TY - CONF A1 - Jaenisch, Gerd-Rüdiger A1 - Wieder, Frank A1 - Vogel, Justus A1 - Ewert, Uwe A1 - Bellon, Carsten A1 - Messerschmid, Magdalena ED - Xu, C. T1 - Scatter imaging – Simulation of aperture focusing by deconvolution N2 - X-ray scatter imaging is a well-established NDT technique to inspect complex objects using only a single-sided access. We present a specially designed multi-slit scatter camera consisting of several twisted slits which are parallelly arranged in a metal block. The camera projects one image per slit to the digital detector array, where the images are overlaying each other. The aperture is corrected based on a de-convolution algorithm to focus the overlaying projections into a single representation of the object. To achieve high scatter intensities from an object, it is necessary to optimize the parameters of the scatter system by simulation. T2 - IEEE Far East NDT New Technology & Application Forum CY - Xi'an, China DA - 22.06.2017 KW - Scatter imaging KW - Computer simulation KW - Aperture focusing KW - Deconvolution PY - 2018 SN - 978-1-5386-1615-4 DO - https://doi.org/10.1109/FENDT.2017.8584606 SP - 301 EP - 306 PB - IEEE CY - Piscataway, NJ AN - OPUS4-48395 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krause, Martin A1 - Maierhofer, Christiane A1 - Ewert, Uwe T1 - Prüfung von bewehrtem Beton mit Radar, Ultraschall-Impulsecho und Durchstrahlverfahren (Erweitertes Abstract) T2 - Erstes franz.-dt. Seminar für zerstörungsfreie Prüfung CY - Metz, Frankreich DA - 1995-10-12 KW - Beton, bewehrt KW - Prüfung KW - Radar KW - Ultraschall-Impulsecho KW - Durchstrahlungsverfahren PY - 1995 CY - Metz AN - OPUS4-594 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kannengießer, Thomas A1 - Rethmeier, Michael A1 - Portella, Pedro Dolabella A1 - Ewert, Uwe A1 - Redmer, Bernhard T1 - Assessment of hot cracking behaviour in welds N2 - Hot crack assessment during production and processing of metallic materials is an essential prerequisite for the safety of welded structures. The hot cracking investigations presented here were carried out as part of a study aimed at the development of Cr/Ni low transformation temperature filler materials. Low transformation temperature alloys open up the possibility for welding high strength steels. The externally loaded Modified Varestraint Transvarestraint hot cracking test was employed in the experiments described. The hot cracking resistance was evaluated with the help of light microscopy applied at the specimen surface. The proportionality between hot cracking susceptibility and Cr/Ni alloy content was explained by the altered solidification kinetics and by the enlarged solidification interval. The internal crack paths and the three-dimensional structure of the crack net in the material volume were examined using X-ray computer tomography. The total crack lengths for different material depths and circumjacent rectangular volumes, respectively, were be determined. An increasing hot cracking susceptibility with increasing Cr/Ni alloy content was also be established for the specimen volume. KW - Hot cracking KW - Low transformation temperature (LTT) alloy KW - Modified varestraint transvarestraint (MVT) hot cracking test KW - X-ray computer tomography PY - 2011 DO - https://doi.org/10.3139/146.110545 SN - 1862-5282 VL - 102 IS - 8 SP - 1001 EP - 1006 PB - Carl Hanser CY - München AN - OPUS4-24400 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ewert, Uwe T1 - Mobile Computed Tomography for Inspection of Welded Pipes T2 - 8th International Conference on NDE CY - Berlin, Germany DA - 2010-09-29 PY - 2010 AN - OPUS4-22782 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Kupsch, Andreas A1 - Beckmann, Jörg A1 - Ewert, Uwe A1 - Lange, Axel A1 - Hentschel, Manfred P. ED - Beyerer, J. T1 - Threat detection and characterisation by spectroscopic THz-imaging T2 - 2nd Security Research Conference "Future Security" CY - Karlsruhe, Germany DA - 2007-09-12 KW - Terahertz-Radiography KW - Explosives PY - 2007 SN - 978-3-86644-147-7 SP - 155 EP - 158 PB - Universitätsverl. CY - Karlsruhe AN - OPUS4-16101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kupsch, Andreas A1 - Beckmann, Jörg A1 - Ewert, Uwe A1 - Hentschel, Manfred P. A1 - Lange, Axel T1 - Terahertz-Radiographie riskanter Substanzen ohne Strahlengefährdung T2 - DGZfP-Jahrestagung 2007 CY - Fürth, Deutschland DA - 2007-05-14 KW - Terahertz-Radiographie KW - Explosivstoffe KW - Nichtmetallische Werkstoffe PY - 2007 SN - 978-3-931381-98-1 SP - 1 EP - 10 PB - DGZfP CY - Berlin AN - OPUS4-16100 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kupsch, Andreas A1 - Beckmann, Jörg A1 - Ewert, Uwe A1 - Hentschel, Manfred P. A1 - Lange, Axel T1 - Terahertz-Wellen: Radiographie ohne Strahlengefährdung N2 - Mit dem Einsatz von Terahertz-Wellen eröffnen sich gegenüber Röntgenstrahlung neuartige Möglichkeiten der Radiologie. Von der dielektrischen Materialcharakterisierung nicht metallischer Werkstoffe bis zur Detektion des Innenlebens von unkonventionellen Spreng- und Brandvorrichtungen (USBV) wird ein großes Anwendungsspektrum für die bildgebende zerstörungsfreie Prüfung abgedeckt. Die physiologische Unbedenklichkeit der Strahlung favorisiert sie auch für Personenkontrollen an Flughäfen. Das Prinzip eines modernen zeitauflösenden Terahertz-Spektrometers mit einer Ortsauflösung bis 0,3mm und einem Frequenzbereich von 0,1 bis 2,2THz wird erläutert sowie die Wechselwirkung mit Materie. Die Besonderheiten von THz-Topogrammen werden am Beispiel einer Briefbombenattrappe mit Röntgen-Radiogrammen verglichen. KW - Terahertz-Radiographie KW - Explosivstoffe KW - Nichtmetallische Werkstoffe PY - 2008 UR - http://materialstesting.de/directlink.asp?MP100891 SN - 0025-5300 VL - 50 IS - 6 SP - 341 EP - 348 PB - Hanser CY - München AN - OPUS4-17598 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ewert, Uwe A1 - Osterloh, Kurt A1 - Kupsch, Andreas A1 - Lange, Axel A1 - Beckmann, Jörg A1 - Hentschel, Manfred P. ED - Beyerer, J. T1 - Advanced radiological technologies for imaging and characterisation of threats T2 - 2nd Security Research Conference "Future Security" CY - Karlsruhe, Germany DA - 2007-09-12 KW - Threat Detection KW - Dual Energy KW - Multiple View Inspection KW - Terahertz Imaging KW - Explosives PY - 2007 SN - 978-3-86644-147-7 SP - 116 EP - 119 PB - Universitätsverl. CY - Karlsruhe AN - OPUS4-18348 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pavlovic, Mato A1 - Ronneteg, U. A1 - Müller, Christina A1 - Ewert, Uwe A1 - Boller, C. T1 - Safe product design - the role of the NDE reliability analysis N2 - When pushed to the limits of their detection capability, NDE systems do not produce consistent hit/miss indications. Their capability of detecting small defects is therefore expressed in terms of POD. An adequate NDE system is required to ensure the structural integrity. In conventional signal response analysis, the POD is expressed as a function of the defect size, and its adequacy for the inspection task is tested against the maximum allowable defect size which will not undermine the structural integrity. Analyses of modern structures show that other parameters, beside the defect size, can both significantly influence the POD and determine the severity of the defect for the structure. Within the multi-parameter reliability analysis, the POD is expressed as a function of those influencing parameters. When determining the adequacy of the NDE system, the capability of detecting a defect has to be expressed and tested against the critical value of exactly that parameter that determines defects severity for the structure. Failing to do so can lead to a rejection of the healthy, or acceptance of the bad part. The principle is demonstrated on the example of the Transmit-Receive Longitudinal (TRL) ultrasonic inspection of the iron cast component for semi-elliptical surface defects. T2 - 18th WCNDT - World conference on nondestructive testing CY - Durban, South Africa DA - 16.04.2012 KW - Reliability KW - Probability of detection (POD) KW - Multi-parameter KW - Ultrasonics KW - Transmit receive longitudinal (TRL) PY - 2012 SN - 978-0-620-52872-6 SP - 1 EP - 9 (Paper 310) AN - OPUS4-27581 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Christina A1 - Bertovic, Marija A1 - Pavlovic, Mato A1 - Kanzler, Daniel A1 - Ewert, Uwe A1 - Pitkänen, J. A1 - Ronneteg, U. T1 - Holistically evaluating the reliability of NDE systems - paradigm shift N2 - New methodologies for evaluating the reliability of NDE systems are discussed in accordance with the specific requirements of industrial application. After a review of the substantive issues from the previous decades, the go forward guidance is concluded. For high safety demands a quantitative probability of detection (POD) created from hit miss experiments or signal response analysis and ROC (Receiver Operating Characteristics) are typically created. The modular model distinguishes between the influence of pure physics and technique, industrial application factors and the human factor and helps to learn what factors are covered by modelling, open or blind trials. A new paradigm is offered to consider the POD or reliability of the system as a function of the configuration of input variables and use it for optimisation rather than for a final judgement. New approaches are considered dealing with real defects in a realistic environment, affordable but precisely like the Bayesian approach or model assisted methods. Among the influencing parameters, the human factor is of high importance. A systematic psychological approach helps to find out where the bottlenecks are and shows possibilities for improvement. T2 - 18th WCNDT - World conference on nondestructive testing CY - Durban, South Africa DA - 16.04.2012 KW - Reliability of NDE KW - POD KW - ROC KW - Modular Model KW - Multiparameter-POD KW - Bayesian Approach KW - Human Factor PY - 2012 SN - 978-0-620-52872-6 SP - 1 EP - 14 (Paper 591) AN - OPUS4-27579 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ewert, Uwe T1 - Prediction of the visibility of indications in X-ray computed tomography by the contrast detail diagram N2 - X-Ray Computed Tomography (CT) is applied in industry for flaw detection, flaw evaluation and dimensional measurement. This requires the correct CT system settings for sufficient visibility and detectability of flaws and structure elements. The visibility of indications for human observers on a monitor depends on the square root of the reconstructed flaw area (here pores with diameter < ½ inch) in the cross sectional 2D images, the Contrast to Noise Ratio (CNR) and the Modulation Transfer Function (MTF). This applies also to 2D-projections, meaning also to “normal” digital radiographs. The ASTM guide E 1441 describes three essential functions for prediction of the visibility of small circular indications in slice images of a 3D reconstruction or a 2D reconstruction. This is the Contrast Discrimination Function (CDF), the MTF (see also the revision of ASTM E 1695), and the Contrast Detail Dose (CDD) function. The prediction of the visibility of circular indications in reconstructed slice images can be determined from the Contrast Detail Dose function, which is the combination of CDF and MTF and a physiological factor c. The measurement procedures and formulas for the prediction of the detail visibility by CDD will be corrected, tested and verified by modelling and in a Round Robin Test with modern commercial 3D CT systems of different manufacturers. Conclusions will be reported and recommendations will be given for the correct psychological factor c and the consideration of the influence of artefacts, as e.g. cupping and scatter. T2 - International Symposium on Nondestructive Characterization of Materials CY - Portoroz, Slovenia DA - 17.09.2019 KW - Nondestructive Testing KW - Computed Tomography KW - Visibility of Indications KW - Prediction from system parameters PY - 2019 AN - OPUS4-50524 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zhua, L A1 - Ewert, Uwe A1 - Xianga, X. A1 - Pengc, Y. A1 - Wanga, X. T1 - Synchrotron phase-contrast CT to segment the structure boundaries of a TRISO-coated particle N2 - Tri-structural Isotropic (TRISO)-coated particle is the fission energy source and the first safety barrier in high temperature gas-cooled reactors (HTGRs). The integrity of TRISO particle should be carefully tested before operation because the shape may affect the failure possibility of the particles, leading to increased risk of fission product release. Due to the large difference in density between the kernel and the coating layers in TRISO particles, traditional X-ray radiography cannot achieve a good image quality in terms of identifying coating layers reliably, while phase-contrast CThas the advantageof being sensitive to boundaries. This paperpresents a non-destructive test and evaluation (NDT&E) method to facilitate 3-dimensional (3D) measurement of a TRISO particle's structure, using a synchrotron phase-contrast CT. After reconstructed, the TRISO particle was rendered in a 3D space and the thickness and asphericity of the TRISO particle's layers were measured. It was found that the thickness of coating layers of the tested particle obeys Gaussian distribution. The deviation of thicknesses of the kernel and the other four layers is −2.42%, −16.32%, 26.51%, 0.98% and 7.49% compared with the design parameters. The deviation of asphericity of the kernel, IPyC and OPyC layers is −11.51%, −0.41% and 3.39%, respectively. The effect of the deviations on the temperature distribution and failure probability calculation of the particle will be investigated in the future. KW - TRISO KW - 3D visualization KW - 3D particle analysis KW - Three-dimensional measurement PY - 2019 DO - https://doi.org/10.1016/j.ndteint.2019.01.003 VL - 103 SP - 12 EP - 18 PB - Elsevier Ltd. AN - OPUS4-47303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Z., Zhang A1 - Ewert, Uwe A1 - Barrett, T. D. A1 - Bond, L. J. T1 - Paper Watermark Imaging using Electron and Low Energy X-ray Radiography N2 - Historians and librarians are interested in watermarks and mould surface patterns in historic papers, because they represent the “fingerprints” of antique papers. However, these features are usually covered or hidden by printing, writing or other media. Different techniques have been developed to extract the watermarks in the paper while avoiding interference from media on the paper. Beta radiography provides good results, but this method cannot be widely used because of radiation safety regulations and the long exposure times required due to weak isotope sources employed. In this work, two promising methods are compared which can be used to extract digital high-resolution images for paper watermarks and these are electron radiography and low energy X-ray radiography. For electron radiography a “sandwich” of a lead sheet, the paper object, and a film in a dark cassette, is formed and it is exposed at higher X-ray potentials (> 300 kV). The photoelectrons escaping from the lead sheet penetrate the paper and expose the film. After development, the film captures the watermark and mould surface pattern Images for the paper being investigated. These images are then digitized using an X-ray film digitizer. The film employed could potentially be replaced by a special type of imaging plate with a very thin protection layer to directly generate digital Images using computed radiography (CR). For the second method, a low energy X-ray source is used with the specimen paper placed on a digital detector array (DDA). This method directly generates a low energy digital radiography (DR) image. Both methods provide high quality images without interference from the printing media, and provide the potential to generate a “fingerprint” database for historical papers. There were nevertheless found to be differences in the images obtained using the two methods. The second method, using a low energy X-ray source, has the potential to be integrated in a portable device with a small footprint incorporating user safety requirements. Differences obtained using the two methods are shown and discussed. T2 - 45th Annual Conference on Review of Progress in Quantitative Nondestructive Evaluation (QNDE) CY - Burlington, VT, USA DA - 15.07.2018 KW - X-ray Radiography KW - Paper watermark PY - 2019 SN - 978-0-7354-1832-5 DO - https://doi.org/10.1063/1.5099750 SN - 0094-243X VL - 2102 IS - 1 SP - 030004-1 EP - 030004-9 PB - American Institute of Physics AN - OPUS4-49922 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kolkoori, Sanjeevareddy A1 - Wrobel, Norma A1 - Osterloh, Kurt A1 - Redmer, Bernhard A1 - Deresch, Andreas A1 - Ewert, Uwe T1 - Hochenergieradiographie - Erkennung von Einzelheiten in großen, komplexen Schichttiefen N2 - Zur Durchstrahlung großer, dichter Objekte reichen die Energien, die mit normalen Röntgenröhren erzielt werden können, ab gewissen Schichtdicken nicht mehr aus. Als hochenergetische Strahlenquellen stehen Kobalt-60 und Elektronenbeschleuniger zur Verfügung. Als Einschränkung der Hochenergieradiographie ist der geringere Kontrast besonders beim Vorhandensein leichterer Objekte umgeben von Körpern bestehend aus schweren Elementen anzusehen. Es ist daher zu erwarten, dass Objekte aus organischen Substanzen hinter dicken Schwermetallwänden oder in Bohrungen von Metallblöcken schwer zu erkennen sind. Im Gegensatz zu einem Gammastrahler wie Kobalt-60 mit den beiden Spektrallinien um 1,3 MeV besitzt die Bremsstrahlung aus einem Beschleuniger einen wesentlichen Anteil an niederenergetischer Strahlung, der fließend zu höheren Energien übergeht. Es wird hier untersucht, welche Signaturen von leichten Materialien in einer Umgebung aus Schwermetall bis zu welcher Dicke und bis zu welchem Komplexizitätsgrad erkennbar sind. Mit einem Betatron (JME X-ray Betatron 7,5 MeV) und einem Matrixdetektor (Perkin Elmer XRD 1621) wurden Aufnahmen von unterschiedlichen leichten Objekten angefertigt, die zunehmend in eine Umgebung aus Schwermetallen gestellt wurden. Mit unterschiedlichen Energieeinstellungen wurde untersucht, inwieweit eine Materialerkennung hinter welcher Abschirmung möglich ist. Die experimentellen Ergebnisse werden mit Simulationen verglichen, die mit einer Software zur Modellierung von Durchstrahlungsverfahren (aRTist) erzeugt wurden. Dabei wird dem Problem der Aufhärtung bei Anwendung von Bremsstrahlung Rechnung getragen. Die Ergebnisse können sowohl zur Erkennung von Fremdkörpern in Maschinen oder Pumpen als auch zur Überprüfung von Frachtladungen im Bereich der öffentlichen Sicherheit und bei Zollkontrollen dienen. T2 - DGZfP-Jahrestagung 2013 CY - Dresden, Germany DA - 06.05.2013 KW - Hochenergieradiographie KW - Containerprüfung KW - Materialerkennung PY - 2013 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-288589 SN - 978-3-940283-49-8 IS - DGZfP-BB 141 (Mo.2.A.4) SP - 1 EP - 9 PB - Deutsche Gesellschaft für zerstörungsfreie Prüfung e.V. (DGZfP) AN - OPUS4-28858 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Osterloh, Kurt A1 - Ewert, Uwe A1 - Zvizdic, D. A1 - Krstelj, V. T1 - Die EFNDT Arbeitsgruppe 5 'Öffentliche Sicherheit mit ZfP-Techniken' neu formiert N2 - Für die öffentliche Sicherheit wird gesorgt, indem Gefahren rechtzeitig entdeckt werden. Deren Ursprung kann im technischen oder menschlichen Versagen liegen, womit im englischen Sprachraum zwischen 'Safety' und 'Security' unterschieden wird. Hinsichtlich der Folgen verschwimmt aber dieser Unterschied, obwohl für deren Verhinderung unterschiedliche Zuständigkeiten existieren. Bezüglich des gemeinsamen Interesses und auch überlappender Methoden und Vorgehensweisen würden beide Seiten gewinnen können, wenn es eine Brücke zwischen ihnen gäbe. Eine solche zu schaffen hat sich die EFNDT Arbeitsgruppe (Working Group) 5 zur Aufgabe gestellt. Gestaltet werden soll sie durch gemeinsame Veranstaltungen und Seminaren, die zur Bildung von Konsortien und der Durchführung gemeinsamer Projekte führen sollen. T2 - DGZfP-Jahrestagung 2011 CY - Bremen, Germany DA - 03.05.2011 KW - EFNDT Working Group 5 KW - Technische und öffentliche Sicherheit KW - Gemeinsamkeiten in ZfP und öffentlicher Sicherheit KW - Brückenbildung zwischen Zuständigkeitsbereichen PY - 2011 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-250631 SN - 978-3-940283-33-7 VL - 127 SP - 1 EP - 5 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung (DGZfP) CY - Berlin AN - OPUS4-25063 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kolkoori, Sanjeevareddy A1 - Wrobel, Norma A1 - Deresch, Andreas A1 - Redmer, Bernhard A1 - Ewert, Uwe T1 - Dual high-energy X-ray digital radiography for material discrimination in cargo containers N2 - In this contribution, we present a dual high-energy X-ray imaging technique for cargo container inspection using the 'spectral high-energy X-ray attenuation method'. This method is based on attenuation of continuous highenergy spectra. The developed experimental technique consists of a betatron as high-energy (up to 7.5 MeV) X-ray source and a matrix detector with high spatial resolution (400 ìm) for digital X-ray imaging. In order to evaluate the material discrimination capability using dual high-energy X-ray imaging, a test specimen is proposed, comprising step wedges of different low and high atomic number (Z) materials. The selected X-ray spectra for the dual-energy experiments correspond to 3 MV and 7.5 MV acceleration potential of the betatron. We evaluated the ratio between low- and high-energy X-ray attenuation coefficients quantitatively based on simulated poly-energetic high-energy X-ray source spectra and the detector sensitivity using the 'analytical Radiographic Testing inspection simulation tool' (aRTist) developed at BAM. The simulated effective attenuation coefficients are compared with corresponding experimental results in order to establish a method for identification of low- and high-Z materials in the container. Finally, important applications of the proposed technique in the context of aviation security are discussed. T2 - ECNDT 2014 - 11th European conference on non-destructive testing CY - Prague, Czech Republic DA - 06.10.2014 KW - Digital radiography KW - NDT KW - High-energy X-ray imaging KW - Betatron KW - Digital detector array (DDA) KW - Container inspection KW - Material discrimination KW - Effective attenuation coefficient PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-322394 UR - https://www.ndt.net/?id=16430 SN - 1435-4934 VL - 19 IS - 12 SP - 1 EP - 10 PB - NDT.net CY - Kirchwald AN - OPUS4-32239 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bellon, Carsten A1 - Gollwitzer, Christian A1 - Fratzscher, Daniel A1 - Ewert, Uwe A1 - Jaenisch, Gerd-Rüdiger T1 - Simulation of complex scan paths for 3D reconstruction N2 - X-ray computed tomography (CT) is a volumetric (3D) Imaging diagnostic method, well established in the medical field, and in industrial NDE as well. Developments in industrial CT aim to extent the applicability to complex structures, which do not allow the access of all directions. This are e.g. limited view, data and angle CT applications. New reconstruction algorithms are required on one side, and the accuracy has to be improved on the other side. Numerical Simulation can support such developments by providing well defined data sets for the testing of reconstruction algorithms. This approach of virtual CT is realized within the radiographic simulator aRTist, developed by BAM. The poster shows the possibilities of this tool to consider complex scan paths. Simulated data sets have been reconstructed by an versatile backprojection algorithm. T2 - International symposium on digital industrial radiology and computed tomography CY - Berlin, Germany DA - 20.06.2011 KW - Radiographie KW - Computer-Simulation KW - 3D-Rekonstruktion PY - 2011 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-243928 SN - 978-3-940283-34-4 IS - DGZfP-BB 128 (Poster 17) SP - 1 EP - 4 PB - Deutsche Gesellschaft für zerstörungsfreie Prüfung e.V. (DGZfP) AN - OPUS4-24392 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gollwitzer, Christian A1 - Bellon, Carsten A1 - Deresch, Andreas A1 - Ewert, Uwe A1 - Jaenisch, Gerd-Rüdiger T1 - On POD estimations with radiographic simulator aRTist N2 - The computer simulation of radiography is applicable for different purposes in NDT such as for the qualification of NDT systems, the optimization of system parameters, feasibility analysis, model-based data interpretation, education and training of NDT/NDE personnel, and others. Within the framework of the European project PICASSO simulators will be adapted to support reliability assessments of NDT tasks. The radiographic simulator aRTist developed by BAM is well suited for this task. It combines analytical modelling of the RT inspection process with the CAD-orientated object description applicable to various industrial sectors such as power generation, aerospace, railways and others. The analytic model includes the description of the radiation source, the interaction of Radiation with the material of the part, and the detection process with special focus to DIR. To support reliability estimations the simulation tool is completed by a tool for probability of detection (POD) estimation. It consists of a user interface for planning automatic simulation runs with varying parameters, specifically defect variations. Further, an automatic image analysis procedure is included to evaluate the defect visibility and calculate the POD therefrom. T2 - International symposium on digital industrial radiology and computed tomography CY - Berlin, Germany DA - 20.06.2011 KW - Radiographie KW - Computersimulation KW - Probability of detection PY - 2011 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-245092 SN - 978-3-940283-34-4 IS - DGZfP-BB 128 (Tu.2.3) SP - 1 EP - 8 PB - Deutsche Gesellschaft für zerstörungsfreie Prüfung e.V. (DGZfP) AN - OPUS4-24509 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beckmann, Jörg A1 - Fratzscher, Daniel A1 - von Chrzanowski, Lars A1 - Ewert, Uwe T1 - Zeitaufgelöste THz-Spektroskopie für technische und zivile Sicherheitsanwendungen N2 - Vortrag über Zeitaufgelöste THz-Spektroskopie für technische und zivile Sicherheitsanwendungen T2 - DACH-Jahrestagung 2012 CY - Graz, Austria DA - 17.09.2012 KW - THz Spektroskopie KW - Technische und zivile Sicherheit PY - 2012 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-280013 SN - 978-3-940283-44-3 IS - DGZfP-BB 136 SP - Mi.1.C.4, 1 EP - 14 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung e.V. (DGZfP) AN - OPUS4-28001 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kanzler, Daniel A1 - Müller, Christina A1 - Pitkänen, J. A1 - Ewert, Uwe T1 - Bayesian approach for the evaluation of the reliability of non-destructive testing methods: combination of data from artificial and real defects N2 - The Probability of Detection (POD) is used to evaluate the detectability of non-destructive testing (NDT) systems. The POD is highly dependent on the amount of available data. The Bayesian approach provides a solution to compute POD-curves in case of a small amount of real defects without losing the necessary information. The result contains the needed information for the computation of POD-curves for real defects with an acceptable amount of information, even for sparse amount of data. In this paper is shown limitations of the Bayesian approach and how it can be applied to NDT. The Bayesian approach is applied in this case to the evaluation of radiographic testing. Bayesian approach is applied to determine POD-curves for the inspection techniques of nuclear fuel disposal canisters. The reason for using Bayesian approach is the high safety demands and also the low amount of real defects due to the high quality of the reliable production techniques. T2 - 18th WCNDT - World conference on nondestructive testing CY - Durban, South Africa DA - 16.04.2012 KW - Reliability KW - Probability of Detection KW - Real defect testing KW - Bayesian statistics KW - Radiographic testing PY - 2012 SN - 978-0-620-52872-6 SP - 1 EP - 6 (Paper 196) AN - OPUS4-27582 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -