@inproceedings{BeckerEggertHeddieretal.2012,
  author    = {Becker, J{\"o}rg and Eggert, Mathias and Heddier, Marcel and Knackstedt, Ralf},
  title     = {Merging Conceptual Modeling and Law for Legally Compliant Information Systems Design - A Framework-Based Research Agenda},
  series = {45th Hawaii International Conference on System Sciences 2012},
  booktitle = {45th Hawaii International Conference on System Sciences 2012},
  isbn      = {978-0-7695-4525-7},
  doi       = {10.1109/HICSS.2012.428},
  pages     = {5241 -- 5248},
  year      = {2012},
  language  = {en}
}
@inproceedings{BeckerEggertSchwittay2012,
  author    = {Becker, J{\"o}rg and Eggert, Mathias and Schwittay, Sebastian},
  title     = {How to Evaluate the Practical Relevance of Business Process Compliance Checking Approaches?},
  series = {Multikonferenz Wirtschaftsinformatik 2012 - Tagungsband der MKWI 2012},
  booktitle = {Multikonferenz Wirtschaftsinformatik 2012 - Tagungsband der MKWI 2012},
  editor    = {Mattfeld, Dirk Christian},
  publisher = {Institut f{\"u}r Wirtschaftsinformatik},
  address   = {Braunschweig},
  url       = {http://nbn-resolving.de/urn:nbn:de:gbv:084-13011115376},
  pages     = {849 -- 862},
  year      = {2012},
  language  = {en}
}
@incollection{BorggrafeOhndorfDachwaldetal.2012,
  author    = {Borggrafe, Andreas and Ohndorf, Andreas and Dachwald, Bernd and Seboldt, Wolfgang},
  title     = {Analysis of interplanetary solar sail trajectories with attitude dynamics},
  series = {Dynamics and Control of Space Systems 2012},
  booktitle = {Dynamics and Control of Space Systems 2012},
  publisher = {Univelt Inc},
  address   = {San Diego},
  isbn      = {978-0-87703-587-9},
  pages     = {1553 -- 1569},
  year      = {2012},
  abstract  = {We present a new approach to the problem of optimal control of solar sails for low-thrust trajectory optimization. The objective was to find the required control torque magnitudes in order to steer a solar sail in interplanetary space. A new steering strategy, controlling the solar sail with generic torques applied about the spacecraft body axes, is integrated into the existing low-thrust trajectory optimization software InTrance. This software combines artificial neural networks and evolutionary algorithms to find steering strategies close to the global optimum without an initial guess. Furthermore, we implement a three rotational degree-of-freedom rigid-body attitude dynamics model to represent the solar sail in space. Two interplanetary transfers to Mars and Neptune are chosen to represent typical future solar sail mission scenarios. The results found with the new steering strategy are compared to the existing reference trajectories without attitude dynamics. The resulting control torques required to accomplish the missions are investigated, as they pose the primary requirements to a real on-board attitude control system.},
  language  = {en}
}
@article{HerzwurmKramsPietschetal.2012,
  author    = {Herzwurm, Georg and Krams, Benedikt and Pietsch, Wolfram and Schockert, Sixten},
  title     = {Report from the 3rd international workshop on requirements prioritization for customer oriented software development (RePriCo'12)},
  series = {ACM SIGSOFT Software Engineering Notes},
  volume    = {37},
  journal   = {ACM SIGSOFT Software Engineering Notes},
  number    = {4},
  publisher = {Association for Computing Machinery},
  address   = {New York},
  issn      = {0163-5948},
  doi       = {10.1145/2237796.2237817},
  pages     = {32 -- 34},
  year      = {2012},
  abstract  = {Prioritization is an essential task within requirements engineering to cope with complexity and to establish focus properly. The 3rd Workshop on Requirements Prioritization for customer oriented Software Development (RePriCo'12) focused on requirements prioritization and adjacent themes in the context of customer oriented development of bespoke and standard software. Five submissions have been accepted for the proceedings and for presentation. The report summarizes and points out key findings.},
  language  = {en}
}
@misc{LindelGreiserWaxmanetal.2012,
  author    = {Lindel, Tomasz Dawid and Greiser, Andreas and Waxman, Patrick and Dietterle, Martin and Seifert, Frank and Fontius, Ulrich and Renz, Wolfgang and Dieringer, Matthias A. and Frauenrath, Tobias and Schulz-Menger, Jeanette and Niendorf, Thoralf and Ittermann, Bernd},
  title     = {Cardiac CINE MRI at 7 T using a transmit array},
  series = {2012 ISMRM Annual Meeting Proceedings},
  journal   = {2012 ISMRM Annual Meeting Proceedings},
  issn      = {1545-4428},
  year      = {2012},
  abstract  = {With its need for high SNR and short acquisition times, Cardiac MRI (CMR) is an intriguing target application for ultrahigh field MRI. Due to the sheer size of the upper torso, however, the known RF issues of 7T MRI are also most prominent in CMR. Recent years brought substantial progress but the full potential of the ultrahigh field for CMR is yet to be exploited. Parallel transmission (pTx) is a promising approach in this context and several groups have already reported B1 shimming for 7T CMR. In such a static pTx application amplitudes and phases of all Tx channels are adjusted individually but otherwise imaging techniques established in current clinical practice 1.5 T and 3 T are applied. More advanced forms of pTx as spatially selective excitation (SSE) using Transmit SENSE promise additional benefits like faster imaging with reduced fields of view or improved SAR control. SSE requires the full dynamic capabilities of pTx, however, and for the majority of today's implemented pTx hardware the internal synchronization of the Tx array does not easily permit external triggering as needed for CMR. Here we report a software solution to this problem and demonstrate the feasibility of CINE CMR at 7 T using a Tx array.},
  language  = {en}
}
@incollection{NiendorfWinterFrauenrath2012,
  author    = {Niendorf, Thoralf and Winter, Lukas and Frauenrath, Tobias},
  title     = {Electrocardiogram in an MRI environment: Clinical needs, practical considerations, safety implications, technical solutions and fFuture directions},
  series = {Advances in Electrocardiograms - Methods and Analysis},
  booktitle = {Advances in Electrocardiograms - Methods and Analysis},
  editor    = {Millis, Richard},
  publisher = {IntechOpen},
  address   = {London},
  isbn      = {978-953-307-923-3 (print)},
  doi       = {10.5772/24340},
  pages     = {309 -- 324},
  year      = {2012},
  language  = {en}
}
@misc{FrauenrathPfeifferHezeletal.2012,
  author    = {Frauenrath, Tobias and Pfeiffer, Harald and Hezel, Fabian and Dieringer, Matthias A. and Winter, Lukas and Gr{\"a}ßl, Andreas and Santoro, Davide and {\"O}zerdem, Celal and Renz, Wolfgang and Greiser, Andreas and Niendorf, Thoralf},
  title     = {Lessons learned from cardiac MRI at 7.0 T: LV function assessment at 3.0 T using local multi-channel transceiver coil arrays},
  series = {2012 ISMRM Annual Meeting Proceedings},
  journal   = {2012 ISMRM Annual Meeting Proceedings},
  issn      = {1545-4428},
  year      = {2012},
  abstract  = {Cardiac MR (CMR) is of proven clinical value but also an area of vigorous ongoing research since image quality is not always exclusively defined by signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Recent developments of CMR at 7.0 T have been driven by pioneering explorations into novel multichannel transmit and receive coil array technology to tackle the challenges B1+-field inhomogeneities, to offset specific-absorption rate (SAR) constraints and to reduce banding artifacts in SSFP imaging. For this study, recognition of the benefits and performance of local surface Tx/Rx-array structures recently established at 7.0 T inspired migration to 3.0 T, where RF inhomogeneities and SAR limitations encountered in routine clinical CMR, though somewhat reduced versus the 7.0 T situation, remain significant. For all these reasons, this study was designed to build and examine the feasibility of a local four channel Tx/Rx cardiac coil array for anatomical and functional cardiac imaging at 3.0 T. For comparison, a homebuilt 4 channel Rx cardiac coil array exhibiting the same geometry as the Tx/Rx coil and a Rx surface coil array were used.},
  language  = {en}
}
@misc{FrauenrathFuchsHezeletal.2012,
  author    = {Frauenrath, Tobias and Fuchs, Katharina and Hezel, Fabian and Dieringer, Matthias A. and Rieger, Jan and Niendorf, Thoralf},
  title     = {Improved cardiac triggering by combining multiple physiological signals: a cardiac MR feasibility study at 7.0 T},
  series = {2012 ISMRM Annual Meeting Proceedings},
  journal   = {2012 ISMRM Annual Meeting Proceedings},
  issn      = {1545-4428},
  year      = {2012},
  abstract  = {In current clinical cardiovascular MR (CMR) practice cardiac motion is commonly dealt with using ECG based synchronization. However, ECG is corrupted by magneto-hydrodynamic (MHD) effects in magnetic fields. This leads to artifacts in the ECG trace and evokes severe T-wave elevations, which might be misinterpreted as R-waves resulting in erroneous triggering. At (ultra)high field strengths, the propensity of ECG recordings to MHD effects is further pronounced. Pulse oximetry (POX) being inherently sensitive to blood oxygenation provides an alternative approach for cardiac gating. However, due to the travel time of the blood the peak of maximum oxygenation and hence the trigger is delayed by approx. 300 ms with respect to the ECG's R-wave. Also the peak of maximum oxygenation shows a jitter of up to 65 ms. Alternative triggering approaches include acoustic cardiac triggering (ACT). In current clinical practice cardiac gating / triggering commonly relies on using single physiological signals only. Realizing this limitation this study proposes a combined triggering approach which exploits multiple physiological signals including ECG, POX or ACT to track cardiac activity. The feasibility of the coupled approach is examined for LV function assessment at 7.0 T. For this purpose, breath-held 2D-CINE imaging in conjunction with cardiac synchronization was performed paralleled by real time logging of physiological waveforms to track (mis)synchronization between the cardiac cycle and data acquisition. Combinations of the ECG, POX and ACT signals were evaluated and processed in real time to facilitate reliable trigger information.},
  language  = {en}
}
@misc{TkachenkovonKnobelsdorffBrenkenhoffKleindienstetal.2012,
  author    = {Tkachenko, Valeriy and von Knobelsdorff-Brenkenhoff, Florian and Kleindienst, Denise and Winter, Lukas and Rieger, Jan and Frauenrath, Tobias and Dieringer, Matthias A. and Santoro, Davide and Niendorf, Thoralf and Schulz-Menger, Jeanette},
  title     = {Cardiovasular MR at 7Tesla: assessment of the right ventricle},
  series = {2012 ISMRM Annual Meeting Proceedings},
  journal   = {2012 ISMRM Annual Meeting Proceedings},
  issn      = {1545-4428},
  year      = {2012},
  abstract  = {The assessment of the right ventricle (RV) is a challenge in today's cardiology, but of growing clinical impact regarding patient prognosis in different cardiac diseases. The detection and differentiation of small wall motion abnormalities may help to enhance the differentiation of cardiomyopathies including Arrhythmogenic Rightventricular Cardiomyopathy. Cardiovascular magnetic resonance (CMR) at 1.5T is the accepted gold standard for RV quantification. The higher spatial resolution achievable at ultrahigh field strength (UHF) offers the potential to gain new insights into the structure and function of the RV. To approach this goal accurate RV chamber quantification at 7T has to be proven. Consequently this study examines the feasibility of assessment of RV dimensions and function at 7T using improved spatial resolution enabled by the intrinsic sensitivity gain of UHF CMR. For this purpose, a dedicated 16 channel TX/RX RF coil array is used together with 2D CINE fast gradient echo (FGRE) imaging. For comparison RV chamber quantification is conducted at 1.5T using a SSFP based state of the art clinical protocol.},
  language  = {en}
}
@misc{GraesslRenzHezeletal.2012,
  author    = {Gr{\"a}ßl, Andreas and Renz, Wolfgang and Hezel, Fabian and Frauenrath, Tobias and Pfeiffer, Harald and Hoffmann, Werner and Kellmann, Peter and Martin, Conrad and Niendorf, Thoralf},
  title     = {Design, evaluation and application of a modular 32 channel transmit/receive surface coil array for cardiac MRI at 7T},
  series = {2012 ISMRM Annual Meeting Proceedings},
  journal   = {2012 ISMRM Annual Meeting Proceedings},
  issn      = {1545-4428},
  year      = {2012},
  abstract  = {Cardiac MR (CMR) at ultrahigh (≥7.0 T) fields is regarded as one of the most challenging MRI applications. At 7.0 T image quality is not always exclusively defined by signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). Detrimental effects bear the potential to spoil the signal-to-noise (SNR) and contrast-to-noise (CNR) benefits of cardiac MR (CMR) at 7.0 T. B₁⁺-inhomogeneities and signal voids represent the main challenges. Various pioneering coil concepts have been proposed to tackle these issues, enabling cardiac MRI at 7.0 T. This includes a trend towards an ever larger number of transmit and receive channels. This approach affords multi-dimensional B₁⁺ modulations to improve B₁⁺ shimming performance and to enhance RF efficiency. Also, parallel imaging benefits from a high number of receive channels enabling two-dimensional acceleration. Realizing the limitations of existing coil designs tailored for UHF CMR and recognizing the opportunities of a many element TX/RX channel architecture this work proposes a modular, two dimensional 32-channel transmit and receive array using loop elements and examines its efficacy for enhanced B¹+ homogeneity and improved parallel imaging performance.},
  language  = {en}
}