TY - CHAP A1 - Müller-Veggian, Mattea A1 - Kops, Elena Rota A1 - Quin, Peng A1 - Herzog, Hans T1 - MRI Based Attenuation Correction for Brain PET Images T2 - Advances in medical engineering / [3rd RPT - Remagener Physiktage together with the Second Scientific Workshop of Medical Robotics, Navigation and Visualization ... Remagen ... 7.-9. März 2007]. Thorsten M. Buzug (ed.) Part 1. N2 - This work describes a procedure to yield attenuation maps from MR images which are used for the absorption correction (AC) of brain PET data. Such an approach could be mandatory for future combined PET and MRI scanners, which probably do not include a transmission facility. T1-weighted MR images were segmented into brain tissue, bone, soft tissue, and sinus; attenuation coefficients corresponding to elemental composition and density as well as to 511 keV photon energy were respectively assigned. Attenuation maps containing up to four compartments were created and forward projected into sinograms with attenuation factors which then were used for AC during reconstruction of FDG-PET data. The commonly used AC based on a radioactive (68Ge) transmission scan served as reference. The reconstructed radioactivity values obtained with the MRI-based AC were about 20% lower than those obtained with PET-based AC if the skull was not taken into account. Considering the skull the difference was still about 10%. Our investigations demonstrate the feasibility of a MRI-based AC, but revealed also the necessity of a satisfying delineation of bone thickness which tends to be underestimated in our first approach of T1-weighted MR image segmentation. Y1 - 2007 SN - 978-3-540-68763-4 U6 - https://doi.org/10.1007/978-3-540-68764-1_15 N1 - Springer proceedings in physics ; 114 SP - 93 EP - 97 PB - Springer CY - Berlin ER - TY - CHAP A1 - Helsper, Christoph A1 - Fissan, H. J. A1 - Franzen, H. ED - Benarie, Michel M. T1 - Particle Size Distributions of Combustion Aerosols T2 - Atmospheric Pollution 1978 : Proceedings of the 13th International Colloquium; 25-28 April 1978; Paris, France; Edited by Michel M. Benarie N2 - It has been observed that carcinogenic polycyclic aromatic hydrocarbons (PAH) are present in the atmosphere. Combustion processes are considered the most important sources for PAH. Among these, the burning of coal produces the highest emission, but in cities with high traffic density and low meteorological exchange activities, vehicle emissions determine the immission situation, especially in narrow streets. For estimating the potential health effects caused by PAH, it is sufficient to characterize the emission of PAH with respect to their physical state, concentrations, and, as far as the particulate phase is concerned, size distribution. The size distribution is important for transport phenomena, inhalation, and deposition in the respiratory tract. These parameters mainly depend on the combustion system, on system operating conditions, on the exhaust system, and on exhaust cooling conditions. At exhaust-gas temperatures in the range of ambient air temperatures, almost the whole emission of PAH is made up of particulate matter. Y1 - 1978 SN - 0-444-41691-9 U6 - https://doi.org/10.1016/S0166-1116(08)71583-8 SP - 263 EP - 266 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Bechstedt, U. A1 - Berg, Georg P. A. A1 - Hacker, U. A1 - Hardt, Arno A1 - Hürlimann, W. A1 - Maier, R. A1 - Martin, S. A1 - Meissburger, J. A1 - Römer, J. G. M. A1 - Possen, P. von A1 - Sagefka, T. T1 - BIG KARL and COSY T2 - The art and science of magnet design. A Festschrift in honor of Klaus Halbach. Vol. 1 Y1 - 1995 SP - 19 EP - 28 PB - Lawrence Berkeley Lab., Univ. of California CY - Berkeley, CA. ER - TY - CHAP A1 - Cresser, J. D. A1 - Häger, J. A1 - Leuchs, G. A1 - Rateike, Franz-Matthias A1 - Walther, H. T1 - Resonance fluorescence of atoms in strong monochromatic laser fields T2 - Dissipative systems in quantum optics. Ed. by Rodolfo Bonifacio. Topics in current physics. Vol. 27 N2 - The investigation of atomic resonance fluorescence has always been of special interest as a means for the determination of atomic parameters. In addition, information on the interaction mechanism between atoms and radiation can be obtained. In the standard fluorescence experiment the frequency distribution of the incident photons is larger than the natural width of the respective transition; as a consequence the correlation time in the photon-atom interaction is determined by the lifetime of the atoms in the excited state. With the development of lasers and especially of tunable dye lasers in recent years it became possible to study the case where the incident radiation has a spectral distribution which is narrower than the natural width. This corresponds to a correlation time of the incoming light wave which is much longer than the excited-state lifetime. In this chapter a survey of experiments on the resonance fluorescence of atoms in monochromatic laser fields will be given. Y1 - 1982 SN - 978-3-642-81719-9 U6 - https://doi.org/10.1007/978-3-642-81717-5_3 SP - 21 EP - 59 PB - Springer CY - Berlin ER - TY - CHAP A1 - Weber, Hans-Joachim T1 - Applied physics of compressible and incompressible fluids T2 - Critical care nephrology / [Hrsg.:] Claudio Ronco and Rinaldo Bellomo Y1 - 1998 SN - 978-94-010-6306-7 SP - 63 EP - 84 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Dikta, Gerhard T1 - Fundamentals of applied probability and basic statistics T2 - Critical care nephrology / [Hrsg.:] Claudio Ronco and Rinaldo Bellomo Y1 - 1998 SN - 978-94-010-6306-7 SP - 51 EP - 61 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Hoffschmidt, Bernhard A1 - Faber, Christian T1 - Lighthouse project for North-Rhine Westfalia - Solar thermal R & D Power Planet in Jülich T2 - Energy security, climate change and sustainable development / ed. Jyotirmay Mathur ... Y1 - 2007 SN - 81-88342-81-5 SP - 101 EP - 116 PB - Anamaya Publ. CY - New Delhi ER - TY - CHAP A1 - Kroker, Jan A1 - Hoffschmidt, Bernhard A1 - Schwarzer, Klemens A1 - Späte, Frank T1 - PTC 1000 modular parabolic trough collector T2 - Process heat collectors : state of the art within task 33/IV ; IEA SHC-Task 33 and SolarPACES-Task IV: Solar heat for industrial processes : Förderkennzeichen BMBF 0329273A / Solar Heating and Cooling Executive Committee of the International Energy Agency (IEA) ; ed. Werner Weiss Y1 - 2008 SP - 45 EP - 46 PB - AEE INTEC CY - Gleisdorf ER - TY - CHAP A1 - Mertens, Josef ED - Sobieczky, H. T1 - Required aerodynamic technologies T2 - New design concepts for high speed air transport. - (Courses and lectures / International Centre for Mechanical Sciences ; 366) N2 - In the preceeding chapters on “Son of Concorde, a Technology Challenge” and “Aerodynamic Multipoint Design Challenge” it was explained, that a well balanced contribution of new technologies in all major disciplines is required for realisation of a new Supersonic Commercial Transport (SCT). One of these technologies - usually one of the most important for aircraft-is aerodynamics. Here, the required “pure” aerodynamic technologies are specified in more detail, according to our present knowledge. Increasing insight into the problems may change the balance of importance of the individual technologies and may require some more contributions. We must never confine our knowledge to the knowledge base of an expert at a given time, but must stay open for new insights. KW - Mach Number KW - Wind Tunnel KW - Supersonic Flow KW - Pitching Moment KW - Wave Drag Y1 - 1997 SN - 3-2118-2815-X U6 - https://doi.org/10.1007/978-3-7091-2658-5_5 SP - 69 EP - 96 PB - Springer CY - Wien [u.a.] ER - TY - CHAP A1 - Mertens, Josef ED - Sobieczky, H. T1 - Certification of supersonic civil transports T2 - New design concepts for high speed air transport. - (Courses and lectures / International Centre for Mechanical Sciences ; 366) N2 - Since certification of Concorde new certification standards were introduced including many new regulations to improve flight safety. Most of these standards are to prevent severe accidents in the future which happened in the past (here: after Concorde’s certification). A new SCT has to fulfill these standards, although Concorde had none of these accidents. But accidents - although they sometimes occurred only for a specific aircraft type - have to be avoided for any (new) aircraft. Because of existing aircraft without typical accident types having demonstrated their reliability, they are allowed to go on based on their old certification; although sometimes new rules prevent accident types which are not connected to specific aircraft types - like e.g. evacuation rules. Anyway, Concorde is allowed to fly based on its old certification, and hopefully in the future will fly as safely as in the past. But a new SCT has to fulfill updated rules like any other aircraft, and it has to be “just another aircraft” [75]. KW - Noise Exposure KW - Evacuation Rule KW - Severe Accident KW - Certification Rule KW - Thermal Fatigue Testing Y1 - 1997 SN - 3-2118-2815-X U6 - https://doi.org/10.1007/978-3-7091-2658-5_6 SP - 97 EP - 103 PB - Springer CY - Wien [u.a.] ER -