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221.
本文叙述曲面和任意取向表面表面摩阻测量方法的进一步的发展。介绍用漫射照明获取薄油膜等厚度干涉条纹谱的理论根据和实验结果。讨论了通过油流显示图像的分析,自动探测表面流线方位的可能性。所得结论表明油膜法也能应用于复杂的三维流动。  相似文献   
222.
本文描述的是研究爆炸成型发射弹(EFP)模型的流场及超高速空气动力特性所用的弹道试验设备;简要报导了记录全尺寸干涉图形的技术;对径向密度分布再现的方法进行了讨论;在零攻角实验时不同模型的空气动力阻力是采用简化方法来计算的;对各种不同EFP型式的气动稳定性提出了定性估计的方法;并阐述了用于组合体超高速飞行特性研究的数值计算技术的基本原理  相似文献   
223.
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。  相似文献   
224.
The orbiting solar telescope on Salyut-4 (F = 2,5 m, d = 250 mm) produces images of the Sun on the entrance slit of a stigmatic two-grating spectrograph (R1 = 1 m, N1 = 1200 lines/mm; R2 = 0.5 m, N2 = 2400 lines/mm, dispersion 16 Å/mm, spectral resolution 0,3 Å). The automatic system keeps the observed solar features on the slit of the spectrograph with an accuracy of 3–4 arc sec. The far UV-spectra (970–1400 Å) of solar flares, brightenings, flocculi and prominences were photographed and fresh coatings of mirrors were made during the flight.  相似文献   
225.
Magnetic data from a newly commissioned Indian Antarctic station Bharati (corrected geomagnetic (CGM) coordinates 74.7°S, 97.2°E) and closely-spaced IMAGE chain observatories (∼100° magnetic meridian in Northern hemisphere) has been analyzed to study the climatology of substorms which were localized poleward of the standard auroral oval. We considered four austral summers (year 2007–2010) when data from Bharati was available. Several very high latitude substorms were observed in this duration when the solar activity remained unexpectedly low for a long time. Various features of very high latitude substorms, e.g., local time dependence, interplanetary state, hemispherical asymmetry and their nightside low latitude signatures are examined. Events studied here, suggested the following properties of substorms occurring at very high latitudes: (1) maximum occurrence was observed near magnetic midnight (21:00–02:00 MLT). (2) In contradiction to earlier reports, many substorms were observed even during negative IMF Bz condition. In addition, majority of substorms occurred during low or moderate solar wind streams. (3) Magnetic signatures were often pronounced in the winter hemisphere. (4) Even if widely used standard AE indices fail to monitor very high latitude substorms, their low latitude signatures are often evident.  相似文献   
226.
227.
Surface chemistry of airless bodies in the solar system can be derived from remote X-ray spectral measurements from an orbiting spacecraft. X-rays from planetary surfaces are excited primarily by solar X-rays. Several experiments in the past have used this technique of X-ray fluorescence for deriving abundances of the major rock forming elements. The Chandrayaan-2 orbiter carries an X-ray fluorescence experiment named CLASS that is designed based on results from its predecessor C1XS flown on Chandrayaan-1. We discuss the new aspects of lunar science that can be potentially achieved with CLASS.  相似文献   
228.
气象因子对夏季电力负荷影响的分析   总被引:7,自引:0,他引:7  
本文应用2002、2003两年的夏季资料,通过对日最高气温、最低气温、平均气温、风速、相对湿度和气压等气象要素与南昌用电量的对比分析,建立了用电负荷预测模型,应用于2004年南昌夏季高温用电负荷预测,并在此基础上与江西省电力公司联合在江西省卫视一套18:53分的气象预报节目中发布《电力需求气象预警信息》,获得了很好的社会经济效益。  相似文献   
229.
The main purposes of experiment “Obstanovka” (“Environment” in Russian) consisting of several instruments are to measure a set of electromagnetic and plasma phenomena characterizing the space weather conditions, and to evaluate how such a big and highly energy consuming body as the International Space Station disturbs the surrounding plasma, and how the station itself is charged due to the operation of so many instruments, solar batteries, life supporting devices, etc. Two identical Langmuir electrostatic probes are included in the experiment “Obstanovka”. In this paper the Langmuir probes for “Obstanovka” experiment are described, including the choice of geometry (spherical or cylindrical), a more reliable method for the sweep voltage generation, an adaptive algorithm for the probe’s operation. Special attention is paid to the possibility for remote upgrading of the instrument from the ground using the standard communication channels.  相似文献   
230.
We present the observations of He-like Ar triplet lines obtained by RESIK spectrometer aboard CORONAS-F. Interpretation of intensity ratios between triplet lines of lower Z elements is known to provide useful diagnostics of plasma conditions within the emitting source. Here, we investigate whether triplet line ratios are useful for interpretation of higher Z element spectra. A high sensitivity, low background and precise absolute calibration of RESIK allow to consider in addition also the continuum contribution. This provides a way to determine the Ar absolute abundance from the observed triplet component ratios. The method is presented and the results are shown for two selected flares. Derived values of Ar absolute abundance for these flares are found to be similar: 2.6 × 10−6 and 2.9 × 10−6. They fall in the range between presently accepted Ar photospheric and coronal abundances.  相似文献   
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