Electrostatic Noise Spectrum at the Electron Cyclotron Frequency and Electromagnetic Emission in the Inhomogeneous Plasma of the Topside Ionosphere

Measurements of the wave emission of the topside ionosphere made onboard the APEX satellite using the electric component of the wave field in the 0.1–10 MHz frequency band are presented. At middle latitudes a wave intensity decrease was observed in the broad-band spectrum of the electrostatic noise at the electron cyclotron frequency. It is shown that a break in the spectrum of electrostatic modes at the electron cyclotron frequency (the absence of the plasma eigen-frequencies) may be a cause of the observed effect. The increase of the intensity at the electron cyclotron frequency in the ionospheric trough and at latitudes above the trough region as compared to middle latitudes may be explained by the capture by plasma irregularities of the electromagnetic emission of the auroral electron fluxes.__________Translated from Kosmicheskie Issledovaniya, Vol. 43, No. 3, 2005, pp. 201–208.Original Russian Text Copyright © 2005 by Izhovkina, Prutensky, Pulinets, Kiraga, Klos, Rothkael.     

Detection of ultrahigh-energy cosmic rays and neutrinos by radio method using artificial lunar satellites

An estimate of the feasibility of the ultrahigh-energy cosmic ray and neutrino detection using a lunar satellite-borne radio receiver is presented. The data obtained in the proposed experiment will make resolving the current contradictions in the ultrahigh-energy cosmic ray spectra measured with the major ground-based instruments possible. Moreover, they will enable us to considerably extend the accessible energy range and to check predictions of various models of the origin of the highest-energy particles in the Universe. At the same time the lunar radio detector provides a means of searching for ultrahigh-energy neutrinos with a high sensitivity combined with a very large target effective mass.     

Mechanisms of generation and dynamics of HF and LF emissions in the experiments with electron beams injected into the earth’s ionosphere

Mechanisms of generation and dynamics of HF and LF emissions related to an electron beam injection from a spacecraft into the ionosphere are studied. The choice of the source and region of emission is substantiated. The plasma current neutralizing the spacecraft charge and the region of spatial charge in the vicinity of the spacecraft are chosen. Mechanisms of the generation of HF and LF emissions are proposed and their characteristics are determined. For the considered ranges of emission, the explanation of the facts related to the difficulties in interpretation of the amplitude value observed experimentally and the behavior of its envelope are presented. It is shown that the results obtained in this work agree well with the data of the conducted experiments.     

Numerical simulation of effects of the August 11, 1999 solar eclipse in the outer ionosphere

The results of a numerical simulation of such parameters of the topside ionosphere as concentration N _e and temperature T _e of electrons, and concentration n(H⁺) and fluxes along the magnetic field lines Φ(H⁺) of H⁺ ions at an altitude of ～2000 km for the conditions of the August 11, 1999 solar eclipse are presented. The calculations were performed using the Global Self-consistent Model of the Thermosphere, Ionosphere, and Protonosphere of the Earth (GSM TIP). It is shown that during the eclipse, in addition to a region of decreased values of T _e in the Northern Hemisphere and in the magnetically conjugate region in the Southern Hemisphere, regions of electron heating emerge in both hemispheres. Simultaneously, an extended region of decreased values of N _e comes into existence and moves behind the Moon’s shadow. Regions with decreased (down to ～30%) and enhanced (up to ～50%) concentrations of H⁺ ions are detected in the global distribution of these ions.     

US and Soviet planetary exploration The next step is Mars, together

Soviet General Secretary Gorbachev has proposed a joint US-Soviet programme to explore the planet Mars. The authors argue that there is considerable advantage to be gained from such a programme for both countries and for all nations on Earth. They trace the history of the US and Soviet space programmes and of cooperation between the two nations, focusing particularly on activities relating to Mars. Robotic Mars exploration is already technically possible and could take place in the 1990s, and a first step towards manned exploration could be the writing of a development and flight plan aiming for the first decade of the 21st century.     

Autoignition of fuel-oxidizer mixtures in microgravity

The paper examines the limitations of quasi-steady autoignition theory in providing information needed for the characterization of autoignition temperature fields. Time-dependent autoignition theory is then utilized to examine the autoignition behavior of a reactive system where both wall catalysis and gas phase kinetic rates are significant. It is found that a diverse range of space-time temperature-composition-pressure histories is possible, depending on the system's thermo-kinetic characteristics.     

褶皱结构成形时的形状偏差计算

解决了褶皱结构成形时相邻的平行四边形平面元素之间连接区棱的修圆半径值预测问题。把毛坯模拟成薄板，定义了平行四边形平面元素的边界条件，采用能量法导出挠度和力函数的非线性微分方程组，利用积分－差分法实现其数值解，并提供计算结果和分析应力－应变场。采用的计算方法可用于研究毛坯的刚度参数和工艺参数对褶皱结构的形状影响。     

用薄板等积变换方法制造起伏构造的工艺问题研究(英文)

研究了用于夹层壁板的新型轻质芯材的制造问题。该种芯材是一种可改变平面方向的褶皱构造。采用薄板等积变换通过局部弯曲而不拉伸材料的方法制造该种芯材已成为可能。其主要难点在于 ,必须实现沿复杂的展开图上所有的画线同时弯曲。现借助于成形过程中使原来的构形组件变形解决其造型问题。本文提出的工艺方法可用于不同材料的深度起伏构造制造 ,如金属薄板和纸等。     

A concept of increasing efficiency for ramjet operation

The vortical mixing concept in the ramjet channel is analyzed. The results of simulating the gasodynamic scheme permit the concept of increasing efficiency for ramjet operation to be substantiated.