparaît donc aussi bien pendant l’activité spontanée que pendant le comportementactif et semble être contrainte par des facteurs structurels qui, à leur tour, contraignent le mode d’opération desréseaux neuronaux. / A hallmark of cortical activity is its high degree of variability. The present work focused on (i) the variability ofintervals between spikes that single neurons emit, called spike time irregularity (STI), and (ii) the variability inthe temporal evolution of the collective neuronal activity. First, I studied the STI of macaque motor corticalneurons during time estimation and movement preparation. I found that although the firing rate of the neuronstransmitted information about these processes, the STI of a neuron is not flexible and is determined by thebalance of excitatory and inhibitory inputs. These results were obtained by means of an irregularity measure thatI compared to other existing measures. Second, I analyzed the neuronal ensemble activity of severalsomatosensory and motor cortical areas of macaques during tactile discrimination. I showed that ensembleactivity can be effectively described by the Hidden Markov Model (HMM). Both sensory and decision-makingprocesses were distributed across many areas. Moreover, I showed that decision-related changes in neuronalactivity rely on a noise-driven mechanism and that the maintenance of the decision relies on transient dynamics,subtending the conversion of a decision into an action. Third, I characterized the statistics of spontaneous UP andDOWN states in the prefrontal cortex of a rat, using the HMM. I showed that state alternation is stochastic andthe activity during UP states is dynamic. Hence, variability is prominent both during active behavior andspontaneous activity and is determined by structural factors, thus rending it inherent to cortical organization andshaping the function of neural networks.
114

Fermion Mass Generation without Spontaneous Symmetry Breaking

Ayyar, Venkitesh January 2016 (has links)
<p>The conventional mechanism of fermion mass generation in the Standard Model involves Spontaneous Symmetry Breaking (SSB). In this thesis, we study an alternate mechanism for the generation of fermion masses that does not require SSB, in the context of lattice field theories. Being inherently strongly coupled, this mechanism requires a non-perturbative approach like the lattice approach.</p><p>In order to explore this mechanism, we study a simple lattice model with a four-fermion interaction that has massless fermions at weak couplings and massive fermions at strong couplings, but without any spontaneous symmetry breaking. Prior work on this type of mass generation mechanism in 4D, was done long ago using either mean-field theory or Monte-Carlo calculations on small lattices. In this thesis, we have developed a new computational approach that enables us to perform large scale quantum Monte-Carlo calculations to study the phase structure of this theory. In 4D, our results confirm prior results, but differ in some quantitative details of the phase diagram. In contrast, in 3D, we discover a new second order critical point using calculations on lattices up to size $ 60^3$. Such large scale calculations are unprecedented. The presence of the critical point implies the existence of an alternate mechanism of fermion mass generation without any SSB, that could be of interest in continuum quantum field theory.</p> / Dissertation
115

Étude moléculaire des étapes précoces de la symbiose actinorhizienne Casuarina-Frankia : analyse fonctionnelle des gènes de la plante hôte contrôlant l’infection / Molecular study of the early stages of actinorhizal symbiosis Casuarina-Frankia : functional analysis of the host plant genes controlling the infection

Benabdoun, Faïza Meriem 02 December 2012 (has links)
Étude moléculaire des étapes précoces de la symbiose actinorhizienne Casuarina-Frankia : analyse fonctionnelle des gènes de la plante hôte contrôlant l'infectionPlus de 80% des plantes peuvent établir une symbiose racinaire avec des champignons de l'ordre des Glomales et former des endomycorhizes à arbuscules (AM). En revanche, seules certaines espèces appartenant à dix familles d'angiospermes réunies dans le Clade des Eurosidées I peuvent établir une symbiose racinaire fixatrice d'azote. Il s'agit d'une part, des plantes de la famille des légumineuses (Fabacées) et de Parasponia associées à Rhizobium et d'autre part, des plantes actinorhiziennes associées à l'actinomycète Frankia. Comme chez les légumineuses, la symbiose actinorhizienne aboutit à la formation de nodosités (ou « nodules »), siège de la fixation d'azote par les bactéries. Cependant, contrairement aux nodules des légumineuses, le nodule actinorhizien présente une structure et un développement s'apparentant aux racines latérales. L'étude des nodosités actinorhiziennes est donc particulièrement intéressante tant pour rechercher les spécificités de cette symbiose, que pour déterminer quelles sont les caractéristiques communes avec les légumineuses. Nous avons étudié le rôle du gène CCaMK dans le processus symbiotique et l'organogenèse nodulaire chez l'arbre actinorhizien Casuarina glauca. CCaMK code pour une protéine kinase dépendante du calcium et de la calmoduline (« calcium and calmodulin dependent protein kinase »). Dans la cascade de signalisation conduisant à la nodulation et à la mycorhization chez les légumineuses, ce gène est positionné en aval des oscillations calciques (« calcium spiking ») qui ont lieu durant les premières étapes de l'interaction symbiotique. CCaMK jouerait un rôle dans la perception et le décodage des oscillations calciques, ainsi que leur transduction aux différents composants contrôlant les endosymbioses racinaires. Nous avons suivi l'expression spatio-temporelle de la fusion transcriptionnelle PromCgCCaMK::GUS au cours de la nodulation et montré que celle-ci était corrélée à la présence de Frankia tout au long du processus symbiotique, soulignant ainsi le rôle clé de CCaMK dans l'infection. Par ailleurs, nous avons cherché à déterminer l'importance du domaine autoinhibiteur de la protéine CCaMK dans l'activation du processus d'organogenèse du nodule. Pour cela, nous avons réalisé et introduit chez C. glauca des constructions géniques de CgCCaMK permettant l'expression de formes tronquées constitutivement actives, car dépourvues du domaine autoinhibiteur/CaM. Nous avons aussi utilisé des formes tronquées du gène MtCCaMK de Medicago truncatula. L'expression de ces formes tronquées de CCaMK a révélé que la levée de l'autoinhibition induit la formation de nodules spontanés indépendamment de l'actinobactérie Frankia. Les résultats obtenus suggèrent que la protéine dérégulée est capable de réactiver la voie de signalisation, ainsi que les gènes situés en aval de CCaMK, qui sont nécessaires à l'organogenèse nodulaire.Mots clés : Casuarina glauca, Frankia, CCaMK, infection, autoinhibition, nodules spontanés / Molecular study of the early stages of actinorhizal symbiosis Casuarina-Frankia: functional analysis of the host plant genes controlling the infectionMore than 80% of plant species are able to develop arbuscular mycorrhizal (AM) symbiosis in association with glomeromycete fungi. In contrast, only some species of the Eurosid I clade, confined to four orders and ten Angiosperm families, are able to form nitrogen-fixing root nodule symbioses with soil bacteria. This concerns plants of the legume family (Fabaceae) and Parasponia associated with Rhizobium bacteria and actinorhizal plants associated with the actinomycete Frankia. Similarly to Legumes, the actinorhizal symbiosis results in the formation of nitrogen-fixing root nodules. However, unlike legume nodule, the actinorhizal nodule has a same origin and structure than a lateral root. Thus, the study of actinorhizal nodules is of particular interest not only for investigating its specific properties but also, for determining common characteristics shared with legume nodules.We have studied the role of CgCCaMK gene during the symbiotic process and nodule organogenesis in the actinorhizal tree Casuarina glauca. CCaMK encodes a calcium and calmodulin dependent protein kinase. In the signalisation cascade leading to both nodulation and mycorrhization in legumes, this gene is acting downstream the calcium oscillations (« calcium spiking ») that occur during the early steps of the symbiotic interaction. It has been suggested that these calcium oscillations are decoded and transduced by the CCaMK protein.We have monitored the spatio-temporal expression of a PromCgCCaMK::GUS fusion during actinorhizal nodulation and have shown that reporter gene expression was correlated with the presence of Frankia along the symbiotic process. This data highlights the role of CgCCaMK during Frankia infection. In addition, we have investigated the role of the CCaMK autoinhibitory/CaM domain in actinorhizal nodule organogenesis. To achieve this goal, we have obtained truncated versions of CgCCaMK lacking the autoinhibitory/CaM domain, and then expressed them into C. glauca. We have also used truncated forms of MtCCaMK from Medicago truncatula. The expression of these CCaMK constructs from C. glauca and M. truncatula was found to induce spontaneous nodulation in the absence of Frankia bacteria. These results suggest that deregulation of the calcium and calmodulin dependent protein kinase is able to reactivate the symbiotic signalling pathway and genes acting downstream CCaMK that are needed for nodule organogenesis.Key words: Casuarina glauca, Frankia, CCaMK, infection, autoinhibition, spontaneous nodules
116

Zvukové vlastnosti jednoslabičných slov v semispontánním dialogu a hlasitém čtení / Acoustic properties of monosyllabic words in semi-spontaneous dialogues and read speech

Ondrušková, Lucie January 2011 (has links)
This thesis investigates temporal characteristics of monosyllabic words (je, se, že) in semi-spontaneous dialogues and read speech. Our material consisted of two sets of recordings from six speakers (three men and three women). The speakers read a text first, and this reading was followed by a recording of a spontaneous dialogue. We investigated differences of temporal characteristics of monosyllabic words between the two types of speech. In addition, we also examined how these characteristics are affected by different variables, which included: position in a stress group, presence of stress, presence of pause and speaker's personality. It was found that the type of speech had a significant influence on duration ratio of sounds in examined words je, že. Word se remained unaffected by the type of speech and generally appeared as a very stable element. The type of speech also influenced variability in duration - this variability proved to be higher in spontaneous speech. The type of speech did not affect average duration of words je, se, že. Position in the stress group also proved to have a significant effect on duration of words. This effect was mainly caused by words which created isolated stress groups - words in such position had longer duration than words in other positions. For words je, se...
117

Faktory ovlivňující šíření dubu letního na výsypce po těžbě uhlí / Factors affecting oak spreading on post mining heaps

Janoušová, Ivana January 2013 (has links)
The study was conducted on spoil heap Podkrušnohorská (50 ř 14'09 S, 12 ř 39'05 V) near Sokolov. Several factors that influence the establishment of oak were studied: the distance from the source of diaspors, type of habitat (succession vs alder reclamation), position of seedling on the wave and impact of animal grazing. Four alder restoration areas and three spontaneous succession areas have been mapped with GPS equipment, the occurence of mature oaks, which could serve as a source of acornsg was also mapped on the dump and in surroundings. Most seedlings (657) were found in the succession and only 98 in alder reclamation, and the occurence in succession was statistically significantly more frequent. The number of seedlings from sources diaspors decreased, the longest distance was over 1300 meters. For three habitats (spontaneous succession, alder reclamation, open space with grass vegetation (Calamagrostis epigeios)) were planted 12 oak seedlings in fence and 12 seedlings outsider of the fence. Annual growth rate and survival of oak were evaluated using two-way ANOVA. Results showed that the area has a significant effect on the growth of oaks. In alder reclamation and the open area had a high mortality of seedlings and small increase, the fence does not have significant influence on these areas....
118

Curling dynamics of naturally curved surfaces : axisymmetric bio-membranes and elastic ribbons / Dynamique d'enroulement de surfaces naturellement courbées : bio-membranes axisymétriques et rubans élastiques

Albarrán Arriagada, Octavio Eduardo 20 December 2013 (has links)
La déformation de matériaux élastique dont l'une au moins des dimensions est petite apparaît dans un grand nombre de structures naturelles ou artificielles pour lesquelles une courbure spontanée est présente. Dans ces travaux de thèse, nous couplons plusieurs approches théoriques à des expériences macroscopiques sur des rubans élastiques afin de comprendre la dynamique d'enroulement de biomembranes ouvertes d'un trou. La motivation est issue d'observations récentes d'enroulements obtenues au cours de la sortie de parasites de la Malaria de globules rouges infectés, et de l'explosion de vésicules polymère. Dans une première partie, nous étudions théoriquement la stabilité d'un pore et la propagation de l'enroulement sur une biomembrane sphérique ouverte. Nous modélisons de façon géométrique l'enroulement toroïdal de la membrane par une spirale d'Archimède de révolution et décentrée. Avec cette hypothèse, nous montrons que la stabilité du pore vis-à-vis de l'enroulement dépend fortement de la tension de ligne et du cisaillement et nous discutons ces résultats dans le cadre de l'enroulement de membranes MIRBCs. De plus, en prenant en compte les différentes sources de dissipation, nous obtenons un très bon accord entre les données expérimentales obtenues pour les MIRBCs et la dynamique d'enroulement obtenue par le calcul. Notre approche montre en particulier que la dissipation dans la membrane due à la redistribution de la matière durant l'enroulement domine sur la dissipation visqueuse dans le milieu.Cependant, la complexité de la géométrie sphérique, ainsi que le nombre limité d'observations microscopiques à l'échelle de la membrane sont une entrave au développement de modèles plus détaillés qui permettraient de décrire complètement le couplage entre écoulement et déformation. Nous avons donc étudié dans une seconde partie la déformation d'enroulement dans le cas de rubans élastiques ayant une courbure spontanée dans différents milieux visqueux et pour différentes conditions élastiques. A grands nombres de Reynolds, en raison de la localisation de la courbure pour les rubans au cours de la propagation du front d'enroulement le long du matériau, nous montrons que l'enroulement atteint rapidement une vitesse de propagation constante. Dans ce régime, le ruban s'enroule sur lui-même de façon compacte, sur un cylindre dont la taille est prévue à partir de la solution de l'onde stationnaire pour l'Elastica. A faible nombre de Reynolds, cependant, se rapprochant des conditions d'enroulement d'une membrane microscopique, nous mettons en évidence l'influence des forces de lubrification sur la nature non-compacte de l'enroulement. La taille globale de la spirale de ruban augmente dans le temps conduisant à une diminution de la puissance élastique libérée et donc à une diminution de la vitesse. Nous discutons dans quelle mesure ces résultats peuvent faire avancer la modélisation de l'enroulement dans les MIRBCs et les vésicules polymère. / Curling deformation of thin elastic surfaces appears in numerous natural and man-made structures where a spontaneous curvature is present. In this thesis, we couple theoretical approaches and macroscopic experiments on elastic ribbons to understand the dynamics of curling of opened bio-membranes, motivated by the need to better understand recent microscopic observations during egress of Malaria infected red blood cells (MIRBC) and bursting of artificial polymersomes.In a first part, we study theoretically pore stability and curling propagation of an initially opened spherical bio-membrane. We model geometrically curling deformation as the revolution of a decentered Archimedean spiral, leading to a prescribed toroidal wrapping of the membrane. In this configuration, we show how the stability of a pore to curling depends strongly on both line-tension and shear elasticity and we discuss these results in relation to the curling of MIRBCs membranes. Moreover, taking into account viscous dissipations, the consequent dynamics we calculate agrees quantitatively well with experimental data obtained during opening of MIRBCs. Our approach shows in particular how the membrane dissipation resulting from the surface redistribution dominates curling dynamics over outer viscous dissipation.However, the complexity of the spherical geometry and the lack of detailed images in microscopic observations hamper the development of more accurate models where the coupling between flow and deformation is fully understood. Subsequently, we study in a second part the curling deformation of macroscopic naturally curved elastic ribbons in different viscous media and elastic conditions. At high Reynolds numbers, due to the tendency of ribbons to localize bending deformations when a curling front travels down the material, we show that curling reaches rapidly a constant propagating velocity. In this regime, the ribbon wraps itself into a compact roll whose size is predicted through the solitary wave solution of the associated Elastica. At low Reynolds numbers, however, closer to the hydrodynamic conditions of curling in microscopic membranes, we show that the strong lubrication forces induce a non-compact curling. The overall size of the spiraling ribbon increases in time leading to a temporal decrease of the released elastic power and therefore a consequent decrease in velocity. We discuss how such discovery sheds a new light on the modeling of curling in MIRBCs and polymersomes.
119

Loughborough University Spontaneous Expression Database and baseline results for automatic emotion recognition

Aina, Segun January 2015 (has links)
The study of facial expressions in humans dates back to the 19th century and the study of the emotions that these facial expressions portray dates back even further. It is a natural part of non-verbal communication for humans to pass across messages using facial expressions either consciously or subconsciously, it is also routine for other humans to recognize these facial expressions and understand or deduce the underlying emotions which they represent. Over two decades ago and following technological advances, particularly in the area of image processing, research began into the use of machines for the recognition of facial expressions from images with the aim of inferring the corresponding emotion. Given a previously unknown test sample, the supervised learning problem is to accurately determine the facial expression class to which the test sample belongs using the knowledge of the known class memberships of each image from a set of training images. The solution to this problem building an effective classifier to recognize the facial expression is hinged on the availability of representative training data. To date, much of the research in the area of Facial Expression Recognition (FER) is still based on posed (acted) facial expression databases, which are often exaggerated and therefore not representative of real life affective displays, as such there is a need for more publically accessible spontaneous databases that are well labelled. This thesis therefore reports on the development of the newly collected Loughborough University Spontaneous Expression Database (LUSED); designed to bolster the development of new recognition systems and to provide a benchmark for researchers to compare results with more natural expression classes than most existing databases. To collect the database, an experiment was set up where volunteers were discretely videotaped while they watched a selection of emotion inducing video clips. The utility of the new LUSED dataset is validated using both traditional and more recent pattern recognition techniques; (1) baseline results are presented using the combination of Principal Component Analysis (PCA), Fisher Linear Discriminant Analysis (FLDA) and their kernel variants Kernel Principal Component Analysis (KPCA), Kernel Fisher Discriminant Analysis (KFDA) with a Nearest Neighbour-based classifier. These results are compared to the performance of an existing natural expression database Natural Visible and Infrared Expression (NVIE) database. A scheme for the recognition of encrypted facial expression images is also presented. (2) Benchmark results are presented by combining PCA, FLDA, KPCA and KFDA with a Sparse Representation-based Classifier (SRC). A maximum accuracy of 68% was obtained recognizing five expression classes, which is comparatively better than the known maximum for a natural database; around 70% (from recognizing only three classes) obtained from NVIE.
120

//Fluxspace: temporary acts as social catalysts in Kansas City / Flux space

Wagner, Benjamin N. January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture and Regional & Community Planning / Jessica Canfield / Kansas City is in the midst of an urban renaissance, with a construction boom within the downtown core in excess of $4.5 billion over the past several years (CVA 2012). In 2010, Kansas City’s Greater Downtown Area Plan (GDAP) was implemented to guide the future transformation and development of the city. Despite its long-term vision and specific goals, including activating the public realm and fostering a strong urban community (City Planning et al. 2010), the GDAP fails to address opportunities for short-term strategies for interim ‘place-making.’ Yet, temporary gatherings are critical to fostering and sustaining a sense of ‘place.’ Kansas City currently has an emerging, vibrant urban culture, but it lacks amenities and spaces to support and celebrate spontaneous social activity. To address this issue, this project proposes a series of prototypical fluxspaces – small, temporary interventions activated by the presence of food trucks - throughout Kansas City’s downtown area. These new temporary acts exploit the potential of underutilized urban surfaces in the short term while re-invigorating social activity and celebrating an emerging urban culture in the long term. Sites are linked to existing mobile food vending hot spots and interventions are timed in conjunction with major Kansas City events and festivals; this grounds the proposed system in Kansas City’s population of temporary users. A detailed schedule ensures that Kansas City’s fluxspaces feature a dynamic, rotating population of food trucks, while fluctuating amenities promote diverse, exciting, and attractive temporary places. Kansas City’s new fluxspaces accommodate spontaneous social gatherings and celebrate their vital importance in fostering a vibrant urban environment. //fluxspace activates Kansas City’s latent urban surfaces, filling the gap between Kansas City’s immediate need for places of temporary gathering and the long-term goals inherent in the vision for Kansas City’s future.

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