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  • Untersuchung der akustischen Emission bei Bruchvorgängen in Salzgesteinen. (Investigation of acoustic emission of failure process in salt rocks)
  • Emission acoustique ; Evaporite ; Expérimentation ; Géographie physique ; Géophysique ; Mécanique des roches ; Roche ; Technique de recherche
  • Following to a consideration on general problems of acoustic emission it is discussed, if it is possible to predict the failure moment of salt rocks under uniaxial loading. For this reason amplitudes and impulse rates of acoustic emission from
  • Acoustic emissions from two landslip areas in South Wales
  • Significant acoustic emissions have been recorded from two landslide sites, both subsequent to a major failure (Pantteg) and during continuous slow movement (Glynrhigos). Four distinct types of pedogenic AE have been recognised. The effects
  • Feasibility of ice segregation location by acoustic emission detection : A laboratory test in gneiss
  • The AA. report results from a 3 month freezing experiment taht aimed to reproduce ice-lens growth at the interface between the active layer and permafrost in a 15 cm cube of hard, intact rock (Arolla gneiss). Monitoring of acoustic emissions (AEs
  • Acoustic facies and seabed features of the mixed carbonate-siliciclastic deposits of the last eustatic cycle in the La Maddalena Archipelago (North Sardinia, Italy)
  • A high-resolution Chirp acoustic survey of 250 nautical miles performed in the La Maddalena Archipelago provided a scheme of the acoustic facies of the recentmost sediments and a frame of the large-scale bedforms linked to the last eustatic cycle
  • that characterize its channels. Five main acoustic facies have been recognized and mapped. Due to the good coherence with the sediment texture map of the area, an interpretation of the acoustic facies in sedimentary terms is presented. - (NF)
  • Problems in the calibration of an acoustic device for the observation of bedload transport
  • the necessary continuous or frequent record of variations at a single section. Acoustic techniques have the potential to overcome this deficiency, but their application has been very limited. Some of the problems of calibrating an acoustic device in the field
  • Higher frequency acoustic measurements of swash processes
  • Instrumentation is described here which measures the three-dimensional, nearbed flow field using a small ultrasonic current meter and the corresponding gravel transport using an acoustic probe to monitor self-generated noise. Laboratory flume
  • calibration of the probe confirmed the theoretical dependence of the local acoustic energy level on the bedload transport rate. A series of high frequency measurements in the swash zones on the beach at Chichester Harbow are described.
  • Acoustic teledetection of shelf bedforms and their meaning for the sediment dynamics in Progress in Belgian oceanographic research.
  • Acoustic tracking of Ocean-dumped Sewage Sludge
  • of a sufficient empirical basis, contrasting results from acoustic emission studies, varying strength properties of different rock types, lack of data on actual strain resulting from short-term temperature variations, and lack of notable long-term weathering
  • Investigating the transport dynamics and the properties of bedload material with a hydro-acoustic measuring system
  • The aim of this presentation is the introduction of the preparatory work for the implementation of a hydro-acoustic measuring system allowing the registration and recording of the bedload transport in real time. The signals were recorded by means
  • Quantitative acoustic sounding from the top of a steep mountain
  • Atmospheric accoustics near the ground : a note
  • Three-dimensional measurement of river channel flow processes using acoustic doppler velocimetry
  • This paper describes and assesses : 1) the use of a new instrument for the determination of three-dimensional flow velocities in natural rivers, the acoustic Doppler velocimeter (ADV); and 2) a method for positioning and orienting such measurements
  • Acoustic Doppler current profiler measurments in coastal and estuarine environments : examples from the Tay Estuary, Scotland
  • Acoustic Doppler current profilers (ADCPs) provide a means to measure the components of water current velocities in three dimensions. Using examples of ADCP datasets acquired from the macrotidal Tay Estuary, eastern Scotland, the principles of field
  • Measuring flow velocity and sediment transport with an acoustic Doppler current profiler
  • The aim of this paper is to review and evaluate an acoustic Doppler current profiler (aDep) for measurements of flow velocity, bed load and suspended load in fluvial and lacustrine environments. Examples are provided from the Fraser Estuary
  • Measuring water velocity in highly turbulent flows : field tests of an electromagnetic current meter (ECM) and an acoustic Doppler velocimeter (ADV)
  • Two field tests were completed to compare the performance of an electromagnetic current meter (ECM) with that of an acoustic Doppler velocimeter (ADV) in gravel-bed rivers. Research was particularly motivated by the need to measure flow properties
  • Self-generated noise (SGN) is a passive acoustic technique for the measurement of bedload transport through the acoustic detection of intergranular collisions using a submerged hydrophone system. SGN is of interest because of the possibilities
  • Acoustic teledetection of sea-bottom structures in the southern bight
  • Late Quaternary sedimentation in St. George's Bay, southwest Newfoundland : acoustic stratigraphy and seabed deposits
  • Radio geopolitics : broadcasting, listening and the struggle for acoustic spaces