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281.
Hardware-in-the-loop testing technology for automatic control, condition monitoring and diagnostics systems of gas turbine engines is described. The technology proposed makes it possible to simulate combinations and chains of unexpected and gradual failures of engines, transducers and actuators. 相似文献
282.
I. Sh. Sharafeev 《Russian Aeronautics (Iz VUZ)》2009,52(2):255-258
A set of systems for labor standard computer-aided design is described, namely, initial developments, advance and state-of-the art. 相似文献
283.
Some experimental data on the process of impulsive ultrasonic machining are presented. Also given are the data on variations in the impulsive vibration frequency of a workpiece and a tool. 相似文献
284.
V. A. Ryabyi V. A. Obukhov A. P. Kirpichnikov P. E. Masherov A. I. Mogulkin 《Russian Aeronautics (Iz VUZ)》2015,58(4):448-453
A technique of integral diagnostics for an RF inductively coupled plasma gas discharge unit of an ion thruster is proposed. This technique includes a priori measurements of antenna coil electrical parameters in free space and in assembled state as well as experimental determination of the antenna coil currents with and without discharge. 相似文献
285.
Understanding properties of solar energetic particle (SEP) events associated with coronal mass ejections has been identified
as a key problem in solar-terrestrial physics. Although recent CME shock acceleration models are highly promising, detailed
agreement between theoretical predictions and observations has remained elusive. Recent observations from ACE have shown substantial
enrichments in the abundances of 3He and He+ ions which are extremely rare in the thermal solar wind plasma. Consequently, these ions act as tracers of their source material,
i.e.,
3He ions are flare suprathermals and He+ ions are interstellar pickup ions. The average heavy ion composition also exhibits unsystematic differences when compared
with the solar wind values, but correlates significantly with the ambient suprathermal material abundances. Taken together
these results provide compelling evidence that CME-driven shocks draw their source material from the ubiquitous but largely
unexplored suprathermal tail rather than from the more abundant solar wind peak. However, the suprathermal energy regime has
many more contributors and exhibits much larger variability than the solar wind, and as such needs to be investigated more
thoroughly. Answers to fundamental new questions regarding the preferred injection of the suprathermal ions, the spatial and
temporal dependence of the various sources, and the causes of their variability and their effects on the SEP properties are
needed to improve agreement between the simulations and observations. 相似文献
286.
287.
One possible method is considered of deriving the well-posed (in the sense of A.N. Tikhonov) solutions to the problems of estimating the aircraft performance characteristics. The method is based on the results of measurements of the state parameters and geophysical conditions of the employment of the rocket-and-space facilities under conditions of uncertainty of the a priori data on measurement errors. 相似文献
288.
Y Kitaya A Tani M Kiyota I Aiga 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(11):281-284
In order to obtain basic data for construction of a plant cultivation system incorporating a mushroom cultivation subsystem in the CELSS, plant growth and atmospheric CO2 balance in the system were investigated. The plant growth was promoted by a high level of CO2 which resulted from the respiration of the mushroom mycelium in the system. The atmospheric CO2 concentration inside the system changed significantly due to the slight change in the net photosynthetic rate of plants and/or the respiration rate of the mushroom when the plant cultivation system combined directly with the mushroom cultivation subsystem. 相似文献
289.
I Block A Wolke W Briegleb 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1994,14(8):21-34
The acellular slime mold Physarum polycephalum is used as a model system to investigate the graviresponse of single cells which possess no receptors specialized for the perception of gravity. To obtain insights into the gravity-signal transduction mechanism the light response of the cell is used: Macroplasmodia of the slime mold show clear geo- and phototaxes. Gravity increases and white light decreases transiently the contraction frequency of plasmodial strands whereby both responses follow the same time pattern. Since mitochondria play a major role in changing the contraction rhythm in response to light and gravity stimuli, the simultaneous and subsequent inductions of the opposing light and gravity responses and their mutual influences on one another were investigated. The experiments were performed in weightlessness (0 g)--simulated on the fast-rotating clinostat as well as in actual weightlessness during the IML-1 Space Shuttle mission. The results indicate that mitochondria (chondriome) are part of the acceleration-stimulus reaction chain in Physarum. Two models for a direct gravireceptor mechanism are discussed. 相似文献
290.
A N Boyandin T I Lobova L Yu Popova N S Pechurkin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2003,31(7):1763-1768
It has been demonstrated that the transgenic microorganism Escherichia coli Z905/pPHL7 (AprLux+) can exist for a long time at an elevated concentration of mineral salts. The microorganism was introduced into microcosms with sterile brackish water (salinity variable from 21 to 22 g l-1) taken from Lake Shira (Khakasia, Russia). The survival of the microorganism was estimated both by measuring the growth of the colonies on solid nutrient media and by the bioluminescence exhibited by the transgenic strain in samples from the microcosms and in the enrichment culture with the added selective factor-ampicillin (50 micrograms/ml). In the enrichment culture, the bioluminescent signal was registered through the 160-day experiment. It has been shown that in the closed microcosms with brackish water the E. coli strain becomes heterogeneous in its ampicillin resistance. The populations of the transgenic strain were mainly represented by isolates able to persist in the medium containing 50 micrograms/ml, but there were also the cells (about 10%) with the threshold of ampicillin resistance not more than 0.05 micrograms/ml. Thus, it was shown that in the microcosms with brackish water and in the absence of the selective factor the transgenic strain survives and retails the recombinant plasmid. 相似文献