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1.
高校CIS策划与设计的方法研究   总被引:2,自引:0,他引:2  
高校CIS策划与设计,是CIS的理念与技法在高校教育活动中的运用。高校为吸引国内、国际教育人才,争取优秀学生,就需要进行形象宣传与推广。在资讯越来越发达的今天,高校以具备一定的教育理念、视觉形象规范化的品牌形象出现将成为新时期及教育发展的必然,把高校作为一个品牌来经营应是高校未来发展的趋势之一。  相似文献   

2.
数控机床结合部刚度的计算方法研究   总被引:1,自引:0,他引:1  
现代机床日益向高速、高加速、高效、高精度和大型化、集成化发展,其动态特性的优劣,将直接影响机床的加工性能。论文对影响机床结构建模精度的关键部位——结合部的国内外研究现状进行了综述,分析了各种当前普遍使用的建模方法的优缺点。着眼于获得可用于设计阶段结构优化和性能预测的结合面刚度的计算方法,论文提出了一种基于结合部本构关系的数控机床结合部刚度的研究方法,实例证明这种将实验方法、数值方法和理论方法综合运用的研究思想是实用可行的。  相似文献   

3.
The bursts of long-wave radio emission in the 100–1500 kHz frequency band detected onboard the INTERBALL-1 satellite during strong chromosphere solar flares in 2000 are analyzed. The bursts exhibit large amplitude and duration. A comparison of the bursts with phenomena in the optical, x-ray, and radio bands is carried out.  相似文献   

4.
Within the framework of the circular restricted three-body problem a family of inverse periodic orbits around the two attracting bodies (the Egorov’s family) and families generated by it at the 1:1, 2:1, and 3:1 resonances for three-dimensional orbits in the Sun-Earth and Earth-Moon systems are considered. Their relationship with families generated by orbits around the libration points L 1, L 2 and L 3 is investigated. One of the families contains periodic solutions that seem promising as possible orbits for the space radio telescope of the Millimetron project.  相似文献   

5.
Nose structures are objects formed by H+ particles penetrating into the inner magnetosphere [1, 2]. We present the results of experimental studies and numerical modeling of the nose structures. Statistical processing of the observations of nose structures in 1997 by the ION instrument onboard the Interball-2 satellite at heights of 10000–15000 km demonstrates that the probability of formation of the nose structures under quiet magnetic conditions (with current values K p = 0–1) in the nighttime sector of the magnetosphere is 90%. The probability of observation of the nose structures in the daytime sector equals 50% at the current value K p = 0–1, and the correlation between the observations of nose structures and K p can be improved (up to 75%) if the K p index is taken 6 h before the observed events. It is shown that nose structures are a characteristic feature not only of the substorm processes but also of quasi-stationary phenomena in the quiet magnetosphere. The nose structures observed in magnetically quiet periods are called stationary nose structures in this work. By modeling drift trajectories for protons, it is shown that the stationary nose structures are formed in all sectors of the MLT. The stationary nose structures observed by the ION instrument are modeled in the night, morning, and daytime sectors of the MLT. The relation between the stationary nose structures and ion spectral gaps is considered.  相似文献   

6.
We present the results of experimental studies of high frequency (with periods of seconds and tens of seconds) and low frequency (with periods of minutes and tens of minutes) large variations of the ion flux and magnetic field magnitude in the magnetosheath. It is shown that, on average, the relative amplitudes of these variations are approximately two times higher than similar values characteristic for the undisturbed solar wind. The averaged spatial profile of these values and their variations across the magnetosheath is obtained, as are the dependencies of normalized plasma fluxes and their variations on the place of entrance of a given plasma element into the magnetosheath. Using one particular example, a good coincidence between the time profiles of ion fluxes measured aboard two spacecraft separated by a distance of 10R E along the magnetosheath is demonstrated.  相似文献   

7.
广西百色市物流基地建设探究   总被引:2,自引:0,他引:2  
经过实地调研,文章分析了广西百色市物流基地建设存在的问题,并结合其实际情况,提出相应的解决对策。  相似文献   

8.
We present the results of an experimental investigation of the nature of noise objects on CCD arrays of the units of determination of star coordinates (BOKZ) functioning onboard the Yamal geosynchronous satellite beginning in 1999.  相似文献   

9.
高职高专教学方法和手段改进实践一瞥   总被引:2,自引:0,他引:2  
高职高专的教学方法和手段应是:在实践中教学,在教学中实践,突出实践,运用传统教学和多媒体教学相结合的方式,努力提高学生的综合素质能力和上岗的适应、动手能力。  相似文献   

10.
武新 《中国航天》2007,(6):6-10
2007年5月14日0时01分,我国在西昌卫星发射中心用长征三号乙运载火箭成功地将尼日利亚通信卫星一号送上太空。  相似文献   

11.
Variations of turbulence properties of the plasma sheet during geomagnetic substorms are investigated using observations of the INTERBALL Tail Probe satellite. The periods are chosen when the satellite was inside the plasma sheet. Fluctuations of the plasma bulk velocity across the plasma sheet are studied for the growth, expansion, and recovery phases of geomagnetic substorms on October 14, 1997; October 30, 1997; and December 16, 1998. It was demonstrated that the level of turbulence increases considerably after the onset of the substorm expansion phase and slowly decreases nearly to the presubstorm level later. The correlation times of plasma fluctuations in the Z-direction are estimated, and diffusion coefficients in the Z-direction are calculated.  相似文献   

12.
近空间飞行器成为各国近期研究的热点(上)   总被引:18,自引:0,他引:18  
近空间(Nearspace)通常是指20~lOOkm的高空,其下面的空域(20km以下)是传统航空器的主要运行空间,其上面的空域(100km以上)是航天器的运行空间。近空间飞行器是指运行在近空间范围的飞行器。由于技术和认识上的原因,近空间的战略价值直到最近才引起各国的重视。因此。近空间飞行器成为各国近期研究的热点。美国、俄罗斯、欧洲、韩国、英国、  相似文献   

13.
14.
利用2012年-2014年PS32雨滴谱仪逐分钟的雨滴谱资料,采用Gamma分布拟合的方法,归纳总结出本地化的Z-I关系,再利用变分法进行校准,获得适用于实际业务需要的本地化Z-I关系。将改进后的Z-I关系应用于本地雷达降水估算和预报,从2012年-2014年年所有降水天气过程中选取12个降水天气过程作为检验样本个例,结果表明:利用雨滴谱仪和雨量自动站资料进行Z-I关系本地化,提高了雷达降水估算中雨量的估算精度,较雷达自带降水估算产品更好地反映了降水的空间分布。  相似文献   

15.
Space systems are essential to the global economy and security. The possibility of disruptions arising from competition between the United States and China through the testing and deployment of weapons in space has led to concerns over an incipient space arms race that would threaten satellites, leading to international calls for a space arms control treaty. The paper presents a rationalist theory analysis on the lack of progress in establishing such a treaty, identifying the United States' position of primacy in the global order and its preeminence in space as a primary cause.  相似文献   

16.
Lyubimov  G. P.  Tulupov  V. I. 《Cosmic Research》2003,41(1):19-27
The enhancements of solar protons with an energy of more than 30 MeV, originating from flares in one active region and observed simultaneously aboard three spacecraft Vega-1, 2 and Prognoz-10 in July 1985, are analyzed and approximated in this work by using the reflection model [2]. The numerical values of several physical parameters (the parameters of distribution of solar cosmic ray (SCR) particles inside heliosphere traps, the coefficients of trap transparency) that are not observed by direct measurements are estimated.  相似文献   

17.
18.
The problem of attitude oscillations of a satellite with a small dynamic asymmetry in the plane of the orbit leads to a system degenerate to the fifth order from the point of view of the method of averaging. An explicit expression for the dominant term is obtained by integration in the complex plane. The recurrence procedure of calculating the higher approximations of the method of averaging is considered, as well as an approach to the analysis of the structure of derived expressions.  相似文献   

19.
The paper is devoted to searching for a possible phenomenon of the gravitational lensing of cosmic gamma-ray bursts on celestial bodies of a globular cluster type (mesolensing). If this phenomenon takes place, gamma-ray bursts should have light curves with two or three similar components whose spectra are identical. These components are separated in time by a few seconds. Using a statistical method developed for comparing the components, we have found in the BATSE catalog 11 candidates of gamma-ray bursts with mesolensing for the entire time of operation of the Compton Gamma-Ray Observatory (1991–2000). Two of these 11 gamma-ray bursts have light curves with three components. The possibility of gravitational mesolensing of these gamma-ray bursts on the King's type bodies is investigated.  相似文献   

20.
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