Blackout as an expression of fluctuations in blood pressure in steep dives
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Simplified equations are presented for estimating the length and weight of major powerplant components of VTOL aircraft. The equations were developed from correlations of lift and cruise engine data. Components involved include fan, fan duct, compressor, combustor, turbine, structure, and accessories. Comparisons of actual and calculated total engine weights are included for several representative engines.
The problem is considered of classifying into one of m distinct n-variate classes an arbitrary n-channel multispectral measurement vector x. The classification procedure used is the maximum likelihood procedure. Information loss in compressing the n-channel data to k channels is taken to be the difference in the average interclass divergences (or probability of misclassification) in n-space and in k-space. Data compression is accomplished by kxn linear transformation i.e., multiplication of the spectral n-vector by a kxn matrix of rank k.
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A Seasat image (23.5 cm wavelength) of the Durmid Hills in southern California, the San Andreas Fault was analyzed. It is shown that a prominent southeast trending tonal lineament exists that is bright on the southwest side and dark on the northeast side. The cause of the contrasting signatures on opposite sides of the lineament was determined and the geologic signficance of the lineament was evaluated.
Mapping of minor lineaments from radar imagery of the rain forest in southeast Peru is biased due to the selective suppression of some topography which results from the observation geometry of the imaging radar system and the varied perception of lineaments on the imagery by different interpreters. Team analysis of the imagery compensates for several of the sources of bias, and results in the clear recognition of differing regimes within the regional fracture field in the study area.
Starting with the basic fatigue lift formula, an inversion formula is derived. The inversion formula is valid over the entire life range of engineering interest for all materials examined. Conformity between the two equations is extremely close, suitable for all engineering problems. The approach used to invert the life relation is also suitable for the inversion of other formulas involving the sum of two power-law terms.
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An equivalent layer magnetization model is discussed. Inversion of long wavelength satellite magnetic anomaly data indicates a very magnetic source region centered in south central Kentucky. Refraction profiles suggest that the source of the gravity anomaly is a large mass of rock occupying much of the crustal thickness. The outline of the source delineated by gravity contours is also discernible in aeromagnetic anomaly patterns. The mafic plutonic complex, and several lines of evidence are consistent with a rift association. The body is, however, clearly related to the inferred position of the Grenville Front. It is bounded on the north by the fault zones of the 38th Parallel Lineament. It is suggested that such magnetization levels are achieved with magnetic mineralogies produced by normal oxidation and metamorphic processes and enhanced by viscous build-up, especially in mafic rocks of alkaline character.
The acoustical index leg was studied to determine its accuracy in predicting annoyance from traffic noise. Annoyance was tested in experimental situations where the frequency of the number of heavy vehicles varied from 3 to 30 HV/30 min for different classes of the Leg level at 50, 55, 60 dB(A) of traffic noise. The results showed that: (1) for a constant Leg level the annoyance increases as a function of the number of HV up to a certain threshold at which the annoyance is stabilized; (2) for a constant frequency of passage of HV, the annoyance increases with the Leg level; (3) composite indexes of the type Leg + Log NHV, L1 + EMER or L1 + L10 give a predictive value greater than that of the Leg pr Log nHV taken alone.
(Previously announced in STAR as N82-17715)
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It is pointed out that some important agricultural crops show heliotropic leaf movements. In these species, the proclivity of leaves to orient either perpendicularly or parallel or in some combination of these positions with respect to the sun is controlled by the leaf turgor and the availability of water. Such an orientational response is particularly noticeable for cotton. Schutt et al. (1985) have detailed leaf trajectories using three angles. The present investigation applies the three-angle representation to leaf trajectory mapping and to the calculation of the phase angle 'gamma' between the individual leaf normals and the solar direction. Using gamma, the thermodynamic work and entropy functions are evaluated and used to distinguish between the behavior of water-stressed and well watered cotton canopies.
Metamorphic core complexes and detachment fault terranes in the American Southwest are products of stretching of continental crust in the Tertiary. The physical and geometric properties of the structures, fault rocks, and contact relationships that developed as a consequence of the extension are especially well displayed in southeastern Arizona. The structures and fault rocks, as a system, reflect a ductile-through-brittle continuum of deformation, with individual structures and faults rocks showing remarkably coordinated strain and displacement patterns. Careful mapping and analysis of the structural system has led to the realization that strain and displacement were partitioned across a host of structures, through a spectrum of scales, in rocks of progressively changing rheology. By integrating observations made in different parts of the extensional system, especially at different inferred depth levels, it has been possible to construct a descriptive/kinematic model of the progressive deformation that achieved continental crustal extension in general, and the development of metamorphic core complexes in particular.
The creation of high-power pulsed CO2 and Nd-glass lasers enables the realization of the method for remote spectro-chemical analysis of atmospheric aerosols based on excitation of the emission spectrum of the aerosol particle atoms. A description of construction and characteristics of a spectrochemical lidar based on both Nd-glass and CO2 lasers is presented.
The radial integral for 1s2 1S-1s np 1P transitions of the He isoelectronic sequence is asymptotically expanded to order n exp -7 to facilitate calculations of the dipole oscillator strength for large n. The threshold differential oscillator strength values are obtained for ions up to Z = 30 within the screened hydrogenic model.