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81.
82.
This review assumes that many non-US readers may not be well-informed about the steps and work in radar development in the US after WW II to the present. Many know MIT by name and recall the famous Radiation Laboratory Series. But the more recent technical history has been less in the "public domain." In an attempt to correct this, one of the key institutions in the field, the MIT Lincoln Laboratory two years ago produced a special issue of their regular publication. Although the document currently at hand is not a book in the strict sense, the size, shape, and editorial comprehensiveness of the MIT Lincoln Laboratory Journal's Fifty-Year Anniversary Issue (12, 2, 2000) justifies calling this article being treated as a book review. 相似文献
83.
The fine structure of the Auroral Kilometric Radiation (AKR) is studied using multicomponent measurements of the electric component of the electromagnetic field in the frequency band 4 kHz–1 MHz (the POLRAD experiment onboard the INTERBALL-2 satellite). Special attention is paid to the measurements near the source of the AKR: under conditions when the lower boundary of the emission range descended sufficiently low, down to the local gyrofrequency of electrons. From the analysis of the electric field structure the conclusion is drawn that the bulk of the AKR power is carried by the signal component fast variable in time and frequency (flickering component). The power of a constant component (continuum) is lower by at least an order of magnitude. During strong bursts of the AKR, the relative contribution of the flickering component increases. The spatial structure of the zone of generation has at least three characteristic scales along and across the magnetic field. 相似文献
84.
A Izumi-Kurotani M Yamashita Y Kawasaki 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1992,12(1):263-266
Japanese treefrogs (Hyla japonica) are planned to be sent to the space station MIR. Experimental system was developed to observe their behaviors under microgravity. 相似文献
85.
Liu S. Singer C.H. Dougal R.A. 《IEEE transactions on aerospace and electronic systems》2006,42(2):612-624
Electric power anomalies or disturbances can disrupt the normal operation of equipment, accelerate aging, or even cause outright failures thus resulting in increased costs of maintenance and reduced system reliability. Past research on the effects caused by power anomalies has been mostly focused on industrial, commercial, or residential systems, or on power distribution equipment. A literature survey reveals that there is no comprehensive review related to low-voltage (LV) power systems and utilization equipment applicable to military combat vehicles, such as aircraft and ships. This paper summarizes the results of a new literature survey that focused on the causes, effects, and mitigation methods for power anomalies typical of LV mobile power systems. Electric power anomaly cost data collected from the literature are also presented, from which the costs of anomalies to the national defense are estimated using some simple rationales. 相似文献
86.
Teofilo V.L. Merritt L.V. Hollandsworth R.P. 《Aerospace and Electronic Systems Magazine, IEEE》1997,12(11):30-36
A lithium ion battery charger has been developed for four and eight cell batteries or multiples thereof. This charger has the advantage over those using commercial lithium ion charging chips in that the individual cells are allowed to be taper charged at their upper charging voltage rather than be cutoff when all cells of the string have reached the upper charging voltage limit. Since 30-60% of the capacity of lithium ion cells may be restored during the taper charge, this charger has a distinct benefit of fully charging lithium ion batteries by restoring all of the available capacity to all of its cells 相似文献
87.
88.
A multiple model adaptive estimator (MMAE) has been formulated to estimate the state of a dynamic system modeled by a linear stochastic differential equation, from which measurements, described as a noise-corrupted space-time point process functionally related to that state, are extracted. Assumed certainty equivalence is used to combine such an estimator with the LQ full-state feedback controller to synthesize a practical, implementable controller. Performance of the estimator and resultant controller characteristics are investigated via simulation as a function of approximation method used to limit the full-scale estimator to finite dimensionality and also as a function of important parameters defining the dynamics and observation processes. 相似文献
89.
Tikhomirov AA Ushakova SA Manukovsky NS Lisovsky GM Kudenko YA Kovalev VS Gribovskaya IV Tirrannen LS Zolotukhin IG Gros JB Lasseur Ch 《Acta Astronautica》2003,53(4-10):249-257
The paper considers problems of biosynthesis of higher plants' biomass and "biological incineration" of plant wastes in a working physical model of biological LSS. The plant wastes are "biologically incinerated" in a special heterotrophic block involving Californian worms, mushrooms and straw. The block processes plant wastes (straw, haulms) to produce soil-like substrate (SLS) on which plants (wheat, radish) are grown. Gas exchange in such a system consists of respiratory gas exchange of SLS and photosynthesis and respiration of plants. Specifics of gas exchange dynamics of high plants--SLS complex has been considered. Relationship between such a gas exchange and PAR irradiance and age of plants has been established. Nitrogen and iron were found to the first to limit plants' growth on SLS when process conditions are deranged. The SLS microflora has been found to have different kinds of ammonifying and denitrifying bacteria which is indicative of intensive transformation of nitrogen-containing compounds. The number of physiological groups of microorganisms in SLS was, on the whole, steady. As a result, organic substances--products of exchange of plants and microorganisms were not accumulated in the medium, but mineralized and assimilated by the biocenosis. Experiments showed that the developed model of a man-made ecosystem realized complete utilization of plant wastes and involved them into the intrasystem turnover. 相似文献
90.
V. M. Gotlib E. N. Evlanov B. V. Zubkov V. M. Linkin A. B. Manukin S. N. Podkolzin V. I. Rebrov 《Cosmic Research》2004,42(1):54-59
A quartz sensor of small accelerations with a capacitive transducer is designed and produced, allowing one to measure spacecraft accelerations with a resolution of 10–7 m/s2 in the range ±10–1 m/s2. The results of calibration of the sensor by the method of inclinations are presented. 相似文献