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Developments for technologies were initiated by the European Commission to improve future response capabilities
and strategies to prevent terrorist attacks, to reduce the vulnerability to terrorism and to minimize the extent of damage from
terrorist attacks. CBRN civil protection faces a growing significance in this concept and modern detectors and detection
systems play the key role for a future reliable functioning that counters terrorism in Europe. The European Union is
supporting the project CREATIF which is dedicated to provide a communication platform for technology users and decision
makers, providers, and testers. First ideas were designed, strategies developed, preconditions and rules were named for a
future internationally recognized certification system. A concept for a future European Certification System for CBRNE
Sensor Systems and Devices and Processes has been developed, which is described in more detail.
Threat detection and imaging
(2007)
Digital detectors such as phosphor imaging plates (IP) and digital detector arrays (DDA) allow radiographic inspection with higher efficiency and improved image quality in comparison to the classic film technique. Mobile X-ray flash tubes are used routinely for veterinarian and security applications. New high sensetive IPs and DDAs enable to apply them for inspection of light materials with low X-ray attenuation as in aluminium, plastics and composites. A versatile computed tompgraphy (CT) system was developed for in situ inspection of large aircraft components under production conditions. A gate based planar computed tomograph wsa developed and testes for inspection of integrety of the stringer incorporation. Successful test trials were performed to prove the detection rate of cracks in embedded stringers. Honey comb structures of aircrafts have to be inspected for water inclusions during in-service inspections. Thermography is a powerful method for in house inspections when variations in temperature caused e. g. by sunshine can be excluded. A new X-ray diaphragm was developed for mobile back scatter measurements of large components. This method is insensitive to heat alterations in the field and thus can be applied also outdoors.
Bei der Normgestaltung für Speicherfolien sind die Auswirkungen von Metallfolien und Metallfolienkombinationen auf die Bildqualität von Speicher-folienaufnahmen nicht ausreichend berücksichtigt worden. Es ist bekannt, dass bei Film - Metallfolien - Kombinationen zusätzlich zur Änderung der optischen Dichte und der Filmgranularität auch Änderungen der inneren Unschärfe durch den seitli-chen Energietransport in der Film Metallfolien - Kombination entstehen, welche überwiegend durch ausgelöste Elektronen und zum Teil durch sekundäre Strahlung hervorgerufen werden. Gleichzeitig dienen die Metallfolien bei Röntgenaufnahmen mit Film als Streustrahlfilter und können zur Verbesserung des Bildkontrastes bei-tragen. Die Mechanismen zur Erzeugung des virtuellen Röntgenbildes und dessen Visualisierung sind in Speicherfolien nicht mit denen in einem Röntgenfilm iden-tisch. Demzufolge können die in den Normen festgelegten Vorschriften zum Einsatz von Metallfolien in der Filmradiographie nicht auf Speicherfolien uneingeschränkt übertragen werden. Anhand der hier erzielten Ergebnisse lassen sich Empfehlungen zum zukünftigen Einsatz der Metallfilter und -folienkombinationen für die Speicher-folientechnik zur Verbesserung der Bildgüte ableiten.
Einfluss von Metall-Speicherfolien-Kombinationen auf die Bildqualität in der Computer-Radiographie
(2008)
Industrial Radiology
(2006)
Throughout human history, wood has been used for various purposes: for
building shelters, houses and bridges, for manufacturing furniture and
household or agricultural appliances (from ploughs to spoons), as burning
material or simply as walking sticks. Contemporarily, vast amounts of wood
are going into paper production. As a consequence, different qualities of
wood are selected appropriately for the various applications. Beams incorporated
into buildings and constructions have to be sturdy and durable;
boards for furniture are supposed to be free of knots or are expected to have
certain ornamental structures. As long as wood is not simply destined for
burning it should be free of undesired knots or internal damages such as rot
or worm holes. Particularly in cases of infestation with wood destroying
fungi that definitely impairs mechanical strength and even may generate
hollows such damages are frequently invisible from the outside. Radiographic
methods are capable to detect internal damages as well as hidden
knots without the need of drilling holes or cutting a specimen to pieces.
The most thoroughly method to visualise the interior of a wooden specimen
is tomography which shows annual growth rings in their complete circumference
and all the knots or damages that might be included. However, some
of them as well as patterns of annual rings suitable for dendrological investigations
are recognisable with a less laborious method that might be applicable
even in the field, i.e. contemporary digital radiography combined with
image processing. Samples of lumber shall be presented showing the typical
annual ring structures and some infested areas.
The detection of defects in aircraft components or parts of a power plant or mines in the ground is connected with the task to distinguish between signals caused be the item searched for and noisy signals from other sources. The reliability of the system is the better the better the system is in detecting the wanted signal and avoiding false alarms caused by noise. It is usual to measure the reliability of diagnostic systems in terms of ROC-curves (Re-ceiver Operating Characteristics) and POD-curves (Probability of Detec-tion). The ROC curves describe the POD versus Probability of False Alarm with growing system sensitivity along the curve. POD curves describe the Probability of Detection for a fixed sensitivity for a variation of item sizes or depths. Reliability of the whole system is always a composition of the physics
and technique, application influences and the human factors. For the scien-tific understanding and possibilities of improvement, decomposition accord-ing to a modular model is helpful. The authors present their experiences with the reliability evaluation of metal detectors for humanitarian demining and an NDT system of mechanized ultrasonic phased array testing of copper welds. The special concern in demining is the influence of soil types, detec-tors and the experiences of human beings.