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145,241
ScaleSpace Theory in Computer Vision
, 1994
"... A basic problem when deriving information from measured data, such as images, originates from the fact that objects in the world, and hence image structures, exist as meaningful entities only over certain ranges of scale. "ScaleSpace Theory in Computer Vision" describes a formal theory fo ..."
Abstract

Cited by 616 (21 self)
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A basic problem when deriving information from measured data, such as images, originates from the fact that objects in the world, and hence image structures, exist as meaningful entities only over certain ranges of scale. "ScaleSpace Theory in Computer Vision" describes a formal theory
KTH
"... iii In this thesis we discuss a moduli space of projective curves with a map to a given projective space Pn. The functor CM parametrizes curves, that is, CohenMacaulay schemes of pure dimension 1, together with a finite map to Pn that is an isomorphism onto its image away from a finite set of close ..."
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iii In this thesis we discuss a moduli space of projective curves with a map to a given projective space Pn. The functor CM parametrizes curves, that is, CohenMacaulay schemes of pure dimension 1, together with a finite map to Pn that is an isomorphism onto its image away from a finite set of closed points. We proof that CM is an algebraic space by contructing a scheme W and a representable, surjective and smooth map pi:W → CM. iv Sammanfattning Denna avhandling behandlar ett modulirum för projektiva kurvor med en avbildning till ett givet projektivt rum Pn. Funktorn CM parametriserar par (C, i), där C är en kurva, det vill säga ett ekvidimensionellt schema av dimension 1, och i:C → Pn är en ändlig avbildning som är en isomorfi till sin
Opportunistic Data Structures with Applications
, 2000
"... In this paper we address the issue of compressing and indexing data. We devise a data structure whose space occupancy is a function of the entropy of the underlying data set. We call the data structure opportunistic since its space occupancy is decreased when the input is compressible and this space ..."
Abstract

Cited by 288 (11 self)
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In this paper we address the issue of compressing and indexing data. We devise a data structure whose space occupancy is a function of the entropy of the underlying data set. We call the data structure opportunistic since its space occupancy is decreased when the input is compressible
Communication, KTH
"... Figure 1. (Left and center) Our prototype setup in a surgical room for imageguided surgery where an intraoperational fluoroscope is used for Xray imaging. (Right) Our system exposes the spatial and temporal relationships of the acquired Xrays in an interactive 3D visualization. Imageguided surge ..."
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Figure 1. (Left and center) Our prototype setup in a surgical room for imageguided surgery where an intraoperational fluoroscope is used for Xray imaging. (Right) Our system exposes the spatial and temporal relationships of the acquired Xrays in an interactive 3D visualization. Imageguided surgery (IGS) often depends on Xray imaging, since preoperative MRI, CT and PET scans do not provide an uptodate internal patient view during the operation. Xrays introduce hazardous radiation, but long exposures for monitoring are often necessary to increase accuracy in critical situations. Surgeons often also take multiple Xrays from different angles, as Xrays only provide a distorted 2D perspective from the current viewpoint. We introduce a prototype IGS system that augments 2D Xray images with spatiotemporal information using a motion tracking system, such that the use of Xrays can be reduced. In addition, an interactive visualization allows exploring 2D Xrays in timeline views and 3D clouds where they are arranged according to the viewpoint at the time of acquisition. The system could be deployed and used without timeconsuming calibration, and has the potential to improve surgeons ’ spatial awareness, while increasing efficiency and patient safety. 1.
at CSC, KTH
"... ABSTRACT..................................................................................................................... 6 ACKNOWLEDGEMENTS............................................................................................. 7 ..."
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ABSTRACT..................................................................................................................... 6 ACKNOWLEDGEMENTS............................................................................................. 7
Systems, KTH
"... In this thesis, the gain of using spacetime block codes for one receive antenna and more than two transmit antennas in WCDMA is investigated. A specific 3/4 rate orthogonal spacetime block code for four transmit antennas is simulated and evaluated in comparison with the existing specified open lo ..."
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In this thesis, the gain of using spacetime block codes for one receive antenna and more than two transmit antennas in WCDMA is investigated. A specific 3/4 rate orthogonal spacetime block code for four transmit antennas is simulated and evaluated in comparison with the existing specified open loop scheme in WCDMA. The two systems are compared for different channel models: a nondispersive channel with Rayleigh fading and different antenna correlation, and a multipath channel with Rayleigh fading and different path correlation. The receiver is a Rake receiver, perfectly estimated channel is assumed. The simulation results show a significant improvement for four transmit antennas for higher SNR values. The overall performance is highly dependent on the spreading code properties, which will affect both a system with two antennas and a system with four antennas. However, the simulations show that the two systems are equally sensitive in this aspect. Investigation of the effects of antenna correlation shows that the fourantenna configuration is more sensitive than the
kth bond
, 2002
"... Copyright line will be provided by the publisher The quantum Heisenberg model belongs to the most intensively studied models in statistical mechanics (see [1] and references therein), since it exhibits very interesting quantum phenomena. However, due to the mathematical complexities related to the q ..."
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Copyright line will be provided by the publisher The quantum Heisenberg model belongs to the most intensively studied models in statistical mechanics (see [1] and references therein), since it exhibits very interesting quantum phenomena. However, due to the mathematical complexities related to the quantum nature of the model, only few exact results have been obtained in this field so far. Owing to this fact, the main aim of this work is to introduce a new statistical model, which is exactly solvable for planar lattices and simultaneously exhibits interesting quantum properties. The model to be investigated here consists of Ising and Heisenbergtype atoms regularly distributed on planar doubly decorated lattices, as it is depicted in Fig. 1 for the case of the square lattice. In order to derive the exact results for the model under investigation, it is very convenient to express the total Hamiltonian in the form ˆ Hd = ∑Nq/2 k=1 ˆ Hk, where the summation is carried out over all the bonds of the original (undecorated) lattice, N denotes the total number of the Isingtype atoms and q is the coordination number of the original (undecorated) lattice. The bond Hamiltonian ˆ Hk is given by (see Fig. 1) ˆHk = −J ∆ ( ˆ S x k1 ˆ S x k2 + ˆ S y
Supervisor at KTH:
"... iAbstract The present work aims to find a good way to automatically trace the velocity profile in vessels shown in continuous wave Doppler spectrograms, replacing the more traditional manual tracing, easy to perform but rich in drawbacks. Different methods of preprocessing this kind of images in or ..."
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iAbstract The present work aims to find a good way to automatically trace the velocity profile in vessels shown in continuous wave Doppler spectrograms, replacing the more traditional manual tracing, easy to perform but rich in drawbacks. Different methods of preprocessing this kind of images in order to prepare the edge detection step are presented. Various techniques, taken from the literature or newly created, are tested on a set of 18 CW Doppler spectrograms. The main purpose is to understand which is the best strategy to put into practice, remembering that the goal is to get the maximum velocity envelope, or the mean velocity in the vessel. Two main strategies are tested: a mild preprocessing before edge detection, followed by an edge linking step to fill the gaps in the extracted contour, or a stronger preprocessing that guarantees a continuous contour without further operations. A comparison is made on the obtained results and it is shown that the two approaches are somehow complementary in their pros and cons. In further work, the strengths of the two strategies should be combined in a hybrid method that would guarantee a good compromise between continuity of edges and mathematicalbased detection of boundaries.
Secure Computation of the kthRanked Element
 In Avdances in Cryptology  Proc. of Eurocyrpt ’04
, 2004
"... Given two or more parties possessing large, confidential datasets, we consider the problem of securely computing the k of the datasets, e.g. the median of the values in the datasets. We investigate protocols with sublinear computation and communication costs. In the twoparty case, we show tha ..."
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Cited by 60 (7 self)
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that the k ranked element can be computed in log k rounds, where the computation and communication costs of each round are O(log M), where log M is the number of bits needed to describe each element of the input data.
Results 1  10
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145,241