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91.
92.
To examine the developmental significance of mirrow self-recognition in early childhood, a cross-sectional study with 55 Down's syndrome children was conducted. When their image is altered by rouge on the nose, normal infants by 22 months indicate self-recognition by touching their noses while looking in the mirror. Only a small percentage of Down's syndrome children touched their noses by this age, confirming the expected lag in this development. However, those young Down's syndrome infants with near-normal development quotient did manifest the reaction. In general, when developmental age was equated, the Down's syndrome children showed parallel development to normal children. 相似文献
93.
The reproducibility of microwave integrated circuits can be improved by employing substrates which are anisotropic. A method is presented which facilitates the computation of the characteristics of distributed integrated microwave circuits of finite conductor thickness on anisotropic and inhomogeneous substrates. The method is variational and it relies on a quasi-static approach which assumes that the charge distribution on each side of the conductor can be represented by a spatially dependent set of exponential functions. 相似文献
94.
It is often desirable to represent carrier distribution systems by networks so that analysis can be made to predict the behavior of these systems. Modeling of two canonical carrier distribution systems, the star-shaped system and the parallel-wire system by networks was carried out in this paper. The representation is given in terms of lumped parameters when the lengths of the carrier lines are short and it is given in terms of lumped and distributed parameters when the lengths of the carrier lines are long. 相似文献
95.
Victor D Hopper 《Endeavour》1978,2(3):121-126
Measurement of vertical and horizontal wind velocity is of great importance in many contexts, such as investigation of air pollution, weather forecasting, and air-traffic control. In recent years continuously recording acoustic sounders have been developed which give reliable results at reasonable cost: some 200 are now in use in at least 15 countries. 相似文献
96.
D P Biklen 《American annals of the deaf》1975,120(4):382-386
97.
G.K. Wertheim 《Journal of The Franklin Institute》1974,298(4):289-298
The principles of X-ray photoelectron spectroscopy are outlined. The application of this technique to the study of the electronic structure of metals, alloys and compounds is illustrated using data in Ag, β-brass, ReO3 and VO2. In the latter a major change in the density of states is observed on passing through the metal-insulator transition. 相似文献
98.
99.
Georges D. Szakasits 《Research Policy》1974,3(1):18-28
The article deals with the results achieved by the adoption of the SAPPHO method (developed by the Science Policy Research Unit of Sussex University) to the conditions of the Hungarian electronics industry. The results coincide to a great extent with those established in the course of the survey made in England, although there are some significant differences. 相似文献
100.