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971.
This paper reports on the Dancer project, which is one of three related projects initiated by working group 1 of the International Association of Geodesy. The Dancer project develops JAVA parameter estimation software that runs in the form of a distributed process on the internet, in such a way that each processing node handles the data of a single geodetic instrument. By exchanging a minimum amount of information among all processing nodes, the same global normal equation solution is found by all instruments. The result is a fully scalable least squares solution that has no practical limit to the number of GPS receivers or other tracking devices that may be included in a single reference frame realization.  相似文献   
972.
The design of the Lunar Exploration Neutron Detector (LEND) experiment is presented, which was optimized to address several of the primary measurement requirements of NASA’s Lunar Reconnaissance Orbiter (LRO): high spatial resolution hydrogen mapping of the Moon’s upper-most surface, identification of putative deposits of appreciable near-surface water ice in the Moon’s polar cold traps, and characterization of the human-relevant space radiation environment in lunar orbit. A comprehensive program of LEND instrument physical calibrations is discussed and the baseline scenario of LEND observations from the primary LRO lunar orbit is presented. LEND data products will be useful for determining the next stages of the emerging global lunar exploration program, and they will facilitate the study of the physics of hydrogen implantation and diffusion in the regolith, test the presence of water ice deposits in lunar cold polar traps, and investigate the role of neutrons within the radiation environment of the shallow lunar surface.  相似文献   
973.
Problems of improving the efficiency of design works in the process of space-rocket complex (SRC) updating are considered. The methodical foundation for the expert system application to form promising technical solutions in studying the flight vehicle (FV) modification is presented.  相似文献   
974.
Basic principles of a mathematical model for disk-wing aircraft balancing and evaluation of power expenditure for flight as compared with a helicopter are presented.  相似文献   
975.
Methodology of constructing a stationary multichannel flow aerometric receiver using the effects of deceleration and throttling of an incoming airflow and their circular transformation in the yaw plane is considered. The mathematical models and algorithms for processing primary informative signals entering along the channels of speed, altitude, angles of attack and slip of the helicopter air data system constructed on the basis of the aerometric receiver being proposed are obtained.  相似文献   
976.
A method for calculating the flowrate of the gas flowing through the cellular insert cells over the labyrinth seal strip is proposed. The gas density is taken to be average with respect to the decisive section. It is assumed that jets flowing out of cells disrupt the direct flow of the labyrinth seal. A practical implementation of the method is confirmed by the known experimental data.  相似文献   
977.
A technique for numerical finite element analysis of large elastoplastic strains is proposed. A problem is formulated in terms of principal stretches and their logarithms in the current basis of the left distortion tensor. It is shown that the “classical” multiplicative decomposition of the total strain gradient into the product of elastic and plastic strain gradients is equivalent to the presentation of total stretches as a product of elastic and plastic stretches.  相似文献   
978.
We reveal a functional diagram, design features of a receiver electrode system, a principle of forming primary informative signals, a technique for synthesizing angular characteristics and estimating indicated errors, channel realization and algorithms of forming output signals of an ionmarking aerodynamic angle and airspeed sensor with logometric informative signals and interpolation processing scheme.  相似文献   
979.
Using the results of numerical modeling of nonstationary gas hydrodynamic working processes in the gas conduit variable section channel when removing and cooling hot gases of different purpose technical plants, an engineering technique has been developed to provide the gas conduit operation under limitations on the flow temperature in the outlet plant section. A multiparametric area of permissible gas conduit operation connecting the characteristics of technical plants, gas conduit and water feeding system is presented.  相似文献   
980.
Electric currents permeate space plasmas and often have a significant component along the magnetic field to form magnetic flux ropes. A larger spatial perspective of these structures than from the direct observation along the satellite path is crucial in visualizing their role in plasma dynamics. For magnetic flux ropes that are approximately two-dimensional equilibrium structures on a certain plane, Grad-Shafranov reconstruction technique, developed by Bengt Sonnerup and his colleagues (see Sonnerup et al. in J. Geophys. Res. 111:A09204, 2006), can be used to reveal two-dimensional maps of associated plasma and field parameters. This review gives a brief account of the technique and its application to magnetic flux ropes near the Earth’s magnetopause, in the solar wind, and in the magnetotail. From this brief survey, the ranges of the total field-aligned current and the total magnetic flux content for these magnetic flux ropes are assessed. The total field-aligned current is found to range from ∼0.14 to ∼9.7×104 MA, a range of nearly six orders of magnitude. The total magnetic flux content is found to range from ∼0.25 to ∼2.3×106 MWb, a range of nearly seven orders of magnitude. To the best of our knowledge, this review reports the largest range of both the total field-aligned current and the total magnetic flux content for magnetic flux ropes in space plasmas.  相似文献   
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