Showing papers on "Disturbance (geology) published in 1976"

Responses of wintering Brent Geese to human disturbance

Abstract: An assessment is given of the effects of human disturbance on the distribution and behaviour of Dark-bellied Brent Geese Branta bernicla bernicla wintering in Essex. Disturbed areas and places with poor visibility were avoided in early winter, but were used later when other areas became depleted of food. Geese became partially habituated to the proximity of people and to some loud noises, but not to small low-flying aircraft. The areas which contained the most geese apart from Foulness, namely Leigh Marsh and the Blackwater estuary, were also the most disturbed. Here, disturbance at weekends prevented geese from feeding for up to 11.7% of their time, and caused the time spent in flight to increase as much as sevenfold. Overall levels of disturbance were much lower than this, and would probably have been unimportant so long as adequate food was available on which geese could feed in undisturbed times, and at night. However, a shortage of food probably prevented complete compensation for the effects of disturbance. Disturbances could be greatly reduced by restricting access to the sea wall in certain areas around high tide, and by controlling the numbers of low-flying aircraft.

Stability and change in types of behavioral disturbance of children and adolescents.

Abstract: Changes with aging and stability of dimensions of behavioral disturbance were determined for 732 children and adolescents who constituted the sample reassessed after 5 years of an original cross-sectional sample of Manhattan youth 6 to 18 years old. On three of the six types of disturbance strongly related to the total impairment judgments of psychiatrists, specifically those tapping domains of aggression, greater or constant levels of pathology were noted over time. Cross-sectional versus longitudinal analyses on the same types of disturbance had discrepant results half the time. Stability coefficients for five of the six types of disturbance were greater than .55. Stability curves by age cohorts investigated whether a type of disturbance appeared transitory at certain age periods but more crystallized at other ages. Its prognostic significance would vary accordingly. Implications for intervention-treatment and for studies comparing the predictive value of different classes of behavior, e.g., neurotic versus antisocial, are discussed.

Some Climatological Aspects of West African Disturbance Lines During GATE

Abstract: The disturbance lines which occurred during the three phases of GATE over the eastern Atlantic Ocean and West Africa have been identified utilizing the excellent data from the SMS-1 geostationary satellite. The majority of these disturbance lines generated and decayed over land. Genesis occurred predominantly in the afternoon over land and in the early morning over water. They develop to the north of the cloud systems associated with the southwest monsoon, where the moist layer is shallow and the overriding dry air favors the production of downdrafts by the evaporation of precipitation and genesis is to a large extent dependent on insolation and low-level convergence associated with traveling waves.

Seismically-induced load structures in the basal Coal Measures, South Wales

Abstract: Within the basal Coal Measures between Ystradgynlais and Abercraf a number of liquefaction layers are seen displaying ball and pillow structures. These layers consist of balled-up, ovoid masses of sandstone some 0.25–0.3 m thick and 0.5–0.7 m across. It is considered that they were formed by loading, resulting from the lique-faction of underlying silts, produced by the passage of earthquake shock waves associated with the main fault zone of the Swansea Valley Disturbance. Elsewhere in South Wales, horizons displaying load and slump structures in rocks of Upper Palaeozoic age may have resulted from seismic shock waves caused by contemporary movements along major Variscan fractures.

Popular Protest and Disturbance in Kent, 1558–1640

Abstract: P OPULAR protest and disturbance was a recurrent phenomenon throughout much of Europe during the late sixteenth and early seventeenth centuries. Major risings erupted in Spain, the Netherlands, Austria, Italy and especially France. In England the only large-scale disturbance between the collapse of Wyatt's Revolt (I 554) and the outbreak of the Civil War was the mainly seigneurial Northern Rebellion of I 569.2 Nonetheless, there were many smallerscale disorders both in town and countryside. A few of these disturbances have already been discussed,3 but in general we know relatively little about the overall character of English popular protest at this time. How far did itjustify the picture of the many-headed monster, the violent, pauper, levelling mob denounced by Court propagandists and upper-class commentators ?4 How far was popular dis-

Structure and behavior of a monsoon cyclone over West Africa

Abstract: In this paper we present the results of a detailed synoptic compositing technique to determine the structure of a West African monsoon cyclone. The cyclone was in an early stage of development and was confined to the lower troposphere. Coastal weather along West Africa indicated the passage of this disturbance. This was noted from surface observations from ships of opportunity. A calculation of the meridional gradient of potential vorticity was carried out in the region of this disturbance. This calculation showed that the necessary condition for the existence of the combined barotropic-baroclinic instability was satisfied by these data. In order to go one step beyond the necessary conditions of this instability mechanism two very short range numerical prediction experiments are illustrated whose energetics confirm these results. Finally, we also present dynamic vertical motion distributions for this disturbance.

Habitat usage of wintering ducks at the Ouse Washes, England

Abstract: This paper describes some of the broad features governing habitat usage of wintering ducks at the Ouse Washes, England. They include flooding, disturbance, refuges, climate and availability of food.

Anti-theft alarm system

Abstract: An anti-theft alarm system is provided for detecting a desired disturbance to an associated structure wherein a momentary disturbance of the structure causes the alarm to emit a short audible warning blast and if the disturbance continues, thereafterwards, the alarm will remain on until the alarm system is deactivated.

Use of disturbance estimator for disturbance suppression

Abstract: This correspondence examines the use of a disturbance estimator for disturbance counteraction. This is done numerically on a longitudinal aircraft-control example. The disturbance-suppression controller is found to be effective under fairly adverse conditions and in the presence of wide deviations from the nominal disturbance.

Tragregelsysteme mit Störgrößenkompensation für Magnetschwebefahrzeuge / Disturbance rejection control systems for magnetically levitated vehicles

Abstract: Bei der Diskussion spurgebundener Hochleistungsverkehrssysteme stellt sich das elektromagnetisch getragene und geführte Fahrzeug mit Linearmotor-Antrieb als eine der interessantesten Entwicklungsprojekte dar. In dieser Arbeit wird auf den Entwurf von Tragregelsystemen fur Magnetschwebefahrzeuge eingegangen, wobei als wesentlichster Gesichtspunkt eine Störgrößenkompensation zur Tilgung der Fahrbahnstörungen betrachtet wird. Nach der Problembeschreibung werden zunächst die für die Regelkreissynthese benötigten Grundlagen zusammengestellt, wobei die Störgrößenaufschaltung für Mehrgrößenregelsysteme erläutert wird. Danach werden die einzelnen Rückführverstärkungen berechnet und das erhaltene Tragregelsystem mit Hilfe von Amplitudenfrequenzgängen beurteilt. Die Ergebnisse zeigen deutlich den Vorteil der Störgrößenkompensation. Nur bei einer Tilgung der Fahrbahnstörungen können Magnetschwebefahrzeuge ein für Fahrsicherheit und Fahrkomfort gutes Regelverhalten aufweisen.

Inland Wintering and Urban Roosting by Redshanks

Abstract: A study of Redshanks over the three winters 1972-75 on the River Kent at Kendal (Cumbria) show some interesting changes in behaviour. A flock of Redshanks now winters successfully and roosts on the roof-tops of an old building, illustrating an adaptation to disturbance in a newly acquired urban environment.

The role of biological disturbance in determining the organisation of sub-tidal encrusting communities in temperate waters

Abstract: Biological disturbance was found to be one of the most important mechanisms control1ing community organisation in the temperate sub-tidal region. The different types of biological disturbance structuring three encrusting communities were investigated on the east coast of Northland, New Zealand. The operation of each type was determined and the rate of disturbance measured. Experimental exclusion treatments were set up to demonstrate the effects of the major disturbance agents on community structure. The urchin Evechinus chloroticus was the most abundant agent of biological disturbance and affected the widest spectrum of encrusting organisms. The abundant balistid fish Navodon scaber was another major agent of biological disturbance in this region. Disturbance of algal populations also resulted from a guild of abundant herbivorous gastropods. Two episodes of fungal/bacterial infection degraded numbers of the large sponges Ancorina alata and Polymastia fusca. The operation of the different disturbance agents was found to be generally unpredictable in both time and space. There was no escape from biological disturbance for encrusting organisms in either small or large size. Re-occupation processes on patches of free primary space were investigated both experimentally and by using settlement plates (artificial free space patches). Recruitment was found to be irregular in space and time, especially for long-lived sessile organisms. Settlement processes as well as growth and mortality of newly settled organisms were investigated with a view to understanding community development. Only one verifiable example of substrate preparation or biological succession was found to operate in the communities studied. It is postulated that community organisation is flexible and not rigidly directed along a single successional pathway. Multiple developmental pathways and multiple stable configurations are possible in the same locality, resulting from the operation of different disturbance regimes.

Disturbance signal suppression circuit

Abstract: PURPOSE:To avoid the sound quality deterioration by varying the sensitivity of the disturbance signal detection circuit in accordance with S/N ratio.

On necessary and sufficient conditions of disturbance localization in single input-single output systems

Abstract: An existence condition, a stability condition, and a design method of a system in which the disturbance is localized are presented by using the zeros of the transfer function and the pole shifting method.

Signal receiving apparatus

Abstract: PURPOSE:To prevent induction disturbance from the vehicle in a signal receiving apparatus on teh ground for receiving signals from chopper controlled vehicles.