检索结果-内蒙古大学图书馆

作者： Shakya, Kabita Deegan, Catherine Hegarty, Fran Markham, Charles Sch. of Informatics and Engineering Inst. of Technology Blanchardstown Dublin 2 Ireland Dept. of Med. Phys. and Bioeng. St. James's Hospital Dublin 2 Ireland Department of Computer Science National University of Ireland Maynooth Ireland

This paper presents a new technique to determine the dynamic and frequency response of capnographs using a custom built 'EtCO2 simulator system'. Capnographs are devices that use CO2 from a patients' expired breath to monitor the cardiopulmonary status during anaesthesia and mechanical ventilation. Capnographs at present are routinely calibrated via a static calibration method only. The dynamic response of the capnographs is not accounted for. The frequency and time response are important as they determine if capnographs can be used in high frequency and pediatric ventilation schemes. Experiments performed using the method described in this paper proved that old capnographs usually do not satisfy the manufacturer quoted specifications for time and frequency response. Therefore, a routine check for capnographs is recommended. The method can also be used to verify manufacturer quoted specifications. The EtCO2 simulator system, designed and constructed simulates human respiration cycle. The gas sources used are 5% CO2 and room air that can be switched alternatively. Both supplies are pressure regulated and connected through non-return valves to electric valves. The valves are microprocessor controlled and the on/off time is user defined allowing a wide range of waveforms to be simulated. The output from the simulator is delivered to capnograph. Capnograms are captured by digital video recording. The captured video in 'avi' file format is then converted into individual frames. These frames are converted into digital data through image processing in Matlab. The data obtained is subjected to extensive analysis to determine the frequency and time response of the respective capnograph. Copyright 2005 ISA. All Rights Reserved.

关键词： biomedical equipment

来源：评论

学校读者我要写书评

暂无评论

The software interface to the 3D-force microscope

The software interface to the 3D-force microscope

引用

IEEE Conference on Visualization

作者： D. Marshburn C. Weigle B.G. Wilde R.M. Taylor K. Desai J.K. Fisher J. Cribb E.T. O'Brien R. Superfine Department of Computer Science North Carolina State University Chapel Hill USA Dept. of Computer Science University of North Carolina at Chapel Hill Department of Biomedical Engineering North Carolina State University Chapel Hill USA Dept. of Biomedical Engineering University of North Carolina at Chapel Hill Dept. of Physics and Astronomy University of North Carolina at Chapel Hill Department of Physics and Astronomy North Carolina State University Chapel Hill USA

We have developed a real-time experiment-control and data-display system for a novel microscope, the 3D-force microscope (3DFM), which is designed for nanometer-scale and nanoNewton-force biophysical experiments. The 3DFM software suite synthesizes the several data sources from the 3DFM into a coherent view and provides control over data collection and specimen manipulation. Herein, we describe the system architecture designed to handle the several feedback loops and data flows present in the microscope and its control system. We describe the visualization techniques used in the 3DFM software suite, where used, and on which types of data. We present feedback from our scientist-users regarding the usefulness of these techniques, and we also present lessons learned from our successive implementations.

关键词： Magnetic flux Atomic force microscopy Visualization Magnetic force microscopy Hardware Probes Physics Real time systems Control systems computer graphics

来源：评论

学校读者我要写书评

暂无评论

An application of MAP-MRF to change detection in image sequence based on mean field theory

An application of MAP-MRF to change detection in image seque...

引用

作者： Liu, Qiang Sclabassi, Robert J. Li, Ching-Chung Sun, Mingui Laboratory for Computational Neuroscience Departments of Neurological Surgery and Electrical Engineering University of Pittsburgh Pittsburgh PA 15213 United States University of Pittsburgh Pittsburgh United States Dept. of Neurol. Surg. Elec. Eng. Neurosci. Mech. Eng. Psychiatry and Biomedical Engineering University of Pittsburgh Department of Electrical Engineering and Computer Science University of Pittsburgh Pittsburgh PA Center for Clinical Neurophysiology Department of Neurological Surgery University of Pittsburgh Research at Computational Diagnostics Inc.

Change detection is one of the most important problems in video segmentation. In conventional methods, predetermined thresholds are utilized to test the variation between frames. Although certain reasonings about the thresholds are provided, appropriate determination of these parameters is still problematic. We present a new approach to change detection from an optimization point of view. We model the video frames and the change detection map (CDM) as Markov random fields (MRFs), and formulate change detection into a problem of seeking the optimal configuration of the CDM. Under the MRP assumption, the optimal solution, in the sense of maximum a posteriori (MAP), is obtained by minimizing the energy function associated with the MRF which is designed by utilizing the prior knowledge of noise and contextual constraints on the video frames. An algorithm that computes the potentials and optimizes the solution is constructed by applying the mean field theory (MFT). The experimental results show that the new method detects changes accurately and is robust to noise. © 2005 Hindawi Publishing Corporation.

关键词： Image segmentation

来源：评论

学校读者我要写书评

暂无评论

Data-image-video encryption

引用

IEEE Potentials 2004年第3期23卷 28-34页

作者： Yang, Ming Bourbakis, Nikolaos Li, Shujun Department of Computer Science and Engineering Wright State University Dayton OH United States Department of Informatics Wright State University Dayton OH United States IEEE EIC IJAIT Portugal Dept. of Electronic Engineering City University of Hong Kong Kowloon Toon Hong Kong

No abstract available

关键词： Cryptography Digital images Data security Protection Public key Image coding Image analysis Algorithm design and analysis Video compression Computational efficiency

来源：评论

学校读者我要写书评

暂无评论

The Healthgrid White Paper 3

The Healthgrid White Paper

引用

3rd Annual Conference of the Healthgrid Association, Healthgrid 2005

作者： Breton, Vincent Dean, Kevin Solomonides, Tony Aloisio, Giovanni Benkner, Siegfried Bilofsky, Howard Blanquer, Ignacio Brady, Michael Cannataro, Mario Chouvarda, Ioanna Claerhout, Brecht De Moor, Georges De Neve, Wilfried De Wagter, Carlos Fiore, Sandro Hassan, Kinda Heeren, Germaine Hernández, Vicente Herveg, Jean A.M. Hofmann, Martin Jones, Chris Koutkias, Vassilios Lloyd, Sharon Lonsdale, Guy Alonso, Victoria L. Maglaveras, Nicos Maigne, Lydia Malousi, Andigoni Martín-Sánchez, Fernando McClatchey, Richard Medico, Enzo Miguet, Serge Mirto, Maria Montagnat, Johan Nørager1, Sofie Nozaki, Kazunori Oliveira, Ilídio Castro Pennec, Xavier Poullet, Yves Merino, Juan Pedro Sánchez Strizh, Irina G. Taillet, Michel Tristram, Clive Tverdokhlebov, Nikolay Veltri, Pierangelo Ziegler, René CNRS-IN2P3 LPC Campus des Cézeaux AubiereCedex63177 France Internet Business Solutions Group Cisco Systems 9 New Square Bedfont Lakes Middlesex FelthamTW14 8HA United Kingdom University of the West of England Bristol CEMS Coldharbour Lane BristolBS6 6TH United Kingdom Center for Advanced Computational Technologies ISUFI Dept. of Innovation Engineering University of Lecce Via per Monteroni Lecce73100 Italy Institute of Scientific Computing University of Vienna Nordbergstrasse 15 ViennaA-1090 Austria University of Pennsylvania School of Engineering and Applied Science Computer and Information Science Center for Bioinformatics 1416 Blockley Hall 423 Guardian Drive PhiladelphiaPA19104-6021 United States Universidad Politecnica de Valencia Camino de Vera/n Valencia46022 Spain FRS FREng Dept. of Engineering Science Oxford University Parks Road OxfordOX1 3PJ United Kingdom Magna Graecia University of Catanzaro School of Bioinformatics and Biomedical Engineering Campus di Germaneto Viale Europa Germaneto Catanzaro88100 Italy Aristotle University The Medical School Lab of Medical Informatics Box 323 Thessaloniki54124 Greece Custodix NV Verlorenbroodstraat 120 Bus 14 MerelbekeB-9820 Belgium Research in Advanced Medical Informatics and Telematics UZ Gent 5K3 De Pintelaan 185 GentB9000 Belgium Department of Radiotherapy Ghent University Hospital Building P7 De Pintelaan 185 GentB-9000 Belgium Laboratoire LIRIS Université Lumière Lyon 2 Campus Porte des Alpes 5 avenue Pierre Mendès France Bron69676 France av. E.Mounierlaan 83 Brussels1200 Belgium Faculté de Droit de Namur - FUNDP Centre de Recherches Informatiques & Droit 5 rempart de la Vierge Namur5000 Belgium Schloss Birlinghoven Sankt Augustin53754 Germany CERN Geneva 231211 Switzerland Oxford University Computing Laboratory Wolfson Building OxfordOX1 3QD United Kingdom C&C Research Laboratories NEC Europe Ltd. Rathausallee 10 Sankt AugustinD-53757 Germany Medic

ISBN: (纸本)158603510X

Over the last four years, a community of researchers working on Grid and High Performance Computing technologies started discussing the barriers and opportunities that grid technologies must face and exploit for the development of health-related applications. This interest lead to the first Healthgrid conference, held in Lyon, France, on January 16th–17th, 2003, with the focus of creating increased awareness about the possibilities and advantages linked to the deployment of grid technologies in health, ultimately targeting the creation of a European/international grid infrastructure for health. The topics of this conference converged with the position of the eHealth division of the European Commission, whose mandate from the Lisbon Meeting was "To develop an intelligent environment that enables ubiquitous management of citizens’ health status, and to assist health professionals in coping with some major challenges, risk management and the integration into clinical practice of advances in health knowledge." In this context "Health" involves not only clinical procedures but covers the whole range of information from molecular level (genetic and proteomic information) over cells and tissues, to the individual and finally the population level (social healthcare). Grid technology offers the opportunity to create a common working backbone for all different members of this large "health family" and will hopefully lead to an increased awareness and interoperability among disciplines. The first HealthGrid conference led to the creation of the Healthgrid association, a non-profit research association legally incorporated in France but formed from the broad community of European researchers and institutions sharing expertise in health grids. After the second Healthgrid conference, held in Clermont-Ferrand on January 29th–30th, 2004, the need for a "white paper" on the current status and prospective of health grids was raised. Over fifty experts from different areas of grid tec

关键词： Health risks

来源：评论

学校读者我要写书评

暂无评论

An algorithm for EMG noise detection in large ECG data

An algorithm for EMG noise detection in large ECG data

引用

computers in Cardiology 2004

作者： Raphisak, P. Schuckers, S.C. De Jongh Curry, A. Lane Department of Computer Science and Electrical Engineering West Virginia University United States Department of Electrical and Computer Engineering Clarkson University United States Department of Biomedical Engineering University of Memphis United States Dept. of Electrical and Computer Eng. Clarkson University P.O. Box 5720 Postdam NY 13699 United States

Large collections of electrocardiogram recordings (ECG) are valuable for researchers. However, some sections of the recorded ECG may be corrupted by electromyogram (EMG) noise from muscle. Therefore, EMG noise needs to be detected and filtered before performing data processing. In this study, an automated algorithm for detecting EMG noise in large ECG data is presented. The algorithm extracts EMG artifact from the ECG by using a morphological filter. EMG is identified by setting a threshold for the moving variance of extracted EMG. The algorithm achieved 100% detection rate on the training data. The algorithm was tested on 150 test signals from three sets of test signals (50 signals in each set). Set 1 was created by adding EMG noise to EMG-free ECG signals, set 2 was manually selected ECG sections which contain EMG noise, and set 3 contained randomly selected ECG signals. Sensitivity was 100%, 94%, and 100% on sets 1, 2, and 3, respectively. All sets had 100% specificity. The algorithm has computational complexity of O(N). © 2004 IEEE.

关键词： Spurious signal noise

来源：评论

学校读者我要写书评

暂无评论

Power spectral density estimation and tracking of nonstationary pressure signals based on Kalman filtering

Power spectral density estimation and tracking of nonstation...

引用

Conference Proceedings - 26th Annual International Conference of the IEEE engineering in Medicine and Biology Society, EMBC 2004

作者： Aboy, M. McNames, J. Márquez, Óscar W. Hornero, R. Thong, T. Goldstein, B. Biomed. Signal Processing Laboratory Electrical and Computer Engineering Portland State University Portland United States Signal Theory Dept. ETSI-Telecomunicación University of Vigo Spain Signal Theory Dept. ETSI-Telecomunicación University of Valladolid Spain Biomedical Engineering Department Oregon Health and Science University Portland United States Pediatrics Department Oregon Health and Science University Portland United States

We describe an algorithm to estimate and track slow changes in power spectral density (PSD) of nonstationary pressure signals. The algorithm is based on a Kalman filter that adaptively generates an estimate of the autoregressive model parameters at each time instant. The algorithm exhibits superior PSD tracking performance in nonstationary pressure signals than classical nonparametric methodologies, and does not assume a piecewise stationary model of the data. Furthermore, it provides better time-frequency resolution, and is robust to model mismatches. We demonstrate its usefulness by a sample application involving PSD estimation and tracking of short records of simulated pressure waveforms. This algorithm is intended for applications were the PSD must be estimated and tacked during short transient periods, possibly after clinical interventions.

关键词： Signal processing

来源：评论

学校读者我要写书评

暂无评论

Motif extraction from weighted sequences

引用

11th International Conference on String Processing and Information Retrieval, SPIRE 2004

作者： Iliopoulos, Costas S. Perdikuri, Katerina Theodoridis, Evangelos Tsakalidis, Athanasios Tsichlas, Kostas Department of Computer Science King’s College London LondonWC2R 2LS United Kingdom Computer Engineering and Informatics Dept. Of University of Patras Patras26500 Greece 61 Riga Feraiou St Patras26221 Greece

ISBN: (纸本)9783540232100

We present in this paper three algorithms. The first extracts repeated motifs from a weighted sequence. The motifs correspond to words which occur at least q times and with hamming distance e in a weighted sequence with probability ≥ 1/k each time, where k is a small constant. The second algorithm extracts common motifs from a set of N ≥ 2 weighted sequences with hamming distance e. In the second case, the motifs must occur twice with probability ≥ 1/k, in 1 ≤ q ≤ N distinct sequences of the set. The third algorithm extracts maximal pairs from a weighted sequence. A pair in a sequence is the occurrence of the same substring twice. In addition, the algorithms presented in this paper improve slightly on previous work on these problems. © Springer-Verlag Berlin Heidelberg 2004.

关键词： Hamming distance

来源：评论

学校读者我要写书评

暂无评论

Motion artifact reduction in MRI through generalized DFT

Motion artifact reduction in MRI through generalized DFT

引用

IEEE International Symposium on biomedical Imaging

作者： H. Knutsson M. Andersson L. Wigstrom M. Borga A. Sigfridsson Center for Medical Image Science and Visualization Linköping University Sweden Linkopings universitet Linkoping SE Dept. of Biomedical Eng. Linkoping Univ. Sweden Medical Informatics Department of Biomedical Engineering Linköping University Sweden

This paper presents a method that dramatically reduces artifacts caused by respiratory (and similar types of) patient motion in magnetic resonance imaging (MRI). The basis for the method is the observation that affine deformations of an object will correspond to a different but unique affine coordinate transform (plus phase shift) of the Fourier representation of the object. The resulting sample points will be irregularly distributed prohibiting the use of standard IFFT to reconstruct the object. The object can however be reconstructed through the use of a weighted regularized pseudo inverse. A standard pseudo inverse is, however, not possible due to excessive computational demands. For this reason a novel fast sequential pseudo inverse algorithm is also presented. Significantly improved results are obtained on both synthetic and clinical data.

关键词： Magnetic resonance imaging Fourier transforms Image reconstruction Image sampling Discrete Fourier transforms biomedical informatics biomedical engineering biomedical imaging Visualization Thorax

来源：评论

学校读者我要写书评

暂无评论

A genetic algorithm for inferring time delays in gene regulatory networks

A genetic algorithm for inferring time delays in gene regula...

引用

Proceedings of the IEEE Computational Systems Bioinformatics Conference, CSB

作者： Fang-Xiang Wu A.J. Kusalik Wen-Jun Zhang Department of Biomedical Engineering University of Saskatchewan Saskatoon SAS Canada Department of Computer Science University of Saskatchewan Saskatoon SAS Canada University of Saskatchewan Saskatoon SK CA Dept. of Biomedical Eng. Saskatchewan Univ. Saskatoon Sask. Canada

Recently we proposed a state-space model with time delays for gene regulatory networks. Although the system can be uniquely determined under some assumptions, the solution space is still too large to use an exhaustive search method to find the optimal solution. This work employs Boolean variables to capture the existence of the discrete time delays of the regulatory relationships among the internal variables, and proposes a genetic algorithm (GA) to determine the optimal Boolean variables (the optimal solution) and to further infer gene regulatory networks with time delays. Computational experiments performed on a real gene expression dataset show that GA is effective at finding the optimal solution. Not only does the regulatory network with time delay obtained from the dataset possesses the expected properties of a real one, but the approach also improves the prediction accuracy by 72%, compared to gene regulatory network without time delays.

关键词： Genetic algorithms Delay effects Intelligent networks Gene expression Search methods Equations Parameter estimation Accuracy Bayesian methods Information analysis

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：