Results 1  10
of
88
DETERMINANT MAXIMIZATION WITH LINEAR MATRIX INEQUALITY CONSTRAINTS
"... The problem of maximizing the determinant of a matrix subject to linear matrix inequalities arises in many fields, including computational geometry, statistics, system identification, experiment design, and information and communication theory. It can also be considered as a generalization of the s ..."
Abstract

Cited by 229 (18 self)
 Add to MetaCart
The problem of maximizing the determinant of a matrix subject to linear matrix inequalities arises in many fields, including computational geometry, statistics, system identification, experiment design, and information and communication theory. It can also be considered as a generalization of the semidefinite programming problem. We give an overview of the applications of the determinant maximization problem, pointing out simple cases where specialized algorithms or analytical solutions are known. We then describe an interiorpoint method, with a simplified analysis of the worstcase complexity and numerical results that indicate that the method is very efficient, both in theory and in practice. Compared to existing specialized algorithms (where they are available), the interiorpoint method will generally be slower; the advantage is that it handles a much wider variety of problems.
The bhattacharyya metric as an absolute similarity measure for frequency coded data
 Kybernetika
, 1997
"... A recurring problem that arises throughout the sciences is that of deciding whether two statistical distributions differ or are consistent currently the chisquared statistic is the most commonly used technique for addressing this problem. This paper explains the drawbacks of the chisquared statis ..."
Abstract

Cited by 77 (5 self)
 Add to MetaCart
(Show Context)
A recurring problem that arises throughout the sciences is that of deciding whether two statistical distributions differ or are consistent currently the chisquared statistic is the most commonly used technique for addressing this problem. This paper explains the drawbacks of the chisquared statistic for comparing measurements over large distances in pattern space and suggests that the Bhattacharyya measure can avoid such difficulties. The original interpretation of the Bhattacharyya metric as a geometric similarity measure is reviewed and it is pointed out that this derivation is independent of the use of the Bhattacharyya measure as an upper bound on misclassification in a twoclass problem. The affinity between the Bhattacharyya and Matusita measures is described and we show that the measure is applicable to any distribution of data. We explain that the Bhattacharyya measure is consistent with an assumption of a Poisson generation mechanism for individual measurements in a distribution which is applicable to a frequency (histogram) or probabilistic data set and suggest application of the Bhattacharyya measure to the field of system identification.
Databased mechanistic modelling of environmental,ecological,economic and engineering systems, Environmental Modelling and
 Software
, 1998
"... Abstract: The paper discusses the problems associated with environmental modelling and the need to consider uncertainty in the formulation, identification, estimation and validation of environmental models. It introduces the concept of DataBased Mechanistic (DBM) modelling and contrasts its inducti ..."
Abstract

Cited by 44 (10 self)
 Add to MetaCart
(Show Context)
Abstract: The paper discusses the problems associated with environmental modelling and the need to consider uncertainty in the formulation, identification, estimation and validation of environmental models. It introduces the concept of DataBased Mechanistic (DBM) modelling and contrasts its inductive approach with the hypotheticodeductive approaches that dominate most environmental modelling research at the present time. The major methodological procedures utilized in DBM modelling are outlined and two practical examples illustrate how it has been applied in a hydrological and water quality context. Keynote paper presented at the International Federation on Automatic Control (IFAC) Workshop on Environmental Systems, Tokyo, Japan, August 21st, 2001. 1.
Digital Audio Restoration
 Applications of Digital Signal Processing to Audio and Acoustics
, 1997
"... This chapter is concerned with the application of modern signal processing techniques to the restoration of degraded audio signals. Although attention is focussed on gramophone recordings, film sound tracks and tape recordings, many of the techniques discussed have applications in other areas where ..."
Abstract

Cited by 37 (12 self)
 Add to MetaCart
(Show Context)
This chapter is concerned with the application of modern signal processing techniques to the restoration of degraded audio signals. Although attention is focussed on gramophone recordings, film sound tracks and tape recordings, many of the techniques discussed have applications in other areas where degraded audio signals occur, such as speech transmission, telephony and hearing aids. We aim to provide a wide coverage of existing methodology while giving insight into current areas of research and future trends. 1 Introduction The introduction of high quality digital audio media such as Compact Disk (CD) and Digital Audio Tape (DAT) has dramatically raised general awareness and expectations about sound quality in all types of recordings. This, combined with an upsurge in interest in historical and nostalgic material, has led to a growing requirement for restoration of degraded sources ranging from the earliest recordings made on wax cylinders in the nineteenth century, through disc reco...
Identification Delamination in Composite Beams using Builtin Piezoelectrics
 Part II – An Identification Method,’’ Journal of Intelligent Material Systems and Structures
, 1995
"... *Author to whom correspondence should be addressed. ABSTRACT: An investigation was performed on using piezoelectrics built into laminated composite structures to detect a delamination and estimate its size and location. Previously, a structural model was developed for predicting the output voltages ..."
Abstract

Cited by 29 (0 self)
 Add to MetaCart
(Show Context)
*Author to whom correspondence should be addressed. ABSTRACT: An investigation was performed on using piezoelectrics built into laminated composite structures to detect a delamination and estimate its size and location. Previously, a structural model was developed for predicting the output voltages from the sensors when a delaminated beam was excited by the actuators. In this sequel, a delamination identification method is presented which consists of the structural model, a response comparator and a damage selector. When damage is suspected, the structural model is run repeatedly to predict the changes in response due to different possible delaminations. During these runs, delamination sizes and locations are selected randomly by the damage selector, which is based on an approach similar to the "simulated annealing algorithm " that improves agreement between the measured and calculated responses. In the response comparator, the agreement is quantified by using a weighted quadratic objective function. When the objective function is minimized, the responses agree, and the assumed damage is also a best estimate for the actual delamination dimensions. The method has been tested using responses measured in the laboratory and has successfully identified artificially implanted beam delaminations.
Crestfactor minimization using nonlinear chebyshev approximation methods
 IEEE Trans. Instr. and Meas
, 1991
"... ..."
(Show Context)
Numerical Algorithms For Subspace State Space System Identification (n4sid)
 in Applied and Computational Control, Signals and Circuits
, 1997
"... We present the basic notions on subspace identification algorithms for linear systems. These methods estimate state sequences or extended observability matrices directly from the given data, through an orthogonal or oblique projection of the row spaces of certain block Hankel matrices into the row s ..."
Abstract

Cited by 17 (8 self)
 Add to MetaCart
We present the basic notions on subspace identification algorithms for linear systems. These methods estimate state sequences or extended observability matrices directly from the given data, through an orthogonal or oblique projection of the row spaces of certain block Hankel matrices into the row spaces of others. The extraction of the state space model is then achieved through the solution of a least squares problem. These algorithms can be elegantly implemented using wellknown numerical linear algebra algorithms such as the LQ and singular value decomposition. The paper aims at giving an overview of the methodologies used in time domain subspace identification. A short overview of frequency domain subspace identification results is also presented. 1 INTRODUCTION While at first sight, the class of linear timeinvariant systems with lumped parameters, seems to be rather restricted, it turns out that the inputoutput behavior of many reallife industrial processes, for most practica...
Stochastic, dynamic modelling and signal processing: time variable and state dependent parameter estimation
 Cambridge University Press: Cambridge
, 2000
"... 1999) have discussed an approach to nonstationary and nonlinear signal processing ..."
Abstract

Cited by 14 (4 self)
 Add to MetaCart
1999) have discussed an approach to nonstationary and nonlinear signal processing
CrossCorrelation Analysis of the Dynamics of Methane Emissions From a Boreal Peatland
, 1996
"... The effects of temperature, water table, and precipitation on the methane fluxes from a boreal lowsedge Sphagnura papillosura pine fen were analyzed with statistical cross correlations of daily data. The six measurement sites represented different vegetation surfaces of the mire (hurmnocks, lawn ..."
Abstract

Cited by 14 (3 self)
 Add to MetaCart
The effects of temperature, water table, and precipitation on the methane fluxes from a boreal lowsedge Sphagnura papillosura pine fen were analyzed with statistical cross correlations of daily data. The six measurement sites represented different vegetation surfaces of the mire (hurmnocks, lawns, and fiarks) with increasing moisture. The dynamics were analyzed separately for the eaxly summer (MayJuly) and the late sununer (AugustOctober) periods in addition to the whole summer (MayOctober) period. Methane emissions increased with increasing peat temperature. During the late sununer period, changes in peat temperatures at depths of 20 and 50 cm were reflected in methane enfissions within 2 days. The persistently high water tables during the measurmnent period probably did not reveal the dynanfics between water table fluctuations and methane emissions very clearly. Methane emission levels correlated negatively with depths of the water tables, that is, high methane emissions were associated with low water tables and vice versa. The suppression of methane enfissions by filling the unsaturated gas space during precipitation and the increased release rate caused by a declining water table could explain the result. Methane emissions correlated positively with changes in water tables, that is, a rise in water table increased methane emissions during the early and whole surmner periods. Precipitation increased enfissions with a lag from zero to several days throughout the sunmer. Generally, the estimated responses of methane fluxes to precipitation and changes in water table indicated similar time lags. Methane flux from the fiark surfaces seemed to respond rapidly to rainfall artd changes in water table with a lag of zero or I day. In the lawnlow h...
Model Based Recognition using Pruned Correspondence Search
 IEEE Conf. on Computer Vision and Pattern Recognition
, 1990
"... This paper presents a polynomial time algorithm (pruned correspondence search, PCS) for solving a wide class of geometric maximal matching problems, including the problem of recognizing 3D objects from a single 2D image. The PCS algorithm is connected with the geometry of the underlying recognit ..."
Abstract

Cited by 11 (0 self)
 Add to MetaCart
This paper presents a polynomial time algorithm (pruned correspondence search, PCS) for solving a wide class of geometric maximal matching problems, including the problem of recognizing 3D objects from a single 2D image. The PCS algorithm is connected with the geometry of the underlying recognition problem only through calls to a verification algorithm.