Ein hochgenaues Längenmeßgerät zur Absolutbestimmung der Fortpflanzungsgeschwindigkeit von Ultraschallwellen in Wasser

Es wird ein Verfahren beschrieben, wie aus der Messung von Frequenz und Wellenlänge von Schallwellen die Schallgeschwindigkeit bestimmt werden kann. Die Messung der Wellenlänge geschieht mit Hilfe von optischen Interferometern, deren Aufbau und Konstruktion näher beschrieben wird. The paper describes a method for absolute determination of velocity of sound in water by measuring wavelength and frequency of acoustical sinewaves. The measurement of wave-length is done by optical interferometers. The arrangement of these interferometers and the construction of themselves are described in this paper

Dokumentation über das aufgegebene Kalksteinlager im Lichtenauer Ortsteil Ottendorf

Erkenntnisstand Januar 2006 1. Aktualisierung, August 201

A ship rain gauge for use in high wind speeds.

A ship rain gauge has been developed that can be used under high wind speeds such as those experienced by ships at sea. The instrument has an improved aerodynamic design and an additional lateral collecting surface, which is effective especially with high wind speeds. The ship rain gauge has been calibrated at sea against a specially designed optical disdrometer. An accuracy of 2%–3% has been obtained for 6-hourly sums. The ship rain gauge has also successfully been tested at a test site of the German Weather Service and presently is used on research vessels and voluntary observing ship