225 research outputs found
From Data to Software to Science with the Rubin Observatory LSST
The Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) dataset
will dramatically alter our understanding of the Universe, from the origins of
the Solar System to the nature of dark matter and dark energy. Much of this
research will depend on the existence of robust, tested, and scalable
algorithms, software, and services. Identifying and developing such tools ahead
of time has the potential to significantly accelerate the delivery of early
science from LSST. Developing these collaboratively, and making them broadly
available, can enable more inclusive and equitable collaboration on LSST
science.
To facilitate such opportunities, a community workshop entitled "From Data to
Software to Science with the Rubin Observatory LSST" was organized by the LSST
Interdisciplinary Network for Collaboration and Computing (LINCC) and partners,
and held at the Flatiron Institute in New York, March 28-30th 2022. The
workshop included over 50 in-person attendees invited from over 300
applications. It identified seven key software areas of need: (i) scalable
cross-matching and distributed joining of catalogs, (ii) robust photometric
redshift determination, (iii) software for determination of selection
functions, (iv) frameworks for scalable time-series analyses, (v) services for
image access and reprocessing at scale, (vi) object image access (cutouts) and
analysis at scale, and (vii) scalable job execution systems.
This white paper summarizes the discussions of this workshop. It considers
the motivating science use cases, identified cross-cutting algorithms,
software, and services, their high-level technical specifications, and the
principles of inclusive collaborations needed to develop them. We provide it as
a useful roadmap of needs, as well as to spur action and collaboration between
groups and individuals looking to develop reusable software for early LSST
science.Comment: White paper from "From Data to Software to Science with the Rubin
Observatory LSST" worksho
Giving eyes to ICT!, or How does a computer recognize a cow?
Het door Schouten en andere onderzoekers op het CWI ontwikkelde systeem berust op het beschrijven van beelden met behulp van fractale meetkunde. De menselijke waarneming blijkt mede daardoor zo efficiënt omdat zij sterk werkt met gelijkenissen. Het ligt dus voor de hand het te zoeken in wiskundige methoden die dat ook doen. Schouten heeft daarom beeldcodering met behulp van 'fractals' onderzocht. Fractals zijn zelfgelijkende meetkundige figuren, opgebouwd door herhaalde transformatie (iteratie) van een eenvoudig basispatroon, dat zich daardoor op steeds kleinere schalen vertakt. Op elk niveau van detaillering lijkt een fractal op zichzelf (Droste-effect). Met fractals kan men vrij eenvoudig bedrieglijk echte natuurvoorstellingen maken. Fractale beeldcodering gaat ervan uit dat het omgekeerde ook geldt: een beeld effectief opslaan in de vorm van de basispatronen van een klein aantal fractals, samen met het voorschrift hoe het oorspronkelijke beeld daaruit te reconstrueren. Het op het CWI in samenwerking met onderzoekers uit Leuven ontwikkelde systeem is mede gebaseerd op deze methode.
ISBN 906196502
Robots learn to behave: improving human-robot collaboration in flexible manufacturing applications
L'abstract è presente nell'allegato / the abstract is in the attachmen
Interactive Brain Tumor Segmentation with Inclusion Constraints
This thesis proposes an improved interactive brain tumor segmentation method based on graph cuts, which is an efficient global optimization framework for image segmentation, and star shape, which is a general segmentation shape prior with minimal user assistance. Our improvements lie in volume ballooning, compactness measure and inclusion constraints.
Volume ballooning is incorporated to help to balloon segmentation for situations where the foreground and background have similar appearance models and changing relative weight between appearance model and smoothness term cannot help to achieve an accurate segmentation. We search different ballooning parameters for different slices since an appropriate ballooning force may vary between slices.
As the evaluation for goodness of segmentation in parameter searching, two new compactness measures are introduced, ellipse fitting and convexity deviation. Ellipse fitting is a measure of compactness based on the deviation from an ellipse of best fit, which prefers segmentation with an ellipse shape. And convexity deviation is a more strict measure for preferring convex segmentation. It uses the number of convexity violation pixels as the measure for compactness.
Inclusion constraints is added between slices to avoid side slice segmentation larger than the middle slice problem. The inclusion constraints consist of mask inclusion, which is implemented by an unary term in graph cuts, and pairwise inclusion, which is implemented by a pairwise term. Margin is allowed in inclusion so that the inclusion region is enlarged.
With all these improvements, the final result is promising. The best performance for our dataset is 88% compared to the previous system that achieved 87%
Non-Visual Representation of Complex Documents for Use in Digital Talking Books
Essential written information such as text books, bills, and catalogues needs to be accessible by everyone. However, access is not always available to vision-impaired people. As they require electronic documents to be available in specific formats. In order to address the accessibility issues of electronic documents, this research aims to design an affordable, portable, standalone and simple to use complete reading system that will convert and describe complex components in electronic documents to print disabled users
Configurable Input Devices for 3D Interaction using Optical Tracking
Three-dimensional interaction with virtual objects is one of the aspects that needs to be addressed
in order to increase the usability and usefulness of virtual reality. Human beings
have difficulties understanding 3D spatial relationships and manipulating 3D user interfaces,
which require the control of multiple degrees of freedom simultaneously. Conventional interaction
paradigms known from the desktop computer, such as the use of interaction devices as
the mouse and keyboard, may be insufficient or even inappropriate for 3D spatial interaction
tasks.
The aim of the research in this thesis is to develop the technology required to improve 3D
user interaction. This can be accomplished by allowing interaction devices to be constructed
such that their use is apparent from their structure, and by enabling efficient development of
new input devices for 3D interaction.
The driving vision in this thesis is that for effective and natural direct 3D interaction the
structure of an interaction device should be specifically tuned to the interaction task. Two
aspects play an important role in this vision. First, interaction devices should be structured
such that interaction techniques are as direct and transparent as possible. Interaction techniques
define the mapping between interaction task parameters and the degrees of freedom of
interaction devices. Second, the underlying technology should enable developers to rapidly
construct and evaluate new interaction devices.
The thesis is organized as follows. In Chapter 2, a review of the optical tracking field is
given. The tracking pipeline is discussed, existing methods are reviewed, and improvement
opportunities are identified.
In Chapters 3 and 4 the focus is on the development of optical tracking techniques of rigid
objects. The goal of the tracking method presented in Chapter 3 is to reduce the occlusion
problem. The method exploits projection invariant properties of line pencil markers, and the
fact that line features only need to be partially visible.
In Chapter 4, the aim is to develop a tracking system that supports devices of arbitrary
shapes, and allows for rapid development of new interaction devices. The method is based on
subgraph isomorphism to identify point clouds. To support the development of new devices
in the virtual environment an automatic model estimation method is used.
Chapter 5 provides an analysis of three optical tracking systems based on different principles.
The first system is based on an optimization procedure that matches the 3D device
model points to the 2D data points that are detected in the camera images. The other systems
are the tracking methods as discussed in Chapters 3 and 4.
In Chapter 6 an analysis of various filtering and prediction methods is given. These
techniques can be used to make the tracking system more robust against noise, and to reduce
the latency problem.
Chapter 7 focusses on optical tracking of composite input devices, i.e., input devices
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that consist of multiple rigid parts that can have combinations of rotational and translational
degrees of freedom with respect to each other. Techniques are developed to automatically
generate a 3D model of a segmented input device from motion data, and to use this model to
track the device.
In Chapter 8, the presented techniques are combined to create a configurable input device,
which supports direct and natural co-located interaction. In this chapter, the goal of the thesis
is realized. The device can be configured such that its structure reflects the parameters of the
interaction task.
In Chapter 9, the configurable interaction device is used to study the influence of spatial
device structure with respect to the interaction task at hand. The driving vision of this thesis,
that the spatial structure of an interaction device should match that of the task, is analyzed
and evaluated by performing a user study.
The concepts and techniques developed in this thesis allow researchers to rapidly construct
and apply new interaction devices for 3D interaction in virtual environments. Devices
can be constructed such that their spatial structure reflects the 3D parameters of the interaction
task at hand. The interaction technique then becomes a transparent one-to-one mapping
that directly mediates the functions of the device to the task. The developed configurable interaction
devices can be used to construct intuitive spatial interfaces, and allow researchers to
rapidly evaluate new device configurations and to efficiently perform studies on the relation
between the spatial structure of devices and the interaction task
Automatic 3D Building Detection and Modeling from Airborne LiDAR Point Clouds
Urban reconstruction, with an emphasis on man-made structure modeling, is an active research area with broad impact on several potential applications. Urban reconstruction combines photogrammetry, remote sensing, computer vision, and computer graphics. Even though there is a huge volume of work that has been done, many problems still remain unsolved. Automation is one of the key focus areas in this research. In this work, a fast, completely automated method to create 3D watertight building models from airborne LiDAR (Light Detection and Ranging) point clouds is presented. The developed method analyzes the scene content and produces multi-layer rooftops, with complex rigorous boundaries and vertical walls, that connect rooftops to the ground. The graph cuts algorithm is used to separate vegetative elements from the rest of the scene content, which is based on the local analysis about the properties of the local implicit surface patch. The ground terrain and building rooftop footprints are then extracted, utilizing the developed strategy, a two-step hierarchical Euclidean clustering. The method presented here adopts a divide-and-conquer scheme. Once the building footprints are segmented from the terrain and vegetative areas, the whole scene is divided into individual pendent processing units which represent potential points on the rooftop. For each individual building region, significant features on the rooftop are further detected using a specifically designed region-growing algorithm with surface smoothness constraints. The principal orientation of each building rooftop feature is calculated using a minimum bounding box fitting technique, and is used to guide the refinement of shapes and boundaries of the rooftop parts. Boundaries for all of these features are refined for the purpose of producing strict description. Once the description of the rooftops is achieved, polygonal mesh models are generated by creating surface patches with outlines defined by detected vertices to produce triangulated mesh models. These triangulated mesh models are suitable for many applications, such as 3D mapping, urban planning and augmented reality
Human-aware space sharing and navigation for an interactive robot
Les méthodes de planification de mouvements robotiques se sont développées à un rythme accéléré ces dernières années.
L'accent a principalement été mis sur le fait de rendre les robots plus efficaces, plus sécurisés et plus rapides à réagir à des situations imprévisibles. En conséquence, nous assistons de plus en plus à l'introduction des robots de service dans notre vie quotidienne, en particulier dans les lieux publics tels que les musées, les centres commerciaux et les aéroports. Tandis qu'un robot de service mobile se déplace dans l'environnement humain, il est important de prendre en compte l'effet de son comportement sur les personnes qu'il croise ou avec lesquelles il interagit. Nous ne les voyons pas comme de simples machines, mais comme des agents sociaux et nous nous attendons à ce qu'ils se comportent de manière similaire à l'homme en suivant les normes sociétales comme des règles. Ceci a créé de nouveaux défis et a ouvert de nouvelles directions de recherche pour concevoir des algorithmes de commande de robot, qui fournissent des comportements de robot acceptables, lisibles et proactifs. Cette thèse propose une méthode coopérative basée sur l'optimisation pour la planification de trajectoire et la navigation du robot avec des contraintes sociales intégrées pour assurer des mouvements de robots prudents, conscients de la présence de l'être humain et prévisibles. La trajectoire du robot est ajustée dynamiquement et continuellement pour satisfaire ces contraintes sociales. Pour ce faire, nous traitons la trajectoire du robot comme une bande élastique (une construction mathématique représentant la trajectoire du robot comme une série de positions et une différence de temps entre ces positions) qui peut être déformée (dans l'espace et dans le temps) par le processus d'optimisation pour respecter les contraintes données. De plus, le robot prédit aussi les trajectoires humaines plausibles dans la même zone d'exploitation en traitant les chemins humains aussi comme des bandes élastiques. Ce système nous permet d'optimiser les trajectoires des robots non seulement pour le moment présent, mais aussi pour l'interaction entière qui se produit lorsque les humains et les robots se croisent les uns les autres. Nous avons réalisé un ensemble d'expériences avec des situations interactives humains-robots qui se produisent dans la vie de tous les jours telles que traverser un couloir, passer par une porte et se croiser sur de grands espaces ouverts. La méthode de planification
coopérative proposée se compare favorablement à d'autres schémas de planification de la navigation à la pointe de la
technique. Nous avons augmenté le comportement de navigation du robot avec un mouvement synchronisé et réactif de sa tête. Cela permet au robot de regarder où il va et occasionnellement de détourner son regard vers les personnes voisines pour montrer que le robot va éviter toute collision possible avec eux comme prévu par le planificateur. À tout moment, le robot pondère les multiples critères selon le contexte social et décide de ce vers quoi il devrait porter le regard. Grâce à une étude utilisateur en ligne, nous avons montré que ce mécanisme de regard complète efficacement le comportement de navigation ce qui améliore la lisibilité des actions du robot. Enfin, nous avons intégré notre schéma de navigation avec un système de supervision plus large qui peut générer conjointement des comportements du robot standard tel que l'approche d'une personne et l'adaptation de la vitesse du robot selon le groupe de personnes que le robot guide dans des scénarios
d'aéroport ou de musée.The methods of robotic movement planning have grown at an accelerated pace in recent years. The emphasis has mainly been on making robots more efficient, safer and react faster to unpredictable situations. As a result we are witnessing more and more service robots introduced in our everyday lives, especially in public places such as museums, shopping malls and airports. While a mobile service robot moves in a
human environment, it leaves an innate effect on people about its demeanor. We do not see them as mere machines but as social agents and expect them to behave humanly by following societal norms and rules. This has created new challenges and opened new research avenues for designing robot control algorithms that deliver human-acceptable, legible and proactive robot behaviors. This thesis proposes a optimization-based cooperative method for trajectoryplanning and navigation with in-built social constraints for keeping robot motions safe, human-aware and predictable. The robot trajectory is dynamically and continuously adjusted to satisfy these social constraints. To do so, we treat the robot trajectory as an elastic band (a mathematical construct representing the robot path
as a series of poses and time-difference between those poses) which can be deformed (both in space and time) by the optimization process to respect given constraints. Moreover, we also predict plausible human trajectories in the same operating area by treating human paths also as elastic bands. This scheme allows us to optimize the robot trajectories not only for the current moment but for the entire interaction that happens when humans and robot cross each other's paths. We carried out a set of experiments with canonical human-robot interactive situations that happen in our everyday lives such as crossing a hallway, passing through a door and intersecting paths on wide open spaces. The proposed cooperative planning method compares favorably against other stat-of-the-art human-aware navigation planning schemes. We have augmented robot navigation behavior with synchronized and responsive movements of the robot head, making the robot look where it is going and occasionally diverting its gaze towards nearby people to acknowledge that robot will avoid any possible collision with them. At any given moment the robot weighs multiple criteria according to the social context and decides where it should turn its gaze. Through an online user study we have shown that such gazing mechanism effectively complements the navigation behavior and it improves legibility of the robot actions. Finally, we have integrated our navigation scheme with a broader supervision system which can jointly generate normative robot behaviors such as approaching a person and adapting the robot speed according to a group of people who the robot guides in airports or museums
Виртуальное сообщество: формирование каналов виртуального общения институциональной корпорации в сфере высшего образования
Results of philosophical research devoted to studying of virtual communities are considered in
article. The author gives an example effective cooperation in virtual communities these are virtual
communications in scientifically-educational sphere - higher education web-sites, professional
forums, teleconferences. Studying a phenomenon of virtual communities (phylosophical position) has
allowed to reveal increasing value of this work and open participation of people in modern virtual
communications.Рассмотрены результаты философского исследования, посвященного изучению виртуальных сообществ. Автор приводит примеры эффективного сотрудничества в виртуальных сообществах – это виртуальная коммуникация в научно-образовательной сфере: веб-сайты, профессиональные форумы, телеконференции. Изучение феномена виртуальных сообществ (с философской точки зрения) позволило выявить увеличивающуюся ценность данной работы и открытого участия людей в современном виртуальном общении
Learning and mining from personal digital archives
Given the explosion of new sensing technologies, data storage has become significantly cheaper and consequently, people increasingly rely on wearable devices to create personal digital archives. Lifelogging is the act of recording aspects of life in digital format for a variety of purposes such as aiding human memory, analysing human lifestyle and diet monitoring. In this dissertation we are concerned with Visual Lifelogging, a form of lifelogging based on the passive capture of photographs by a wearable camera. Cameras, such as Microsoft's SenseCam can record up to 4,000 images per day as well as logging data from several incorporated sensors. Considering the volume, complexity and heterogeneous nature of such data collections, it is a signifcant challenge to interpret and extract knowledge for the practical use of lifeloggers and others.
In this dissertation, time series analysis methods have been used to identify and extract useful information from temporal lifelogging images data, without benefit of prior knowledge. We focus, in particular, on three fundamental topics: noise reduction, structure and characterization of the raw data; the detection of multi-scale patterns; and the mining of important, previously unknown repeated patterns in the time series of lifelog image data.
Firstly, we show that Detrended Fluctuation Analysis (DFA) highlights the
feature of very high correlation in lifelogging image collections. Secondly, we show that study of equal-time Cross-Correlation Matrix demonstrates atypical or non-stationary characteristics in these images. Next, noise reduction in the Cross-Correlation Matrix is addressed by Random Matrix Theory (RMT) before Wavelet multiscaling is used to characterize the `most important' or `unusual' events through analysis of the associated dynamics of the eigenspectrum. A motif discovery technique is explored for detection of recurring and recognizable episodes of an individual's image data. Finally, we apply these motif discovery techniques to two known lifelog data collections, All I Have Seen (AIHS) and NTCIR-12 Lifelog, in order to examine multivariate recurrent patterns of multiple-lifelogging users
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