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951.
For systematic human Mars exploration, meeting crew safety requirements, it seems perspective to assemble into a spacecraft: an electrical rocket, a well-shielded long-term life support system, and a manipulator-robots operating in combined "presence effect" and "master-slave" mode. The electrical spacecraft would carry humans to the orbit of Mars, providing short distance (and low signal time delay) between operator and robot-manipulators, which are landed on the surface of the planet. Long-term hybrid biological and physical/chemical LSS could provide environment supporting human health and well being. Robot-manipulators operating in "presence effect" and "master-slave" mode exclude necessity of human landing on Martian surface decreasing the level of risk for crew. Since crewmen would not have direct contact with the Martian environment then the problem of mutual biological protection is essentially reduced. Lightweight robot-manipulators, without heavy life support systems and without the necessity of returning to the mother vessel, could be sent as scouts to different places on the planet surface, scanning the most interesting for exobiological research site. Some approximate estimations of electric spacecraft, long-term hybrid LSS, radiation protection and mission parameters are conducted and discussed.  相似文献   
952.
The results of cross-correlation analysis between electrons fluxes (with energies of > 0.6MeV, > 2.0 MeV and > 4.0MeV), geomagnetic indices and solar wind parameters are shown in the paper. It is determined that the electron fluxes are controlled not only by the geomagnetic indices, but also by the solar wind parameters, and the solar wind velocity demonstrates the best relation with the electron fluxes. Numerical value of the relation efficiency of external parameters with the highly energetic electrons fluxes shows a periodicity. It is presented here the preliminary results of daily averaged electrons fluxes forecast for a day ahead on the basis of the model of neuron networks.  相似文献   
953.
Empirical magnetic field models are compared with high-altitude magnetic field measurements and results from an MHD simulation. Comparison of the T96 model and observations from GOES-8 and GOES-9 shows that if the observed solar wind and IMF parameters are used to compute the model field, the model field is more stretched than the observed field. On the other hand, if measurements made by one spacecraft are used to find the model parameters that give a best-fit field at that location, the RMS error can be reduced also at the other spacecraft four hours away in local time. Comparison of T96 model and MHD simulation results shows that the empirical models have a thinner current sheet than the MHD simulation, but that the lobe field values are quite similar to each other. Furthermore, a comparison of an event-oriented, modified T89 model and MHD simulation by Pulkkinen et al. [2000] reveals that if the empirical model is constructed by fitting to in-situ measurements, the resulting model is very similar to the MHD simulation magnetic field. These results indicate that an efficient method of utilizing the present-day empirical models is to select model parameters based on measurements from a few individual points.  相似文献   
954.
For extended duration missions in space the supply of basic life-supporting ingredients represents a formidable logistics problem. Storage volume and launch weight of water, oxygen and food in a conventional non-regenerable life support system are directly proportional to the crew size and the length of the mission. In view of spacecraft payload limitations this will require that the carbon, or food, recycling loop, the third and final part in the life support system, be closed to further reduce logistics cost. This will be practical only if advanced life support systems can be developed in which metabolic waste products are regenerated and food is produced.

Biological Life Support Systems (BLSS) satisfy the space station environmental control functions and close the food cycle. A Biological Life Support System has to be a balanced ecological system, biotechnical in nature and consisting of some combination of human beings, animals, plants and microorganisms integrated with mechanical and physico-chemical hardware.

Numerous scientific space experiments have been delineated in recent years, the results of which are applicable to the support of BLSS concepts. Furthermore ecological life support systems have become subject to intensified studies and experiments both in the U.S. and the U.S.S.R. The Japanese have also conducted detailed preliminary studies.

Dornier System has in recent years undertaken an effort to define requirements and concepts and to analyse the feasibility of BLSS for space applications. Analyses of the BLSS energy-mass relation have been performed, and the possibilities to influence it to achieve advantages for the BLSS (compared with physico-chemical systems) have been determined. The major problem areas which need immediate attention have been defined, and a programme for the development of BLSS has been proposed.  相似文献   

955.
Infrared spectra of Venus measured by means of the Fourier spectrometer aboard Venera 15 orbiter were used for retrievals of temperature profiles of the atmosphere in the altitude range from 60 to 95 km. Monotonous profiles are typical for latitudes lower than 60° latitude, but on the dayside near the equator some traces of the upper atmospheric inversion were found in the profiles. At latitudes greater than 60°N the profiles contain an isothermal or inversional part between 10 and 100 hPa pressure levels. Temperature profiles inside the “warm dipole” maxima are the same as outside of this region and consequently these optical properties should be explained only by peculiarities of cloud structure there.  相似文献   
956.
This paper presents the controller synthesis for an unmanned helicopter with minimum initial information about the parameters of its mathematical model with time-delays of measured and control signals. The unknown parameters, wind disturbances, and system nonlinearity are considered as external disturbances that are estimated using a multi-gap observer. The estimates obtained are used in the control law to improve the stability rate for flight regimes.  相似文献   
957.
The results of experiments that were performed to test the feasibility of creating sandwich structures (consisting of thin-layer sheaths of polymer composites and a cellular polymer core) with the shapememory effect as models of the transformable components of space structures have been given. The data obtained indicate that samples of sandwich structures under microgravity conditions on board the International Space Station have recovered their shape to almost the same degree as under terrestrial conditions, which makes it possible to recommend them for creating components of transformable space structures on their basis.  相似文献   
958.
959.
A study is made to define a procedure of cooperative processing of goniometric and range difference measurements in multilateral system of passive radiolocation. As a result, we worked out the computational algorithms, which implement this procedure. The accuracy characteristics are estimated.  相似文献   
960.
This paper considers the problem of increasing the fuel efficiency of a diesel aircraft engine and decreasing the smokiness of its exhaust gases (EG) by means of the experimental determination of optimum compression ratio and combustion chamber dimensions. Necessity for matching of these parameters in a wide variation range of load and crankshaft speed was identified and proved.  相似文献   
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