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Malguki:: an RSSI based ad hoc location algorithm

MICROPROCESSORS AND MICROSYSTEMS 2004年第8期28卷 403-409页

作者： Arias, J Zuloaga, A Lázaro, J Andreu, J Astarloa, A Univ Basque Country Fac Engn Dept Elect & Telecommun Bilbao 48013 Spain

The problem of finding the location of a node in wireless networks has been a research interest in the last years. In environments where the GPS does not work, the estimation of a node position using only RF signals is not a trivial task. Although some other systems have been proposed so far, using ultrasonic signals, IR, etc. But those require additional hardware that is only to be used for location finding. This article describes an algorithm, which computes the location of a node using noisy distance estimations. Thus, the restriction on distance exactitude can be relaxed and RF signal based distance estimations may be used to estimate the node location. (C) 2004 Elsevier B.V. All rights reserved.

关键词： RSSI location wireless sensor networks robust algorithms

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DYNAMIC STEREO WITH SELF-CALIBRATION

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IEEE TRANSACTIONS ON PATTERN ANALYSIS AND MACHINE INTELLIGENCE 1992年第12期14卷 1184-1189页

作者： TIRUMALAI, AP SCHUNCK, BG JAIN, RC UNIV MICHIGAN ARTIFICIAL INTELLIGENCE LABANN ARBORMI 48109

We present an approach for incremental refinement of disparity maps obtained from a dynamic stereo sequence of a static scene. The approach has been implemented using a binocular stereo vision system mounted on a mobile robot. We present a robust least median of squares (LMS)-based algorithm to recover the camera motion between successive viewpoints, which provides a self-calibration mechanism. The recovered motion is utilized for recursive disparity prediction and refinement using a robust Kalman filter model.

关键词： ACTIVE VISION DEPTH RECOVERY DYNAMIC STEREO ENVIRONMENT MODELING KALMAN FILTERING RECURSIVE ESTIMATION robust algorithms SELF-CALIBRATION SENSOR FUSION 3-D SENSING

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Analytical aspects of tie breaking

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THEORETICAL COMPUTER SCIENCE 2012年 465卷 1-9页

作者： Jacobs, Tobias Natl Inst Informat Principles Informat Div Tokyo Japan

This article describes an analytical framework for reasoning about the issue of tie breaking in algorithm theory. The core of this framework is the concept of robust algorithms. Such kind of algorithms have the convenient property that an arbitrary set of degenerate cases can be ignored without loss of generality during proofs of many important properties, e.g.. runtime, space requirements, feasibility, competitive and approximation ratios. Here degeneracy is defined as a set of problem instances satisfying a certain property, and this property is independent from both the algorithm under consideration and the specific combinatorial problem structure. It turns out that robustness is related to the tie breaking policy of algorithms in two different ways. On the one hand, the set of inputs where a tie actually occurs is typically (but not always) a degenerate case. On the other hand, we show that for any algorithm there is a way to break ties such that it becomes robust. In particular, robustness is guaranteed by any tie breaking strategy that can be interpreted as symbolic perturbation. For many typical algorithms the implicit usage of symbolic perturbation can be easily verified and so the consideration of degenerate cases can be avoided during their analysis. The concept of robustness also gives a theoretical explanation of why tie breaking does often not matter at all. (c) 2012 Elsevier B.V. All rights reserved.

关键词： Perturbation robust algorithms Proof technique Degeneracy

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Minimization algorithms based on supervisor and searcher cooperation

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JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS 2001年第2期111卷 359-379页

作者： Liu, W Dai, YH Univ Kent Canterbury Business Sch Canterbury Kent England Chinese Acad Sci Acad Math & Syst Sci Inst Computat Math & Sci Engn Comp State Key Lab Sci & Engn Comp Beijing Peoples R China

In the present work, we explore a general framework for the design of new minimization algorithms with desirable characteristics, namely, supervisor-searcher cooperation. We propose a class of algorithms within this framework and examine a gradient algorithm in the class. Global convergence is established for the deterministic case in the absence of noise and the convergence rate is studied. Both theoretical analysis and numerical tests show that-the algorithm is efficient for the deterministic case. Furthermore, the fact that there is no line search procedure incorporated in the algorithm seems to strengthen its robustness so that it tackles effectively test problems with stronger stochastic noises. The numerical results for both deterministic and stochastic test problems illustrate the appealing attributes of the algorithm.

关键词： robust algorithms noisy optimization gradient algorithms stochastic approximations

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Recent progress in exact geometric computation

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JOURNAL OF LOGIC AND ALGEBRAIC PROGRAMMING 2005年第1期64卷 85-111页

作者： Li, C Pion, S Yap, CK NYU Courant Inst Math Sci New York NY 10012 USA

Computational geometry has produced an impressive wealth of efficient algorithms. The robust implementation of these algorithms remains a major issue. Among the many proposed approaches for solving numerical non-robustness, exact geometric computation (EGC) has emerged as one of the most successful. This survey describes recent progress in EGC research in three key areas: constructive zero bounds, approximate expression evaluation and numerical filters. (c) 2004 Published by Elsevier Inc.

关键词： exact geometric computation constructive zero bounds non-robustness problems robust algorithms approximate expression evaluation precision-driven computation numerical filters nterval arithmetic C plus plus libraries

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EXTENDING robustNESS AND RANDOMIZATION FROM CONSENSUS TO SYMMETRIZATION algorithms

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SIAM JOURNAL ON CONTROL AND OPTIMIZATION 2015年第4期53卷 2076-2099页

作者： Mazzarella, Luca Ticozzi, Francesco Sarlette, Alain Univ Padua Dipartimento Ingn Informaz I-35131 Padua Italy Dartmouth Coll Dept Phys & Astron Hanover NH 03755 USA PSL Res Univ QUANTIC Project Team INRIA Paris Rocquencourt Paris France Univ Ghent SYSTeMS B-9052 Ghent Belgium

This work interprets and generalizes consensus-type algorithms as switching dynamics leading to symmetrization of some vector variables with respect to the actions of a finite group. We show how the symmetrization framework we develop covers applications as diverse as consensus on probability distributions (either classical or quantum), uniform random state generation, and open-loop disturbance rejection by quantum dynamical decoupling. robust convergence results are explicitly provided in a group-theoretic formulation, both for deterministic and for randomized dynamics. This indicates a way to directly extend the robustness and randomization properties of consensus-type algorithms to more fields of application.

关键词： symmetry groups robust algorithms distributed algorithms consensus random state generation

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MOTION AND STRUCTURE FROM FEATURE CORRESPONDENCES - A REVIEW

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PROCEEDINGS OF THE IEEE 1994年第2期82卷 252-268页

作者： HUANG, TS NETRAVALI, AN AT&T BELL LABS MURRAY HILL NJ 07974 USA

We present a review of algorithms and their performance for determining three-dimensional (3D) motion and structure of rigid objects when their corresponding features are known at different times or are viewed by different cameras. Three categories of problems are considered, depending upon whether the features are two-(2D) or three-dimensional (3D) and the type of correspondence: a) 3D to 3D (i.e., locations of corresponding features in 3D space are known at two different times), b) 2D to 3D (i.e., locations of features in 3D space and their projection on the camera plane are known), and c) 2D to 2D (i.e., projections of features on the camera plane are known at two different times). Features considered include points, straight lines, curved lines, and corners. Emphasis is on problem formulation, efficient algorithms for solution, existence and uniqueness of solutions, and sensitivity of solutions to noise in the observed data. algorithms described have been used in a variety of applications. Some of these are: a) positioning and navigating 3D objects in a 3D world, b) camera calibration, i.e., determining location and orientation of a camera by observing 3D features whose location is known, c) estimating motion and structure of moving objects relative to a camera. We mention some of the mathematical techniques borrowed from algebraic geometry, projective geometry, and homotopy theory that are required to solve these problems, list unsolved problems, and give some directions for future research.

关键词： 2D to 2D correspondence 2D to 3D correspondence 3D motion determination 3D object navigation 3D to 3D correspondence algebraic geometry algorithms camera calibration computational geometry corners curved lines feature correspondences feature extraction homotopy theory imaging geometry motion estimation noise sensitivity path planning points position control positioning problem formulation projective geometry review reviews rigid object structure determination robust algorithms straight lines

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Matched field signal processing in underwater sound channels (Review)

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ACOUSTICAL PHYSICS 2015年第2期61卷 213-230页

作者： Sazontov, A. G. Malekhanov, A. I. Nizhnii Novgorod State Univ Russian Acad Sci Inst Appl Phys Nizhnii Novgorod Russia

The state of the art of matched field hydroacoustic signal processing is described from the viewpoint of estimating the signal parameters in adaptive antenna arrays. The focus is on methods for solving the problem of source localization in an oceanic waveguide under mismatching effects of different nature, caused by disagreement between the received acoustic field and its model. Different approaches to increase the stability of the algorithms for source position estimation are discussed, which allows an increase in their efficiency in natural conditions.

关键词： underwater sound channel matched field processing estimation of parameters deterministic and statistical mismatch robust algorithms source localization

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On the limitations of classical benchmark functions for evaluating robustness of evolutionary algorithms

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APPLIED MATHEMATICS AND COMPUTATION 2010年第9期215卷 3222-3229页

作者： Ahrari, Ali Saadatmand, Mohammad R. Shariat-Panahi, Masoud Atai, Ali A. Univ Tehran Fac Engn Dept Mech Engn Tehran Iran Mobile Commun Co Iran Tehran Iran

Although evolutionary algorithms (EAs) have some operators which let them explore the whole search domain, still they get trapped in local minima when multimodality of the objective function is increased. To improve the performance of EAs, many optimization techniques or operators have been introduced in recent years. However, it seems that these modified versions exploit some special properties of the classical multimodal benchmark functions, some of which have been noted in previous research and solutions to eliminate them have been proposed. In this article, we show that quite symmetric behavior of the available multimodal test functions is another example of these special properties which can be exploited by some EAs such as covariance matrix adaptation evolution strategy (CMA-ES). This method, based on its invariance properties and good optimization results for available unimodal and multimodal benchmark functions, is considered as a robust and efficient method. However, as far as black box optimization problems are considered, no special trend in the behavior of the objective function can be assumed;consequently this symmetry limits the generalization of optimization results from available multimodal benchmark functions to real world problems. To improve the performance of CMA-ES, the Elite search sub-algorithm is introduced and implemented in the basic algorithm. Importance and effect of this modification is illustrated experimentally by dissolving some test problems in the end. (C) 2009 Elsevier Inc. All rights reserved.

关键词： Black box optimization Elite search process robust algorithms Generalization of optimization results Multimodal functions Symmetric behavior

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A geometry modeling system for ray tracing or particle transport Monte Carlo simulation

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COMPUTER PHYSICS COMMUNICATIONS 2003年第1期150卷 21-30页

作者： Popescu, LM Natl Inst R&D Environm Environm Radioact Lab Bucharest 77703 Romania

The principles of a geometry modeling system for ray tracing or Monte Carlo particle transport simulation are presented. The model uses the boundary representation of volumes and was developed using object oriented programming. The surface is adopted as the basic element in the model. Complex structures are described using the derived concept of compound surfaces. Particle tracking exceptions caused by floating point rounding errors are discussed and robust algorithms that use geometrical reasoning to address these problems are presented. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词： Monte Carlo particle transport geometry modeling boundary representation robust algorithms

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