Refine
Year of publication
- 2024 (59)
- 2023 (237)
- 2022 (286)
- 2021 (282)
- 2020 (227)
- 2019 (377)
- 2018 (255)
- 2017 (258)
- 2016 (268)
- 2015 (301)
- 2014 (286)
- 2013 (299)
- 2012 (310)
- 2011 (323)
- 2010 (328)
- 2009 (360)
- 2008 (310)
- 2007 (312)
- 2006 (330)
- 2005 (303)
- 2004 (323)
- 2003 (254)
- 2002 (250)
- 2001 (221)
- 2000 (245)
- 1999 (236)
- 1998 (242)
- 1997 (220)
- 1996 (202)
- 1995 (192)
- 1994 (174)
- 1993 (154)
- 1992 (144)
- 1991 (100)
- 1990 (108)
- 1989 (111)
- 1988 (104)
- 1987 (105)
- 1986 (81)
- 1985 (84)
- 1984 (75)
- 1983 (70)
- 1982 (57)
- 1981 (54)
- 1980 (61)
- 1979 (58)
- 1978 (52)
- 1977 (32)
- 1976 (30)
- 1975 (28)
- 1974 (17)
- 1973 (12)
- 1972 (17)
- 1971 (11)
- 1970 (2)
- 1969 (2)
- 1968 (2)
- 1967 (1)
- 1963 (1)
- 1925 (1)
Document Type
- Article (5586)
- Conference Proceeding (1620)
- Book (1078)
- Part of a Book (548)
- Bachelor Thesis (297)
- Patent (172)
- Report (100)
- Doctoral Thesis (78)
- Other (77)
- Administrative publication (76)
- Part of Periodical (63)
- Lecture (30)
- Master's Thesis (20)
- Contribution to a Periodical (19)
- Review (17)
- Diploma Thesis (15)
- Working Paper (13)
- Course Material (9)
- Talk (7)
- Study Thesis (5)
Language
- German (5012)
- English (4801)
- Russian (14)
- Portuguese (6)
- Multiple languages (5)
- Spanish (3)
- nld (2)
- Italien (1)
Keywords
- Amtliche Mitteilung (71)
- Bachelor (33)
- Aachen University of Applied Sciences (31)
- Master (31)
- Prüfungsordnung (31)
- Bauingenieurwesen (30)
- Lesbare Fassung (28)
- Biosensor (25)
- Fachhochschule Aachen (23)
- Illustration (21)
- Studien- und Prüfungsordnung (21)
- Aachen / Fachhochschule Aachen (20)
- Änderungsordnung (20)
- Blitzschutz (18)
- Corporate Design (17)
- Elektromobilität (17)
- CAD (16)
- Finite-Elemente-Methode (16)
- Fotografie (16)
- civil engineering (14)
Institute
- Fachbereich Medizintechnik und Technomathematik (2052)
- Fachbereich Elektrotechnik und Informationstechnik (1150)
- Fachbereich Wirtschaftswissenschaften (1138)
- Fachbereich Energietechnik (1104)
- Fachbereich Maschinenbau und Mechatronik (866)
- Fachbereich Chemie und Biotechnologie (847)
- Fachbereich Luft- und Raumfahrttechnik (776)
- Fachbereich Bauingenieurwesen (705)
- IfB - Institut für Bioengineering (686)
- INB - Institut für Nano- und Biotechnologien (613)
- Fachbereich Gestaltung (484)
- Solar-Institut Jülich (339)
- Fachbereich Architektur (174)
- FH Aachen (153)
- ECSM European Center for Sustainable Mobility (112)
- ZHQ - Bereich Hochschuldidaktik und Evaluation (74)
- MASKOR Institut für Mobile Autonome Systeme und Kognitive Robotik (71)
- Nowum-Energy (70)
- Institut fuer Angewandte Polymerchemie (32)
- Sonstiges (24)
468 Scatter dose determination at the eye lens during a mask based whole brain radiotherapy (WBRT)
(2005)
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.
Soft Materials in Technology and Biology – Characteristics, Properties, and Parameter Identification
(2008)
Markierungsfreie DNA-Detektion mit Silizium-Feldeffekt-Sensoren – Messeffekte oder Artefakte?
(2007)