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Sensitivity analysis of different sensing strategies for electrical impedance imaging of two-phase flows

JOURNAL OF ELECTRONIC IMAGING 2001年第3期10卷 641-645页

作者： Figueroa, TP Seleghim, P Univ Sao Paulo Escola Engn Sao Carlos Dept Engn Mecan Nucleo Engn Term & Fluidos BR-13566590 Sao Carlos SP Brazil

Due to practical considerations, electrical fields and other soft field sensing techniques are convenient to use in process tomography applications. However, most of the reconstruction algorithms were first developed for hard sensing fields that approximate soft fields only in the situation of low electrical contrast. A less restrictive reconstruction method can be developed by refining the qualitative images of a direct imaging probe, but the boundary measurements must be sensitive to changes in the distribution of the electrical properties of the flow. This paper addresses the issue and presents a sensitivity analysis of different excitation strategies and their applicability in a reconstruction algorithm such as described above. Results confirm that classical excitation strategies suffer from a major lack of sensitivity and that new ones must be developed, possibly based on the optimization of the excitation profiles or on multisensing techniques. (C) 2001 SPIE and IS&T.

关键词： Electrodes Tomography Numerical simulations Analytical research Reconstruction algorithms Standards development algorithm development Automatic control Image processing Surface plasmons

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Two-dimensional control systems: Learning from implementations

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JOURNAL OF ELECTRONIC IMAGING 2001年第3期10卷 661-668页

作者： Duncan, SR Univ Oxford Dept Engn Sci Oxford OX1 3PJ England

The design of sensing and control systems for two-dimensional industrial processes such as paper making, plastic film extrusion and metal rolling, has drawn extensively upon concepts from two-dimensional signal processing and image processing. The performance of two-dimensional control systems is discussed in terms of spatial and dynamic bandwidths and is illustrated by examples from the control of cross-directional variations on a plastic film extrusion line. By relating these bandwidths to the specification of the required quality of the finished film and typical disturbances that enter the process, specifications are developed for the design of the actuators, the sensing system and the control algorithm. It is shown that the current generation of control systems is not suitable for controlling variations over small areas of sheet, but a system which regulates over much smaller areas could be developed using recent developments in sensors and two-dimensional control algorithms. (C) 2001 SPIE and IS&T.

关键词： Control systems Actuators Critical dimension metrology Control systems design Sensors Sensing systems Laser induced plasma spectroscopy algorithm development Imaging systems Image processing

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Font clustering and cluster identification in document images

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JOURNAL OF ELECTRONIC IMAGING 2001年第2期10卷 418-430页

作者： Öztürk, S Sankur, B Abak, AT Bogazici Univ Dept Elect Elect Engn TR-80815 Bebek Turkey Marmara Res Ctr Informat Technol Res Inst Gebze Kocaeli Turkey

In this work clustering and recognition problem of fonts in document images is addressed. Various font features and their clustering behavior are investigated. Font clustering is implemented both from shape similarity or from OCR performance points of view. A font recognition algorithm is developed that can identify the font group or the individual font from which a text was created. (C) 2001 SPIE and IS&T.

关键词： Optical character recognition Raster graphics Detection and tracking algorithms algorithm development Feature extraction Binary data Image segmentation Databases Distance measurement Distortion

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Ranked data analysis of a gamut-mapping experiment

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JOURNAL OF ELECTRONIC IMAGING 2001年第2期10卷 399-408页

作者： Millen, BA Bunge, J Handley, JC Ohio State Univ Dept Stat Columbus OH 43210 USA Cornell Univ Dept Social Stat Ithaca NY 14853 USA Xerox Res & Technol Digital Imaging Technol Ctr Webster NY 14580 USA

We analyze data from a gamut-mapping experiment using several statistical procedures for ranked data. In this experiment six gamut-mapping algorithms were applied to six different images and the results were ranked by 31 judges according to how well the images matched an original. We fitted two distance-based statistical models to the data: both analyses showed that aggregate preference among the six algorithms depended on the image viewed. Based on the first model we classified the images into four classes or clusters. We applied unidimensional unfolding, a technique from mathematical psychology, to extract latent reference frames upon which judges plausibly ordered the algorithms. Four color experts gave interpretations of the derived reference frames. We used the second model to generate confidence sets for the consensus rankings, and another cluster analysis. (C) 2001 SPIE and IS&T.

关键词： Data modeling Statistical analysis Mathematical modeling Statistical modeling Data analysis Distance measurement Analytical research algorithm development Data centers Statistical methods

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Arithmetic gain of the Lifting Scheme

Arithmetic gain of the Lifting Scheme

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Conference on Wavelets - Applications in Signal and Image Processing IX

作者： Reichel, J VisioWave Corp R&D Ctr CH-1024 Ecublens Switzerland

ISBN: (纸本)0819441929

The Lifting Scheme (LS) is a very efficient implementation of the Discrete Wavelet transform (DWT). In this work we compute the arithmetic gain realized when the LS is used instead of conventional filter banks. It is shown that contrary to was was presented in the original work from Sweldens again of four is possible. However the LS should be used with care as it can increase the memory bandwidth. Some implementations are presented together with their impact on the bandwidth.

关键词： Discrete wavelet transforms Optical filters Finite impulse response filters Linear filtering Image filtering Electronic filtering Image compression algorithm development Matrices Wavelets

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Sensitivity analysis of different sensing strategies for electrical impedance imaging of two-phase flows

Sensitivity analysis of different sensing strategies for ele...

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Conference on Process Imaging for Automatic Control

作者： Figueroa, TP Seleghim, P Univ Sao Paulo Escola Engn Sao Carlos Dept Engn Mecan Nucleo Engn Term & Fluidos BR-13566590 Sao Carlos SP Brazil

ISBN: (纸本)0819438537

关键词： Electrodes Tomography Numerical simulations Analytical research Image processing Reconstruction algorithms algorithm development Diagnostics Electromagnetic radiation Surface plasmons

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Temperature and emissivity retrieval from DAIS Data:: application to the DAISEX campaigns in Colmar (France) and Barrax (Spain)

Temperature and emissivity retrieval from DAIS Data:: applic...

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Conference on Image and Signal Processing for Remote Sensing VI

作者： Sobrino, JA Laporta, S Reíllo, S Nerry, F Univ Valencia Fac Phys Dept Thermodynam E-46100 Burjassot Spain

ISBN: (纸本)081943826X

In the present paper it is presented a methodology to calculate the surface temperature (ST) from the combination of the radiometric temperature in two different DAIS (Digital Airborne Imaging Spectrometer) thermal bands using split-window (sw) method. To get this objective the MODTRAN 3.5 radiative transfer code was used to predict radiance for DAIS channels 74 (8.75 mum), 75 (9.65 mum), 76 (10.48 mum), 77 (11.27 mum), 78 (12.00 mum) and 79 (12.67 mum) at different aircraft altitudes with the appropriate channel filter functions. In order to analyse atmospheric effects a set of radiosoundings that cover the variability of surface temperature and water vapour concentration on a world-wide scale was used. Once the algorithm has been obtained, an application to DAIS images obtained in Colmar (France) and Barrax (Spain) during the DAISEX'98 and '99 ( Data Airborne Imaging Spectrometer Experiment) campaigns framework has been made. Finally a comparison between the surface temperature obtained from DAIS data, previously corrected from the atmospheric and emissivity effect, and the simultaneous in-situ measurements, is included. The results show that the proposed theoretical sw are able to produce land surface temperature with a standard deviation lower than 1 K. This is in good agreement with the validation results obtained from DAISEX campaign.

关键词： Temperature metrology Soil science algorithm development Sensors Airborne remote sensing Computer simulations Data modeling Spectroscopy Stereolithography Ozone

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Automatic registration of sequential ladar imagery

Automatic registration of sequential ladar imagery

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11th Conference on Automatic Target Recognition

作者： Van Nevel, AJ USN Air Warfare Ctr China Lake CA 93555 USA

ISBN: (纸本)0819440744

In this work we present an algorithm used to automatically register a sequence of ladar images taken from a sensor flying a known flight path. The registration is performed with no human operator intervention. The resulting mosaic is accurate to one pixel. The algorithmic approach was developed in such a way to allow for near real time processing. The initial method can be extended to registration of multiple views of a scene, with four degrees of freedom (translation and in plane rotation). In this work we will restrict ourselves to rigid body transformations. The registered mosaic is an important step in geolocation using a reference digital elevation map, and will be explored in future work.

关键词： LIDAR Image registration Sensors algorithm development 3D image processing 3D metrology Defense technologies Feature extraction Visualization Warfare

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Building a million beacon map

Building a million beacon map

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Sensor Fusion and Decentralized Control in Robotic Systems IV Conference

作者： Julier, SJ Uhlmann, JK IDAK Ind Jefferson City MO 65109 USA

ISBN: (纸本)0819442992

Many future missions for mobile robots demand multi-robot systems which are capable of operating in large environments for long periods of time. A critical capability is that each robot must be able to localise itself. However, GPS cannot be used in many environments (such as within city streets, under water, indoors, beneath foliage or extra-terrestrial robotic missions) where mobile robots are likely to become commonplace. A widely researched alternative is Simultaneous Localization and Map Building (SLAM): the vehicle constructs a map and, concurrently, estimates its own position. In this paper we consider the problem of building and maintaining an extremely large map (of one million beacons). We describe a fully distributed, highly scaleable SLAM algorithm which is based on distributed data fusion systems. A central map is maintained in global coordinates using the Split Covariance Intersection (SCI) algorithm. Relative and local maps are run independently of the central map and their estimates are periodically fused with the central map.

关键词： Filtering (signal processing) Mobile robots Data fusion algorithm development Process modeling Robotic systems Sensors Distributed computing Global Positioning System Robotics

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Continuous identification technology

Continuous identification technology

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Conference on algorithms for Synthetic Aperture Radar Imagery VIII

作者： Diemunsch, J AFRL SNAA Wright Patterson AFB OH 45433 USA

ISBN: (纸本)0819440779

The Air Force Research Laboratory's Sensor Directorate is developing the next step in target recognition, a continuous identification capability. This capability consists of a wide range of algorithms, sensor modes and technologies that work in concert to contribute to the overall goal of identification of moving as well as stationary targets. Three major pieces of this emerging capability are stationary identification, correlation of this information with tracks and the moving target recognition technologies. Although a brief discussion of each of these pieces will be provided in this paper, the concentration will be on the actual algorithms and technologies of the moving target recognition exploiting High Range Resolution (HRR) radar mode and how this complements Ground Moving Target Indication (GMTI) tracking and Synthetic Aperture Radar (SAR) Automatic Target Recognition (ATR). This paper will expand on the overall continuous ID vision, work performed under several efforts, new sources of HRR data, and how this data will push the state of the art. The advantages of continuous ID should be obvious to the warfighter in many dimensions. As a command and control structure it is very difficult to identify and target time critical targets especially when the identification process is limited to stationary targets. These technologies will provide a wider range of targeting options so the enemy has no sanctuary in moving, setting up and in hiding.

关键词： Synthetic aperture radar Automatic target recognition Target recognition Detection and tracking algorithms Doppler effect Radar algorithm development Data modeling Model-based design Sensors

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