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Hybrid TOF-PET/MRI local transceiver coil

Physica Medica 2016年 32卷 232-232页

作者： Bartosz Głowacz D. Alfs T. Bednarski P. Białas E. Czerwiński A. Gajos M. Gorgol B. Jasińska D. Kamińska G. Korcyl P. Kowalski T. Kozik W. Krzemień E. Kubicz M. Mohammed M. Pawlik-Niedźwiecka S. Niedźwiecki M. Pałka L. Raczyński Z. Rudy P. Moskal Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University S. Łojasiewicza 11 30-348 Kraków Poland Department of Nuclear Methods Institute of Physics Maria Curie-Sklodowska University Pl. M. Curie-Sklodowskiej 1 20-031 Lublin Poland High Energy Physics Division National Centre for Nuclear Research A. Soltana 7 05-400 Otwock-Świerk Poland Świerk Computing Centre National Centre for Nuclear Research A. Soltana 7 05-400 Otwock-Świerk Poland

In order to enhance diagnostic capabilities Positron Emission Tomography (PET) and Magnetic Resonance Imaging (MRI) devices are combined into a single hybrid device providing an access to both metabolic and morphological information during a single examination. Typically the PET detectors are placed inside the diagnostic volume of the MRI scanner, however being outside the commonly used local transmit-receiver (transceiver) coils such as head or chest coils. Coils are made of plastic parts and metal conductors on which annihilation gamma quanta may scatter before reaching the PET detectors scintillating material. This fact could cause the worsening of PET images spatial resolution and the field-of-view for the PET detectors. We propose a solution based on a novel PET tomograph concept comprising multiple detection modules, built from polymer scintillation strip ended with silicon photodetectors, arranged circumferentially inside the working volume of the MRI local transceiver coil. The adaptive of the polymer scintillators in both shape and size properties allows for a use of a standard MRI coils constructions to be combined with PET detection system without influence on the coil shape, geometry and material properties optimized so far. Current work is focused on a dedicated detection electronics development based on silicon photodetectors arrays and digital signal processing unit that will operate in high static magnetic field as well as radiofrequency waves environment of MRI scanner. The novel approach to the hybrid local coil construction would allow for using any existing MRI system extending its functionality by the PET imaging feature. Disclosure Authors disclose any relationship that may bias the presentation.

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Operational data classes for establishing situational awareness in cyberspace 6

Operational data classes for establishing situational awaren...

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2014 6th International Conference on Cyber Conflict, CYCON 2014

作者： Dressler, Judson Bowen, Calvert L. Moody, William Koepke, Jason Department of Computer Science Rice University HoustonTexas United States Johns Hopkins University Applied Physics Lab LaurelMD United States School of Computing Clemson University ClemsonSouth Carolina United States Towson University BaltimoreMaryland United States

ISBN: (纸本)9789949954407

The United States, including the department of Defense, relies heavily on information systems and networking technologies to efficiently conduct a wide variety of missions across the globe. With the ever-increasing rate of cyber attacks, this dependency places the nation at risk of a loss of confidentiality, integrity, and availability of its critical information resources;degrading its ability to complete the mission. In this paper, we introduce the operational data classes for establishing situational awareness in cyberspace. A system effectively using our key information components will be able to provide the nation's leadership timely and accurate information to gain an understanding of the operational cyber environment to enable strategic, operational, and tactical decision-making. In doing so, we present, define and provide examples of our key classes of operational data for cyber situational awareness and present a hypothetical case study demonstrating how they must be consolidated to provide a clear and relevant picture to a commander. In addition, current organizational and technical challenges are discussed, and areas for future research are addressed. © 2014 NATO CCD COE.

关键词： Network security

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Mobile PET insert for simultaneous PET/MRI imaging

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Physica Medica 2016年 32卷 231-231页

作者： Marcin Zielinski D. Alfs T. Bednarski P. Białas E. Czerwiński A. Gajos B. Głowacz M. Gorgol B. Jasińska D. Kamińska G. Korcyl P. Kowalski T. Kozik W. Krzemień E. Kubicz M. Mohammed M. Pawlik-Niedźwiecka S. Niedźwiecki M. Pałka L. Raczyński P. Moskal Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University S. Łojasiewicza 11 30-348 Kraków Poland Department of Nuclear Methods Institute of Physics Maria Curie-Sklodowska University Pl. M. Curie-Sklodowskiej 1 20-031 Lublin Poland High Energy Physics Division National Centre for Nuclear Research A. Soltana 7 05-400 Otwock-Świerk Poland Świerk Computing Centre National Centre for Nuclear Research A. Soltana 7 05-400 Otwock-Świerk Poland

Access to the anatomical and functional information about the body interior is possible with tomography techniques relying on the registration of radiation from the tissues. Modern medicine offers: Positron Emission Tomography, Magnetic Resonance and computer Tomography. One of the present technological challenges is to combine the PET and MR scanners to work as single device to provide PET/MR images. Presented solution of a portable-PET scanner will allow simultaneous registration of PET and MR images utilizing existing MR scanners. The developed device is based on the strip-PET concept consisting of detection modules, each build from a plastic scintillator strip connected at both ends with silicon photomultipliers array. In the proposed solution determination of the point of annihilation along the direction of the gamma quanta flight path, is based on the time difference registered in various detection modules. It is important to stress that the utilized silicon photomultipliers are insensitive to the MR magnetic field. In order to position two tomographic images with respect to each other we will use watermarks, seen by MRI system. Since this method explicitly specify the position of the MRI with respect to PET scanner therefore it enables for synchronize both tomographic images. The advantage of this solution is to eliminate the possibility of artifacts in tomographic images hindering the identification of potentially cancerous lesions. In the talk we will present developed solution of a mobile-PET insert to MR scanners. The presentation will include the characteristics of a proposed device together with the advantages over present solutions.

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A method of grammar learning for questions in nature Chinese language

A method of grammar learning for questions in nature Chinese...

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2014 International Conference on Advanced Control, Automation and Robotics (ACAR2014)

作者： H.Song J.W.Zhu T.Lin W.C.Chen B.Chen Institute of Information Engineering Yangzhou University Department of Computer Science and Engineering Guelph University Institute of Computing Technology Chinese Academy of Sciences Computer Science and Applied Mathematics University of Evansville

ISBN: (纸本)9781784660468

NLU-based question understanding is one of the key technologies in the application and promotion of the Q&A system. Due to limitations of the method of artificial acquisition on grammar, it failed to meet the practical demands of creation of large-scale grammar library. This paper proposes and implements a method of machine grammar learning, using 2-frequent sequences with gap condition covering grammar. Firstly, this method gets all the 2-frequent sequences with gap condition and assesses its quality according to its coverage and continuity. And then, considering the expansibility and accuracy of grammar, we compare the structure and set option elements of grammar, and remove the structures in the grammar which caused ambiguity referred to the existing standard grammar. The results of experiments on text-corpus China Telecom show that the efficiency of grammars acquired by this method is more than 95.2%. Compared with existing methods, the proposed method in this paper does not rely on the composition and structure of grammar, but clarify the semantic association between the grammar elements.

关键词： grammar learning 2-frequent sequences with gap condition option element ambiguous element

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Measuring phase derivatives in digital holographic interferometry

Measuring phase derivatives in digital holographic interfero...

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Digital Holography and Three-Dimensional Imaging, DH 2014

作者： Rajshekhar, Gannavarpu Rastogi, Pramod Quantitative Light Imaging Laboratory Department of Electrical and Computer Engineering Beckman Institute for Advanced Science and Technology University of Illinois at Urbana-Champaign Urbana-61801 IL United States Applied Computing and Mechanics Laboratory Ecole Polytechnique Fédérale de Lausanne 1015 Lausanne Switzerland

We discuss pseudo Wigner-Ville distribution based phase derivative estimation techniques in digital holographic interferometry. These techniques address the major challenges associated with measuring phase derivatives... 详细信息

ISBN: (纸本)9781557523082

关键词： Wigner-Ville distribution

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Novel plastic scinitllators for the fully digital and MRI compatible J-PET scanner

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Physica Medica 2016年 32卷 232-232页

作者： Anna Wieczorek D. Alfs T. Bednarski P. Białas E. Czerwiński A. Gajos B. Głowacz M. Gorgol B. Jasińska D. Kamińska G. Korcyl P. Kowalski T. Kozik W. Krzemień E. Kubicz M. Mohammed M. Pawlik-Niedźwiecka S. Niedźwiecki M. Pałka L. Raczyński P. Moskal Faculty of Physics Astronomy and Applied Computer Science Jagiellonian University S. Łojasiewicza 11 30-348 Kraków Poland Institute of Metallurgy and Materials Science of Polish Academy of Sciences W. Reymonta 25 30-059 Kraków Poland Department of Nuclear Methods Institute of Physics Maria Curie-Sklodowska University Pl. M. Curie-Sklodowskiej 1 20-031 Lublin Poland High Energy Physics Division National Centre for Nuclear Research A. Soltana 7 05-400 Otwock-Świerk Poland Świerk Computing Centre National Centre for Nuclear Research A. Soltana 7 05-400 Otwock-Świerk Poland

Jagiellonian Postitron Emission Tomography (J-PET) scanner based on plastic scintillators has been developed at the Jagiellonian University. This innovative solution enables cost effective construction of PET detector with large field of view. At present we are working on the solution which would allow for the simultaneous PET and Magnetic Resonance Imaging (MRI). For that purpose we will use silicon photomultiplier (SiPM) readout which can be applied in the strong magnetic field of the MRI scanner. In this talk we will present results of the development of a novel scintillator material (referred to as the J-PET scintillator). The purpose of the development was the elaboration of scintillator with optical properties allowing for more efficient registration of photons with SiPM array with respect to the presently available plastics scintillators and at the same time with the superior timing characteristics. The novelty of the elaborated concept lies in usage of 2-(4-styrylphenylbenzoxazole) as a scintillation additive – wavelength shifter. The substance has been used for the first time as a scintillator dopant. J-PET scintillators were manufactured via bulk polymerization of styrene or vinyltoluene and the optimal concentration of the 2-(4-styrylphenylbenzoxazole) was set by maximizing the light output and timing properties. In the talk properties of J-PET scintillators will be presented and discussed in view of its application for the PET/MR imaging, and the performance of the developed material will be compared to the properties of commercially available scintillators. Disclosure Authors disclose any relationship that may bias the presentation

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Automated domain-specific feature selection for classificationbased segmentation of tomographic medical image data 3

Automated domain-specific feature selection for classificati...

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3rd International Workshop on Innovative Simulation for Health Care, IWISH 2014

作者： Zwettler, Gerald Backfrieder, Werner Bio- and Medical Informatics Research and Development Department University of Applied Sciences Upper Austria Softwarepark 11 Hagenberg4232 Austria School of Informatics Communication and Media University of Applied Sciences Upper Austria Softwarepark 11 Hagenberg4232 Austria Research Group Scientific Computing Faculty of Computer Science University of Vienna Währingerstrasse 29/6.21 Vienna1090 Austria

ISBN: (纸本)9788897999379

Classification-based segmentation is an approach to establish generic analysis of medical image data. Significant feature sets covering different characteristics of regions to segment allow for robust discrimination of topologically defined classes. In this work a method for automated domain-specific feature selection to achieve a higher level of predictability is presented, incorporating multivariate feature analysis. For calculation of the probability density function, different approaches, like histogram analysis, enumeration of the entire feature space or umbrella Monte Carlo Integration are investigated. Furthermore, meta features calculated on entire classification results rather than on particular regions are introduced. Predictability of both, single local and meta features, is evaluated for different medical datasets as well for simulated intensity volumes, allowing testing and evaluating specific classification problems. The automated feature selection proofs to be accurate for classification-based segmentation utilizing well-known machine learning approaches.

关键词： Classification (of information)

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Visualizing the Five-dimensional Torus Network of the IBM Blue Gene/Q

Visualizing the Five-dimensional Torus Network of the IBM Bl...

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Workshop on Visual Performance Analysis (VPA)

作者： Collin M. McCarthy Katherine E. Isaacs Abhinav Bhatele Peer-Timo Bremer Bernd Hamann Department of Computer Science University of California Davis California USA Center for Applied Scientific Computing Lawrence Livermore National Laboratory Livermore California USA

Understanding the interactions between a parallel application and the interconnection network over which it exchanges data is critical to optimizing performance in modern supercomputers. However, recent supercomputing architectures use networks that do not have natural low-dimensional representations, making them difficult to comprehend or visualize. In particular, high-dimensional torus networks are common and are used in four of the top ten supercomputers and eight of the top ten on the Graph500 list. We present a new visualization of five-dimensional torus networks. We use four connected views depicting the network at different levels of detail, allowing analysts to observe general large-scale traffic patterns while simultaneously viewing individual links or outliers in any specific section of the network. We demonstrate this approach by analyzing network traffic for a pF3D simulation running on the IBM Blue Gene/Q architecture, and show how it is both intuitive and effective for understanding and optimizing parallel application behavior.

关键词： Three-dimensional displays Data visualization Measurement Context Multiprocessor interconnection Supercomputers

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Accurate radio distance estimation by phase measurements with multiple frequencies

Accurate radio distance estimation by phase measurements wit...

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International Conference on Indoor Positioning and Indoor Navigation (IPIN)

作者： Mathias Pelka Christian Bollmeyer Horst Hellbrück Department of Electrical Engineering and Computer Science Luebeck University of Applied Sciences (LUAS) Germany University of Luebeck Graduate School for Computing in Medicine and Life Sciences Germany

Indoor localization is important for logistics, industrial applications and for several consumer applications. In the area of logistics, e.g. warehouses, localization accuracy within a few meters is desired. Available radio based systems within that accuracy are neither cost effective nor easy to deploy. Distance estimation together with triangulation are one of the standard solutions for localization. In this work, we propose phase measurements between two wireless sensor nodes for distance estimation. We introduce a mathematical model to estimate distances from phase measurements with multiple frequencies and provide a systematic analysis of possible sources of errors. Additionally, we derive requirements, e.g. resolution for a phase measurement unit to achieve a given accuracy. We present measurements for evaluation to confirm our theoretical results. Our implementation comprises a low cost IEEE 802.15.4 hardware with a built-in phase measurement unit. We implement the developed algorithm for distance estimation in our wireless sensor networks and use two wireless sensor nodes to perform a phase measurement. The contributions of the paper comprise a new model for phase measurements to estimate distances and a preliminary evaluation with our hardware.

关键词： Phase measurement Accuracy Estimation Frequency measurement Receivers Wireless sensor networks Indoor navigation

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11th German Conference on Chemoinformatics (GCC 2015) Abstracts

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JOURNAL OF CHEMINFORMATICS 2016年第SUPPL 1期8卷 1-27页

作者： [Anonymous] GDCh-CIC Division Associated Board Member Beilstein-Institut zur Förderung der Chemischen Wissenschaften Trakehner Str. 7-9 60487 Frankfurt Germany. ufechner@beilstein-institut.de. Division Medicinal Chemistry Amsterdam Institute for Molecules Medicines and Systems (AIMMS) VU University Amsterdam The Netherlands. Centre for Bioinformatics Uni Hamburg Bundesstr. 43 20146 Hamburg Germany. Sanofi-Aventis Deutschland GmbH 65926 Frankfurt am Main Germany. stefan.guessregen@***. Sanofi-Aventis Deutschland GmbH 65926 Frankfurt am Main Germany. GlaxoSmithKline Stevenage SG1 2NY UK. nicola.j.richmond@***. Discngine Paris 75011 France. Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Germany. marwin.segler@wwu.de. Organisch-Chemisches Institut Westfälische Wilhelms-Universität Münster Germany. Bundeskriminalamt Wiesbaden Central Analytics II 65173 Wiesbaden Germany. Department of Chemistry and Biochemistry University of California Santa Barbara CA 93111 USA. shea@chem.ucsb.edu. Department of Chemistry and Biochemistry University of California Santa Barbara CA 93111 USA. Chemistry Department Ludwig-Maximilians-Universität München Butenandtstr. 7 81377 Munich Germany. Inorganic Chemistry and Center for Nanointegration University of Duisburg-Essen Essen Germany. CAM-D Technologies Essen Germany. Institute for Bioinformatics and Chemoinformatics Westphalian University of Applied Sciences Recklinghausen Germany. Institute for Bioinformatics and Chemoinformatics Westphalian University of Applied Sciences Recklinghausen Germany. achim.zielesny@w-hs.de. Leiden University Leiden Netherlands. j.fraaije@chem.leidenuniv.nl. Culgi BV Berlin Germany. Physikalische Chemie III TU Dortmund 44227 Dortmund Germany. stefan.kast@tu-dortmund.de. Centre for Molecular Informatics Department of Chemistry University of Cambridge Lensfield Road Cambridge CB2 1EW United Kingdom. kcb27@cam.ac.uk. Centre for Molecular Informatics Department of Chemistry

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