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141.
An experiment to determine the forward-scattering complex amplitude functions of waterdrops supported in a vertical wind tunnel is described. The measuring system is calibrated using a metal sphere of accurately known diameter. Measurements at 11 GHz on waterdrops in the range 1.6?3.1 mm radius are compared with theoretical values obtained by Oguchi using the point-matching technique. 相似文献
142.
The map displays project was undertaken to investigate techniques for the storage and display of geographical maps and related information and to develop the hardware and software required for a complete working system. Initially most of the project was concerned with the design of graphics hardware to be interfaced to a DEC LSI-11/03 micro-computer which was the main supply of computing power for the project. The development of one of the pieces of specialized hardware, the framestore display, is described. 相似文献
143.
Watson Charles G.; Thomas Richard W.; Anderson Dennis; Felling James 《Canadian Metallurgical Quarterly》1968,32(6):679
Attempted to determine whether the Reitan-Halstead Organic Test Battery separates neuropsychiatric hospital organics from schizophrenics. It was administered to 25 schizophrenics and 25 cerebral-lesion organics at each of 2 chronicity levels. Only 1 of the 24 diagnosis/diagnosis * chronicity effects used to evaluate the data was significant at the .05 level, indicating that actuarial application of Reitan-Halstead scores is of no practical value in the separation of the 2 groups. To determine whether expert clinicians might improve upon the actuarial results, protocols of 24 schizophrenics and 24 organics were sent to 8 Reitan-Halstead experts who were instructed to separate them into brain-damaged and schizophrenic diagnostic groups. The mean number of correct classifications, 25.5 out of 48 suggested that clinical judgment added nothing to actuarial prediction in this case. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
144.
CG Watson 《Canadian Metallurgical Quarterly》1976,31(5):611-616
Eighty-four geriatirc ward patients were randomly assigned to groups targeted for outplacement planning or inpatient care. During the following year, half of the former were placed in community settings while nearly all of the latter remained in the hospital. Neither the physical health, level of self-care, or psychiatric condition ratings of the two groups changed differentially over that time. However, the mean Morale Inventory score of the outplacement sample improved while that of the in-patient group remained static. Additional analyses were run between three groups - outplacement planning subjects who were released, those who were not released, and inpatient planning men who were not released. These results confirmed those of the first analyses; the only significant difference appeared on the Morale Inventory, the patients who left showing more improvement than the other two groups. The results argue for an increased emphasis on outplacement programs among geriatric patients. 相似文献
145.
Pentobarbital pellet implantation increased more than 200% the ED50 dose of pentobarbital required to induce loss of the righting reflex within 2 min of i.p. injection and increased the onset of barbital-induced sleep. Both tests of functional barbiturate tolerance were blocked by the intraventricular injection of cycloheximide. The effects of acute (45 mg/kg i.p.) and chronic (pellet implantation) pentobarbital treatment on the incorporation of 3/-lysine into the protein of various subcellular fractions of the cortex and subcortex were studied. In the subcortex, chronic pentobarbital treatment significantly stimulated protein synthesis 40-50% in the microsomal, soluble and mitochondrial fractions. Both acute and chronic pentobarbital treatments significantly increased (3H-lys)-protein accumulation in a fraction of synaptic plasma membranes derived from a population of nerve ending particles (NEP) enriched in gamma-aminobutyric acid (GABA). The possible significance of these data to pentobarbital tolerance and dependence development is discussed. 相似文献
146.
Measurements of linear cross polarization and attenuation on a terrestrial link in the U.K. are reported and correlated with rainfall information. The cross polarization measured during rainfall is compared with theoretically predicted values and monthly cross-polar statistics are presented for a 16-month period. 相似文献
147.
Attenuation and phase coefficients are evaluated for microwave radio propagation through oblate spheroidal raindrops on slant radio paths. From these coefficients, it is evident that the resultant crosspolarisation for linearly or circularly polarised waves should be significantly less on satellite radio paths than on horizontal radio paths. 相似文献
148.
J. C. Lachat J. O. Watson 《International journal for numerical methods in engineering》1976,10(5):991-1005
The field equations of three-dimensional elastostatics are transformed to boundary integral equations. The elastic body is divided into subregions, and the surface and interfaces are represented by quadrilateral and triangular elements with quadratic variation of geometry and linear, quadratic or cubic variation of displacement and traction with respect to intrinsic co-ordinates. The integral equation is discretized for each subregion, and a system of banded form obtained. For the integration of kernel-shape function products, Gaussian quadrature formulae are chosen according to upper bounds for error in terms of derivatives of the integrands. Use of the integral formulation is illustrated by the analysis of a prestressed concrete nuclear reactor pressure vessel. 相似文献
149.
150.
A theory on the shielding effectiveness of n coaxial metallic tubings which shield a coaxial cable has been developed based on electromagnetic (EM) field theory. The theory holds for all homogeneous, linear, and isotropic shields, magnetic or nonmagnetic, and covers essentially the entire frequency range. When a cable carries an evenly distributed axial current, the dominant mode of propagation is transverse magnetic (TM) and has only three field components, i.e., Ez, H?, and Er. The fields of the dominant mode leaking from the cable, with and without shields, have been determined rigorously from the solutions of Maxwell's equations and boundary conditions. The shielding effectiveness of the tubings, defined as the insertion loss, has thus been readily obtained. To simplify the obtained expressions to a certain degree such that numerical calculations are manageable, various approximations have been introduced and precisely justified. The limitations imposed on the simplified expression due to the approximations have been clearly listed. It has been shown that Schelkunoff's shielding theory is merely a special case of the present work. As an example, the shielding effectiveness of a single copper tubing surrounding an RG-8/U cable has been considered. The data measured from a carefully designed experimental setup show that at high frequencies, i.e., above 10 kHz, the curve predicted by the present work is about 1 dB above the empirical curve, while the curve due to Schelkunoff is about 5 dB below the empirical curve. At low frequencies, i.e. 相似文献