Dissertations / Theses on the topic 'Vision 3000'

The structural organisation of species-rich plant-pollinator networks is important to understanding their ecology and evolution and is essential for making informed conservation and restoration decisions. This thesis reports on a study located at different altitudes in nine tributary valleys of the Sacred Valley, Vilcanota Highlands, Peru. The assemblages of flower visitors were described and the plant-flower visitor matrices were analysed and compared to those found from other montane systems. Additionally, the thesis also addressed how the European honeybee (Apis mellifera) fits into these communities. Previous studies have predicted that abundance, diversity, and importance of hymenopterans as pollinators decrease with increasing altitude, where they are replaced by Lepidoptera and Diptera. Contrary to other temperate montane areas, Hymenoptera were more diverse at higher elevations. Diptera was the most abundant functional group overall but did not significantly increase in abundance with altitude as predicted. Species richness of visited plants reached a maximum at the highest altitudes. Using ordination analysis, hummingbirds, honeybees, flies and beetles were identified as major functional groups of flower visitors with significantly different visitation profiles. Nestedness analysis revealed that the plant-flower visitor networks had a similar structure to other published networks, consisting of core groups of generalist plants and animals which interacted with one another and with specialised flower visitors and plants, respectively. The core species varied in identity between valleys, but were usually the species in greatest abundance, implying that the networks were abundance structured. In addition, 85% of the interactions were observed only in single valleys. This context specificity may have implications for the conservation of plant-pollinator interactions in the Sacred Valley. Comparisons of the pollinator efficiencies of honeybees, hummingbirds, native bees and moths to Duranta mandonii (Verbenaceae) demonstrated significant variation among flower visitors in rates of visitation, pollen removal ability and contribution to fruit set. This variation was not correlated: hummingbirds were by far the most frequent visitors but removed virtually no pollen and did not contribute to fruit set. Despite the taxonomic diversity of flower visitors, the main pollinators were large native bumblebees and honeybees. Results highlighted the importance of measuring efficiency components when documenting plant-pollinator interactions, and also demonstrated that visitation rates may give little insight into the relative importance of flower visitors. Overall, the study showed that Apis was the most generalist flower visitor and a dominant core species within networks. However, although Apis visited a relatively large proportion of the flora compared to native taxa, they only intensively utilised a small proportion of available plant species. No evidence was found from the surveys to suggest that honeybees used interference competition and displaced other species. It was suggested that because specialised rare species are frequently dependent on a core of generalist taxa honeybees may play an important role for the possibilities of rare species to persist. However, perhaps the greatest threat to biodiversity and the persistence of plant-flower visitor communities in the Sacred Valley is from the destruction and fragmentation of habitats and from facilitative interactions between native and alien plants, mediated through visitation from honeybees

Thesis (Ph. D.) -- University of Maryland, College Park, 2005.
Thesis research directed by: Computer Science. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

Context: Effective vision processing is an important study area for mobile robots which use vision to detect objects. The problem of detecting small sized coloured objects (e.g. Lego bricks) with no texture information can be solved using either colour or contours of the objects. The shape of such objects doesn‟t help much in detecting the objects due to the poor quality of the picture and small size of the object in the image. In such cases it is seen that the use of hybrid techniques can benefit the overall detection of objects, especially, combining keypoint based methods with the colour based techniques. Robotic motion also plays a vital role in the completion of autonomous tasks. Mobile robots have different configurations for locomotion. The most important system is differential steering because of its application in sensitive areas like military tanks and security robot platforms. The kinematic design of a robotic platform is usually based on the number of wheels and their movement. There can be several configurations of wheels designs, for example differential drives, car-like designs, omni-directional, and synchro drives. Differential drive systems use speed on individual channels to determine the combined speed and trajectory of the robot. Accurate movement of the robot is very important for correct completion of its activities. Objectives: A vision solution is developed that is capable of detecting small sized colour objects in the environment. This has also been compared with other shape detection techniques for performance evaluation. The effect of distance on detection is also investigated for the participating techniques. The precise motion of a four-wheel differential drive system is investigated. The target robot platform uses a differential drive steering system and the main focus of this study is accurate position and orientation control based upon sensor data. Methods: For object detection, a novel hybrid method „HistSURF‟ is proposed and is compared with other vision processing techniques. This method combines the results of colour histogram comparison and detection by the SURF algorithm. A solution for differential steering using a Gyro for the rotational speed measurement is compared with a solution using a speed model and control outputs without feedback (i.e. dead reckoning). Results: The results from the vision experiment rank the new proposed method highest among the other participating techniques. The distance experiment indicates that there is a direct and inverse relation between the distance and detected SURF features. It is also indicated by the results that distance affects the detection rate of the new proposed technique. In case of robot control, the differential drive solution using a speed model has less error rate than the one that uses a Gyro for angle measurement. It is also clear from the results that the greater the difference of speeds among the channels the less smooth is the angular movement. Conclusions: The results indicate that by combining a key-point based technique with colour segmentation, the false positive rate can be reduced and hence object recognition performance improves . It has also become clear that the improved accuracy of the proposed technique is limited to small distances and its performance decreases rapidly with increase in the distance to target objects. For robot control, the results indicate that a Gyro alone cannot improve the movement accuracy of the robotic system due to a variable drift exhibited by the Gyro while in rotation. However, a Gyro can be effective if used in combination with a magnetometer and some form of estimation mechanism like a Kalman filter. A Kalman filter can be used to correct the error in the Gyro by using the output from the magnetometer, resulting in a good estimate.
Bakgrund: Effektiv vision behandling är ett viktigt studieområde för mobila robotar som använder vision att upptäcka föremål. Problemet upptäcka små och medelstora färgade föremål (t.ex. Lego tegelstenar) utan konsistens information kan lösas med färg eller konturer av föremålen. Formen på sådana föremål spelar ingen hjälpa mycket att upptäcka föremål på grund av den dåliga kvaliteten på bild och ringa storlek på objektet i bilden. I sådana fall är det sett att användningen av hybrid-teknik kan gynna den totala upptäckt av föremål, särskilt genom att kombinera keypoint metoder med färgen tekniker. Robotic motion spelar också en viktig roll i genomförandet av självständiga uppgifter. Mobila robotar har olika konfigurationer för transport. Det viktigaste är differentierad styrning på grund av dess tillämpning i känsliga områden som stridsvagnar och säkerhet plattformar robot. Den kinematiska utformningen av en robot plattform är vanligtvis baserad på antalet hjul och deras rörelser. Det kan finnas flera konfigurationer av hjul mönster, till exempel olika enheter, bil-liknande mönster, rundstrålande, och driver synkroniserad. Differential drivsystem använder fart om olika kanaler för att bestämma den kombinerade snabbhet och banan för roboten. Exakt förflyttning av roboten är mycket viktigt för korrekt ifyllande av sin verksamhet. Mål: En vision lösning har utvecklats som kan upptäcka små och medelstora färg objekt i miljön. Detta har också jämfört med andra tekniker form upptäcka för utvärdering av prestanda. Effekten av avstånd vid upptäckt är också undersökas för de deltagande tekniker. Den exakta rörelse av en fyrhjulsdriven olika drivsystem undersöks. Målet robot plattform använder en differentierad system driva styrning och i centrum för denna studie är korrekt läge och riktning kontroll baserat på sensordata. Metoder: För att upptäcka, en ny hybrid metod "HistSURF" föreslås och jämförs med andra tekniker vision bearbetning. Denna metod kombinerar resultaten av färg histogram jämförelse och upptäckt av SURF algoritm. En lösning för differentierad styrning med hjälp av en Gyro för varvtal mätningen jämförs med en lösning med en hastighet modell och utgångar kontroll utan återkoppling (dvs död räkning). Resultat: Resultaten från den vision experiment inom den nya föreslagna metoden högsta bland de andra deltagande tekniker. Avståndet experiment indikerar att det finns ett direkt och omvänd korrelation mellan avstånd och upptäckt SURF funktioner. Det är också framgå av resultatet från det avståndet påverkar upptäckten hastighet av den nya föreslagna tekniken. Vid robot kontroll har skillnaden köra lösningen med en hastighet modell mindre felfrekvens än den som använder en Gyro för vinkelmätning. Det framgår även av resultaten att ju större skillnaden i hastigheter mellan de kanaler de mindre smidiga är vinkelrörelse. Slutsatser: Resultaten visar att genom att kombinera en central-punkt baserad teknik med färg segmentering, den falska positiva kan sänkas och därmed objektigenkänning prestanda ökar. Det har också blivit uppenbart att förbättrad noggrannhet av den föreslagna tekniken är begränsad till små avstånd och dess prestanda minskar snabbt med ökat avstånd till målet objekt. För robot kontroll, tyder resultaten på att en Gyro inte ensam kan förbättra rörligheten noggrannhet robotsystem på grund av en variabel glida ut av Gyro medan rotation. Men en Gyro kan vara effektiva om de används i kombination med en magnetometer och någon form av uppskattning mekanism som ett Kalman filter. En Kalman filter kan användas för att rätta till felet i Gyro med hjälp av utdata från magnetometer, vilket resulterar i en god uppskattning.

Tato diplomová práce si klade za hlavní cíl zhodnotit na základě analýzy úspěšnost propojení marketingových a prodejních aktivit při relaunchi produktu Visine červené oči. Dále také analyzuje stěžejní elementy relaunche Visinu a vyslovuje doporučení pro zajištění úspěšného průběhu prodejních kampaní v oblasti volně prodejných léků.

El sector turismo ha ido incrementando al pasar los años y del mismo modo las necesidades del turista, es por ello que se está logrando mejorar la imagen del país para que así podamos desarrollar una percepción positiva en él. Pero actualmente, a pesar de ello, en Lambayeque han incrementado considerablemente las cifras en cuanto a denuncias de actos delictivos y Túcume no es ajeno a este problema, estos sucesos son factores claves en cuanto se refiere a la seguridad turística, puesto que, influye mucho en la decisión del turista que decide visitar el Complejo Arqueológico de Túcume; por ende esta investigación tiene como objetivo analizar la percepción de seguridad de los turistas nacionales que visitan el Complejo Arqueológico de Túcume y para lograr el desarrollo nos hemos basado en autores netamente del sector turismo. Asimismo, podemos deducir que la investigación tiene un enfoque mixto, debido a la utilización de encuestas para los turistas nacionales y una entrevista dirigida a la directora del Complejo Arqueológico de Túcume. Gracias a ello se determinó que el Turista se encuentra seguro al visitar el Complejo en cuanto se refiere a presencia policial, pero cuenta con déficit en las otras dimensiones de seguridad turística

Visuell-räumliche Aufmerksamkeit spielt eine Schlüsselrolle in der Wortverarbeitung und der Augenbewegungskontrolle beim Lesen. Dennoch bleibt die räumliche und zeitliche Dynamik von Aufmerksamkeitsbereitstellung innerhalb einer Fixation ungeklärt. Die vorliegende Dissertation nutzt drei Ansätze in der Ko-Registrierung von Augenbewegungen und EEG um diese Forschungslücke zu untersuchen und direkte Einblicke in die Aufmerksamkeitsverteilung zwischen Fovea und Parafovea, ihre Anpassung an Verarbeitungsansprüche und Sakkaden sowie ihre Auswirkungen auf Wortverarbeitung zu liefern. In Studie 1 wurde das Probe Paradigma als Maß zur Abbildung räumlicher Aufmerksamkeit ohne Augenbewegungen implementiert. Die vergrößerte, Probe-bezogene N1 zwischen Wortpräsentationen deutet auf eine Bereitstellung und Umverteilung zusätzlicher Ressourcen zur simultanen fovealen und parafovealen Wortverarbeitung hin. Studie 2 untersuchte den Preview Benefit und seine Modulation durch Sakkaden und Verarbeitungsschwierigkeit und zielte darauf ab, das elektrophysiologische Korrelat als indirektes Maß für parafoveale Aufmerksamkeit in ERPs und FRPs zu etablieren. Es zeigte sich ein Effekt des orthographischen Previews auf die N1. Interaktionen mit Lesemodus und Verarbeitungsschwierigkeit implizieren, dass dem Preview Effekt Aufmerksamkeitseffekte zugrunde liegen. In Studie 3 wurden zwei Datensätze hinsichtlich der Lateralisierung von Oszillationen im Alpha-Band untersucht um die in Studie 2 generierten Hypothesen zu unterstützen. Alpha war im sakkadischen Lesen stärker rechts-lateralisiert als in RSVP und eine stärkere Lateralisierung sagte eine kürzere Fixationsdauer vorher, was die Rolle von parafovealer Aufmerksamkeit und ihre Verbindung zu Sakkaden betont. Trotz der Einschränkungen der drei Ansätze stellt die Kombination von Augenbewegungen, ERPs, FRPs und EEG-Oszillationen geeignete Maße für Aufmerksamkeitsprozesse in der Wortverarbeitung dar, die traditionelle Forschungsmethoden ergänzen.
Visuo-spatial attention is a key contributor to word processing and oculomotor control in reading. Yet, the spatial and temporal dynamics of attention allocation within a fixation remain unclear. The present dissertation uses three approaches in the co-registration of eye movements and EEG to investigate this gap and provide direct, online insights into attention distribution across fovea and parafovea, its adaptation to processing load and saccadic behavior, as well as its effects on word processing. In Study 1, the probe paradigm was implemented as a mapping tool of spatial attention adaptation in the absence of eye movements, yielding ERPs. The enhanced probe-related N1 in-between trials indicates a recruitment and redistribution of additional resources to achieve simultaneous foveal and parafoveal word-recognition. Study 2 tested the preview benefit and its modulation by saccades and foveal load, thereby aiming at establishing its electrophysiological correlate as an indirect index of parafoveal attention allocation in ERPs and FRPs. There was an effect of orthographic preview on the N1. Interactions with reading mode and foveal load indicate underlying attention effects. In Study 3, two datasets were reanalyzed with regard to the lateralization of oscillatory activity in the alpha-band in order to directly support the assumptions generated in Study 2. Alpha was more strongly right-lateralized in saccadic reading compared to RSVP, and moment-to-moment lateralization predicted shorter subsequent fixation duration, emphasizing the role of parafoveal attention allocation and its relation to saccades. Despite the limitations of the three approaches at this point, the combination of eye movements, ERPs, FRPs, and EEG oscillations provides suitable online markers of attention processes in word recognition that complement traditional research methods.

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HP - Hewlett-Packard Brasil Ltda
Milton Valente
Segmentação de objetos em imagens e vídeos é uma área relativamente antiga na área de processamento de imagens e visão computacional. De fato, recentemente, devido à grande evolução dos sistemas computacionais em termos de hardware e à popularização da internet, uma aplicação de segmentação de imagens de pessoas que vem ganhando grande destaque na área acadêmica e comercial são as videoconferências. Esse tipo de aplicação traz benefícios a diferentes áreas, como telemedicina, educação à distância, e principalmente empresarial. Diversas empresas utilizam esse tipo de recurso para realizar reuniões/conferências a nível global economizando quantias consideráveis de recursos. No entanto, videoconferências ainda não proporcionam a mesma experiência que as pessoas têm quando estão num mesmo ambiente. Portanto, esse trabalho propõe o desenvolvimento de um sistema de segmentação da imagem do locutor, específico para videoconferências, a fim de permitir futuros processamentos que aumentem a sensação de imersão dos participantes, como por exemplo, a substituição do fundo da imagem por um fundo padrão em todos ambientes. O sistema proposto utiliza basicamente um algoritmo de programação dinâmica guiado por energias extraídas da imagem, envolvendo informações de borda, movimento e probabilidade. Através de diversos testes realizados, observou-se que o sistema apresenta resultados equiparáveis aos do estado da arte do tema, sendo capaz de ser executado em tempo real a uma taxa de 8 FPS, mesmo com um código não otimizado. O grande diferencial do sistema proposto é que nenhum tipo de treinamento prévio é necessário para efetuar a segmentação
Object segmentation has been discussed on Computer Vision and Image processing fields for quite some time. Recently, given the hardware evolution and popularization of the World Wide Web, videoconferences have been the main discussion in this area. This technique brings advantages to many fields, such as telemedicine, education (distance learning), and mainly to the business world. Many companies use videoconferences for worldwide meetings, in order to save a substantial amount o f resources. However, videoconferences still do not provide the same experience a s people have when they are in the same room. Therefore, in this paper we propose the development of a system to segment the image of a person who is attending the videoconference, in order to allow future processing that may increase the experience of being in the same room. For instance, the background of the scene could be replaced by a standard one for all participants. The proposed system uses a dynamic programming algorithm guided by energies, such as image edges, motion and probabilistic information. After extensive tests, we could conclude that the results obtained are comparable to other state of the art works and the system is able to execute in real time at 8 FPS. The advantage of the proposed system when compared to others is that no previous training is required in order to perform the segmentation

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Universidade Federal de Minas Gerais
It is estimated that in Brazil one of 500 children have low vision. In this population, among all difficult possible, have the dependency in daily life activities (ADL), that influence at social integration, learning and school inclusion. Detached for the regular teacher s work inside the class with ADL´s children especially in preschool. The propose of this work was to develop, implement and evaluate one individual program of collaborative assessoring in Occupational Therapist for teacher training, to increase their repertoire of strategies and resources to promote the independence of preschool children with low vision in activities of daily hygiene and nutrition, called PRÓ-AVD . Study participants were 10 teachers and 10 students with low vision aged between 4 and 6 years of regular education children. The experimental design of the study consisting of 5 teachers and 5 students belonging to the Experimental Group who received the intervention in a first moment, and 5 teachers and 5 students to the control group that received no intervention. The elaborate of the training program involved the study of children's abilities in the tasks of self, and his visual capacity, the original repertoire of the teacher, and the dynamics of dyad Teacher - Student in carrying out AVDs. The implementation happened through collaborative assessoring, on 6 weekly meetings, consecutive, consisting of interactive dynamic between the researcher and teacher. Measures were taken pre-test and post-test and a field diary, analysis of film and questionnaires to assess qualitatively and quantitatively the effect of the intervention program in increasing the repertoire of teachers to promote the independence of their students in AVDs. The program showed efficient when applied, the results were increasing her preparation and teacher repertory to work with hygienic and alimentation activities of the student with low vision. It is believed that the use of methods and teaching approaches, practice activities, feedback and support of researcher presence than weekly meetings were crucial to the membership and participation of teachers, as well as to obtain the results.
Estima-se que no Brasil uma entre 500 crianças possua baixa visão. Dentre as possíveis dificuldades apresentadas por esta população, encontra-se a dependência nas Atividades de Vida Diária (AVD), o que influencia em sua interação social, aprendizagem e inclusão escolar. Nesta perspectiva, o trabalho do professor regular dentro de sala de aula com estas AVDs nos alunos com baixa visão é de grande importância especialmente na pré-escola. O objetivo deste estudo foi elaborar, implementar e avaliar um programa individualizado de consultoria colaborativa em Terapia Ocupacional, com o intuito de capacitação de professores, no sentido de aumentar seu repertório de estratégias e recursos para promover a independência de crianças pré-escolares com baixa visão nas atividades de vida diária de higiene e alimentação, denominado PRÓ-AVD. Participaram do estudo 10 professores e 10 alunos com baixa visão com idades entre 4 e 6 anos, do ensino infantil regular. O delineamento do estudo foi experimental constando de 5 Professores e 5 Alunos pertencentes ao Grupo Experimental, que receberam a intervenção em um primeiro momento, e 5 Professores e 5 Alunos ao Grupo Controle, que não receberam a intervenção. A elaboração do programa de capacitação envolveu o estudo das habilidades da criança nas tarefas de autocuidado, e de sua capacidade visual, do repertório inicial do Professor, e da dinâmica da díade Professor Aluno durante a realização das AVDs. A implementação ocorreu por meio de consultoria colaborativa em 6 encontros semanais, consecutivos, constituídos de dinâmicas interativas entre a Pesquisadora e a Professora. Foram realizadas medidas pré-teste e pósteste, utilizou-se diário de campo, análise de filmagens e questionários a fim de avaliar quantitativa e qualitativamente o efeito do programa de intervenção no aumento do repertório dos professores para promover a independência de seus alunos nas AVDs. O programa se mostrou eficaz em sua aplicação e os resultados observados apontaram para o aumento do preparo e do repertório dos professores do Grupo Experimental para trabalhar com as atividades de higiene e alimentação de seus alunos com baixa visão. Acredita-se que a utilização de métodos e abordagens didáticas, atividades práticas, feedback e suporte presencial da pesquisadora, além dos encontros semanais, foram decisivos para a adesão e participação das professoras, assim como para a obtenção dos resultados positivos.

This paper examines different foreign policies of the Republic of Korea (South Korea) towards the Democratic People’s Republic of Korea (North Korea) with regards to a peaceful reunification of the Korean Peninsula. The paper uses the theoretical framework of Social Constructivism to analyze what impact the different foreign policies of South Korea towards North Korea have had on their relations, thus providing an understanding of what impact those foreign policies have had on the peaceful reunification process of the Korean Peninsula. The paper will also look at the First Korean Nuclear Crisis, the Second Korean Nuclear Crisis, the ROKS Cheonan sinking and the shelling of Yeonpyeong, and with the help from the theoretical framework of Social Constructivism, analyze what impact those incidents have had on South Korea’s foreign policy and relations with North Korea, thus providing an understanding what impact those incidents have had on the peaceful reunification process of the Korean Peninsula.

Dans la région méditerranéenne, l'agriculture irriguée est confrontée de plus en plus aux problèmes de rareté physique et de pollution de l'eau, à la concurrence plus intense des autres usages, aux fluctuations des marchés agricoles et aux contraintes institutionnelles imposées par les crises économique et environnementale. Cette thèse propose d'analyser les liens entre les formes sociales d'exploitation agricole et les rapports aux risques liés à l'irrigation et d'interpréter ces derniers dans le cadre plus général des rapports des agriculteurs aux mondes sociétal et naturel. À cet effet, nous construisons un modèle d'analyse, à partir des éléments empruntés principalement aux approches théoriques de la vulnérabilité, pour comprendre les caractères complexe et dynamique de la vulnérabilité liée à l'irrigation. Les résultats d’analyse, dans le contexte de la plaine de la Mitidja en Algérie ou dans une perspective comparative entre plusieurs territoires irrigués en Méditerranée occidentale, montrent globalement une différenciation importante des formes sociales d'exploitation agricole, fondée sur des inégalités d'accès aux ressources productives et aux opportunités sociales. De plus, sur le plan des rapports aux risques liés à l'irrigation, la majorité des exploitations sont dotées de capacités d'adaptation plutôt élevées au Nord, tandis que les figures vulnérables dominent largement au Sud. Ces différences renvoient généralement aux clivages Nord/Sud dans les rapports aux mondes sociétal et naturel
In the Mediterranean area, irrigated agriculture is faces growing problems of physical scarcity and water pollution, increased competition from other uses, to fluctuations in agricultural markets and institutional constraints imposed by the economic and environmental crises. This thesis aims to analyze the links between social forms of agricultural farm and their report towards risks related to irrigation and to interpret these latter in the broader context of the reports of farmers to societal and to natural worlds. To this end, we construct a model of analysis, from elements borrowed mainly to theoretical approaches to vulnerability, to understand the complex and dynamic character of vulnerability associated to irrigation. The analysis results in the context of the plain of Mitidja in Algeria or in a comparative perspective between several irrigated areas in the western Mediterranean shows a significant differentiation of social forms of farming, based on unequal access to productive resources and social opportunities. Furthermore, in terms of relations to the risks associated to irrigation, the majority of farms are equipped with coping capacities rather high in the North, while vulnerable configurations dominate the South. These differences generally refer to the North / South division in relations to societal and natural worlds

We humans are visual creatures, constantly extracting information from the world around us. The source of our ability to understand the visual world is an intricate arrangement of multiple areas in our brains: the visual system. It enables us to recognize our friends and family in diverse conditions, to focus our attention on important aspects of a scene and performs invariant object categorization on multiple levels of abstraction. Vision has been in the focus of scientific interest for many decades and yet our knowledge of the cortical mechanisms involved is only limited. I here describe a series of experiments, in which we investigated how the visual system robustly and efficiently extracts meaning from the environment. In particular, I will focus on thee aspects of object recognition: sampling the environment, visual invariance, and categorization and plasticity. Starting with the selection of visual information, three eyetracking experiments are described in which we investigate the interplay of overt visual attention and object recognition. We show that overt visual attention and object recognition exert a bi-directional influence on each other. Whereas initial patterns of overt visual attention causally affect the outcome of the later recognition, briefly presented contextual information leads to substantial changes in the attentional sampling behavior, which can be best understood in terms of a shifting exploration-exploitation bias. Following this, we turn to visual processing within the system and ask how invariant object recognition is accomplished despite large variation in retinal input. As an exemplary case, we focus on changes introduced by rotations in depth. Using a variety of techniques, ranging from fMRI to TMS and EEG, we show that viewpoint symmetry, i.e. the selectivity to mirror-symmetric viewing angles, is a prevalent feature of visual processing across a wide range of higher-level visual regions. These findings jointly suggest that viewpoint-symmetry constitutes a key computational step in achieving full viewpoint invariance. On the next level of abstraction, we investigate how visual categories are represented at different levels of experience, from novice to expert. By combining training of novel visual categories with psychophysical measures, we demonstrate a change in the underlying type of category representation. Following this, we combine the training paradigm with electrophysiological measurements. In line with our behavioral results, these data reveal a spatiotemporal shift in category selectivity: from late and frontal to early occipitotemporal activity. These results suggest that novel and re-occurring categories rely on partially separate cortical networks, allowing the brain to balance robust and fast recognition with considerable flexibility and plasticity. The results of all experiments presented are unified by the concept of a system that has evolved efficient mechanisms for robust performance in a large variety of conditions. Using dynamic sampling strategies, computational shortcuts and a division of labor, the visual system is optimally equipped to support higher-level cognitive function in a complex and constantly changing environment.