Making Waves - Towards a New Era of Seismic Recording Equipment

In the article the means of musical communication and their evolution are considered in the historical and analytical aspect. There are two types of communication tools: acoustic, using the airspace as a channel for transmitting encoded information, and visual, which include stage design, allowing to perceive music as a kind of theatrical performance, and musical notation, graphically fixing all the components of the musical text. As the earliest means of nonwritten communication, the oral method is put forward, a vivid example of which is folklore, often called the musical memory of generations. Other examples of oral communication are cult music, improvisation and musical meditation. It is stated that musical writing, in particular, musical notation, and later printing tools have created conditions for overcoming spatial and temporal barriers to the spread of music. The next step is the invention of technical sound recording, which opened a new era in the development of communications. Magnetic recording of the visual series made it possible to create concert films and opera films. Even greater involvement of people in the process of musical communication was facilitated by the appearance of electronic and mechanical means of recording music. The emergence of new opportunities in the field of sound dynamics control, its timbre, influenced the development of musical thinking. A new industry of "production" has emerged with the involvement of professional musicians who own modern recording equipment and specialize in the production of "artificial" musical products. This process was accompanied by the formation of a new audience of listeners who preferred recording to live sound.

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New Frontiers of Seismic Surveying in Antarctica: The Mapping of A Thin Layer at the Base of Ice Stream B (Abstract)

Annals of Glaciology ◽

10.3189/s0260305500001531 ◽

1986 ◽

Vol 8 ◽

pp. 202-202

Author(s):

Donald D. Blankenship

Keyword(s):

Thin Layer ◽

Seismic Reflection ◽

Dynamic Range ◽

Basal Layer ◽

Recording Equipment ◽

Power Requirement ◽

Large Bandwidth ◽

Ice Stream ◽

Seismic Recording ◽

Ice Stream B

The recent availability of high resolution (greater than 250 Hz) seismic recording equipment in the Antarctic field environment has allowed the acoustical mapping of a previously unobserved subglacial phenomenon. This phenomenon is a thin (less than 10 m), yet continuous, layer at the base of Ice Stream B in West Antarctica. Discovery of this layer came during the 1983–84 austral summer in a seismic reflection survey that covered approximately 10 km2 near the Upstream B field camp (83°31’S, 138°05’W). Although analysis of the seismic data is at a preliminary stage, there is the possibility that this feature could be a basal “lubricating” layer; some sort of lubrication is of course necessary to explain the very large horizontal velocities of these ice streams.During the seismic reflection survey on Ice Stream B, a new digital seismic recording system, developed by the Geophysical and Polar Research Center, was used for the first time under field conditions. Resolution of such a thin layer was possible only because of the very large bandwidth (0–600 Hz) and dynamic range (84 dB) of this device; this bandwidth is about twice that possessed by commercially available seismic recorders. In addition, a new level of portability (i.e. a weight of 40 kg and a power requirement of 90 watts), which should make this device usable in virtually any Antarctic field situation, has been achieved by the application of advanced recording technologies. The portability of this digital seismic recorder, when combined with its large bandwidth and dynamic range, should result in the resolution of a whole new class of intra- and subglacial phenomena, of which the thin basal layer of Ice Stream B is the first example.

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New Frontiers of Seismic Surveying in Antarctica: The Mapping of A Thin Layer at the Base of Ice Stream B (Abstract)

Annals of Glaciology ◽

10.1017/s0260305500001531 ◽

1986 ◽

Vol 8 ◽

pp. 202

Author(s):

Donald D. Blankenship

Keyword(s):

Thin Layer ◽

Seismic Reflection ◽

Dynamic Range ◽

Basal Layer ◽

Recording Equipment ◽

Power Requirement ◽

Large Bandwidth ◽

Ice Stream ◽

Seismic Recording ◽

Ice Stream B

The recent availability of high resolution (greater than 250 Hz) seismic recording equipment in the Antarctic field environment has allowed the acoustical mapping of a previously unobserved subglacial phenomenon. This phenomenon is a thin (less than 10 m), yet continuous, layer at the base of Ice Stream B in West Antarctica. Discovery of this layer came during the 1983–84 austral summer in a seismic reflection survey that covered approximately 10 km2 near the Upstream B field camp (83°31’S, 138°05’W). Although analysis of the seismic data is at a preliminary stage, there is the possibility that this feature could be a basal “lubricating” layer; some sort of lubrication is of course necessary to explain the very large horizontal velocities of these ice streams. During the seismic reflection survey on Ice Stream B, a new digital seismic recording system, developed by the Geophysical and Polar Research Center, was used for the first time under field conditions. Resolution of such a thin layer was possible only because of the very large bandwidth (0–600 Hz) and dynamic range (84 dB) of this device; this bandwidth is about twice that possessed by commercially available seismic recorders. In addition, a new level of portability (i.e. a weight of 40 kg and a power requirement of 90 watts), which should make this device usable in virtually any Antarctic field situation, has been achieved by the application of advanced recording technologies. The portability of this digital seismic recorder, when combined with its large bandwidth and dynamic range, should result in the resolution of a whole new class of intra- and subglacial phenomena, of which the thin basal layer of Ice Stream B is the first example.

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TRANSIENT TESTING OF SEISMIC RECORDING APPARATUS

Geophysics ◽

10.1190/1.1441815 ◽

1940 ◽

Vol 5 (4) ◽

pp. 337-347 ◽

Cited By ~ 2

Author(s):

Harold Washburn ◽

Raymond Olesen

Keyword(s):

Shaking Table ◽

High Fidelity ◽

Mechanical Motion ◽

Recording Equipment ◽

Recording Apparatus ◽

Response Characteristics ◽

Seismic Recording ◽

Actual Field ◽

Test Table

A transient generator and shaking table suitable for testing response characteristics of seismometers and associated amplifier and recording equipment is described. From variable‐area sound‐on‐film records representing idealized transients or actual field seismograph recordings, the generator and shaking table provide a high‐fidelity conversion to mechanical motion of the test table. The special experimental truck used in obtaining test records is also described briefly.

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Unbiased estimation of particle number and sizes using the new stereological tools: the disector, the fractionator, the selector, and the nucleator — or just point-sampled intercepts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100104200 ◽

1988 ◽

Vol 46 ◽

pp. 428-429

Author(s):

H.J.G. Gundersen

Keyword(s):

Particle Number ◽

Small Distance ◽

Parallel Plane ◽

Unbiased Estimation ◽

Severe Problem ◽

New Era ◽

Size And Shape ◽

Distinct Property ◽

Sectioned Tissue

Previously, all stereological estimation of particle number and sizes were based on models and notoriously gave biased results, were very inefficient to use and difficult to justify. For all references to old methods and a direct comparison with unbiased methods see recent reviews.The publication in 1984 of the DISECTOR, the first unbiased stereological probe for sampling and counting 3—D objects irrespective of their size and shape, signalled the new era in stereology — and give rise to a number of remarkably simple and efficient techniques based on its distinct property: It is the only known way to obtain an unbiased sample of 3-D objects (cells, organelles, etc). The principle is simple: within a 2-D unbiased frame count or sample only cells which are not hit by a parallel plane at a known, small distance h.The area of the frame and h must be known, which might sometimes in itself be a problem, albeit usually a small one. A more severe problem may arise because these constants are known at the scale of the fixed, embedded and sectioned tissue which is often shrunken considerably.

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Drug Induced Changes in Cell Organelles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100299 ◽

1968 ◽

Vol 26 ◽

pp. 110-111

Author(s):

Sarah A. Luse

Keyword(s):

Clinical Medicine ◽

Cell Organelles ◽

Riboflavin Deficiency ◽

Drug Induced ◽

New Era ◽

Health And Disease ◽

In The Beginning ◽

Cellular Pathology ◽

Induced Changes ◽

The Impact

In the mid-nineteenth century Virchow revolutionized pathology by introduction of the concept of “cellular pathology”. Today, a century later, this term has increasing significance in health and disease. We now are in the beginning of a new era in pathology, one which might well be termed “organelle pathology” or “subcellular pathology”. The impact of lysosomal diseases on clinical medicine exemplifies this role of pathology of organelles in elucidation of disease today.Another aspect of cell organelles of prime importance is their pathologic alteration by drugs, toxins, hormones and malnutrition. The sensitivity of cell organelles to minute alterations in their environment offers an accurate evaluation of the site of action of drugs in the study of both function and toxicity. Examples of mitochondrial lesions include the effect of DDD on the adrenal cortex, riboflavin deficiency on liver cells, elevated blood ammonia on the neuron and some 8-aminoquinolines on myocardium.

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