07.02.2013 Views

Issue 10 Volume 41 May 16, 2003

Issue 10 Volume 41 May 16, 2003

Issue 10 Volume 41 May 16, 2003

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

<strong>2003</strong>0032957 Silesian Technical Univ., Gliwice<br />

A New Approach to the P-Wave Detection and Classification Based Upon Application of Wavelet Neural Network<br />

Domider, T.; Tkacz, E. J.; Kostka, P.; Wrzesniowski, A.; Oct 2001; 4 pp.; In English<br />

Report No.(s): AD-A4<strong>10</strong>247; No Copyright; Avail: CASI; A01, Hardcopy<br />

Paper presents a new approach to P wave classification problem which is based upon the application of a new recently<br />

develop and widely described tool such as Wavelet Neural Network, The novel idea of classification is based on creation of<br />

own non-standard wavelet exactly as a P wave morphology template and then calculation of wavelet transform being a first<br />

layer of classical multi-layer perceptron. The mentioned first layer works as a feature selector and extractor.<br />

DTIC<br />

Neural Nets; Wavelet Analysis; Electrocardiography<br />

<strong>2003</strong>0032986 Sophia Univ., Tokyo<br />

Reconstruction of Bio-Conductivity Distribution from Tangential Magnet Field Measurements<br />

Sumi, C.; Nagumo, K.; Oct 2001; 7 pp.; In English<br />

Report No.(s): AD-A4<strong>10</strong>5<strong>10</strong>; No Copyright; Avail: CASI; A02, Hardcopy<br />

We proposed a technique for reconstructing bio-electric conductivity distribution from measured tangential magnet field<br />

data. That is, in the 2D ROI with an arbitrary depth two orthogonal tangential components of 3D current vector field were<br />

respectively estimated from the synthetically measured two tangential magnetic fields, from which the 2D conductivity<br />

distribution was estimated. To cope with inevitable measurement errors, a robust numerical solution was developed, in which<br />

the modification method and the regularization method were efficiently utilized. By performing this 2D reconstruction at each<br />

depth, 3D conductivity distribution could be estimated. As typical applications, pathological state and/or bio-electric<br />

conductive path can be evaluated by monitoring the temporal change of the reconstructed 3D conductivity distribution. The<br />

feasibility of this technique was briefly verified by reconstructing a conductivity distribution using simulated noise-filled<br />

magnetic field data, with resultant reconstruction indicating that the approach could provide a practical means for robustly<br />

reconstructing a conductivity distribution.<br />

DTIC<br />

Bioelectricity; Magnetic Fields; Electrical Resistivity; Numerical Analysis; Estimating<br />

<strong>2003</strong>0033<strong>10</strong>1 Aristotle Univ. of Thessaloniki, Greece<br />

Alignment of Serially Acquired Slices Using a Global Energy Function<br />

Krinidis, Stelio; Nikou, Christophoros; Pitas, Ioannis; October 25, 2001; 5 pp.; In English<br />

Report No.(s): AD-A4<strong>10</strong>239; No Copyright; Avail: CASI; A01, Hardcopy<br />

An accurate, computationally efficient and fully-automated algorithm for the alignment of 2D serially acquired sections<br />

forming a 3D volume is presented. The method accounts for the main shortcomings of 3D image alignment: corrupted data<br />

(cuts and tears), dissimilarities or discontinuities between slices, non parallel or missing slices. The approach relies on the<br />

optimization of a global energy function, based on the object shape, measuring the similarity between a slice and its<br />

neighborhood in the 3D volume. Slice similarity is computed using the distance transform measure in both directions. No<br />

particular direction is privileged in the method avoiding global offsets, biases in the estimation and error propagation. The<br />

method was evaluated on real images (medical and biological 3D data) and the experimental results demonstrated the<br />

method’s accuracy as reconstruction errors are less than 1 degree in rotation and less than 1 pixel in translation.<br />

DTIC<br />

Algorithms; Alignment; Autonomy; Numerical Analysis; Optimization<br />

<strong>2003</strong>0033866 Inha Univ., Inchon, Korea, Republic of<br />

A Speckle Reduction Filter Using Wavelet-Based Methods for Medical Imaging Application<br />

Kang, Su Cheol; Hong, Seung Hong; October 25, 2001; 5 pp.; In English<br />

Report No.(s): AD-A4<strong>10</strong>299; No Copyright; Avail: CASI; A01, Hardcopy<br />

One of the most significant features of diagnostic echocardiographic images is to reduce speckle noise and make better<br />

image quality. In this paper we proposed a simple and effective filter design for image denoising and contrast enhancement<br />

based on multiscale wavelet denoising method. Wavelet threshold algorithms replace wavelet coefficients with small<br />

magnitude by zero and keep or shrink the other coefficients. This is basically a local procedure since wavelet coefficients<br />

characterize the local regularity of a function. After we estimate distribution of noise within echocardiographic image then<br />

apply to fitness Wavelet threshold algorithm. A common way of the estimating the speckle noise level in coherent imaging<br />

175

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!