The choice of the path computation algorithm is a key factor to design efficient traffic engineering strategies in multi-protocol label switching networks and different approaches have been proposed in the literature....
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The choice of the path computation algorithm is a key factor to design efficient traffic engineering strategies in multi-protocol label switching networks and different approaches have been proposed in the literature. The effectiveness of a path computation algorithm should be evaluated against its ability to optimise the utilisation of network resources as well as to satisfy both current and future label switched paths allocation requests. Although powerful and flexible simulation tools might be useful to assist a network manager in the selection of proper algorithms, state-of-the-art simulators and network planning tools do not currently offer a suitable support. This study deals with the design and performance evaluation of multi-constraints path computation algorithms. To this aim, ad hoc software modules have been developed and integrated within the MTENS simulator. New single-path and multi-path computation algorithms have been proposed and compared in terms of number of accepted requests, success probability, network resources utilisation and execution time. Finally, some guidelines and recommendations for the selection of path computation algorithms have also been provided.
This letter presents a novel algorithm for automated building detection from light detection and ranging (lidar) point-clouds. The algorithm takes advantage of a marked point process to model the locations of building...
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This letter presents a novel algorithm for automated building detection from light detection and ranging (lidar) point-clouds. The algorithm takes advantage of a marked point process to model the locations of buildings and their geometries. A Bayesian paradigm is used to obtain a posterior distribution for the marked point process. A Reversible Jump Markov Chain Monte Carlo (RJMCMC) algorithm is implemented for simulating the posterior distribution. Finally, the maximum a posteriori (MAP) scheme is used to obtain an optimal building detection. The results obtained on a set of lidar point-clouds demonstrate the efficiency of the proposed algorithm in automated detection of buildings in complex residential areas.
We initiate a thorough study of distributed property testingproducing algorithms for the approximation problems of property testing in the CONGEST model. In particular, for the so-called dense graph testing model we e...
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We initiate a thorough study of distributed property testingproducing algorithms for the approximation problems of property testing in the CONGEST model. In particular, for the so-called dense graph testing model we emulate sequential tests for nearly all graph properties having 1-sided tests, while in the general model we obtain faster tests for triangle-freeness and cycle-freeness, and in the sparse model we obtain a faster test for bipartiteness. In addition, we show a logarithmic lower bound for testing bipartiteness and cycle-freeness, which holds even in the stronger LOCAL model. In most cases, aided by parallelism, the distributed algorithms have a much shorter running time than their counterparts from the sequential querying model of traditional property testing. More importantly, the distributed algorithms we develop for testing graph properties are in many cases much faster than what is known for exactly deciding whether the property holds. The simplest property testing algorithms allow a relatively smooth transition to the distributed model. For the more complex tasks we develop new machinery that may be of independent interest.
The design and implementation of a reconfigurable data acquisition system for a digital relay for power system protection applications are described. A 33% power saving and 31% area reduction are recorded when a modif...
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The design and implementation of a reconfigurable data acquisition system for a digital relay for power system protection applications are described. A 33% power saving and 31% area reduction are recorded when a modified flash analogue-to-digital converter is employed. A further 98% data rate reduction is achieved when the reconfigurable algorithm is applied, enabling an improvement in system efficiency.
Several of edn's recent multimedia articles have pointed out the bloatedsizes of high-fidelity audio files and the consequent appeal of compressing them in lossless orlossy ways for storage and transmission. In co...
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Several of edn's recent multimedia articles have pointed out the bloatedsizes of high-fidelity audio files and the consequent appeal of compressing them in lossless orlossy ways for storage and transmission. In comparison to video, though, uncompressed audio seemsdownright diminutive. Consider the following uncompressed-video bit-rate examples. (Multiply by 60and divide by 8 to get the required per-minute storage capacity in bytes.): 1. Cellular phones: 15frames/sec, 8-bit color, QCIF (176x 144-pixel) res-olution=3.1 Mbps; 2. PDAs: 30 frames/sec, 16-bitcolor, CIF (352x288-pixel) resolution= 48.7 Mbps; 3. PCs: 30 frames/sec, 24-bit color, VGA(640x480-pixel) resolution 221.2 Mbps; 4. HDTV: 60 frames/sec, 24-bit color, 720P (1280x720-pixel,progressive-scan) resolution=1.4 Gbps (1000 times higher than the audio-CD bit rate); 5. Digitalcinema: 24 frames/sec, 30-bit color, 1080P (1920 x1080-pixel, progressive-scan) resolution=1.5 Gbps.
A new and efficient multiscale model for the segmentation of synthetic aperture radar imagery namely the mixture multiscale autoregressive (MMAR) model, is presented. The estimation of parameters is easily performed v...
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A new and efficient multiscale model for the segmentation of synthetic aperture radar imagery namely the mixture multiscale autoregressive (MMAR) model, is presented. The estimation of parameters is easily performed via expectation maximisation algorithm. Experimental results of the MMAR model are proposed and compared with those of previous methods.
An introduction is presented in which the editor discusses various articles within the issue on topics including the conceptual modeling of meme complexes, evaluating a quantum memetic algorithm (QMA), and determining...
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An introduction is presented in which the editor discusses various articles within the issue on topics including the conceptual modeling of meme complexes, evaluating a quantum memetic algorithm (QMA), and determining the motion of humanoid robots by using multivalued decision diagrams (MDDs).
An introduction is presented in which the editors discuss various reports within the issue on topics including visual matching algorithms on mobile device, location discriminative visual vocabulary for location recogn...
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An introduction is presented in which the editors discuss various reports within the issue on topics including visual matching algorithms on mobile device, location discriminative visual vocabulary for location recognition, and video rectification and stabilization for video quality enhancement.
We prove that the problem of recognition of the existence of solutions as rational functions for linear homogeneous partial differential or difference equations with polynomial coefficients is algorithmically undecida...
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We prove that the problem of recognition of the existence of solutions as rational functions for linear homogeneous partial differential or difference equations with polynomial coefficients is algorithmically undecidable.
Point-based object representations are a powerful alternative to traditional polygonal object representations. Capturing 3D geometry is a mission-critical content acquisition technique in application domains such as v...
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Point-based object representations are a powerful alternative to traditional polygonal object representations. Capturing 3D geometry is a mission-critical content acquisition technique in application domains such as virtual reality, CAD/CAM, and physical asset management. An important step in capturing models of real objects from a set of still images or video sequences is scene calibration, which consists of obtaining the configuration of the camera's intrinsic parameters--focal length, principal point, and optical aberrations, for example--as well as extrinsic parameters-3D position and orientation relative to the object. A major problem is calibrating long image sequences with many feature occlusions, which is the case for objects on rotating platforms. Furthermore, in continuous sequences, consecutive frames tend to reflect few scene changes. A good feature-tracking algorithm provides a solid base for a robust camera calibration phase. The calibration phase is one of the most important components of a passive 3D capturing system.
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