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331.
332.
李伟梁 《郑州航空工业管理学院学报(管理科学版)》2008,26(3):86-90
在社区各类资源中,物质资源最为重要,它是社区建设的物质基础和前提保障。社区物质资源的短缺极大地制约了社区建设和发展。因此,在建设和谐社区过程中,必须不断加强社区物质资源的整合。社区物质资源整合机制的构建主要包括社区资金的多元筹集机制和驻社区单位的资源共享机制。 相似文献
333.
“六性”、“七化”与“一品”——全国高职高专学报走向再探索 总被引:3,自引:0,他引:3
潘世东 《西安航空技术高等专科学校学报》2008,26(6):70-73
通过分析高职高专学报生存发展的现状和面临的主要问题,提出了高职高专学报的宗旨定位、作者定位、读者定位和特色定位;结合学报学会组织的功能和使命及高职高专学报的发展方向,归结出了“六性”、“七化”与“一品”的奋斗目标。 相似文献
334.
新出现的RISC微处理器提供了超计算能力,采用i860XP超标量微处理器来增强已存在的Transputer系统的性能是一种切实可行的办法,它们构造了一种异构型多处理器系统。本文给出了该系统的设计和性能分析。 相似文献
335.
L.H. Deng B. Li Y.Y. Xiang G.T. Dun 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The mid-term periodicities of polar faculae are studied separately for the total disk, northern and southern hemispheres of the Sun for a time interval from 1951 August to 1998 December. Apart from the 11-year Schwabe cycle which is the fundamental period and is found in all of the three time series, the following prominent results are found: (1) the rotational periodicity of solar activity at high latitudes is approximately from 28 to 32 days; (2) a large number of quasi-periods appearing in low-latitude solar activity (annual variation, 1.3–1.7 years, quasi-biennial oscillation, and 4–5 years) also exist in polar faculae; (3) the periodicities on both hemispheres are not identical. 相似文献
336.
S. Sen A. Mangalam 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(2):617-627
We build a single vertical straight magnetic fluxtube spanning the solar photosphere and the transition region which does not expand with height. We assume that the fluxtube containing twisted magnetic fields is in magnetohydrostatic equilibrium within a realistic stratified atmosphere subject to solar gravity. Incorporating specific forms of current density and gas pressure in the Grad–Shafranov equation, we solve the magnetic flux function, and find it to be separable with a Coulomb wave function in radial direction while the vertical part of the solution decreases exponentially. We employ improved fluxtube boundary conditions and take a realistic ambient external pressure for the photosphere to transition region, to derive a family of solutions for reasonable values of the fluxtube radius and magnetic field strength at the base of the axis that are the free parameters in our model. We find that our model estimates are consistent with the magnetic field strength and the radii of Magnetic bright points (MBPs) as estimated from observations. We also derive thermodynamic quantities inside the fluxtube. 相似文献
337.
《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2020,65(2):756-762
We investigate the relationship between the 5 GHz interstellar scintillation (ISS) and the 15 GHz intrinsic variability of the compact, radio-selected active galactic nuclei (AGN) common to the Microarcsecond Scintillation-Induced Variability (MASIV) Survey and the Owens Valley Radio Observatory blazar flux density monitoring program. As part of this investigation, we also re-examine the reported intrinsic nature of the February 1990 VLA observations of the blazar S5 0716+714. We are also examining the presence of IDV/ISS in the Owens Valley 15 GHz flux density monitoring data. We find a significant relationship between the Owens Valley 15 GHz modulation index and the MASIV modulation index. We also discuss the implications of these findings for RadioAstron. 相似文献
338.
Salvatore Mancuso Alessandro Bemporad 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
We report on the analysis of two fast CME-driven shocks observed with the UltraViolet Coronagraph Spectrometer (UVCS) on board the Solar and Heliospheric Observatory (SOHO). The first event, detected on 2002 March 22 at 4.1 R⊙ with the UVCS slit placed in correspondence with the flank of the expanding CME surface, represents the highest UV detection of a shock obtained so far with the UVCS instrument in the corona. The second one, detected on 2002 July 23 at 1.6 R⊙ with the UVCS slit placed in correspondence with the front of the expanding CME surface, shows an anomalous deficiency of ion heating with respect to what observed in previous CME/shocks observed by UVCS, possibly reflecting the effect of different coronal plasma conditions over the solar cycle. From the two different sets of observations we derived an estimate for the shock compression ratio X, which turns out to be X = 2.4 ± 0.2 and X = 2.2 ± 0.1, respectively, for the first and second event. Comparison between the two events provides complementary perspectives on the dynamical evolution of CME-driven shocks. 相似文献
339.
Volodymyr Kryvdyk 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
Formation of relativistic jets in the magnetosphere of collapsing stars is considered. These jets will be formed in the polar caps of magnetosphere of collapsing star, where the stellar magnetic field increases during the collapse and the charged particles are accelerated. The jets will generate non-thermal radiation. The analysis of dynamics and emission of particles in the stellar magnetosphere under collapse shows that collapsing stars can be powerful sources of relativistic jets. 相似文献
340.
P. Jovanović V. Borka Jovanović D. Borka T. Bogdanović 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
We used a model of a relativistic accretion disk around a supermassive black hole (SMBH), based on ray-tracing method in the Kerr metric, to study the variations of the composite Fe Kα line emitted from two accretion disks around SMBHs in a binary system. We assumed that the orbit of such a binary is approximately Keplerian, and simulated the composite line shapes for different orbital elements, accretion disk parameters and mass ratios of the components. The obtained results show that, if observed in the spectra of some SMBH binaries during their different orbital phases, such composite Fe Kα line profiles could be used to constrain the orbits and several properties of such SMBH binaries. 相似文献