Sökning: "belief propagation"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden belief propagation.

1. 1. Nonparametric Message Passing Methods for Cooperative Localization and Tracking

   Författare :Vladimir Savic; Santiago Zazo; Spain Technical University of Madrid; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cooperative localization; tracking; wireless sensor networks; message passing; particle filtering; belief propagation; RFID;

   Sammanfattning : The objective of this thesis is the development of cooperative localization and tracking algorithms using nonparametric message passing techniques. In contrast to the most well-known techniques, the goal is to estimate the posterior probability density function (PDF) of the position of each sensor. LÄS MER

3. 2. Simplified Graphical Approaches for CDMA Multi-User Detection, Decoding and Power Control

   Författare :Peng Hui Tan; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; code-division multiple access; belief propagation; large system analysis; iterative decoding; multiuser detection; power control;

   Sammanfattning : The individual optimal detector for code-division multiple-access (CDMA) systems is based on the marginal a posteriori distribution of the transmitted bits. The marginalization is in general hard since a summation is required, which grows exponentially in scope with the number of active users. LÄS MER

4. 3. Finite-Length Scaling Laws for Spatially-Coupled LDPC Codes

   Författare :Roman Sokolovskii; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; belief propagation decoding; spatially-coupled LDPC codes; window decoding; codes-on-graphs; finite-length code performance;

   Sammanfattning : This thesis concerns predicting the finite-length error-correcting performance of spatially-coupled low-density parity-check (SC-LDPC) code ensembles over the binary erasure channel. SC-LDPC codes are a very powerful class of codes; their use in practical communication systems, however, requires the system designer to specify a considerable number of code and decoder parameters, all of which affect both the code’s error-correcting capability and the system’s memory, energy, and latency requirements. LÄS MER

5. 4. Equilibrium and Dynamics on Complex Networkds

   Författare :Gino Del Ferraro; Erik Aurell; Bernard Derrida; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Statistical mechanics; complex networks; spin systems; non equilibrium dynamics; generalized belief propagation; message passing; cavity method; variational approaches; Fysik; Physics;

   Sammanfattning : Complex networks are an important class of models used to describe the behaviour of a very broad category of systems which appear in different fields of science ranging from physics, biology and statistics to computer science and other disciplines. This set of models includes spin systems on a graph, neural networks, decision networks, spreading disease, financial trade, social networks and all systems which can be represented as interacting agents on some sort of graph architecture. LÄS MER

7. 5. Narrowing the gap between network models and real complex systems

   Författare :Alcides Viamontes Esquivel; Martin Rosvall; Joachim Mathiesen; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; complex systems; network science; community detection; model selection; signficance analysis; ergodicity; fysik; Physics;

   Sammanfattning : Simple network models that focus only on graph topology or, at best, basic interactions are often insufficient to capture all the aspects of a dynamic complex system. In this thesis, I explore those limitations, and some concrete methods of resolving them. LÄS MER