Advancing Local Distance Discrimination of Explosions and Earthquakes with Joint P/S and M L ‐M C Classification

Abstract Funding Acknowledgements Dr Teres was funded by Swiss Heartrhythm Foundation Introduction pulmonary vein (PV) reconnections due to gaps on circumferential ablation lines are responsible for atrial fibrillation recurrences after catheter ablation. We sought to analyze the local left atrial wall thickness (LAWT) of PV line gaps at AF redo ablation during real-time catheter positioning. LAWT was measured on the MDCT 3D reconstruction and fused with the LA anatomy using CARTO-merge. Objective To analyze the relationship between local reconnection gaps and the LAWT during AF redo procedures. Methods Single-Center cohort study that included 41 consecutive patients referred for AF redo procedure. All patients had a MDCT prior to the ablation procedure. LAWT maps were semi-automatically computed from the MDCT as the local distance between the LA endo and epicardium. Each PV line was subdivided into 8 segments and mean LAWT was computed. During the procedure, the local gap was defined as the earliest activation site at the reconnected segment of the circumferential PV line (Figure 1A & 1B). Results 41 patients [31 (75.6%) male, age 60 ± 10 years] were included. Mean LAWT was 1.36 ± 0.20 mm. Mean PV circumferential line WT was higher in left PVs than in the right PVs 1.68 ± 0.57 vs. 1.31 ± 0.39 mm p < 0.001 respectively. Mean WT of the reconnected points was 44% higher than the mean WT of the segment where the reconnection was located. Mean reconnection point WT was at the 87th percentile of the circumferential line in the LPVs and at the 76th percentile in the RPVs. The reconnected point WT was higher in the LPVs than RPVs 2.13 ± 1.14 vs. 1.47 ± 0.48 mm p < 0.001 respectively. The most frequent location for reconnections was the left anterior carina (71%), with a mean WT of 2.24 ± 0.91mm; and the right anterior carina (56%) with a mean WT of 1.57 ± 0.62mm (Figure 2A & 2B). Conclusions Reconnection points were more frequently present in the thicker segments of the PV circumferential line. The most frequently reconnected segment was the anterior carina in both right and left PVs. Atrial wall thickness maps derived from MDCT are useful to guide AF redo procedures. Abstract Figure. 1) Activation & WT map; 2) Segment WT

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Improved Minimum Distance Discrimination Method Used in Image Analysis of Fabric Wear Resistance

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.263-266.421 ◽

2012 ◽

Vol 263-266 ◽

pp. 421-426 ◽

Cited By ~ 1

Author(s):

Jian Xia Su ◽

Run Ping Han ◽

Li Min Shi ◽

Xing He Qian

Keyword(s):

Image Processing ◽

Wear Resistance ◽

Minimum Distance ◽

Standard Sample ◽

Resistance Level ◽

Image Preprocessing ◽

Maximum Area ◽

Hair Bulb ◽

Distance Discrimination ◽

Discrimination Method

With the increasing attention of textile, the wear resistance of the fabric is more and more important today. The wear resistance is judged by the sample and standard sample according to sensory contrast complete, but this approach has repeated poor consistency. The subjective factors of testers influence the result heavily. So the powerful image processing tools of MATLAB was used in the analysis of fabrics image processing. By image read, display and interception, image preprocessing, and feature extraction value, the eigenvalues of total area of the hair bulb, maximum area of the hair bulb, and hair bulb number were obtained. After the improved minimum distance discrimination method was used to determine the level of wear resistance by computer. Tests show that fabrics wear resistance level can be judged quickly, accurately and automatically.

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