@misc{15383,
  abstract     = {{Die elektrische Impedanzmessung ist heute in einem weiten Frequenzbereich technisch möglich und wird vielfach zur Materialcharakterisierung eingesetzt. Neben den elektrischen und optischen Messverfahren verfügen aber auch gerade die akustischen Messverfahren über vorteilhafte Applikationseigenschaften wie Robustheit und geringe Wartungsanforderungen. Die zuverlässige Bestimmung der Schallkennimpedanz als eine der drei akustischen Stoffkenngrößen erweist sich aber noch heute als sehr diffizil, wie im Folgenden gezeigt wird.}},
  author       = {{Henning, Bernd}},
  title        = {{{Ultraschall-Impedanz-Spektrometrie zur Erfassung von Stoff- und Strukturgrößen}}},
  year         = {{2003}},
}

@misc{15384,
  author       = {{Auge, Jörg and Dierks, Karsten and Henning, Bernd and Prange, Stefan}},
  title        = {{{Vorrichtung zur Bestimmung des Volumens, der Oberflächenspannung und der Viskosität von Flüssigkeitstropfen}}},
  year         = {{2003}},
}

@inproceedings{15385,
  abstract     = {{One of the most widely spread measuring tasks in chemistry or food technology is the continuous determination of fill levels in liquid tanks. The aim of this paper is to present a new contactless and noninvasive measuring method based on ultrasonic time-reversal and correlation techniques. The novel method enables asserted fill levels to be identified and small deviations of them to be calculated even if the direct path from the sensor to the liquid surface is obstructed. This article will present the structure and principle of the measuring system as well as the procedure of signal processing. A simulative approach is used to demonstrate the excitation of a virtual sound source in the liquid and to show both the advantages and limits of the new technique. In addition a simplified model is developed where the solutions of the simulations are applied to.}},
  author       = {{Henning, Bernd and Rautenberg, Jens and Gulsch, Michael and Klüppel, Stefan}},
  booktitle    = {{SENSOR~Proceedings}},
  publisher    = {{AMA Service GmbH}},
  title        = {{{The Use of Time-Reversal Technology for Level Measurement in Liquid Tanks}}},
  year         = {{2003}},
}

@inproceedings{15361,
  abstract     = {{The determination of small liquid volumes and their changes over a period of time is a measuring problem with increasing importance considering the growing market of micro-systems. In this paper, experimental investigations are described which aim to observe the growth of droplets at the end of a micro channel, such as a cannula or capillary. The main focus of the work lies on the calculation of flow rates below 1 millilitre per hour. Furthermore, the potential of the measuring equipment for liquid level and surface tension measurement is described.}},
  author       = {{Auge, Jörg and Dierks, Karsten and Prange, Stefan and Henning, Bernd}},
  location     = {{Prag}},
  pages        = {{375--378}},
  title        = {{{Monitoring of droplet growth with nano-litre resolution for liquid flow rate, level or surface tension measurement}}},
  volume       = {{5-12}},
  year         = {{2002}},
}

@inproceedings{15386,
  abstract     = {{The determination of small liquid volumes and their changes over a period of time is a measuring problem with increasing importance considering the growing market of micro-systems. In this paper, experimental investigations are described which aim to observe the growth of droplets at the end of a micro channel, such as a cannula or capillary. The main focus of the work lies on the calculation of flow rates below 1 millilitre per hour. Furthermore, the potential of the measuring equipment for liquid level and surface tension measurement is described.}},
  author       = {{Auge, Jörg and Dierks, Karsten and Prange, Stefan and Henning, Bernd}},
  location     = {{Prag}},
  pages        = {{375--378}},
  title        = {{{Monitoring of droplet growth with nano-litre resolution for liquid flow rate, level or surface tension measurement}}},
  volume       = {{5-12}},
  year         = {{2002}},
}

@article{13889,
  author       = {{Puttmer, A. and Hauptmann, P. and Henning, Bernd}},
  issn         = {{0885-3010}},
  journal      = {{IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control}},
  pages        = {{85--92}},
  title        = {{{Ultrasonic density sensor for liquids}}},
  doi          = {{10.1109/58.818751}},
  year         = {{2002}},
}

@article{13890,
  author       = {{Püttmer, A and Hoppe, N and Henning, Bernd and Hauptmann, P}},
  issn         = {{0924-4247}},
  journal      = {{Sensors and Actuators A: Physical}},
  pages        = {{122--126}},
  title        = {{{Ultrasonic density sensor - analysis of errors due to thin layers of deposits on the sensor surface}}},
  doi          = {{10.1016/s0924-4247(98)00365-3}},
  year         = {{2002}},
}

@article{13812,
  author       = {{Püttmer, A. and Lucklum, R. and Henning, Bernd and Hauptmann, P.}},
  issn         = {{0924-4247}},
  journal      = {{Sensors and Actuators A: Physical}},
  pages        = {{8--12}},
  title        = {{{Improved ultrasonic density sensor with reduced diffraction influence}}},
  doi          = {{10.1016/s0924-4247(97)01720-2}},
  year         = {{2002}},
}

@inproceedings{15387,
  abstract     = {{In diesem Beitrag werden Messungen und Auswertungen der Ultraschallgeschwindigkeitsmessung zur Überwachung von Hefekultivierungen vorgestellt. Die Ultraschallgeschwindigkeit ist abhängig von Biomasse-, Glukose- und Ethanolkonzentration, aber auch von anderen Bioprozessvariablen. Um den Einfluss von Blasen auf das Signal zu reduzieren, wurde der Ultraschallsensor in einem Bypass-System eingesetzt. Es wurden Messungen sowohl im Flow- als auch Stop-Flow-Betrieb durchgeführt. Um die richtigen Informationen aus diesem unspezifischen Signal zu erhalten, wurde ein multilineares Regressionsmodell berechnet, wobei die Biomasse-, Glukose- und Ethanolkonzentration als unabhängige Variablen dienten. Ein Beispiel der Ergebnisse ist in Abbildung eins gezeigt. Es sind die Biomasse-, Glukose- und Ethanolkonzentration während einer Saccharomyces cerevisiae Kultivierung dargestellt. Die Parameter des multilinearen Regressionsmodells wurden durch Verwendung der Daten aus der dargestellten Kultivierung identifiziert. Wird dieses Modell zur Auswertung auf die Signale anderer Prozesse übertragen, ist das Ergebnis ähnlich, jedoch vergrößert sich der Fehler der Schätzung. Die Ergebnisse sowie Erfahrungen werden ausführlich in dem Beitrag diskutiert.}},
  author       = {{Cha, Y. L. and Hitzmann, Bernd and Bellgardt, Karl-Heinz and Daur, Peter-Christoph and Henning, Bernd}},
  location     = {{Leipzig}},
  pages        = {{226}},
  title        = {{{Ultraschallgeschwindigkeitsmessung zum Bioprozessmonitoring}}},
  year         = {{2001}},
}

@inproceedings{15388,
  abstract     = {{Nowadays the use of ultrasonic sensors for process control for flow, level or concentration measurement is wide spread. In this application there are high demands for a defined and stable quality of the properties of such ultrasonic sensors. For the detailed investigation and characterization of ultrasonic sensor properties an efficient PC-controlled measuring system has been developed at ifak. In this report this new high performance approach will be presented to make the vibrating ultrasonic sensor surface and also the sound field in front of acoustic sensors in liquids visible.}},
  author       = {{Henning, Bernd and Prange, Stefan and Dierks, Karsten and Daur, Peter-Christoph}},
  location     = {{Nürnberg}},
  title        = {{{Quality inspection and characterisation of ultrasonic sensor properties using a PC-controlled scanning measuring system}}},
  volume       = {{A8.2}},
  year         = {{2001}},
}

@article{15389,
  abstract     = {{Recently there has been increased demand for chemicaJ sensors measuring in-line the concentration of selected substances in complex liquids in order to guarantee a high product quality in the process industry. At present there is a great interest in acoustic sensor systems for concentration measurements. This article presents a new ultrasonic sensor system consisting of a miniaturized multi-sensor arrangement for the comprehensive acoustic characterization of liquid mixtures. The sensor system measures sound velocity, impedance coefficient, attenuation coefficient an9 temperature.}},
  author       = {{Henning, Bernd and Daur, Peter-Christoph and Prange, Stefan and Dierks, Karsten and Hauptmann, Peter}},
  journal      = {{Ultrasonics}},
  pages        = {{799--803}},
  title        = {{{In-line concentration measurement in complex liquids using ultrasonic sensors}}},
  doi          = {{10.1016/s0041-624x(99)00190-0}},
  year         = {{2000}},
}

@misc{15390,
  author       = {{Henning, Bernd and Daur, Peter-Christoph and Prange, Stefan and Dierks, Karsten}},
  pages        = {{165--172}},
  title        = {{{In-Line-Flüssigkeitsanalysator für verfahrenstechnische Prozesse}}},
  year         = {{1998}},
}

@article{13810,
  author       = {{Hauptmann, Peter and Lucklum, Ralf and Püttmer, Alf and Henning, Bernd}},
  journal      = {{Sensors and Actuators A: Physical}},
  number       = {{1-3}},
  pages        = {{32--48}},
  title        = {{{Ultrasonic sensors for process monitoring and chemical analysis state of the art and trends}}},
  doi          = {{10.1016/S0924-4247(97)01725-1}},
  volume       = {{67}},
  year         = {{1998}},
}