Die vorliegende Arbeit gibt über die Bedeutung der Tourismusindustrie in der heutigen Zeit Aufschluss. Im Laufe der Arbeit wird der Einfluss des Tourismus auf ausgewählte Aspekte der Wirtschaft dargestellt und untersucht. Außerdem erfolgt eine Analyse und Untersuchung dieses Einflusses an einem konkreten Beispiel, der Türkei

A.M. McIntosh

A.R. Hariri

D.O. Siegmund

J.K. Haseman

L. Almasy

M. Jenkinson

M.-C. Chiang

M.C. Chiang

N.K. Hansell

P.M. Thompson

S.M. Smith

W.H. Press

Y. Benjamini

An innovative 3D multi-branch tubular structure and centerline extraction method is proposed in this paper. In contrast to classical minimal path techniques that can only detect a single curve between two pre-defined initial points, this method propagates outward from only one initial seed point to detect 3D multi-branch tubular surfaces and centerlines simultaneously. First, instead of only representing the trajectory of a tubular structure as a 3D curve, the surface of the entire structure is represented as a 4D curve along which every point represents a 3D sphere inside the tubular structure. Then, from any given sphere inside the tubular structure, a novel 4D iterative key point searching scheme is applied, in which the minimal action map and the Euclidean length map are calculated with a 4D freezing fast marching evolution. A set of 4D key points is obtained during the front propagation process. Finally, by sliding back from each key point to the previous one via the minimal action map until all the key points are visited, we are able to fully obtain global minimizing multi-branch tubular surfaces. An additional immediate benefit of this method is a natural notion of a multi-branch tube’s “central curve” by taking only the first three spatial coordinates of the detected 4D multi-branch curve. Experimental results on 2D/3D medical vascular images illustrate the benefits of this method.ou

Cohen, Laurent D.

Yezzi, Anthony

Li, Hua

Base de publications de l'université Paris-Dauphine

3D Multi-branch Tubular Surface and Centerline Extraction with 4D Iterative Key Points

International audienceGraph Cuts have been shown as a powerful interactive segmentation technique in several medical domains.We propose to automate the Graph Cuts in order to automatically segment Multiple Sclerosis (MS) lesions in MRI. We replace the manual interaction with a robust EM-based approach in order to discriminate between MS lesions and the Normal Appearing Brain Tissues (NABT). Evaluation is performed in synthetic and real images showing good agreement between the automatic segmentation and the target segmentation. We compare our algorithm with the state of the art techniques and with several manual segmentations. An advantage of our algorithm over previously published ones is the possibility to semi-automatically improve the segmentation due to the Graph Cuts interactive feature

García-Lorenzo, Daniel

Lecoeur, Jérémy

Arnold, Douglas,

Collins, D. Louis

Barillot, Christian

HAL Descartes

Multiple Sclerosis lesion segmentation using an automatic multimodal Graph Cuts: Multiple Sclerosis lesion segmentation using an automatic multimodal Graph Cuts

Arnold, Douglas, L.

HAL-Rennes 1

HAL-Inserm

A. Frangi

J. Duncan

C. Kirbas

Y. Sato

L. Lorigo

S. Aylward

O. Wink

A. Chung

S. Bouix

P. Yan

T. Deschamps

J. Sethian

H. Li

L. Cohen

Crossref

INRIA a CCSD electronic archive server

Abstract. An innovative 3D multi-branch tubular structure and centerline ex-traction method is proposed in this paper. In contrast to classical minimal path techniques that can only detect a single curve between two pre-defined initial points, this method propagates outward from only one initial seed point to detect 3D multi-branch tubular surfaces and centerlines simultaneously. First, instead of only representing the trajectory of a tubular structure as a 3D curve, the surface of the entire structure is represented as a 4D curve along which every point repre-sents a 3D sphere inside the tubular structure. Then, from any given sphere inside the tubular structure, a novel 4D iterative key point searching scheme is applied, in which the minimal action map and the Euclidean length map are calculated with a 4D freezing fast marching evolution. A set of 4D key points is obtained during the front propagation process. Finally, by sliding back from each key point to the previous one via the minimal action map until all the key points are visited, we are able to fully obtain global minimizing multi-branch tubular surfaces. An additional immediate benefit of this method is a natural notion of a multi-branch tube’s “central curve ” by taking only the first three spatial coordinates of the de-tected 4D multi-branch curve. Experimental results on 2D/3D medical vascular images illustrate the benefits of this method. 

Hua Li

Anthony Yezzi

Laurent Cohen

CiteSeerX

3D multi-branch tubular surface and centerline extraction with 4D iterative key points