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71.
The RESIK is a high sensitivity, uncollimated bent crystal spectrometer which successfully operated aboard Russian CORONAS-F solar mission between 2001 and 2003. It measured for the first time in a systematic way solar soft X-ray spectra in the four wavelength channels from 3.3 Å to 6.1 Å. This range includes characteristic strong lines of H- and He-like ions of K, Ar, Cl, Si, S and Al in the respective spectral channels. A distinguishing feature of RESIK is its possibility of making reliable measurements of the continuum radiation in flares. Interpretation of line and the continuum intensities observed in vicinity of respective strong lines provides diagnostics of plasma temperature and absolute abundances of K, Ar, Cl, S, Si and Al in several flares. We analyzed the observed intensities of spectral lines and the nearby continuum using the CHIANTI v5.2 atomic data package. A specific, so-called “locally isothermal” approach has been used in this respect allowing us to make not only flare-averaged abundance estimates, but also to look into a possible variability of plasma composition during the course of flares.  相似文献   
72.
We report on the results of a continuing study of the photon luminescence of the Moon induced by Galactic Cosmic Rays (GCRs) and space radiation from the Sun, using the Monte Carlo program FLUKA. Understanding the space radiation environment is critical to future exploration of the Moon, and this includes photons. The model of the lunar surface is taken to be the chemical composition of soils found at various landing sites during the Apollo and Luna programs, averaged over all such sites to define a generic regolith for the present analysis. This surface model then becomes the target that is bombarded by Galactic Cosmic Rays (GCRs) and Solar Energetic Particles (SEPs) or Solar Particle Events (SPEs) above 1 keV in FLUKA to determine the photon fluence albedo produced by the Moon’s surface when there is no sunlight and Earthshine. The result is to be distinguished from the gamma-ray spectrum produced by the radioactive decay of radiogenic constituents lying in the surface and interior of the Moon. From the photon fluence we derive the spectrum which can be utilized to examine existing lunar spectral data and to aid future orbiting instrumentation in the measurement of various components of the space-radiation-induced photon luminescence present on the Moon.  相似文献   
73.
无网格方法关于导数计算的程序验证   总被引:1,自引:1,他引:0  
为了提高无网格方法对空间导数的数值计算能力,提出并论证了新的适用于直角坐标系、柱坐标系和球坐标系的空间导数无网格算法。基于数值解与理论解的对比分析,对数值误差和收敛性进行了后验评估。评估结果表明:该算法对函数和导数的估计均为2阶精度,支撑域尺度对数值误差的大小有一定影响,但不影响数值计算的精度等级。在离散尺度h为0.01的条件下,对所选函数及其导数的数值计算相对误差不大于0.65%。   相似文献   
74.
在当前的新课程改革中,教师是课程实施的建设者和协商者,同时也是教学绩效的责任主体,必须参与到学校的课程领导中来,本文基于此来谈教师的课程领导。具体分析了教师领导新课程的可能性,并给出教师课程领导的相关策略,以期对教师课程领导发展有所裨益。  相似文献   
75.
对是民磁脉冲波方程的数学征物理模型之初值问题进行了研究,应用细致的先验估计,建立了该问题解的整体存在性与唯一性,并对解趋于│x│→∞处的渐近性态做了讨论。  相似文献   
76.
The Geospace Double Star Project (DSP) consists of two small satellites operating in the near-earth equatorial and polar regions, respectively. The goals of DSP are: (1) to provide high-resolution field, particle, and wave measurements in some important near-earth active regions which have not been covered by current ISTP missions, such as the near-earth plasma sheet and its boundary layer, the ring current, the radiation belts, the dayside magnetopause boundary layer, and the polar region; (2) to investigate the trigger mechanisms of magnetic storms, magnetospheric substorms, and magnetospheric particle events,as well as the responses of geospace storms to solar activities and interplanetary disturbances; (3) to set up the models describing the spatial and temporal variations of the near-earth space environment.To realize the above goals, the equatorial satellite TC-1 and the polar satellite TC-2 will accommodate, respectively, eight instruments on board. TC-1was launched successfully in December 2003 while the polar satellite (TC-2)will be launched in July 2004. The orbit of the equatorial satellite TC-1 consists of a perigee at 550 km, an apogee at 60 000 km, and an inclination of about 28.5; while the orbit of the polar satellite will have a perigee of 700 km, an apogee of 40 000 km, and an inclination of about 90. The two satellites will take coordinated measurements with Cluster Ⅱ and will first form a "six-point exploration" in geospace.The operational status of TC-1 are introduced in this paper.  相似文献   
77.
时间、空间及运动的测量原理与时间和空间的理论   总被引:1,自引:1,他引:1  
林金 《宇航学报》2000,21(3):13-23
本文从分析时间、空间及运动的测量机理出发建立的时间和空间理论。导出了建立在电磁信号单向传递的相对性原理基础上的时空对称的新加里略变换,并证明了麦克斯韦方程对新加里略变换的协变性。阐明了光速不变原理和洛伦兹变换的物理意义和实质。引进了两套自治的速度定义,对应两套自治的变换。讨论了超光速运动的测量机制,相对运动特征出现负值是超光速运动的特征,导出了对应超光速运动的新加里略变换和洛伦兹变换。  相似文献   
78.
新一代多光谱扫描仪方案设计是以某单位拟议的技术要求为依据开展的。文章简要介绍了方案设计中的设计思想、系统基本原理和关键技术原理等。该遥感器已于1999年10月完成原理样机研制,获得了满意的结果。  相似文献   
79.
The progress on Chinese Space Solar Telescope (SST) in 2002-2004 is introduced. The documentations on plans and outlines based on the standards of Chinese aerospace industry for SST mission has been fulfilled. The key technical problems of SST satellite platform and payloads are tackled during pre-study stage of the mission. The laboratory assembly and calibration of the main optical telescope of 1.2 m spherical mirror and 1 m plain mirror have been carried out with the accuracy of λ/40 and λ/30, respectively. The prototype at 17.1 nm for extreme ultraviolet telescope is under development and manufacture with a diameter of 13 cm. Its primary and secondary mirrors have a manufacturing error of 5nm with a roughness degree of less than 0.5 nm and a multiplayer reflection factor of better than 20%. The on-board scientific data processing unit has been developed. Prototypes for other payloads such as H and white light telescope, wide band spectroscopy in high energy and solar and interplanetary radio spectrometer have been developed accordingly.  相似文献   
80.
Their brief report presents the advances of the magnetospheric physics researches in China during the period of 2004-2006. During the past two years, China-ESA cooperation DSP (Double Star Program) satellites were successively launched. In addition, China also participated in the scientific research of ESA's Cluster mission. The DSP and Cluster missions provide Chinese space physicists high quality data to study multiscale physical process in the magnetosphere. The work made based on the data of DSP is presented in the paper of "Progress of Double Star Program" of this issue.  相似文献   
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