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951.
S. O. Karpenko N. V. Kupriyanova M. Yu. Ovchinnikov V. I. Penkov A. S. Selivanov O. E. Khromov 《Cosmic Research》2010,48(6):517-525
The results of designing the attitude control system of the first Russian nanosatellite TNS-0 no. 1 providing orientation of its longitudinal axis along the local geomagnetic field induction vector are presented. The system
consists of a permanent magnet and two sets of hysteresis rods. The magnetic and geometric parameters of the magnet and rods
are calculated. The influence of the permanent magnet field on the hysteresis rods and mutual influence of the rods in the
case of compact satellite packaging are analyzed. Examples of calculations of transient processes and steady-state angular
satellite motion are presented. 相似文献
952.
The paper discusses a method of designing the neural controller for two-channel control of a technical object by an example of the roll and yaw control depending on deviations, velocities and accelerations of their variation. 相似文献
953.
954.
955.
目的介绍一种在Labwindows/CVI环境下调用Word的实现方法;方法结合具体的实例,实现对Word文档的调用;结果该方法可以按照规定的格式自动生成Word文档;结论提高了软件的效率和自动化程度。 相似文献
956.
The volume finite element in the form of hexahedron with nodal unknowns as components of the displacement vector and stress
tensor has been developed to analyze the shells of revolution. The displacement vector components for the inner point of the
finite element and the components of its stress tensor are expressed through the nodal unknowns using the method of vector
and tensor fields interpolation by the trilinear shape functions; that provides taking into account the finite element displacement
as a whole solid. The variational principle in a mixed formulation is applied to form the matrix of hexahedron deformation.
The efficiency of the proposed method for approximating the values being sought as vector and tensor fields in comparison
with the traditional method for approximating the values being sought as scalar fields is confirmed by a numerical example. 相似文献
957.
958.
A. Yu. Liss 《Russian Aeronautics (Iz VUZ)》2012,55(2):136-143
We present the materials, which substantiate the application of a rather simple approximate method of accounting for disturbances of the airflow around the helicopter main rotor blades; in this case, the disturbances are caused by vortices that come down from the blade ends. It is shown that these disturbances influence significantly the varying blade loads. 相似文献
959.
We present the results of investigation of the dynamics of (99942) Apophis asteroid, which will undergo a very close encounter
with the Earth on April 13, 2029. The region of possible motions of the asteroid is considered on the time interval (2004,
2040). In addition, it is shown that an increase of the observational interval (2004, 2006) until 2008 allowed us to reduce
significantly the area of possible motions. All investigations were performed by numerical methods with the help of algorithms
and software developed by us in the environment of parallel programming using the SKIF Cyberia multiprocessor computer of
the Tomsk State University. 相似文献
960.
现代化导弹结构设计方式对产品研制过程中的海量数据管理要求极为严格,必须实施科学有效的产品数据管理模式.本文介绍了VPM项目实施概况,探讨了基于VPM环境下的武器系统结构设计过程.同时,给出了一个在VPM环境下,用CATIA创建某型武器系统头舱,对其进行全产品周期设计、发布的过程. 相似文献