References of "2009"
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See detailHow to write if you cannot write: collaborative literacy in a Gambian village
Juffermans, Kasper UL

in van de Craats, Ineke; Kurvers, Jeanne (Eds.) Low-educated adult second language and literacy acquisition: Proceedings of the 4th symposium in Antwerp (2009)

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See detail3D Skeleton based Head Detection and Tracking using Range Images
Devarakota, Pandu Ranga Rao UL; Castillo-Franco, Marta; Ginhoux, Romuald et al

in IEEE Transactions on Vehicular Technology (2009), 58(8), 4064-4077

Vision-based 3-D head detection and tracking systems have been studied in several applications like video surveillance, face-detection systems, and occupant posture analysis. In this paper, we present the ... [more ▼]

Vision-based 3-D head detection and tracking systems have been studied in several applications like video surveillance, face-detection systems, and occupant posture analysis. In this paper, we present the development of a topology-based framework using a 3-D skeletal model for the robust detection and tracking of a vehicle occupant's head position from low-resolution range image data for a passive safety system. Unlike previous approaches to head detection, the proposed approach explores the topology information of a scene to detect the position of the head. Among the different available topology representations, the Reeb graph technique is chosen and is adapted to low-resolution 3-D range images. Invariance of the graph under rotations is achieved by using a Morse radial distance function. To cope with the particular challenges such as the noise and the large variations in the density of the data, a voxel neighborhood connectivity notion is proposed. A multiple-hypothesis tracker (MHT) with nearest-neighbor data association and Kalman filter prediction is applied on the endpoints of the Reeb graph to select and filter the correct head candidate out of Reeb graph endpoints. A systematic evaluation of the head detection framework is carried out on full-scale experimental 3-D range images and compared with the ground truth. It is shown that the Reeb graph topology algorithm developed herein allows the correct detection of the head of the occupant with only two head candidates as input to the MHT. Results of the experiments demonstrate that the proposed framework is robust under the large variations of the scene. The processing requirements of the proposed approach are discussed. It is shown that the number of operations is rather low and that real-time processing requirements can be met with the proposed method. [less ▲]

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See detailAxiomatizations of quasi-polynomial functions on bounded chains
Couceiro, Miguel UL; Marichal, Jean-Luc UL

in Aequationes Mathematicae (2009), 78(1-2), 195-213

Two emergent properties in aggregation theory are investigated, namely horizontal maxitivity and comonotonic maxitivity (as well as their dual counterparts) which are commonly defined by means of certain ... [more ▼]

Two emergent properties in aggregation theory are investigated, namely horizontal maxitivity and comonotonic maxitivity (as well as their dual counterparts) which are commonly defined by means of certain functional equations. We completely describe the function classes axiomatized by each of these properties, up to weak versions of monotonicity in the cases of horizontal maxitivity and minitivity. While studying the classes axiomatized by combinations of these properties, we introduce the concept of quasi-polynomial function which appears as a natural extension of the well-established notion of polynomial function. We give further axiomatizations for this class both in terms of functional equations and natural relaxations of homogeneity and median decomposability. As noteworthy particular cases, we investigate those subclasses of quasi-term functions and quasi-weighted maximum and minimum functions, and provide characterizations accordingly. [less ▲]

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See detailBerezin-Toeplitz quantization of moduli spaces
Schlichenmaier, Martin UL

Scientific Conference (2009, October)

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See detailInterdisciplinary cooperation on media effects
Steffgen, Georges UL

Presentation (2009, October)

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See detailAssociation between goal orientation and the means as well as the outcomes of a goal
Mustafic, Maida UL; Freund, Alexandra M.

Poster (2009, October)

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See detailMusikerziehung als Instrument ideologischer Indoktrinierung in der DDR
Sagrillo, Damien UL

Scientific Conference (2009, September 30)

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See detailOn the physical security of cryptographic implementations
Rivain, Matthieu UL

Doctoral thesis (2009)

In modern cryptography, an encryption system is usually studied in the so-called black-box model. In this model, the cryptosystem is seen as an oracle replying to message encryption (and/or decryption ... [more ▼]

In modern cryptography, an encryption system is usually studied in the so-called black-box model. In this model, the cryptosystem is seen as an oracle replying to message encryption (and/or decryption) queries according to a secret value: the key. The security of the cryptosystem is then defined following a simple game. An adversary questions the oracle about the encryption (and/or decryption) of messages of its choice and, depending on the answers, attempts to recover the value of the secret key (or to encrypt/decrypt a message for which he did not query the oracle). If by following an optimal strategy the adversary only has a negligible chance of winning, the system is considered as secure. Several cryptosystems have been proved secure in the black-box model. However, this model is not always sufficient to ensure the security of a cryptosystem in practice. Let us consider the example of smart cards which are used as platforms for cryptosystems in various applications such as banking, access control, mobile telephony, pay TV, or electronic passport. By the very nature of these applications, a cryptosystem embedded on a smart card is physically accessible to potential attackers. This physical access invalidates the modeling of the cryptosystem as a simple encryption oracle since it allows the adversary to observe and disrupt its physical behavior. New attacks then become possible which are known as physical cryptanalysis. Physical cryptanalysis includes two main families of attacks: side channel attacks and fault attacks. The purpose of side channel attacks is to analyze the different physical leakages of a cryptographic implementation during its computation. Chief among these rank timing, power consumption, and electromagnetic radiation. Observing these so-called side channels provides sensitive information about the cryptographic computation. The secret key value can then be easily recovered by statistical treatment although the cryptosystem is secure in the black-box model. The access to a cryptographic implementation enables more than a simple observation of its physical behavior; it is also possible to disrupt its computation. Working on this assumption, fault attacks consist in corrupting cryptographic computations so that they produce erroneous results. Surprisingly, these results can be used in order to recover information about the secret key. This thesis focuses on physical cryptanalysis as well as on the secure implementation of cryptographic primitives. We examine in the first part side channel attacks from a theoretical viewpoint. Various techniques of attack based on different statistical tools are addressed. We analyze their success rate, we compare their efficiency and we propose some improvements. Our analyses are illustrated by results of simulated attacks as well as practical attacks on smart cards. The second part of this thesis is devoted to one of the most widely used countermeasures to side channel attacks: data masking. Our investigations concentrate on generic masking schemes for block ciphers such as the encryption standards DES and AES. We analyze existing schemes, exhibiting some attacks against certain of them and we propose new designs. The third and last part of this thesis deals with fault attacks. First, we describe a new attack on the DES cipher which exhibits some requirements to its secure implementation. We then provide a case study based on the RSA cryptosystem where we propose a new countermeasure which can also be applied to secure any exponentiation algorithm. We finally address an important issue for practical security: the implementation of coherence checks. [less ▲]

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See detailInternationalisierte Migration in den ländlichen Räumen – Auswirkungen der Globalisierung am Beispiel des Saarlandes
Nienaber, Birte UL; Frys, Wioletta

Scientific Conference (2009, September 20)

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See detailGegenwart und Perspektiven der Geographie in Deutschland
Nienaber, Birte UL

Conference given outside the academic context (2009)

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See detailNumerical integration over arbitrary surfaces in partition of unity finite elements
Natarajan, Sundararajan; dal Pont, Stefano; Hung, Nguyen-Xuan et al

Scientific Conference (2009, September)

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See detailLokale Schwerefeldbestimmung mit Hilfe der Randelementemethode und radialer Basisfunktionen
Weigelt, Matthias UL; Keller, W.; Antoni, M.

Scientific Conference (2009, September)

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See detailDer Einfluss von Gerechtigkeitswahrnehmungen von Studierenden auf deren Hochschulbildung
König, Andreas UL; Gollwitzer, Mario; Steffgen, Georges UL

Scientific Conference (2009, September)

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See detailLänderbericht Luxemburg: Weiterentwicklung der standardisierten Tests
Fischbach, Antoine UL; Brunner, Martin UL

Presentation (2009, September)

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See detailGrenzüberschreitende Raumkonstruktionen am Beispiel des Grenzgängerwesens in der Großregion
Wille, Christian UL

Scientific Conference (2009, September)

Detailed reference viewed: 58 (0 UL)