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761.
Bozzi S. Capigatti U. Cappellini V. Re E.D. Margheri M. Saltini I. 《IEEE transactions on aerospace and electronic systems》1982,(5):704-708
The design and implementation of a second-order nonrecursive moving target indication (MTI) radar filter using commercially available charge-transfer devices as delay lines are described. A simple technique is included to compensate for the device charge-transfer in-efficiency and its sensitivity is analyzed. Experimental laboratory tests and results in an operating radar system are reported showing the good performance of the realized MTI radar filter. 相似文献
762.
This paper identifies the design features of commercial-off-the-shelf (COTS) software that impact the lifecycle cost of automatic test system (ATS) solutions and provides a set of design guidelines. It demonstrates that the architecture of COTS software must be modular, based on correct functional allocation, should possess distribution capabilities, and contain open interfaces that remain backwards compatible. In the case of COTS development tools, the programmatic interface should be simple, extensible, and enforced in the development environment. 相似文献
763.
L T Mishchenko A M Silayeva I A Mishchenko A L Boyko 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(7):1607-1611
The effects of clinostating on physiological processes and biochemical characteristics of wheat plants (Triticum aestivum L.) both healthy and infected by the wheat streak mosaic virus (WSMV) were studied. In six experiments, each lasting over 30 days, healthy and infected plants of the dwarf Apogee variety were grown under conditions of continuous horizontal and vertical clinostating with 2 rpm at 21 +/- 2 degrees C and 6000 1x (the optimal moisture of a substrate being maintained). The control variants (healthy and infected) were simultaneously grown under the same conditions of temperature and illumination in stationary containers and in open pots. During the experiment, visual observations were carried out over the state of tested plants. After completing the experiment, biometric indices, pigment, carbohydrate and dry matter contents were determined in all the plants. It was shown that clinostating sharply reduced the reproductive function of healthy plants and considerably affected their biomass (productivity) and concentration of chlorophylls and sugars. The viral infection resulted in further reduction of these characteristics. In control variants the viral effect was more significant. We speculate that clinostating reduced the rate of reproduction and spread of the virus. 相似文献
764.
V.K. Golev I.M. Yancoulova G.T. Petrov 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
Based on the spectrophotometric data, by decomposition of the observed continuum, the power - law continuum characteristics of the central source are obtained. The behaviour of both electron temperature Te and density ne in the Narrow - Line Region (NLR) of NGC 7469 is discussed on the thermal and ionization equilibria calculations. Te in NLR of the Sy1 galaxies are higher than the Sy2 ones, and the possible explanation is the lack of the dense (ne 1010 cm−3) zone close to the central source in the Sy2 galaxies. 相似文献
765.
766.
I A Akhmadieva AKhAptikaeva GPh Livanova A V Antipov I G Akoev E E Ganassi 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(10):227-230
The cell culture of a Chinese hamster was irradiated on a Serpuchov proton synchrotron at a dose of 0.5-4 Gy and a dose rate of 1 Gy/min and by gamma-irradiation at dose 1-5 Gy and dose rate 1.2-1.4 Gy/min. The effect of radiation on the cell culture was judged from chromosomal aberrations in G2-stage of cell cycle and micronuclear test. The relative biological efficience of the secondary radiation was approximately 3. Modifying effect of caffeine on the cells irradiated by secondary radiation of synchrotron was not observed. In the presence of caffeine the effect of gamma-irradiation practically is increased up to the level observed upon secondary irradiation. This suggests that secondary radiation inhibits the repair of the cytogenetic damage. 相似文献
767.
The influence of the instrumented range on the selection of the radar parameters for maximal detection range is described. Procedures for optimization of the performance of the radar by an appropriate setting of its parameters, for specified instrumented range, are presented. 相似文献
768.
769.
The problem of the interpretation of measurements made by means of a convection sensor is considered. The sensor is a cubic chamber filled by a viscous fluid (gas). Fixed and unequal temperatures are maintained on two opposite sides of the cube; the other sides are perfect heat conductors. Two differential thermocouples are placed inside the chamber to measure the temperature difference at two pairs of fixed points. The sensor is mounted aboard the Earth's satellite. Mathematical models of various degrees of complexity are proposed which describe processes of heat and mass transfer under the action of a quasistatic component of microaccelerations. The results of mathematical simulation of the data of sensor thermocouples presenting a response to the real quasistatic component of microaccelerations which took place aboard the Mirstation are given. It is shown that under usual conditions of an orbital mission the sensor presents a linear low-frequency filter. By combining the data of several identical sensors, tightly arranged and oriented in a certain way, it is possible to measure low-frequency components of the angular acceleration of the satellite and linear microaccelerations at the point of the sensor position. 相似文献
770.
B. Kneissel G. H. Schwehm C. Leinert I. Richter B. Planck 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(12):163-166
Shortly after it passed through perihelion on February 25, 1976 Comet West was observed by the Helios Zodiacal Light Experiment. Broadband photopolarimetric measurements of the head and of the tail were performed in three wavelength bands (U, B, V). The phase angles encountered range from 67° to 85°. The polarization measurements indicated wavelength independent linear polarization. The maximum degree of polarization in the visual channel was found to be .28 at a phase angle of 83°. 相似文献