@inproceedings{15338,
  abstract     = {{There are a couple of acoustic systems that are well suited for continuous and reliable concentration measurement of liquids, but the reliability is a great challenge: Most systems determine the amplitude ratio of deflected ultrasound bursts at different boundaries as well as the sound velocity of the liquid in order to calculate its acoustic impedance and therewith its density. The problem is the sensitivity of variations of reference material properties as well as abrasion or soiling of the boundaries. This contribution is about a new model-based method that uses the whole surface of an acoustic waveguide as reference boundary. On the one hand the integral over a large boundary decreases influence of small boundary defects. On the other hand it is possible to analyze different modes of sound in the fluid. This redundancy can be used to increase reliability. The decomposition of the received signal in its modal components by means of principle component analysis will be discussed in detail. It will be shown that it is possible to determine the amplitudes of each mode by means of one measured signal at the end of the waveguide, even if the transducer and the electronic components are of very simple kind}},
  author       = {{Rautenberg, Jens and Henning, Bernd}},
  booktitle    = {{Proceedings of the International Congress on Ultrasonics}},
  title        = {{{Measurement of the acoustic properties of highly absorbing synthetic polymers}}},
  year         = {{2007}},
}

@inproceedings{15339,
  abstract     = {{Continuous and reliable concentration measurement of liquids still is a great challenge as the sensor systems have to meet high industrial requirements. Apart from chemical sensors there are a couple of acoustic systems [1] that are well suited for a lot of industrial applications. Most of them determine the amplitude ratio of deflected ultrasound bursts at different boundaries as well as the sound velocity of the liquid in order to calculate its acoustic impedance and therewith its density. The advantages of acoustic sensors are their robustness and their fast response. Their disadvantages are sensitivity against variations of the reference material properties as well as abrasion or soiling of the boundaries. This contribution is about a new model-based method that uses the whole surface of an acoustic waveguide as reference boundary: It has turned out that the principal components of a signal at the end of the waveguide can be assigned to the different propagative acoustic modes (Fig. 1). Therefore it is necessary to use different simulation tools, e.g. FEM and modal analysis (Fig. 2). With this it is possible to determine the amplitudes of each mode by means of one measured signal at the end of the waveguide and Gauss Algorithm even if the transducer is of very simple kind [2]. Therewith it is possible to get redundant information -- one amplitude for each mode -- for the liquid impedance. In addition to that it is possible to generate an acoustic reference signal without information about the liquid impedance but dissipation if we use the fundamental mode. The different signal amplitudes and a model of acoustic wave propagation [2, 3] offer the possibility to distinguish between dissipation in the liquid and attenuation due to the impedance relations. Moreover, if there are enough analysable amplitudes available, variations of the reference material properties can be determined.}},
  author       = {{Rautenberg, Jens and Henning, Bernd}},
  isbn         = {{978-3-9810993-2-4}},
  location     = {{Nürnberg}},
  pages        = {{87--92}},
  title        = {{{New approach for the reliable measurement of acoustic impedance of liquids in an acoustic waveguide}}},
  volume       = {{II}},
  year         = {{2007}},
}

@inproceedings{15340,
  abstract     = {{There are a couple of acoustic systems that are well suited for continuous and reliable concentration measurement of liquids, but the reliability is a great challenge: Most systems determine the amplitude ratio of deflected ultrasound bursts at different boundaries as well as the sound velocity of the liquid in order to calculate its acoustic impedance and therewith its density. The problem is the sensitivity of variations of reference material properties as well as abrasion or soiling of the boundaries. This contribution is about a new model-based method that uses the whole surface of an acoustic waveguide as reference boundary. On the one hand the integral over a large boundary decreases influence of small boundary defects. On the other hand it is possible to analyze different modes of sound in the fluid. This redundancy can be used to increase reliability. The decomposition of the received signal in its modal components by means of principle component analysis will be discussed in detail. It will be shown that it is possible to determine the amplitudes of each mode by means of one measured signal at the end of the waveguide, even if the transducer and the electronic components are of very simple kind.}},
  author       = {{Rautenberg, Jens and Henning, Bernd}},
  booktitle    = {{Proceedings of the International Congress on Ultrasonics}},
  title        = {{{Separation of mode-specific signals in a fluid-filled circular waveguide}}},
  year         = {{2007}},
}

@misc{15341,
  author       = {{Sonnenberg, Hans-Michael and Schmidt-Schoenian, Axel and Rautenberg, Jens and Unverzagt, Carsten and Kehl, Romina and Henning, Bernd}},
  title        = {{{Ultraschallzähler}}},
  year         = {{2007}},
}

@inproceedings{15342,
  abstract     = {{In der Ultraschallmesstechnik ist der Einsatz des Impuls-Echoverfahrens verbreitet. Wird nur ein Ultraschallwandler eingesetzt, benötigt man für das sequentielle Senden und Empfangen einen Sende-/Empfangsumschalter. Häufig werden aber nicht nur Impulse gesendet, sondern auch sogenannte Bursts, die aus mehreren Wellenzügen bestehen. Die während des Sendebetriebs empfangenen Ultraschallwellen, die z. B. durch Reflexionen von nahe gelegenen Hindernissen entstehen, können bei diesen umschaltenden Systemen nicht ausgewertet werden.
In diesem Beitrag wird eine Sensor-Interface-Elektronik vorgestellt, die das gleichzeitige Senden und Empfangen von Ultraschallsignalen mit nur einem Ultraschallwandler erlaubt. Die dazu erforderliche Trennung von Sende- und Empfangssignal wird durch einen Richtkoppler ermöglicht, der mit vergleichsweise geringem technischem Aufwand aus Breitbandübertragern aufgebaut ist. Eine geeignete Dimensionierung für die verkoppelten Übertrager wurde durch die Analyse der zugehörigen Streumatrix dieses Aufbaus gefunden. Die Arbeitsweise sowie die Bedeutung der Anpassung der Tore des Richtkopplers wird anhand der Ankopplung verschiedener Medien an den Wandler erläutert. Die angekoppelte akustische Last beeinflusst dabei auch die elektrischen Eigenschaften des Sensors.
Durch den Einsatz dieser Sensorelektronik wird es möglich, Reflexionen in unmittelbarer Nähe der Sensoroberfläche aufzunehmen, ohne dass z. B. Vorlaufkörper eingesetzt werden müssen. Möglichkeiten zur selbsttätigen Abstimmung der Sensorelektronik auf den angeschlossenen Ultraschallwandler bzw. dessen Parameteränderungen werden diskutiert.}},
  author       = {{Vössing, Torsten and Rautenberg, Jens and Henning, Bernd}},
  booktitle    = {{Fortschritte der Akustik}},
  editor       = {{Mehra, Schew-Ram}},
  isbn         = {{9783980865937}},
  publisher    = {{Dt. Ges. für Akustik}},
  title        = {{{Sensorelektronik zur Bestimmung von Reflexionen sensoroberflächennaher Schichten}}},
  year         = {{2007}},
}

@inproceedings{15343,
  abstract     = {{In der Ultraschallmesstechnik ist der Einsatz des Impuls-Echoverfahrens verbreitet. Wird nur ein Ultraschallwandler eingesetzt, benötigt man für das sequentielle Senden und Empfangen einen Sende-/Empfangsumschalter. Häufig werden aber nicht nur Impulse gesendet, sondern auch sogenannte Bursts, die aus mehreren Wellenzügen bestehen. Die während des Sendebetriebs empfangenen Ultraschallwellen, die z. B. durch Reflexionen von nahe gelegenen Hindernissen entstehen, können bei diesen umschaltenden Systemen nicht ausgewertet werden.
In diesem Beitrag wird eine Sensor-Interface-Elektronik vorgestellt, die das gleichzeitige Senden und Empfangen von Ultraschallsignalen mit nur einem Ultraschallwandler erlaubt. Die dazu erforderliche Trennung von Sende- und Empfangssignal wird durch einen Richtkoppler ermöglicht, der mit vergleichsweise geringem technischem Aufwand aus Breitbandübertragern aufgebaut ist. Eine geeignete Dimensionierung für die verkoppelten Übertrager wurde durch die Analyse der zugehörigen Streumatrix dieses Aufbaus gefunden. Die Arbeitsweise sowie die Bedeutung der Anpassung der Tore des Richtkopplers wird anhand der Ankopplung verschiedener Medien an den Wandler erläutert. Die angekoppelte akustische Last beeinflusst dabei auch die elektrischen Eigenschaften des Sensors.
Durch den Einsatz dieser Sensorelektronik wird es möglich, Reflexionen in unmittelbarer Nähe der Sensoroberfläche aufzunehmen, ohne dass z. B. Vorlaufkörper eingesetzt werden müssen. Möglichkeiten zur selbsttätigen Abstimmung der Sensorelektronik auf den angeschlossenen Ultraschallwandler bzw. dessen Parameteränderungen werden diskutiert.}},
  author       = {{Vössing, Torsten and Rautenberg, Jens and Henning, Bernd}},
  booktitle    = {{Fortschritte der Akustik}},
  editor       = {{Mehra, Schew-Ram}},
  isbn         = {{9783980865937}},
  location     = {{Stuttgar}},
  publisher    = {{Dt. Ges. für Akustik}},
  title        = {{{Sensorelektronik zur Bestimmung von Reflexionen sensoroberflächennaher Schichten}}},
  year         = {{2007}},
}

@inproceedings{15344,
  abstract     = {{In many applications ultrasonic transducers are used for transmitting and receiving ultrasonic waves. Ultrasonic sensor systems meet the practical requirements of industrial applications quite well. Typical sensor applications are for example the measurement of distance and thickness. Especially if only one ultrasonic transceiver and the well-known pulse-echo-method are used, the sensor electronics has to switch from transmitting to receiving mode. This is one of the most limiting properties because the probe can not receive echoes from nearby obstacles or thin material layers. This contribution deals with the development of an electronic interface circuit for ultrasonic sensors allowing transmitting and receiving of acoustic signals simultaneously. There are already several methods to separate the transmitted from the received signal for instance the well-known circulator in the telephone, the differential transformer mentioned by Bradfield [1] or a directional coupler [2]. The directional coupler consists of two broadband transformers linked with each other in such a way that it equally distributes the input power at port one to the third and fourth port, while port two is isolated. This circuit is also known as 3 dB directional coupler and makes it possible to get reference echoes directly from the interface between the sensor and the medium of interest. Several reflectors or multiple sound paths such as used in ultrasonic density measurement systems are unnecessary [3].}},
  author       = {{Vössing, Torsten and Rautenberg, Jens and Kehl, Romina and Henning, Bernd}},
  isbn         = {{978-3-9810993-2-4}},
  location     = {{Nuremberg}},
  title        = {{{Simultaneous transmitting and receiving with ultrasonic sensors}}},
  year         = {{2007}},
}

@inproceedings{15345,
  abstract     = {{In this contribution the application of a directional coupler for analysing reference reflections from thin layers in ultrasonic measurement of the characteristic acoustic impedance is presented. In a prior work ([2]) it was shown, that a directional coupler can be used in combination with an ultrasonic transducer to get reflections from layers that are very close to the transducers surface. Since the directional coupler provides the opportunity to send and receive signals at the same time, these layers can be very thin ({\textless} 1 mm). Reflections that arrive at the transducer during the sending process can be analysed because the directional coupler separates the receiving signal from the input signal of the transducer. When only one transducer is used to measure the acoustic impedance of a liquid the reflections from the thin layer reach the transducer after a very short time. The reflections sum up and with the concept of reflection and transmission coefficients a relation is found between the measured amplitude and a reference amplitude which was measured before. The exciting signal could be a burst of some periods of a sinusoidal alternating voltage. The advantages of using thin layers for the described task are the small geometry that allows flexible application of the sensor and the minimisation of temperature gradients within the medium because thin layers can follow thermal fluctuations faster than thick ones. In this paper the functional principle and first achievements are presented.}},
  author       = {{Vössing, Torsten and Rautenberg, Jens and Schröder, Andreas and Henning, Bernd}},
  location     = {{Xi’An, China}},
  title        = {{{Ultrasonic measurement of the characteristic acoustic impedance using a directional coupler to analyse reference reflections from thin layers}}},
  year         = {{2007}},
}

@inproceedings{15470,
  author       = {{Domik, Gitta}},
  booktitle    = {{ACM SIGGRAPH 2007 educators program}},
  pages        = {{2}},
  title        = {{{A graduate level course on real-time medical graphics}}},
  year         = {{2007}},
}

@inproceedings{15471,
  author       = {{Fricke, H and Schwier, M and Weise, R and Elsner, A and Fricke, E and Domik, Gitta and Burchert, W}},
  booktitle    = {{Proc. of the 54th SNM Annual Meeting}},
  title        = {{{Coregistration and visualization of cardiac CT studies and dynamic PET studies using scene-graphs, direct volume rendering and 2D transfer functions}}},
  volume       = {{48}},
  year         = {{2007}},
}

@inproceedings{15691,
  author       = {{Schulte, Carsten and Knobelsdorf, Maria}},
  booktitle    = {{ICER}},
  pages        = {{27--38}},
  publisher    = {{ACM}},
  title        = {{{Attitudes towards computer science-computing experiences as a starting point and barrier to computer science}}},
  year         = {{2007}},
}

@inproceedings{15692,
  author       = {{Schulte, Carsten}},
  booktitle    = {{INFOS}},
  pages        = {{307--318}},
  publisher    = {{GI}},
  title        = {{{Lesen im Informatikunterricht}}},
  volume       = {{P-112}},
  year         = {{2007}},
}

@inproceedings{15693,
  author       = {{Schulte, Carsten and Knobelsdorf, Maria}},
  booktitle    = {{INFOS}},
  pages        = {{69--79}},
  publisher    = {{GI}},
  title        = {{{Das informatische Weltbild von Studierenden}}},
  volume       = {{P-112}},
  year         = {{2007}},
}

@inproceedings{15782,
  author       = {{Cheng, W. and Hüllermeier, Eyke and Seeger, B. and Vladimirskiy, I.}},
  booktitle    = {{In Proceedings Workshop LWA-2007, Lernen-Wissensentdeckung-Adaptivität, Halle/Saale, Germany}},
  pages        = {{141--148}},
  title        = {{{Interactive ranking of skylines using machine learning techniques}}},
  year         = {{2007}},
}

@inproceedings{15783,
  author       = {{Fober, T. and Hüllermeier, Eyke and Mernberger, M.}},
  booktitle    = {{in Proceedings 17th Workshop Computational Intelligence, Dortmund Germany}},
  editor       = {{Mikut, R. and Reischl, M.}},
  pages        = {{1--14}},
  title        = {{{Evolutionary construction of multiple graph alignments for the structural analysis of biomolecules}}},
  year         = {{2007}},
}

@inproceedings{15784,
  author       = {{Vladimirskiy, I. and Hüllermeier, Eyke and Stauch, E.}},
  booktitle    = {{In Workshop Proceedings from ICCBR-2007 7th International Conference on Case-Based Reasoning, Belfast, Northern Ireland}},
  editor       = {{Wilson, D.C. and Khemani, D.}},
  pages        = {{31--40}},
  title        = {{{Similarity search over uncertain archaeological data using a modified skyline operator}}},
  year         = {{2007}},
}

@inproceedings{14832,
  author       = {{Hüllermeier, Eyke and Fürnkranz, J.}},
  booktitle    = {{In Proceedings ECML-2007, 17th European Conference on Machine Learning, Warsawa, Poland, September 2007}},
  publisher    = {{Springer}},
  title        = {{{On minimizing the position error in label ranking}}},
  year         = {{2007}},
}

@inproceedings{14833,
  author       = {{Brinker, K. and Hüllermeier, Eyke}},
  booktitle    = {{In Proceedings ICCBR-2007, 7th International Conference on Case-Based Reasoning, Belfast, Northern Ireland}},
  editor       = {{Richter, M. and Weber, R.}},
  pages        = {{77--91}},
  publisher    = {{Springer}},
  title        = {{{Label ranking in case-based reasoning}}},
  volume       = {{4626}},
  year         = {{2007}},
}

@inproceedings{14834,
  author       = {{Beringer, J. and Hüllermeier, Eyke}},
  booktitle    = {{In Proceedings ICDM-2007, International Conference on Industrial Data Mining, Leipzig}},
  editor       = {{Perner, P.}},
  pages        = {{34--48}},
  publisher    = {{Springer}},
  title        = {{{Efficient instance-based learning on data streams}}},
  year         = {{2007}},
}

@inproceedings{14835,
  author       = {{Brinker, K. and Hüllermeier, Eyke}},
  booktitle    = {{in Proceedings IJCAI-07, 20th international Joint Conference on Artificial Intelligence, Hyerabad, India, January 2007}},
  pages        = {{701--707}},
  title        = {{{Case-based multilabel ranking}}},
  year         = {{2007}},
}