1. |
- Yun, Yixiao, 1987, et al.
(author)
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Maximum-Likelihood Object Tracking from Multi-View Video by Combining Homography and Epipolar Constraints
- 2012
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In: 6th ACM/IEEE Int'l Conf on Distributed Smart Cameras (ICDSC 12), Oct 30 - Nov.2, 2012, Hong Kong. - 9781450317726 ; , s. 6 pages-
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Conference paper (peer-reviewed)abstract
- This paper addresses problem of object tracking in occlusion scenarios, where multiple uncalibrated cameras with overlapping fields of view are used. We propose a novel method where tracking is first done independently for each view and then tracking results are mapped between each pair of views to improve the tracking in individual views, under the assumptions that objects are not occluded in all views and move uprightly on a planar ground which may induce a homography relation between each pair of views. The tracking results are mapped by jointly exploiting the geometric constraints of homography, epipolar and vertical vanishing point. Main contributions of this paper include: (a) formulate a reference model of multi-view object appearance using region covariance for each view; (b) define a likelihood measure based on geodesics on a Riemannian manifold that is consistent with the destination view by mapping both the estimated positions and appearances of tracked object from other views; (c) locate object in each individual view based on maximum likelihood criterion from multi-view estimations of object position. Experiments have been conducted on videos from multiple uncalibrated cameras, where targets experience long-term partial or full occlusions. Comparison with two existing methods and performance evaluations are also made. Test results have shown effectiveness of the proposed method in terms of robustness against tracking drifts caused by occlusions.
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2. |
- Kavathatzopoulos, Iordanis, 1956-
(author)
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Robots and systems as autonomous ethical agents
- 2010
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In: INTECH 2010. - Bangkok : Assumption University. - 9789746151108 ; , s. 5-9
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Conference paper (peer-reviewed)abstract
- IT systems and robots can help us to solve many problems caused by the quantity, variation and complexity of information; because we need to handle dangerous and risky situations; or because of our social and emotional needs like elderly care. In helping us, these systems have to make decisions and act accordingly to achieve the goals for which they were built. Ethical decision support tools can be integrated into robots and other decision making systems to secure that decisions are made according to the basic theories of philosophy and to the findings of psychological research. This can be done, in non-independent systems, as a way for the system to report to its operator, and to support the operator's ethical decision making. On the other hand, fully independent systems should be able to regulate their own decision making strategies and processes. However, this cannot be based on normative predefined criteria, or on the ability to make choices, or on having own control, or on ability of rational processing. It seems that it is necessary for an independent robot or decision system to have "emotions." That is, a kind of ultimate purposes that can lead the decision process, and depending on the circumstances, guide the adoption of a decision strategy, whatever it may be, rational, heuristic or automatic.
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3. |
- Kavathatzopoulos, Iordanis, 1956-, et al.
(author)
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What are ethical agents and how can we make them work properly?
- 2011
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In: The computational turn. - Münster : MV-Wissenschaft. - 9783869913551 ; , s. 151-153
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Conference paper (peer-reviewed)abstract
- To support ethical decision making in autonomous agents, we suggest to implement decision tools based on classical philosophy and psychological research. As one possible avenue, we present EthXpert, which supports the process of structuring and assembling information about situations with possible moral implications.
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4. |
- Patrignani, Norberto
(author)
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From computer ethics to future (and information) ethics : The challenge of Nano-Bots
- 2014
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In: Ethical dimensions of bio-nanotechnology. - Hershey, PA, USA : IGI Global. - 9781466618947
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Book chapter (peer-reviewed)abstract
- One of the emerging technologies that is getting a lot of attention is nano-technology. In particular,in this area, the convergence of research fields of biotechnology, information technology, nanotechnologyand neuroscience (or cognitive science) is introducing nano-robots, or nano-bots. These machines promise to lead to the development of a large number potential applications in medicine,but at the same time they raise also a lot of social and ethical issues. This chapter introduces severalways to start an ethical reflection in relation to nano-bots. The traditional "computer ethics"approach and the new "future ethics" proposition are both discussed and applied to this technology.The challenges introduced by nano-bots are so complex that it is possible that the application of thePrecautionary Principle would be required. A further ethical analysis of nano-bots applications inmedicine may benefit from new methodologies and strategies such as the stakeholders' network andFloridi's "entropy (the evil of Infosphere)" concept.
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5. |
- Gu, Irene Yu-Hua, 1953, et al.
(author)
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Grassmann Manifold Online Learning and Partial Occlusion Handling for Visual Object Tracking under Bayesian Formulation
- 2012
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In: Proceedings - International Conference on Pattern Recognition. - 1051-4651. - 9784990644109 ; , s. 1463-1466
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Conference paper (peer-reviewed)abstract
- This paper addresses issues of online learning and occlusion handling in video object tracking. Although manifold tracking is promising, large pose changes and long term partial occlusions of video objects remain challenging.We propose a novel manifold tracking scheme that tackles such problems, with the following main novelties: (a) Online estimation of object appearances on Grassmann manifolds; (b) Optimal criterion-based occlusion handling during online learning; (c) Nonlinear dynamic model for appearance basis matrix and its velocity; (b) Bayesian formulations separately for the tracking and the online learning process. Two particle filters are employed: one is on the manifold for generating appearance particles and another on the linear space for generating affine box particles. Tracking and online updating are performed in alternative fashion to mitigate the tracking drift. Experiments on videos have shown robust tracking performance especially when objects contain significantpose changes accompanied with long-term partial occlusions. Evaluations and comparisons with two existing methods provide further support to the proposed method.
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6. |
- Liu, Yang, et al.
(author)
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Movement Status Based Vision Filter for RoboCup Small-Size League
- 2012
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In: Advances in Automation and Robotics, Vol. 2. - Berlin, Heidelberg : Springer. - 9783642256455 - 9783642256462 ; , s. 79-86
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Book chapter (other academic/artistic)abstract
- Small-size soccer league is a division of the RoboCup (Robot world cup) competitions. Each team uses its own designed hardware and software to compete with othersunder defined rules. There are two kinds of data which the strategy system will receive from the dedicated server, one of them is the referee commands, and the other one is vision data. However, due to the network delay and the vision noise, we have to process the data before we can actually use it. Therefore, a certain mechanism is needed in this case.Instead of using some prevalent and complex algorithms, this paper proposes to solve this problem from simple kinematics and mathematics point of view, which can be implemented effectively by hobbyists and undergraduate students. We divide this problem by the speed status and deal it in three different situations. Testing results show good performance with this algorithm and great potential in filtering vision data thus forecasting actual coordinates of tracking objects.
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7. |
- ur Réhman, Shafiq, 1978-
(author)
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Expressing emotions through vibration for perception and control
- 2010
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Doctoral thesis (other academic/artistic)abstract
- This thesis addresses a challenging problem: “how to let the visually impaired ‘see’ others emotions”. We, human beings, are heavily dependent on facial expressions to express ourselves. A smile shows that the person you are talking to is pleased, amused, relieved etc. People use emotional information from facial expressions to switch between conversation topics and to determine attitudes of individuals. Missing emotional information from facial expressions and head gestures makes the visually impaired extremely difficult to interact with others in social events. To enhance the visually impaired’s social interactive ability, in this thesis we have been working on the scientific topic of ‘expressing human emotions through vibrotactile patterns’. It is quite challenging to deliver human emotions through touch since our touch channel is very limited. We first investigated how to render emotions through a vibrator. We developed a real time “lipless” tracking system to extract dynamic emotions from the mouth and employed mobile phones as a platform for the visually impaired to perceive primary emotion types. Later on, we extended the system to render more general dynamic media signals: for example, render live football games through vibration in the mobile for improving mobile user communication and entertainment experience. To display more natural emotions (i.e. emotion type plus emotion intensity), we developed the technology to enable the visually impaired to directly interpret human emotions. This was achieved by use of machine vision techniques and vibrotactile display. The display is comprised of a ‘vibration actuators matrix’ mounted on the back of a chair and the actuators are sequentially activated to provide dynamic emotional information. The research focus has been on finding a global, analytical, and semantic representation for facial expressions to replace state of the art facial action coding systems (FACS) approach. We proposed to use the manifold of facial expressions to characterize dynamic emotions. The basic emotional expressions with increasing intensity become curves on the manifold extended from the center. The blends of emotions lie between those curves, which could be defined analytically by the positions of the main curves. The manifold is the “Braille Code” of emotions. The developed methodology and technology has been extended for building assistive wheelchair systems to aid a specific group of disabled people, cerebral palsy or stroke patients (i.e. lacking fine motor control skills), who don’t have ability to access and control the wheelchair with conventional means, such as joystick or chin stick. The solution is to extract the manifold of the head or the tongue gestures for controlling the wheelchair. The manifold is rendered by a 2D vibration array to provide user of the wheelchair with action information from gestures and system status information, which is very important in enhancing usability of such an assistive system. Current research work not only provides a foundation stone for vibrotactile rendering system based on object localization but also a concrete step to a new dimension of human-machine interaction.
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8. |
- Romero, Mario, 1973-, et al.
(author)
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Evaluating Video Visualizations of Human Behavior
- 2011
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In: Proceedings of the SIGCHI Conference on Human Factors in Computing Systems. - New York, NY, USA : ACM. ; , s. 1441-1450
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Conference paper (peer-reviewed)abstract
- Previously, we presented Viz-A-Vis, a VIsualiZation of Activity through computer VISion [17]. Viz-A-Vis visualizes behavior as aggregate motion over observation space. In this paper, we present two complementary user studies of Viz-A-Vis measuring its performance and discovery affordances. First, we present a controlled user study aimed at comparatively measuring behavioral analysis preference and performance for observation and search tasks. Second, we describe a study with architects measuring discovery affordances and potential impacts on their work practices. We conclude: 1) Viz-A-Vis significantly reduced search time; and 2) it increased the number and quality of insightful discoveries.
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9. |
- Dobnik, Simon, 1977
(author)
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Coordinating spatial perspective in discourse
- 2012
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In: Proceedings of the Workshop on Vision and Language 2012 (VL'12): The 2nd Annual Meeting of the EPSRC Network on Vision and Language.
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Conference paper (other academic/artistic)abstract
- We present results of an on-line data collection experiment where we investigate the assignment and coordination of spatial perspective between a pair of dialogue participants situated in a constrained virtual environment.
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10. |
- Höglund, Lars, 1946, et al.
(author)
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Maskininlärningsbaserad indexering av digitaliserade museiartefakter - projektrapport
- 2012
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Reports (other academic/artistic)abstract
- Projektet har genomfört försök med maskinbaserad analys och maskininlärning för automatisk indexering och analys av bilder som stöd för registrering av föremål i museibestånd. Resultaten visar att detta är möjligt för avgränsade delmängder i kombination med maskininlärning som stöd för, men inte som ersättning för, manuell analys. Projektet har också funnit behov av utveckling av ett användargränssnitt för både text och bildsökning och utvecklat en prototyplösning för detta, vilket finns dokumenterat i denna rapport och i ett separat appendix till rapporten. Materialet utgör grundunderlag för implementeringar som innebär utökade sökmöjligheter, effektivare registrering samt ett användarvänligt gränssnitt. Arbetet ligger i framkant av forskningsområdets resultat och etablerade metoder och kombinerar statististiska, lingvistiska och datavetenskapliga metoder. Se länk till rapport och även länk till appendix längre ned.
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