关于互斥方案决策问题的研究

互斥方案决策时，运用净现值和内部收益率指标，经常遇到结论相矛盾的情况，本文主要应用方案重复法和投资增额评价法解决这一问题。     

大气环境监测卫星星载激光雷达二氧化碳遥感反演方法及精度验证

目前卫星被动遥感二氧化碳存在空间覆盖不足、时空分辨率不够、地球两极和夜间缺少数据等问题，对二氧化碳的源汇研究带来很大的不确定度，同时也制约着利用卫星遥感温室气体探究全球变化。2022年4月我国发射了全球首颗搭载主动激光雷达探测二氧化碳的卫星-大气环境卫星。其上搭载了的气溶胶和碳探测激光雷达(ACDL)，利用1 572 nm的两束激光，可以反演干空气中加权平均的二氧化碳柱浓度。初步与香河站(全球碳柱总量观测网)站点比对的平均偏差为0.48 ppm，Sodankyla(全球碳柱总量观测网)站点的比对的平均偏差为0.8 ppm，精度超过被动遥感卫星。     

Some new applications of the generalized problem of two fixed centers

A generalized problem of two fixed centers and its limiting version is considered. New possible applications of this problem are obtained. Using a symmetric version of the problem, the external field of gravitation is approximated. The limiting version approximates the inner field.     

前苏联卫星遥感技术概况及其应用

该文介绍前苏联航天遥感系统的概况及其应用。     

Studies of substorm on March 12, 1991: 2. Auroral electrons. Acceleration,injection, and dynamics

In the first part of this study of the substorm of March 12, 1991, the space-time structure of substrorm disturbance and dynamics of auroral ions were considered. This second part presents an analysis of measurements of auroral electrons onboard the CRRES satellite. It is demonstrated that enhancements of the electron flux (injections) during large-scale and local dipolarizations of the magnetic field are determined by a combination of field-aligned, induction, and betatron mechanisms of acceleration with an effect of displacement of the drift shells of particles. The relative contributions of these mechanisms in relation to the energy of auroral electrons are determined.     

Statistical investigation of Heliospheric conditions resulting in magnetic storms: 2

This work is a continuation of investigation [1] of the behavior of the solar wind’s and interplanetary magnetic field’s parameters near the onset of geomagnetic storms for various types of solar wind streams. The data of the OMNI base for the 1976–2000 period are used in the analysis. The types of solar wind streams were determined, and the times of beginning (onsets) of magnetic storms were distributed in solar wind types as follows: CIR (121 storms), Sheath (22 storms), MC (113 storms), and “uncertain type” (367 storms). The growth of variations (hourly standard deviations) of the density and IMF magnitude was observed 5–10 hours before the onset only in the Sheath. For the CIR-, Sheath-and MC-induced storms the dependence between the minimum of the IMF B _z-component and the minimum of the D _st -index, as well as the dependence between the electric field E _y of solar wind and the minimum of the D _st -index are steeper than those for the “uncertain” solar wind type. The steepest D _st vs. B _z dependence is observed in the Sheath, and the steepest D _st vs. E _y dependence is observed in the MC.     

The concept of a Space-Space interferometer for observations in mm and sub-mm wavebands

At present, space radio astronomers and engineers study the prospects of design of the second-generation ground-space interferometers for astrophysical research with the microsecond angular resolution of sources. The implemented Japanese VSOP project (1998–2003) and the Russian Radioastron project (under preparation for space flight) are related to the first generation. In this paper, the ideology and configuration of the Space-Space interferometer are considered. It would allow one to obtain principally new capabilities: to exclude the Earth’s atmosphere influence, to realize a quasi-phase-stable interferometer, and to remove the problems of electromagnetic compatibility with other services. Moreover, a capability will appear to carry out preliminary correlation processing onboard the spacecraft due to achievement of small residual uncertainties in signal delay and frequency and, owing to this, to realize onboard data compression in order to transmit data to the Earth by usual space communication channel.     

前苏联洲际弹道导弹P-7控制系统研制历程

本文叙述了前苏联第一种洲际弹道导弹P - 7弹上控制系统的前期研制和试验历史 ,介绍了燃料消耗控制、视速度调节、法向和横向控制这些子系统的构成原理     

Dynamics of a gyrostat satellite with the vector of gyrostatic moment in the principal plane of inertia

Dynamics of a gyrostat satellite moving along a circular orbit in a central Newtonian field of force is investigated. In a particular case, when the gyrostatic moment vector lies in one of the satellite’s principal central planes of inertia, all positions of equilibrium are determined, and the conditions of their existence are analyzed. Also determined are bifurcation values of dimensionless parameters, at which the number of equilibrium positions changes. As a result of analysis of the generalized energy integral, for each equilibrium orientation the sufficient conditions of stability are derived. Evolution of the regions where the sufficient conditions of stability are valid is investigated under variation of the system’s dimensionless parameters.     

Intermittency of solar wind density fluctuations and its relation to sharp density changes

The paper presents the study of turbulent properties of the solar wind plasma, namely, the intermittency of fluctuations of the solar wind ion flux in the earlier unexplored region of comparatively high frequencies (0.01–1 Hz). Special attention is given to a comparison of intermittency for solar wind observation intervals containing sharp (shorter than 10 min) and high-amplitude (greater than 20%) changes of the ion flux to intervals without such changes. The solar wind observation intervals containing sharp changes of the flux are found to be essentially more intermittent than the intervals of quiet solar wind. Such a comparison allows one to reveal the fundamental difference in turbulent properties of the solar wind depending on the presence or absence of sharp boundaries in plasma structures.     

自卸车驱动桥壳的过盈接触分析

用有限元数值模拟的方法研究了一款自卸车驱动桥壳的过盈接触问题,分别就外部载荷和桥壳的厚度变化对过盈接触的影响做了分析,根据分析的结果,优化了桥壳和半轴套管的公差配合,使过盈量在安全的区间内.     

超高强铝合金LC9的超塑性研究

工业牌号超高强铝合金LC9经过两种不同方式的预处理后,在一定的温度和应变速率范围内呈现出良好的超塑性。材料经过形变热处理(TMT)后,在最佳超塑性条件下拉伸(T_(TMT)=515℃,ε_(TMT)=1.66×10~(-3)s~(-1)),获得很高的延伸率δ_(TMT)=1300％,低的流变应力σ_(TMT)=1.7MPa和高的应变速率敏感性指数m_(TMT)=0.66。经过简单锻造预处理后,在最佳超塑条件下(T_f=405℃、ε_f=1.66×10~(-3)s~(-1)),材料仍能获得δ_(f)=380％、σ_(f)=16MPa、m_(f)=0.3。TMT预处理中,η相粒子分布状态对获取微细组织起着决定性作用,η相的回溶降低了材料的空洞敏感性,抑制试样早期断裂。经过两种方式预处理的试样超塑性断裂形式分别为空洞型失稳断裂和颈缩型稳定断裂。     

First results of investigating the space environment onboard the Universitetskii-Tatyana satellite

The complex of scientific pay load installed onboard the research and educational Universitetskii-Tatyana microsatellite of Moscow State University is described. The complex is designed to study charged particles in the near-earth space and ultraviolet emissions of the atmosphere. Data of the measurements of charged particle fluxes in the microsatellite orbit are presented, spectra are calculated, and the dynamics of penetration boundaries for protons of solar cosmic rays (SCR) during geomagnetic disturbances in 2005 is investigated. Intensities of the ultraviolet emission are measured in the entire range of variation of the atmospheric irradiation, as well as intensities of auroras in the polar regions of the Northern and Southern hemispheres. The experimental data on flashes of ultraviolet radiation (transient light phenomena in the upper atmosphere) are considered, and some examples of oscillograms of their temporal development and their distribution over geographical coordinates are presented. Original Russian Text ? V.A. Sadovnichy, M.I. Panasyuk, S.Yu. Bobrovnikov, N.N. Vedenkin, N.A. Vlasova, G.K. Garipov, O.R. Grigorian, T.A. Ivanova, V.V. Kalegaev, P.A. Klimov, A.S. Kovtyukh, S.A. Krasotkin, N.V. Kuznetsov, S.N. Kuznetsov, E.A. Muravyeva, I.N. Myagkova, N.N. Pavlov, R.A. Nymmik, V.L. Petrov, M.V. Podzolko, V.V. Radchenko, S.Ya. Reisman, I.A. Rubinshtein, M.O. Riazantseva, E.A. Sigaeva, E.N. Sosnovets, L.I. Starostin, A.V. Sukhanov, V.I. Tulupov, B.A. Khrenov, V.M. Shakhparonov, V.N. Sheveleva, A.V. Shirokov, I.V. Yashin, V.V. Markelov, N.N. Ivanov, V.N. Blinov, O.Yu. Sedykh, V.P. Pinigin, A.P. Papkov, E.S. Levin, V.M. Samkov, N.N. Ignatiev, V.S. Yamnikol, 2007, published in Kosmicheskie Issledovaniya, 2007, vol. 45, No. 4, pp. 291–305.     

Possible role of electrostatic potential in formation of sharp boundaries of small-scale and middle-scale solar wind structures

Sharp boundaries of small-scale and middle-scale structures of the solar wind are an essential part of a turbulized solar wind. Such boundaries are observed near the Earth’s orbit as sharp and large-amplitude changes of parameters (in particular, ion density) of the solar wind. In this paper, the observed phenomena are briefly described, and an account of their basic properties and specific features is given. Using the kinetic approach, a possible theoretical mechanism is suggested in order to explain some peculiarities in the formation of these structures.     

On the planar inertial motion of a system of three coupled bodies

Numerous papers are devoted to studying the motion of a system (coupling) of two bodies in the Earth’s satellite orbit ([1–4] and others). The problem on the planar inertial motion of three bodies, coupled by a non-extensible weightless string having the form of an unfastened chain, is considered in the paper. Such a configuration can be represented, for example, by a system of two coupled spacecraft rotating around their common center of mass (in order to simulate the gravity force) in long-term space missions, when the third body (the lift) is located on a connecting cable. The bodies are considered to be the material points (particles).     

Navigation of a space bunch under conditions of its rotary motion

The properties of a tethered space system (bunch) in the mode of rotational motion are used in determination of the parameters of the location and orientation of the end vehicles of the bunch by the method with the simplest possible instrumental implementation.     

The motion of a particle in perturbed field of an attracting center

The integrable case of the perturbed two-body problem is considered. The perturbation is determined by the potential of a special form. The L-matrix is chosen in such a way that partial separation of variables should take place in regular coordinates. Integration of the equations of motion of the problem under consideration is made. The solutions are expressed through elliptic functions. The orbits for various cases are constructed. The results of numerical calculations are given.