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361.
A. V. Tavrov O. I. Korablev A. V. Rodin I. I. Vinogradov A. Yu. Trokhimovsky A. Yu. Ivanov L. V. Ksanfomaliti D. A. Orlov 《Cosmic Research》2011,49(2):99-109
In order to observe exoplanets we propose a space-based achromatic stellar coronagraph combined with a 0.8–1.5 m telescope.
We develop an achromatic common path interferometer for observing an exoplanet (a faint off-axis source) on the background
of a hoste star (bright axial source). An image of the star and its copy acquire an achromatic phase shift by 180° and interfere
in antiphase. The achromatic phase shift is caused by geometric phase in the scheme of a three-dimensional interferometer.
The interference process divides spatially the dark and light fields of the star image redirecting them to the opposite sides
of a beam splitter. The interference process does not weaken the image of a planet, with equal intensities it is redirected
to both sides of a beam splitter. The suggested scheme of common path interferometer ensures mechanical stability. The background
signal is experimentally demonstrated to be reduced by six orders of magnitude. 相似文献
362.
I. A. Galiullin 《Cosmic Research》2011,49(2):175-178
The constraints imposed on parameters of a force field and of a symmetrical gyrostat in it are determined, at which regular
precession of this gyrostat demonstrate Lyapunov stability (or, respectively, instability). 相似文献
363.
Selected micro- and nano-systems developed recently at the Physical Electronics Laboratory of ETH Zurich are reviewed: (i) a fluxgate microsystem for detection of the Earth's magnetic field; (ii) a capacitive chemical sensor microsystem for detection of volatile organic compounds in air; and (iii) a parallel scanning AFM chip. The micro- and nano-systems combine sensor structures and readout circuitry on a single chip and are fabricated using industrial CMOS technology in combination with post-processing micromachining and film deposition 相似文献
364.
Possible consequences of collisions of natural cosmic bodies with the Earth’s atmosphere and surface are described. The methodological
basis of classification of consequences is the solution of meteor physics equations characterizing the trajectory of a body
in the atmosphere, namely, the dependence of the body’s velocity and mass on the flight altitude. The solution depends on
two dimensionless parameters characterizing the drag altitude and the role of mass loss by a meteoroid during its motion in
the atmosphere. Depending on values of these parameters, the degree of effect on the planetary surface considerably changes.
In particular, the conditions of cratering and meteorite fall on the planetary surface are obtained. The results are presented
in a simple analytical form. They quite match to the real events considered in the paper. Recommendations are given on further
investigations into the important problem of interaction of cosmic bodies with planetary atmospheres. 相似文献
365.
B. A. Antuf’ev 《Russian Aeronautics (Iz VUZ)》2008,51(3):227-231
A problem on low vibrations of a thin spherical shell is considered. A solid of finite dimensions is discretely attached to the shell by means of an elastic rod system. The calculation examples are presented. 相似文献
366.
The derivation of parametric equations for a limiting surface in the space of internal forces and moments that act in the rod cross-sections, using the basic concepts of plasticity theory and conventional hypotheses of the rod theory, is presented. The plastic properties of rod material are described by the Mises criterion. A case of small displacements and strains under static simple loading is considered. The results of solving a number of problems of constructing limiting curves in the planes of internal forces and moments are given. 相似文献
367.
卢兴猷 《南京航空航天大学学报(英文版)》1998,(1)
香港工商企业的质量管理大部分都采用西方的质量管理概念。每当范畴扩展到建立人的优质思想和意识时,便遇到不少困难,基于上述问题,作者进行了一系列的研究,希望了解‘文化’与‘优质管理’之间的关系,并将中国的优良文化传统应用于现代质量管理之中。研究结果显示,‘管理哲学’是重要的一环,而我国的哲学极为丰富,作者借此文章,希望引起更多中国人在这方面的兴趣,从而进行更深入地研究和推广。 相似文献
368.
M Durante T Kawata T Nakano S Yamada H Tsujii 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1998,22(12):1653-1662
We report measurements of chromosomal aberrations in peripheral blood lymphocytes from cancer patients undergoingradiotherapy treatment. Patients with cervix or esophageal cancer were treated with 10 MV X-rays produced at a LINAC accelerator, or high-energy carbon ions produced at the HIMAC accelerator at the National Institute for Radiological Sciences (NIRS) in Chiba. Blood samples were obtained before, during, and after the radiation treatment. Chromosomes were prematurely condensed by incubation in calyculin A. Aberrations in chromosomes 2 and 4 were scored after fluorescence in situ hybridization with whole-chromosome probes. Pre-treatment samples were exposed in vitro to X-rays, individual dose-response curves for the induction of chromosomal aberrations were determined, and used as calibration curves to calculate the effective whole-body dose absorbed during the treatment. This calculated dose, based on the calibration curve relative to the induction of reciprocal exchanges, has a sharp increase after the first few fractions of the treatment, then saturates at high doses. Although carbon ions are 2–3 times more effective than X-rays in tumor sterilization, the effective dose was similar to that of X-ray treatment. However, the frequency of complex-type chromosomal exchanges was much higher for patients treated with carbon ions than X-ray. 相似文献
369.
H.N. Wang Y.M. Cui R. Li L.Y. Zhang H. Han 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,42(9):1464-1468
Nowadays operational models for solar activity forecasting are still based on the statistical relationship between solar activity and solar magnetic field evolution. In order to set up this relationship, many parameters have been proposed to be the measures. Conventional measures are based on the sunspot group classification which provides limited information from sunspots. For this reason, new measures based on solar magnetic field observations are proposed and a solar flare forecasting model supported with an artificial neural network is introduced. This model is equivalent to a person with a long period of solar flare forecasting experience. 相似文献
370.
N Desai H Wu K George S R Gonda F A Cucinotta 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(6):1362-1367
Space flight results in the exposure of astronauts to a mixed field of radiation composed of energetic particles of varying energies, and biological indicators of space radiation exposure provides a better understanding of the associated long-term health risks. Current methods of biodosimetry have employed the use of cytogenetic analysis for biodosimetry, and more recently the advent of technological progression has led to advanced research in the use of genomic and proteomic expression profiling to simultaneously assess biomarkers of radiation exposure. We describe here the technical advantages of the Luminex(TM) 100 system relative to traditional methods and its potential as a tool to simultaneously profile multiple proteins induced by ionizing radiation. The development of such a bioassay would provide more relevant post-translational dynamics of stress response and will impart important implications in the advancement of space and other radiation contact monitoring. 相似文献