检索结果-内蒙古大学图书馆

Virtual Dissection and Automated Polyp Detection of the Colon Based on Spiral CT – Techniques and Preliminary Experience on a Cadaveric PhantomVirtuelle Dissektion and automatische Detektion von Kolonpolypen basierend auf Spiral-CT-Daten – Technik und vorläufige Erfahrungen mit einem Leichenphantom

引用

European Surgery 2002年第2期34卷 143-149页

作者： E. Sorantin G. Werkgartner Emese Balogh Anna Vilanova i Bartrolí K. Palágyi L. G. Nyúl L. Ruskó From the 1Department of Radiology and the 2Department of Surgery University of Graz the 3Department of Applied Informatics University Szeged Hungary and the 4Institute of Computer Graphics and Algorithms University of Technology Vienna

Summary: Background : CT colonography was found to be sensitive and specific for detection of colonic polyps and colorectal cancer (CRC). Depending on the software used, CT colonography requires a certain amount of operator interaction, which limits it's widespread usage. The goal of this papers is to present two novel automated techniques for displaying CT colonography: virtual dissection and automated colonic polyp detection. Methods : Virtual dissection refers to a technique where the entire colon is virtually stretched and flattened thus simulating the view on the pathologist's table. Colonic folds show a ‘global outward bulging of the contour’, whereas colonic polyps exhibit the inverse (‘local inward bulging’). This feature is used to map areas of ‘local inward bulging’ with colours on 3D reconstructions. A cadaveric phantom with 13 artificially inserted polyps was used for validation of both techniques. Results : On virtual dissection all 13 inserted polyps could be identified. They appeared either as bumps or as local broadening of colonic folds. In addition, the automated colonic polyp detection algorithm was able to tag all polyps. Only 10 min of operator interaction were necessary for both techniques. Conclusions : Virtual dissection overcomes the shortcomings of CT colonography, and automated colonic polyp detection establishes a roadmap of the polyps. Zusammenfassung: Grundlagen : Die CT-Kolographie ermöglicht die Detektion von Kolonpolypen und kolorektalen Karzinomen. In Abhängigkeit von der verwendeten Software ist ein unterschiedlich großer Zeitaufwand notwendig, der die breite klinische Anwendung limitiert. Zweck der vorliegenden Arbeit ist die Präsentation zweier neuer Darstellungsverfahren für die CT-Kolographie: virtuelle Dissektion und automatische Detektion von Dickdarmpolypen. Methodik : Die virtuelle Dissektion ist eine Technik, bei der das gesamte Kolon aus den Spiral-CT-Daten extrahiert, artifiziell gestreckt, in seiner Längsrichtung aufge

关键词： Colonoscopy tomography colonic polyps colorectal neoplasms computer applications Virtuelle Kolonoskopie Kolonpolypen kolorektale Karzinome computerapplikationen

来源：评论

学校读者我要写书评

暂无评论

A QUANTITATIVE-COMPARATIVE APPROACH TO ANALYSIS OF DISTORTION IN MENTAL MAPS

引用

PROFESSIONAL GEOGRAPHER 1984年第3期36卷 326-337页

作者： WATERMAN, S GORDON, D STANLEY WATERMAN (Ph.D. in Geography University of Dublin 1969) is Senior Lecturer in Geography at the University of Haifa Haifa 31999 Israel. He has research interests in political and social geography. DAN GORDON (D.Sc. in Mathematics Technion—Israel Institute of Technology—1976) is Lecturer in Computer Studies at the University of Haifa. His research interests include design and analysis of algorithms VLSI computational geometry and computer graphics.

A quantitative procedure for analyzing and comparing distortion in mental maps is presented. Using a microcomputer and digitizer, and by developing a distortion index, comparisons are made by direct analysis of mental maps. A case study of the mental maps of Israel of high school and university students showed a tendency to generalize shape to simple geometric forms, with foreshortening of north-south lines and exaggeration of east-west distances.

关键词： mental maps distortion quantitative analysis comparison

来源：评论

学校读者我要写书评

暂无评论

Visualization of Biomolecular Structures: State of the Art 17

Visualization of Biomolecular Structures: State of the Art

引用

17th Eurographics Conference on Visualization - State of the Art Reports, EuroVis-STAR 2015

作者： Kozlíková, B. Krone, M. Lindow, N. Falk, M. Baaden, M. Baum, D. Viola, I. Parulek, J. Hege, H.-C. Faculty of Informatics Masaryk University Czech Republic Visualization Research Center University of Stuttgart Germany Department of Visual Data Analysis Zuse Institute Berlin Germany Immersive Visualization Group Linköping University Sweden Laboratoire de Biochimie Théorique UPR 9080 CNRS France Department of Informatics University of Bergen Norway Institute of Computer Graphics and Algorithms Vienna University of Technology Austria

ISBN: (纸本)9783905674996

Structural properties of molecules are of primary concern in many fields. This report provides a comprehensive overview on techniques that have been developed in the fields of molecular graphics and visualization with a focus on applications in structural biology. The field heavily relies on computerized geometric and visual representations of three-dimensional, complex, large, and time-varying molecular structures. The report presents a taxonomy that demonstrates which areas of molecular visualization have already been extensively investigated and where the field is currently heading. It discusses visualizations for molecular structures, strategies for efficient display regarding image quality and frame rate, covers different aspects of level of detail, and reviews visualizations illustrating the dynamic aspects of molecular simulation data. The report concludes with an outlook on promising and important research topics to enable further success in advancing the knowledge about interaction of molecular structures. © The Eurographics Association 2015.

关键词： Visualization

来源：评论

学校读者我要写书评

暂无评论

Exploit fully automatic low-level segmented PET data for training high-level deep learning algorithms for the corresponding CT data

arXiv

引用

arXiv 2019年

作者： Gsaxner, Christina Roth, Peter M. Wallner, Jürgen Egger, Jan Institute for Computer Graphics and Vision Faculty of Computer Science and Biomedical Engineering Graz University of Technology Graz Austria Computer Algorithms for Medicine Laboratory Graz Austria Department of Oral & Maxillofacial Surgery Medical University of Graz Auenbruggerplatz Styria Austria

We present an approach for fully automatic urinary bladder segmentation in CT images with artificial neural networks in this study. Automatic medical image analysis has become an invaluable tool in the different treatment stages of diseases. Especially medical image segmentation plays a vital role, since segmentation is often the initial step in an image analysis pipeline. Since deep neural networks have made a large impact on the field of image processing in the past years, we use two different deep learning architectures to segment the urinary bladder. Both of these architectures are based on pre-trained classification networks that are adapted to perform semantic segmentation. Since deep neural networks require a large amount of training data, specifically images and corresponding ground truth labels, we furthermore propose a method to generate such a suitable training data set from Positron Emission Tomography/Computed Tomography image data. This is done by applying thresholding to the Positron Emission Tomography data for obtaining a ground truth and by utilizing data augmentation to enlarge the dataset. In this study, we discuss the influence of data augmentation on the segmentation results, and compare and evaluate the proposed architectures in terms of qualitative and quantitative segmentation performance. The results presented in this study allow concluding that deep neural networks can be considered a promising approach to segment the urinary bladder in CT images. Copyright © 2019, The Authors. All rights reserved.

关键词： Deep neural networks

来源：评论

学校读者我要写书评

暂无评论

Simulated Reality in Automotive Design

Simulated Reality in Automotive Design

引用

International Conference on Cyberworlds

作者： Andre Stork Clemens-August Thole Stanislav Klimenko Igor Nikitin Lialia Nikitina Yuri Astakhov IGD Fraunhofer Institute of Computer Graphics Research (IGD) Darmstadt Germany SCAI Fraunhofer Institute for Algorithms and Scientific Computing Darmstadt Germany ICPT Institute of Computing for Physics and Technology Moscow Russia Mathematical Institute University of Cologne Germany

In this paper we introduce Simulated Reality (SR) as a new concept for the interplay between simulation, optimization and interactive visualization. We see SR as a new metaphor for the interactive visual exploration of simulation and optimization results. The vision of Simulated Reality implies interactive behavior of simulations. Fact is today that simulations might still need hours of computation time, especially in crash worthiness. This paper shows approaches to come closer to the vision of SR. Combining design of experiments methods, metamodeling, new interpolation schemes and innovative graphics methods, we enable to user to interact with simulation parameters, optimization criteria and come to a new interpolated crash result within seconds. The approaches have been successfully applied for solution of real life car design optimization problems.

关键词： Automotive engineering Computational modeling Strontium Design optimization Visualization computer crashes Design methodology Metamodeling Interpolation graphics

来源：评论

学校读者我要写书评

暂无评论

Needle-stability maps for brain-tumor biopsies

Needle-stability maps for brain-tumor biopsies

引用

International Conference on System Theory, Control, and Computing (ICSTCC)

作者： Paul Herghelegiu Vasile Manta Eduard Gröller Faculty of Automatic Control and Computer Engineering Technical University “Gheorghe Asachi” Iasi Iasi Romania Vienna University of Technology Institute of Computer Graphics and Algorithms Favoritenstr. 9/5. Stock A-1040 Austria

Minimally invasive surgical procedures like biopsies require the insertion of a needle to reach a specific tissue from where samples are taken. This process is affected by a number of errors that can lead to a different needle pathway than originally planned. In the case of brain-tumor biopsies, these errors can be caused by the brain shifting when the skull is drilled, measurement errors due to the physical framework that supports the biopsy needle or some other human errors. To provide support for preoperative planning, we introduce the concept of a biopsy-needle stability-map. This map provides information on how stable a biopsy-needle pathway is. We also introduce an algorithm for finding the reachable points on the tumor border from one specific entry point. A technique for automatically selecting the needle pathway that offers the biggest minimal distance to any blood vessel is also presented. A 3D representation of the regions of interest (tumor, blood vessels) together with the needle pathway and the reachable points of the tumor has also been implemented. The resulting stability map visually represents, using color-coding, how close to any blood vessel the pathways surrounding the main one are.

关键词： Needles Tumors Blood vessels Biomedical imaging Stability analysis Image segmentation Transforms

来源：评论

学校读者我要写书评

暂无评论

Profile Flags: a novel metaphor for probing of T/sub 2/ maps

Profile Flags: a novel metaphor for probing of T/sub 2/ maps

引用

IEEE Conference on Visualization

作者： M. Mlejnek P. Ermest A. Vilanova R. van der Rijt H. van den Bosch F. Gerritsen M.E. Groller Institute of Computer Graphics and Algorithms University of Technology Vienna Austria Deorlrtment of Biomedical Engineering Technische Universiteit Eindhoven Netherlands Catharina Hospital Eindhovn Netherlands Philips Medical Systems Best Netherlands

This paper describes a tool for the visualization of T/sub 2/ maps of knee cartilage. Given the anatomical scan, and the T/sub 2/ map of the cartilage, we combine the information on the shape and the quality of the cartilage in a single image. The Profile Flag is an intuitive 3D glyph for probing and annotating of the underlying data. It comprises a bulletin board pin-like shape with a small flag on top of it. While moving the glyph along the reconstructed surface of an object, the curve data measured along the pin's needle and in its neighborhood are shown on the flag. The application area of the Profile Flag is manifold, enabling the visualization of profile data of dense but in-homogeneous objects. Furthermore, it extracts the essential part of the data without removing or even reducing the context information. By sticking Profile Flags into the investigated structure, one or more significant locations can be annotated by showing the local characteristics of the data at that locations. In this paper we are demonstrating the properties of the tool by visualizing T/sub 2/ maps of knee cartilage.

关键词： Bones Shape Image reconstruction Lesions Surface reconstruction Switches Visualization USA Councils Osteoarthritis Medical treatment

来源：评论

学校读者我要写书评

暂无评论

Hybrid Metaheuristics 1

引用

丛书名： Lecture Notes in computer Science

1000年

作者： María J. Blesa Christian Blum Günther Raidl Andrea Roli Michael Sampels

来源：评论

学校读者我要写书评

暂无评论

Parallel vectors criteria for unsteady flow vertices

Parallel vectors criteria for unsteady flow vertices

引用

作者： Fuchs, Raphael Peikert, Ronald Hauser, Helwig Sadlo, Filip Muigg, Philipp IEEE Institute of Computer Graphics and Algorithms Vienna University of Technology Favoritenstrasse 9-11/E186 A-1040 Wien Austria Institute of Computational Science ETH Zentrum IFW C27.2 Haldeneggsteig 4 CH-8092 Zürich Switzerland Department of Informatics University of Bergen Postboks 7803 N-5020 Bergen Norway VRVis Research Center TechGate Vienna Donau-City-Strasse 1 A-1220 Wien Austria

Feature-based flow visualization is naturally dependent on feature extraction. To extract flow features, often higher-order properties of the flow data are used such as the Jacobian or curvature properties, implicitly describing the flow features in terms of their inherent flow characteristics (e.g., collinear flow and vorticity vectors). In this paper we present recent research which leads to the (not really surprising) conclusion that feature extraction algorithms need to be extended to a time-dependent analysis framework (in terms of time derivatives) when dealing with unsteady flow data. Accordingly, we present two extensions of the parallel vectors based vortex extraction criteria to the time-dependent domain and show the improvements of feature-based flow visualization in comparison to the steady versions of this extraction algorithm both in the context of a high-resolution dataset, i.e., a simulation specifically designed to evaluate our new approach, as well as for a real-world dataset from a concrete application. © 2006 IEEE.

关键词： Flow visualization

来源：评论

学校读者我要写书评

暂无评论

TimeTubes: Visual Exploration of Observed Blazar Datasets

TimeTubes: Visual Exploration of Observed Blazar Datasets

引用

International Meeting on High-Dimensional Data-Driven Science, HD3 2017

作者： Fujishiro, Issei Sawada, Naoko Nakayama, Masanori Wu, Hsiang-Yun Watanabe, Kazuho Takahashi, Shigeo Uemura, Makoto Center for Information and Computer Science Keio University 3-14-1 Hiyoshi Kohoku-ku Yokohama223-8522 Japan Institute of Computer Graphics and Algorithms TU Wien Favoritenstr. 9 / 5. Stock ViennaA-1040 Austria Department of Computer Science and Engineering Toyohashi University of Technology 1-1 Hibarigaoka Tempaku-cho Toyohashi441-8580 Japan School of Computer Science and Engineering University of Aizu Aizu Wakamatsu Fukushima965-8580 Japan Astrophysical Science Center Hiroshima University 1-3-1 Kagamiyama Higashi-Hiroshima739-8526 Japan

Blazars are attractive objects for astronomers to observe in order to burrow into the magnetic field in the relativistic jet. This paper presents TimeTubes as a novel visualization scheme that allows astronomers to interactively explore characteristic temporal variation patterns in observed blazar datasets. In the TimeTubes spatialization, the two Stokes parameters and their errors with a common timestamp are transformed into an ellipse. A series of such ellipses are aligned in parallel along the timeline to form a 3D volumetric tube. The resulting tube is then colorized by the observed intensities and colors of the blazar, and finally volume-rendered. A designated user interface is provided with visual exploration functions according to Shneiderman's Visual Information Seeking Mantra. In the latest version, an auxiliary mechanism, called visual data fusion, was incorporated to ameliorate data- and mapping-inherent uncertainties for more efficient and effective visual exploration. © Published under licence by IOP Publishing Ltd.

关键词： Data fusion

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：